Coronaviruses are widespread in nature and can infect mammals and poultry,making them a public health concern.Globally,prevention and control of emerging and re-emerging animal coronaviruses is a great challenge.The m...Coronaviruses are widespread in nature and can infect mammals and poultry,making them a public health concern.Globally,prevention and control of emerging and re-emerging animal coronaviruses is a great challenge.The mecha-nisms of virus-mediated immune responses have important implications for research on virus prevention and control.The antigenic epitope is a chemical group capable of stimulating the production of antibodies or sensitized lympho-cytes,playing an important role in antiviral immune responses.Thus,it can shed light on the development of diagnos-tic methods and novel vaccines.Here,we have reviewed advances in animal coronavirus antigenic epitope research,aiming to provide a reference for the prevention and control of animal and human coronaviruses.展开更多
Mango(Mangifera indica L.)is a tropical fruit that is widely consumed as both fresh fruits and processed products around the world.The high incidence of mango allergy,on the other hand,has sparked widespread concern.T...Mango(Mangifera indica L.)is a tropical fruit that is widely consumed as both fresh fruits and processed products around the world.The high incidence of mango allergy,on the other hand,has sparked widespread concern.Therefore,a summary and analysis of the current status and issues in mango allergen research can guide in-depth study on the mechanism of mango allergy and reveal effective desensitization methods.We described the incidence of fruit allergy,as well as the mechanism and clinical symptoms of mango allergy,in this review.We also looked into the structural properties of mango allergens,the effect of processing methods on mango allergens,prediction methods for mango allergen epitopes,and the current state of research on mango cross-reactive allergens and preventive measures.Finally,the research directions and ideas for the future are proposed and discussed.展开更多
Quail egg ovomucoid can inhibit activation of basophils and eosinophils,while hen egg ovomucoid has been shown to be a major allergen,named Gal d 1.At present,the differences in structure and function between two ovom...Quail egg ovomucoid can inhibit activation of basophils and eosinophils,while hen egg ovomucoid has been shown to be a major allergen,named Gal d 1.At present,the differences in structure and function between two ovomucoid are unclear.We found the homology of ovomucoid in quail eggs and hen eggs reached77%.Compared with hen egg ovomucoid,the distribution of secondary structure was different in AA52-53,AA57-58,AA66-68,AA71-72,AA131-133,AA139-140,AA157-159 and AA184-185.Among 9 epitopes of egg ovomucoid,there were different amino acids from quail egg ovomucoid in 8 epitopes.Recombination quail egg ovomucoid had trypsin inhibition activity and quail egg ovomucoid didn't specifically bind to serum of eggs allergic patients.Quail egg ovomucoid can significantly inhibit RBL-2 H3 cells degranulation and protect cells morphology to a certain extent,indicating quail egg ovomucoid can inhibit cells activation and have potential anti-allergic effects,which is related to trypsin inhibitory activity.The difference in sensitization compare to hen egg ovomucoid may be due to amino acids differences affecting protein structure by changing antigenic epitopes.展开更多
[Objective] The B cell epitopes for VP73 protein of African swine fever virus was predicted. [ Method] Based on the analysis of the amino acid sequence and the flexible regions of VP73 protein, the B cell epitopes for...[Objective] The B cell epitopes for VP73 protein of African swine fever virus was predicted. [ Method] Based on the analysis of the amino acid sequence and the flexible regions of VP73 protein, the B cell epitopes for VP73 protein of African swine fever virus were predicted by method of Kyte-Doolittie, Emini and Jameson-Wolf. [Result] The B cell epitopes were located at or adjacent to the N-terminal No. 11 - 18,26 -48,73 -82,136 - 150,159 - 174,181 - 189,191 - 210,247 - 276,279 - 295,313 - 323 and 382 - 392. [Conclusion] The multi-parameters analytic method was adopted to predict the B cell epitopes for VP73 protein of African swine fever virus, which laid solid foundation for further characterizing the protein of VP73 and researching epitope vaccine.展开更多
[Objective] To predict the secondary structure and B cell epitopes of the rice major allergen RAG1. [Method] The amino acid sequence of rice allergen RAG1 was acquired from Expasy protein database. The secondary struc...[Objective] To predict the secondary structure and B cell epitopes of the rice major allergen RAG1. [Method] The amino acid sequence of rice allergen RAG1 was acquired from Expasy protein database. The secondary structure of RAG1 was predicted by DNAStar Protean software with Gamier-Robson program, Chou-Fasman program and Karplus-Schulz program; the B cell epitopes of RAG1 was predicted with the Kyte Doolittle hydrophilic program, Emini surface accessibility program and Jameson-Wolf antigenic index program. [Result] The predictions on secondary structure and B cell epitopes showed that the regions of 33-44, 119-129, 155-163 were the dominant B cell epitopes. [Conclusion] This study predicted the potential dominant B cell epitopes in rice allergen RAG1 by comprehensive use of multi-methods and multi-parameters, and provided a theoretical basis for further researches on identification, antigen modification and epitope vaccine design of RAG1 B cell epitopes.展开更多
AIM: To identify hepatitis C virus(HCV) core protein epitopes recognized by HLA-A2 restricted cytotoxic T lymphocyte (CTL). METHODS: Utilizing the method of computer prediction followed by a 4h(51)Cr release assay con...AIM: To identify hepatitis C virus(HCV) core protein epitopes recognized by HLA-A2 restricted cytotoxic T lymphocyte (CTL). METHODS: Utilizing the method of computer prediction followed by a 4h(51)Cr release assay confirmation. RESULTS: The results showed that peripheral blood mononuclear cells (PBMC) obtained from two HLA-A2 positive donors who were infected with HCV could lyse autologous target cells labeled with peptide "ALAHGVRAL (core 150-158)". The rates of specific lysis of the cells from the two donors were 37.5% and 15.8%, respectively. Blocking of the CTL response with anti-CD4 mAb caused no significant decrease of the specific lysis. But blocking of CTL response with anti-CD8 mAb could abolish the lysis. CONCLUSION: The peptide (core 150-158) is the candidate epitope recognized by HLAA2 restricted CTL.展开更多
Objective:To analyze the structure of aquaporins-3(AQP-3) from Schistosoma japonicum(SJAQP-3) using bioinformalical methods,and to provid of references for vaccine targets research.Methods:Protparam,BepiPred,TMHMM Ser...Objective:To analyze the structure of aquaporins-3(AQP-3) from Schistosoma japonicum(SJAQP-3) using bioinformalical methods,and to provid of references for vaccine targets research.Methods:Protparam,BepiPred,TMHMM Server,MLRC,Geno3d,DNA star software packages were used to predict the physical and chemical properties,hydrophilicity plot, flexibility regions,antigenic index,surface probability plot,secondary structure,and tertiary structure of amino acid sequence of SJAQP-3.Results:SJAQP-3 had six transmembrane regions and two half-spanning helices that form a central channel.The half-spanning helices fold into the centre of the channel.Either of the half-spanning helix had a conserved motif of NPA common to all aquaporins.Predicted linear B-Cell epitopes were most likely at the N-terminal amino acid residues of Saa-7aa,59aa- 62aa,225aa-230aa,282aa -288aa,294aa -29Saa and 305aa -307aa area.59aa- 62aa,22Saa-230aa located outside the membrane,the others located inside the cell.Conclusions:SJAQP-3 is a integral membrane protein in Schistosoma japonicum tegument.There are six potential epitopes in SJ AQP-3.It might be a potential molecular target for the development of vaccines.展开更多
AIM:To search for further immunodominant peptides of the pyruvate dehydrogenase complex E2-component (PDC-E2) recognized by antimitochondrial antibodies (AMA) in primary biliary cirrhosis (PBC). METHODS:Sera from 95 p...AIM:To search for further immunodominant peptides of the pyruvate dehydrogenase complex E2-component (PDC-E2) recognized by antimitochondrial antibodies (AMA) in primary biliary cirrhosis (PBC). METHODS:Sera from 95 patients with PBC were tested by enzyme-linked immunosorbent assay against 33 synthetic overlapping peptides (25 amino acids; aa) covering the entire length of the E2-subunit of PDC-E2. Furthermore,the inner lipoyl peptide 167-184 was used in an unlip oylated and a lipoylated form as well as coupled to ovalbumin. Sera from 11 AMA negative/ANA posit ive PBC patients,63 patients with other liver disorders and 22 healthy blood donors served as controls.RESULTS:Of the 95 PBC-sera,74% reacted with the peptide 475-499 and 58% with the pept ide 407-431 located within the catalytic domain of PDC-E2. Patients with other disorders or healthy controls were positive in only up to 18%. Antibodies to the unlipoylatedand lip oylated pept ide 167-184 within the inner lipoyl domain were found in only 5% and 11% of the PBC sera,respectively; using ovalbumin-coupled peptides,the incidence increased up to 57% (unlipoylated form). CONCLUSION:Peptides within the catalytic site of PDC-E2 rather than the previously reported lipoyl binding peptide 167-184 may represent major immunodomin ant epitopes recognized by AMA in PBC.展开更多
In recent years,the in silico epitopes prediction tools have facilitated the progress of vaccines development significantly and many have been applied to predict epitopes in viruses successfully. Herein,a general over...In recent years,the in silico epitopes prediction tools have facilitated the progress of vaccines development significantly and many have been applied to predict epitopes in viruses successfully. Herein,a general overview of different tools currently available,including T cell and B cell epitopes prediction tools,is presented. And the principles of different prediction algorithms are reviewed briefly. Finally,several examples are present to illustrate the application of the prediction tools.展开更多
To compare the effects of polysaccharide nucleic acid fraction of bacillus calmette guerin (BCG PSN) and thymopeptides on T lymphocytes of normal and immunosuppressed mice, CD4 + and CD8 + T lymphocyte subsets of...To compare the effects of polysaccharide nucleic acid fraction of bacillus calmette guerin (BCG PSN) and thymopeptides on T lymphocytes of normal and immunosuppressed mice, CD4 + and CD8 + T lymphocyte subsets of single nucleic cell in thymus, spleen and peripheral blood were detected successively by flow cytometry after application of BCG PSN and thymopeptides. Meanwhile, CD4 +/CD8 + ratio was also calculated. The results showed that both BCG PSN and thymopeptides could decrease the proportion of CD4 + CD8 + T lymphocyte subsets in the thymus, at the same time increase CD4 + T lymphocyte, CD8 +T lymphocyte proportion in the three tissues. The fluctuation in amplitude was greater in thymopeptides group than that in BCG PSN group. It is concluded that acting location of thymopeptides is in thymus, its stimulating action is stronger than that of BCG PSN, while BCG PSN not only accelerates the differentiation in thymus, but also has some direct stimulation to peripheral CD4 +T lymphocytes, and can maintain CD4 +/CD8 + ratio within normal range. So, BCG PSN is safer.展开更多
Objective:To predict B cell and T cell epitopes of 22-kDa,47-kDa,56-kDa and 58-kDa proteins.Methods:The sequences of 22-kDa,47-kDa,56-kDa and 58-kDa proteins which were derived from Orientia tsutsugamushi were analyze...Objective:To predict B cell and T cell epitopes of 22-kDa,47-kDa,56-kDa and 58-kDa proteins.Methods:The sequences of 22-kDa,47-kDa,56-kDa and 58-kDa proteins which were derived from Orientia tsutsugamushi were analyzed by SOPMA,DNAstar,Bcepred,ABCpred,NetMHC,NetMHCⅡand IEDB.The 58-kDa tertiary structure model was built by MODELLER9.17.Results:The 22-kDa B-cell epitopes were located at positions 194-200,20-26 and 143-154,whereas the T-cell epitopes were located at positions 154-174,95-107,17-25 and 57-65.The 47-kD a protein B-cell epitopes were at positions 413-434,150-161 and 283-322,whereas the T-cell epitopes were located at positions 129-147,259-267,412-420 and 80-88.The 56-kDa protein B-cell epitopes were at positions 167-173,410-419 and 101-108,whereas the T-cell epitopes were located at positions 88-104,429-439,232-240 and 194-202.The 58-kDa protein B-cell epitopes were at positions 312-317,540-548 and 35-55,whereas the T-cell epitopes were located at positions 415-434,66-84 and 214-230.Conclusions:We identified candidate epitopes of 22-kDa,47-kDa,56-kDa and 58-kDa proteins from Orientia tsutsugamushi.In the case of 58-kDa,the dominant antigen is displayed on tertiary structure by homology modeling.Our findings will help target additional recombinant antigens with strong specificity,high sensitivity,and stable expression and will aid in their isolation and purification.展开更多
BACKGROUND: The patient with malignant tumor always show immunologic function drawback and ingravescent with tumor development, especially in the aspect of cell-mediated immunity. This study was undertaken to define t...BACKGROUND: The patient with malignant tumor always show immunologic function drawback and ingravescent with tumor development, especially in the aspect of cell-mediated immunity. This study was undertaken to define the relationship between the immune function of local cells and cancer development by investigating the distribution of natural killer (NK) cells and T-lymphocyte subsets in peripheral blood, the cancer tissue and the tissue surrounding gallbladder carcinoma. METHODS: The numbers of CD4(+) and CD8(+) T-lymphocytes and NK cells were measured by flow cytometry in samples taken from gallbladder cancer tissue, the surrounding tissues and peripheral blood of 38 patients, and compared with the numbers in the peripheral blood and gallbladder tissue of 30 patients with cholecystitis as controls. RESULTS: The numbers of CD4(+) and CD8(+) T-cells and NK cells in gallbladder cancer tissues were significantly higher than those in the surrounding tissue and gallbladder with gallstone. However, the ratio of CD4(+)/CD8(+) was lower in the cancer tissue than that in the surrounding tissue and tissue from gallbladders with gallstones. The distribution of CD4(+) and CD8(+) T-cells and NK cells in mucous membrane of cholecystitis gallbladder and that in the tissue surrounding gallbladder cancer were significantly different. CONCLUSIONS: Disproportionate and imbalanced distribution of NK cells and subsets of T-lymphocytes occurs in the mucous membrane proper of gallbladder cancer and surrounding tissue. Although gallbladder cancer tissue has higher expressions of CD4(+), CD8(+) and NK cells, the immune function is low or in an inhibited state. In gallbladder cancer immunization therapy, local cellular immunological function should be enhanced and the protective barrier improved.展开更多
AIM:To investigate the variability of the main immunodominant motifs of hepatitis B virus(HBV) core gene by ultra-deep-pyrosequencing(UDPS).METHODS:Four samples(2 genotype A and 2 genotype D) from 4 treatment-na ve pa...AIM:To investigate the variability of the main immunodominant motifs of hepatitis B virus(HBV) core gene by ultra-deep-pyrosequencing(UDPS).METHODS:Four samples(2 genotype A and 2 genotype D) from 4 treatment-na ve patients were assessed for baseline variability.Two additional samples from one patient(patient 4,genotype D) were selected for analysis:one sample corresponded to a 36-mo treatment-free period from baseline and the other to the time of viral breakthrough after 18 mo of lamivudine treatment.The HBV region analyzed covered amino acids 40 to 95 of the core gene,and included the two main epitopic regions,Th50-69 and B74-84.UDPS was carried out in the Genome Sequencer FLX system(454 Life Sciences,Roche).After computer filtering of UDPS data based on a Poisson statistical model,122 813 sequences were analyzed.The most conserved position detected by UDPS was analyzed by site-directed mutagenesis and evaluated in cell culture.RESULTS:Positions with highest variability rates were mainly located in the main core epitopes,confirming their role as immune-stimulating regions.In addition,the distribution of variability showed a relationship with HBV genotype.Patient 1(genotype A) presented the lowest variability rates and patient 2(genotype A) had 3 codons with variability higher than 1%.Patient 3 and 4(both genotype D) presented 5 and 8 codons with variability higher than 1%,respectively.The median baseline frequencies showed that genotype A samples had higher variability in epitopic positions than in the other positions analyzed,approaching significance(P = 0.07,sample 1 and P = 0.05,sample 2).In contrast,there were no significant differences in variability between the epitopic and other positions in genotype D cases.Interestingly,patient 1 presented a completely mutated motif from amino acid 64 to 67(E 64 LMT 67),which is commonly recognized by T helper cells.Additionally,the variability observed in all 4 patients was particularly associated with the E 64 LMT 67 motif.Codons 78 and 79 were highly conserved in all samples,in keeping with their involvement in the interaction between the HBV virion capsid and the surface antigens(HBsAg).Of note,codon 76 was even more conserved than codons 78 and 79,suggesting a possible role in HBsAg interactions or even in hepatitis B e antigen conformation.Sequential analysis of samples from patient 4(genotype D) illustrated the dynamism of the HBV quasispecies,with strong selection of one minor baseline variant coinciding with a decrease in core variability during the treatment-free and lamivudinetreated period.The drop in variability seemed to result from a "steady state" situation of the HBV quasispecies after selection of the variant with greatest fitness.CONCLUSION:Host immune pressure seems to be the main cause of HBV core evolution.UDPS analysis is a useful technique for studying viral quasispecies.展开更多
Objective: To investigate the potential and early effect of hypertonic saline resuscitation on T-lymphocyte sub- populations in rats with hemorrhagic shock. Methods: A model of rat with severe hemorrhagic shock was es...Objective: To investigate the potential and early effect of hypertonic saline resuscitation on T-lymphocyte sub- populations in rats with hemorrhagic shock. Methods: A model of rat with severe hemorrhagic shock was established in 18 Sprague-Dawley (SD) rats. The rats were randomly divided into Sham group, HTS group (hypertonic saline resuscitation group) and NS group (normal saline resuscitation group). Each group contained 6 rats. The CD4+ and CD8+ subpopulations of T-lymphocytes in peripheral blood were detected respectively before shock and after resuscitation by double antibody labelling and flow cytometry. Results: In the early stage after hemorrhagic shock, fluid resuscitation and emergency treatment, the CD4+ lymphocytes of peripheral blood in HTS and NS groups markedly increased. Small volume resuscitation with HTS also induced peripheral CD8+ lymphocytes to a certain extent, whereas NS resuscitation showed no effect in this respect. Consequently, compared with Sham and HTS groups, CD4+/CD8+ ratio of peripheral blood in NS group was obviously increased, and showed statistically differences. Conclusion: In this model of rat with severe hemorrhagic shock, small volume resuscitation with HTS is more effective than NS in reducing immunologic disorders and promoting a more balanced profile of T-lymphocyte subpopula- tions regulating network.展开更多
AIM: To investigate peripheral T-lymphocyte sub-population profile and its correlation with hepatitis B virus (HBV) replication in patients with chronic hepatitis B (CHB).METHODS: Distribution of T-lymphocyte subpopul...AIM: To investigate peripheral T-lymphocyte sub-population profile and its correlation with hepatitis B virus (HBV) replication in patients with chronic hepatitis B (CHB).METHODS: Distribution of T-lymphocyte subpopulations in peripheral blood was measured by flow cytometry in 206 CHB patients. HBV markers were detected with ELISA. Serum HBV DNA load was assessed with quantitative real-time polymerase chain reaction (PCR). The relationship between HBV replication and variation in peripheral T-cell subsets was analyzed.RESULTS: CHB patients had significantly decreased CD3+ and CD4+ cells and CD4+/CD8+ ratio, and increased CD8+ cells compared with uninfected controls (55.44 ± 12.39 vs 71.07 ± 4.76, 30.92 ± 7.48 vs 38.94 ± 3.39, 1.01 ± 0.49 vs 1.67 ± 0.33, and 34.39 ± 9.22 vs 24.02 ± 4.35; P < 0.001, respectively). Univariate analysis showed a similar pattern of these parameters was significantly associated with high viral load, presence of serum hepatitis B e antigen (HBeAg) expression, liver disease severity, history of maternal HBV infection, and young age at HBV infection, all with P < 0.01. There was a significant linear relationship between viral load and these parameters of T-lymphocyte subpopulations (linear trend test P < 0.001). There was a negative correlation between the levels of CD3+ and CD4+ cells and CD4+/CD8+ ratio and serum level of viral load in CHB patients (r = -0.68, -0.65 and -0.75, all P < 0.0001), and a positive correlation between CD8+ cells and viral load (r = 0.70, P < 0.0001). There was a significant decreasing trend in CD3+ and CD4+ cells and CD4+/CD8+ ratio with increasing severity of hepatocyte damage and decreasing age at HBV infection (linear trend test P < 0.01). In multiple regression (after adjustment for age at HBV infection, maternal HBV infection status and hepatocyte damage severity) log copies of HBV DNA maintained a highly significant predictive coefficient on T-lymphocyte subpopulations, and was the strongest predictor of variation in CD3+, CD4+, CD8+ cells and CD4+/CD8+ ratio. However, the effect of HBeAg was not significant.CONCLUSION: T-lymphocyte failure was signifi-cantly associated with viral replication level. The substantial linear dose-response relationship and strong independent predictive effect of viral load on T-lymphocyte subpopulations suggests the possibility of a causal relationship between them, and indicates the importance of viral load in the pathogenesis of T cell hyporesponsiveness in these patients.展开更多
AIM: To assess the three polymorphJsm regions within cytotoxic T-lymphocyte antigen 4 (CTLA-4) gene, a C/T base exchange in the promoter region-318 (CTLA-4 -318C/T), an A/G substitution in the exon 1 position 49 ...AIM: To assess the three polymorphJsm regions within cytotoxic T-lymphocyte antigen 4 (CTLA-4) gene, a C/T base exchange in the promoter region-318 (CTLA-4 -318C/T), an A/G substitution in the exon 1 position 49 (CTLA-4 49A/G), a T/C substitution in 1172 (CTLA-4 -1172T/C) in patients with chronic hepatitis B. METHODS: Fifty-one patients with chronic hepatitis B virus infection and 150 healthy subjects were recruited sequentially as they presented to the hepatic clinic. Classification of chronic hepatitis B virus (HBV)-infected patients was as asymptomatic carrier state (26 patients) and chronic hepatitis B (25 patients). Genomic DNA was isolated from anti-coagulated peripheral blood Bully coat using Miller's salting-out method. The presence of the CTLA-4 gene polymorphisms was determined using polymerase chain reaction amplification refractory mutation system (ARMS). RESULTS: We observed a significant association between -318 genotypes frequency (T+C-, T+C+, T-C+) and susceptibility to chronic hepatitis B (P=0.012, OR=0.49, 95%CI: 0.206-1.162). However, we did not observe a significant association for +49 genotype frequency (T+C+, T+C- T-C+) and -1172 genotype frequency (C+T+, T+C- C+T-) and state of disease. CONCLUSION: Our results suggest that CTLA-4 gene polymorphisms may partially be involved in the susceptibility to chronic hepatitis B.展开更多
AIM:To investigate the peripheral T-lymphocyte subpopulation profile,and its correlations with hepatitis B virus(HBV) replication level in chronic HBV-infected(CHI) individuals with normal liver function tests(LFTs) ....AIM:To investigate the peripheral T-lymphocyte subpopulation profile,and its correlations with hepatitis B virus(HBV) replication level in chronic HBV-infected(CHI) individuals with normal liver function tests(LFTs) . METHODS:Frequencies of T-lymphocyte subpopu-lations in peripheral blood were measured by flow cytometry in 216 CHI individuals. HBV markers were detected with ELISA. Serum HBV DNA load was assessed with quantitative real-time PCR. Information of age at HBV infection,and maternal HBV infection status was collected. ANOVA linear trend test and linear regression were used in statistical analysis. RESULTS:CHI individuals had significantly decreased relative frequencies of CD3+,CD4+ subpopulationsand CD4+/CD8+ ratio,and increased CD8+ subset percentage compared with uninfected individuals(all P < 0.001) . There was a significant linear relationship between the load of HBV DNA and the parameters of T-lymphocyte subpopulations(ANOVA linear trend test P < 0.01) . The parameters were also significantly worse among individuals whose mothers were known to be HBV carriers,and those having gained infection before the age of 8 years. In multiple regressions,after adjustment for age at HBV infection and status of maternal HBV infection,log copies of HBV DNA maintained its highly significant predictive coefficient on T-lymphocyte subpopulations,whereas the effect of HBeAg was not significant. CONCLUSION:HBV DNA correlates with modification in the relative T-lymphocyte subpopulation frequencies. High viral load is more powerful than HBeAg in predicting the impaired balance of T-cell subsets.展开更多
In this study, the coding region of type O FMDV capsid protein VP1 and a series of codon optimized DNA sequences coding for VP1 amino acid residues 141-160 (epitopel), tandem repeat 200-213 (epitope2 (+2)) and ...In this study, the coding region of type O FMDV capsid protein VP1 and a series of codon optimized DNA sequences coding for VP1 amino acid residues 141-160 (epitopel), tandem repeat 200-213 (epitope2 (+2)) and the combination of two epitopes (epitopel-2) was genetically cloned into the prokaryotic expression vector PPRoExHTb and pGEX4T-1, respectively. VP1 and the fused epitopes GST-E1, GST-E2 (+2) and GST-E1-2 were successfully solubly expressed in the cytoplasm of Escherichia coli and Western blot analysis demonstrated they retained antigenicity. Indirect VP1-ELISA and epitope ELISAs were subsequently developed to screen a panel of 80 field pig sera using LPB-ELISA as a standard test. For VP1-ELISA and all the epitope ELISAs, there were clear distinctions between the FMDV-positive and the FMDV-negative samples. Cross-reactions with pig sera positive to the viruses of swine vesicular disease virus that produce clinically indistinguishable syndromes in pigs or guinea pig antisera to FMDV strains of type A, C and Asia1 did not occur. The relative sensitivity and specificity for the GST-E1 ELISA, GST-E2 (+2), GST-E1-2 ELISA and VP1-ELISA in comparison with LPB-ELISA were 93.3% and 85.0%, 95.0% and 90%, 100% and 81.8%, 96.6% and 80.9% respectively. This study shows the potential use of the aforementioned epitopes as alternatives to the complex antigens used in current detection for antibody to FMDV structural proteins.展开更多
Study Objective: To observe the effect of dexmedetomidine (DEX) on T-lymphocyte subsets and natural killer (NK) cells in the peripheral blood of perioperative patients with colorectal cancer. Design: A random double-b...Study Objective: To observe the effect of dexmedetomidine (DEX) on T-lymphocyte subsets and natural killer (NK) cells in the peripheral blood of perioperative patients with colorectal cancer. Design: A random double-blind control clinical study. Setting: A university hospital. Patients: Forty patients with colorectal cancer, ASA I-П. Interventions: All patients were randomly divided into a DEX group (n = 20) and a control group (n = 20). Before induction of anesthesia, epidural catheters were placed in the L1-L2 or T12-L1 intervertebral spaces. The DEX group received 1 μg/kg of DEX (200 μg/50 ml) intravenously for 15 min prior to the surgery, which was then infused at a rate of 0.5 μg/kg/h until 30 min before the end of the surgery. The control group received an intravenous infusion of saline (50 ml) instead of DEX during the same periods as the DEX group. All patients received routine anesthesia and postoperative analgesia. Measurements: Blood samples from all patients were collected at the following time points: before anesthesia (T0), 24 h after surgery (T1), 48 h after surgery (T2) and 72 h after surgery (T3). Changes in T-lymphocyte subsets (CD3+, CD4+, CD8+, CD4+/CD8+) and NK cells were determined by flow cytometry. Main Results: Compared with the control group, the percentages of CD3+ and CD4+ cells and the CD4+/CD8+ ratio in the DEX group increased significantly from T1 to T3展开更多
The major envelope glycoprotein E of dengue (DEN) virus plays a central role in the biology of flaviviruses. It is capable of inducing a protective immune response in vivo and responsible for the viral binding to the ...The major envelope glycoprotein E of dengue (DEN) virus plays a central role in the biology of flaviviruses. It is capable of inducing a protective immune response in vivo and responsible for the viral binding to the cellular receptor. The crystal structures of glycoprotein E ectodomains have already been determined. However, it is still un-clear where the well-defined B-cell epitopes for glycoprotein E which induce the neutralizing an-tibodies locates. Thus, in order to characterize the role of glycoprotein E in the pathogenesis of dengue virus infection, we first used network servers (http://bio.dfci. harvard.edu/Tools/ &amp;http://www. imtech. res. in) to predict and analyze the well defined B-cell and T-cell epitopes of the glycoprotein of the DEN-1 HAWAII strain. Then based on the highly conserved envelop glyco-protein amino acids, the hydrophilicity, antigenic-ity, accessibility and flexibility of envelop glyco-protein E were further predicted by using Biotic softwares (DNASTAR) and network servers (http://bio. dfci.harvard.edu/Tools/), the secondary structure was putatively obtained. In our study, the sequence at 281-295 amino acid (aa) for den-gue virus type 1 HAWAII strain and the sequence at 345-359, 383-397 for dengue virus type 2 NGC strain were predicted as the more prevalent epi-topes by using multiple parameters and different analysis softwares, respectively. Two epitopes of DEN-2 and one of DEN-1 locate on the domain Ш and domainⅡ of the protein E, respectively. Sub-sequently, further studies will be carried out to examine the antigenicity and protection of the synthetic peptides with higher scores in the av-erage antigen index (AI) and better hydrophilic properties determined by our data.展开更多
基金supported by the Natural Science Foundation of Zhejiang Province(Q23C180006)the Zhejiang A&F University Talent Initiative Project(118-203402005901).
文摘Coronaviruses are widespread in nature and can infect mammals and poultry,making them a public health concern.Globally,prevention and control of emerging and re-emerging animal coronaviruses is a great challenge.The mecha-nisms of virus-mediated immune responses have important implications for research on virus prevention and control.The antigenic epitope is a chemical group capable of stimulating the production of antibodies or sensitized lympho-cytes,playing an important role in antiviral immune responses.Thus,it can shed light on the development of diagnos-tic methods and novel vaccines.Here,we have reviewed advances in animal coronavirus antigenic epitope research,aiming to provide a reference for the prevention and control of animal and human coronaviruses.
基金supported by National Science and Technology Major Project of China (2019YFC1605002)National Natural Science Foundation of China (31872886)。
文摘Mango(Mangifera indica L.)is a tropical fruit that is widely consumed as both fresh fruits and processed products around the world.The high incidence of mango allergy,on the other hand,has sparked widespread concern.Therefore,a summary and analysis of the current status and issues in mango allergen research can guide in-depth study on the mechanism of mango allergy and reveal effective desensitization methods.We described the incidence of fruit allergy,as well as the mechanism and clinical symptoms of mango allergy,in this review.We also looked into the structural properties of mango allergens,the effect of processing methods on mango allergens,prediction methods for mango allergen epitopes,and the current state of research on mango cross-reactive allergens and preventive measures.Finally,the research directions and ideas for the future are proposed and discussed.
基金supported by the Beijing Municipal Natural Science Foundation of China(7202100)。
文摘Quail egg ovomucoid can inhibit activation of basophils and eosinophils,while hen egg ovomucoid has been shown to be a major allergen,named Gal d 1.At present,the differences in structure and function between two ovomucoid are unclear.We found the homology of ovomucoid in quail eggs and hen eggs reached77%.Compared with hen egg ovomucoid,the distribution of secondary structure was different in AA52-53,AA57-58,AA66-68,AA71-72,AA131-133,AA139-140,AA157-159 and AA184-185.Among 9 epitopes of egg ovomucoid,there were different amino acids from quail egg ovomucoid in 8 epitopes.Recombination quail egg ovomucoid had trypsin inhibition activity and quail egg ovomucoid didn't specifically bind to serum of eggs allergic patients.Quail egg ovomucoid can significantly inhibit RBL-2 H3 cells degranulation and protect cells morphology to a certain extent,indicating quail egg ovomucoid can inhibit cells activation and have potential anti-allergic effects,which is related to trypsin inhibitory activity.The difference in sensitization compare to hen egg ovomucoid may be due to amino acids differences affecting protein structure by changing antigenic epitopes.
文摘[Objective] The B cell epitopes for VP73 protein of African swine fever virus was predicted. [ Method] Based on the analysis of the amino acid sequence and the flexible regions of VP73 protein, the B cell epitopes for VP73 protein of African swine fever virus were predicted by method of Kyte-Doolittie, Emini and Jameson-Wolf. [Result] The B cell epitopes were located at or adjacent to the N-terminal No. 11 - 18,26 -48,73 -82,136 - 150,159 - 174,181 - 189,191 - 210,247 - 276,279 - 295,313 - 323 and 382 - 392. [Conclusion] The multi-parameters analytic method was adopted to predict the B cell epitopes for VP73 protein of African swine fever virus, which laid solid foundation for further characterizing the protein of VP73 and researching epitope vaccine.
基金Supported by the National Natural Science Foundation of China(30771240)the Academic Team for Scientific Research Innovation of Guangzhou Education System(B94118)~~
文摘[Objective] To predict the secondary structure and B cell epitopes of the rice major allergen RAG1. [Method] The amino acid sequence of rice allergen RAG1 was acquired from Expasy protein database. The secondary structure of RAG1 was predicted by DNAStar Protean software with Gamier-Robson program, Chou-Fasman program and Karplus-Schulz program; the B cell epitopes of RAG1 was predicted with the Kyte Doolittle hydrophilic program, Emini surface accessibility program and Jameson-Wolf antigenic index program. [Result] The predictions on secondary structure and B cell epitopes showed that the regions of 33-44, 119-129, 155-163 were the dominant B cell epitopes. [Conclusion] This study predicted the potential dominant B cell epitopes in rice allergen RAG1 by comprehensive use of multi-methods and multi-parameters, and provided a theoretical basis for further researches on identification, antigen modification and epitope vaccine design of RAG1 B cell epitopes.
基金the National Nature Science Foundation of China,No.39800121
文摘AIM: To identify hepatitis C virus(HCV) core protein epitopes recognized by HLA-A2 restricted cytotoxic T lymphocyte (CTL). METHODS: Utilizing the method of computer prediction followed by a 4h(51)Cr release assay confirmation. RESULTS: The results showed that peripheral blood mononuclear cells (PBMC) obtained from two HLA-A2 positive donors who were infected with HCV could lyse autologous target cells labeled with peptide "ALAHGVRAL (core 150-158)". The rates of specific lysis of the cells from the two donors were 37.5% and 15.8%, respectively. Blocking of the CTL response with anti-CD4 mAb caused no significant decrease of the specific lysis. But blocking of CTL response with anti-CD8 mAb could abolish the lysis. CONCLUSION: The peptide (core 150-158) is the candidate epitope recognized by HLAA2 restricted CTL.
文摘Objective:To analyze the structure of aquaporins-3(AQP-3) from Schistosoma japonicum(SJAQP-3) using bioinformalical methods,and to provid of references for vaccine targets research.Methods:Protparam,BepiPred,TMHMM Server,MLRC,Geno3d,DNA star software packages were used to predict the physical and chemical properties,hydrophilicity plot, flexibility regions,antigenic index,surface probability plot,secondary structure,and tertiary structure of amino acid sequence of SJAQP-3.Results:SJAQP-3 had six transmembrane regions and two half-spanning helices that form a central channel.The half-spanning helices fold into the centre of the channel.Either of the half-spanning helix had a conserved motif of NPA common to all aquaporins.Predicted linear B-Cell epitopes were most likely at the N-terminal amino acid residues of Saa-7aa,59aa- 62aa,225aa-230aa,282aa -288aa,294aa -29Saa and 305aa -307aa area.59aa- 62aa,22Saa-230aa located outside the membrane,the others located inside the cell.Conclusions:SJAQP-3 is a integral membrane protein in Schistosoma japonicum tegument.There are six potential epitopes in SJ AQP-3.It might be a potential molecular target for the development of vaccines.
文摘AIM:To search for further immunodominant peptides of the pyruvate dehydrogenase complex E2-component (PDC-E2) recognized by antimitochondrial antibodies (AMA) in primary biliary cirrhosis (PBC). METHODS:Sera from 95 patients with PBC were tested by enzyme-linked immunosorbent assay against 33 synthetic overlapping peptides (25 amino acids; aa) covering the entire length of the E2-subunit of PDC-E2. Furthermore,the inner lipoyl peptide 167-184 was used in an unlip oylated and a lipoylated form as well as coupled to ovalbumin. Sera from 11 AMA negative/ANA posit ive PBC patients,63 patients with other liver disorders and 22 healthy blood donors served as controls.RESULTS:Of the 95 PBC-sera,74% reacted with the peptide 475-499 and 58% with the pept ide 407-431 located within the catalytic domain of PDC-E2. Patients with other disorders or healthy controls were positive in only up to 18%. Antibodies to the unlipoylatedand lip oylated pept ide 167-184 within the inner lipoyl domain were found in only 5% and 11% of the PBC sera,respectively; using ovalbumin-coupled peptides,the incidence increased up to 57% (unlipoylated form). CONCLUSION:Peptides within the catalytic site of PDC-E2 rather than the previously reported lipoyl binding peptide 167-184 may represent major immunodomin ant epitopes recognized by AMA in PBC.
基金The National Natural Science Foundations of China (30870131)the National Key Projects in the Infectious Fields (2008ZX10002-011, 2008ZX10004-004)
文摘In recent years,the in silico epitopes prediction tools have facilitated the progress of vaccines development significantly and many have been applied to predict epitopes in viruses successfully. Herein,a general overview of different tools currently available,including T cell and B cell epitopes prediction tools,is presented. And the principles of different prediction algorithms are reviewed briefly. Finally,several examples are present to illustrate the application of the prediction tools.
文摘To compare the effects of polysaccharide nucleic acid fraction of bacillus calmette guerin (BCG PSN) and thymopeptides on T lymphocytes of normal and immunosuppressed mice, CD4 + and CD8 + T lymphocyte subsets of single nucleic cell in thymus, spleen and peripheral blood were detected successively by flow cytometry after application of BCG PSN and thymopeptides. Meanwhile, CD4 +/CD8 + ratio was also calculated. The results showed that both BCG PSN and thymopeptides could decrease the proportion of CD4 + CD8 + T lymphocyte subsets in the thymus, at the same time increase CD4 + T lymphocyte, CD8 +T lymphocyte proportion in the three tissues. The fluctuation in amplitude was greater in thymopeptides group than that in BCG PSN group. It is concluded that acting location of thymopeptides is in thymus, its stimulating action is stronger than that of BCG PSN, while BCG PSN not only accelerates the differentiation in thymus, but also has some direct stimulation to peripheral CD4 +T lymphocytes, and can maintain CD4 +/CD8 + ratio within normal range. So, BCG PSN is safer.
基金supported by the Finance Science and Technology Project of Hainan Province(ZDYF2018106,ZDXM2014069)the National Natural Science Foundation of China(81860373,51762012,81760376,81460306 and 31160030)+4 种基金the Education Department of Hainan Province(Hnky2019ZD-27)the National Innovation and Entrepreneurship Training Program for College Students(201511810007,201811810024)the Innovation and Entrepreneurship Training Program for College Students of Hainan Province(S201911810034)Innovation and Entrepreneurship Training Program for College Students of Hainan Medical University(HYCX2014013,HYCX2018024)Research Unit of Island Emergency Medicine of Chinese Academy of Medical Sciences(2019RU013).
文摘Objective:To predict B cell and T cell epitopes of 22-kDa,47-kDa,56-kDa and 58-kDa proteins.Methods:The sequences of 22-kDa,47-kDa,56-kDa and 58-kDa proteins which were derived from Orientia tsutsugamushi were analyzed by SOPMA,DNAstar,Bcepred,ABCpred,NetMHC,NetMHCⅡand IEDB.The 58-kDa tertiary structure model was built by MODELLER9.17.Results:The 22-kDa B-cell epitopes were located at positions 194-200,20-26 and 143-154,whereas the T-cell epitopes were located at positions 154-174,95-107,17-25 and 57-65.The 47-kD a protein B-cell epitopes were at positions 413-434,150-161 and 283-322,whereas the T-cell epitopes were located at positions 129-147,259-267,412-420 and 80-88.The 56-kDa protein B-cell epitopes were at positions 167-173,410-419 and 101-108,whereas the T-cell epitopes were located at positions 88-104,429-439,232-240 and 194-202.The 58-kDa protein B-cell epitopes were at positions 312-317,540-548 and 35-55,whereas the T-cell epitopes were located at positions 415-434,66-84 and 214-230.Conclusions:We identified candidate epitopes of 22-kDa,47-kDa,56-kDa and 58-kDa proteins from Orientia tsutsugamushi.In the case of 58-kDa,the dominant antigen is displayed on tertiary structure by homology modeling.Our findings will help target additional recombinant antigens with strong specificity,high sensitivity,and stable expression and will aid in their isolation and purification.
文摘BACKGROUND: The patient with malignant tumor always show immunologic function drawback and ingravescent with tumor development, especially in the aspect of cell-mediated immunity. This study was undertaken to define the relationship between the immune function of local cells and cancer development by investigating the distribution of natural killer (NK) cells and T-lymphocyte subsets in peripheral blood, the cancer tissue and the tissue surrounding gallbladder carcinoma. METHODS: The numbers of CD4(+) and CD8(+) T-lymphocytes and NK cells were measured by flow cytometry in samples taken from gallbladder cancer tissue, the surrounding tissues and peripheral blood of 38 patients, and compared with the numbers in the peripheral blood and gallbladder tissue of 30 patients with cholecystitis as controls. RESULTS: The numbers of CD4(+) and CD8(+) T-cells and NK cells in gallbladder cancer tissues were significantly higher than those in the surrounding tissue and gallbladder with gallstone. However, the ratio of CD4(+)/CD8(+) was lower in the cancer tissue than that in the surrounding tissue and tissue from gallbladders with gallstones. The distribution of CD4(+) and CD8(+) T-cells and NK cells in mucous membrane of cholecystitis gallbladder and that in the tissue surrounding gallbladder cancer were significantly different. CONCLUSIONS: Disproportionate and imbalanced distribution of NK cells and subsets of T-lymphocytes occurs in the mucous membrane proper of gallbladder cancer and surrounding tissue. Although gallbladder cancer tissue has higher expressions of CD4(+), CD8(+) and NK cells, the immune function is low or in an inhibited state. In gallbladder cancer immunization therapy, local cellular immunological function should be enhanced and the protective barrier improved.
基金Supported by A Grant from the Spanish Ministry of Health and Consumer Affairs,No. FIS PS09/00899 and SAF 2009-10403CIBERehd Funded by Instituto CarlosⅢ,Ministry of Health and Consumer Affairs
文摘AIM:To investigate the variability of the main immunodominant motifs of hepatitis B virus(HBV) core gene by ultra-deep-pyrosequencing(UDPS).METHODS:Four samples(2 genotype A and 2 genotype D) from 4 treatment-na ve patients were assessed for baseline variability.Two additional samples from one patient(patient 4,genotype D) were selected for analysis:one sample corresponded to a 36-mo treatment-free period from baseline and the other to the time of viral breakthrough after 18 mo of lamivudine treatment.The HBV region analyzed covered amino acids 40 to 95 of the core gene,and included the two main epitopic regions,Th50-69 and B74-84.UDPS was carried out in the Genome Sequencer FLX system(454 Life Sciences,Roche).After computer filtering of UDPS data based on a Poisson statistical model,122 813 sequences were analyzed.The most conserved position detected by UDPS was analyzed by site-directed mutagenesis and evaluated in cell culture.RESULTS:Positions with highest variability rates were mainly located in the main core epitopes,confirming their role as immune-stimulating regions.In addition,the distribution of variability showed a relationship with HBV genotype.Patient 1(genotype A) presented the lowest variability rates and patient 2(genotype A) had 3 codons with variability higher than 1%.Patient 3 and 4(both genotype D) presented 5 and 8 codons with variability higher than 1%,respectively.The median baseline frequencies showed that genotype A samples had higher variability in epitopic positions than in the other positions analyzed,approaching significance(P = 0.07,sample 1 and P = 0.05,sample 2).In contrast,there were no significant differences in variability between the epitopic and other positions in genotype D cases.Interestingly,patient 1 presented a completely mutated motif from amino acid 64 to 67(E 64 LMT 67),which is commonly recognized by T helper cells.Additionally,the variability observed in all 4 patients was particularly associated with the E 64 LMT 67 motif.Codons 78 and 79 were highly conserved in all samples,in keeping with their involvement in the interaction between the HBV virion capsid and the surface antigens(HBsAg).Of note,codon 76 was even more conserved than codons 78 and 79,suggesting a possible role in HBsAg interactions or even in hepatitis B e antigen conformation.Sequential analysis of samples from patient 4(genotype D) illustrated the dynamism of the HBV quasispecies,with strong selection of one minor baseline variant coinciding with a decrease in core variability during the treatment-free and lamivudinetreated period.The drop in variability seemed to result from a "steady state" situation of the HBV quasispecies after selection of the variant with greatest fitness.CONCLUSION:Host immune pressure seems to be the main cause of HBV core evolution.UDPS analysis is a useful technique for studying viral quasispecies.
文摘Objective: To investigate the potential and early effect of hypertonic saline resuscitation on T-lymphocyte sub- populations in rats with hemorrhagic shock. Methods: A model of rat with severe hemorrhagic shock was established in 18 Sprague-Dawley (SD) rats. The rats were randomly divided into Sham group, HTS group (hypertonic saline resuscitation group) and NS group (normal saline resuscitation group). Each group contained 6 rats. The CD4+ and CD8+ subpopulations of T-lymphocytes in peripheral blood were detected respectively before shock and after resuscitation by double antibody labelling and flow cytometry. Results: In the early stage after hemorrhagic shock, fluid resuscitation and emergency treatment, the CD4+ lymphocytes of peripheral blood in HTS and NS groups markedly increased. Small volume resuscitation with HTS also induced peripheral CD8+ lymphocytes to a certain extent, whereas NS resuscitation showed no effect in this respect. Consequently, compared with Sham and HTS groups, CD4+/CD8+ ratio of peripheral blood in NS group was obviously increased, and showed statistically differences. Conclusion: In this model of rat with severe hemorrhagic shock, small volume resuscitation with HTS is more effective than NS in reducing immunologic disorders and promoting a more balanced profile of T-lymphocyte subpopula- tions regulating network.
文摘AIM: To investigate peripheral T-lymphocyte sub-population profile and its correlation with hepatitis B virus (HBV) replication in patients with chronic hepatitis B (CHB).METHODS: Distribution of T-lymphocyte subpopulations in peripheral blood was measured by flow cytometry in 206 CHB patients. HBV markers were detected with ELISA. Serum HBV DNA load was assessed with quantitative real-time polymerase chain reaction (PCR). The relationship between HBV replication and variation in peripheral T-cell subsets was analyzed.RESULTS: CHB patients had significantly decreased CD3+ and CD4+ cells and CD4+/CD8+ ratio, and increased CD8+ cells compared with uninfected controls (55.44 ± 12.39 vs 71.07 ± 4.76, 30.92 ± 7.48 vs 38.94 ± 3.39, 1.01 ± 0.49 vs 1.67 ± 0.33, and 34.39 ± 9.22 vs 24.02 ± 4.35; P < 0.001, respectively). Univariate analysis showed a similar pattern of these parameters was significantly associated with high viral load, presence of serum hepatitis B e antigen (HBeAg) expression, liver disease severity, history of maternal HBV infection, and young age at HBV infection, all with P < 0.01. There was a significant linear relationship between viral load and these parameters of T-lymphocyte subpopulations (linear trend test P < 0.001). There was a negative correlation between the levels of CD3+ and CD4+ cells and CD4+/CD8+ ratio and serum level of viral load in CHB patients (r = -0.68, -0.65 and -0.75, all P < 0.0001), and a positive correlation between CD8+ cells and viral load (r = 0.70, P < 0.0001). There was a significant decreasing trend in CD3+ and CD4+ cells and CD4+/CD8+ ratio with increasing severity of hepatocyte damage and decreasing age at HBV infection (linear trend test P < 0.01). In multiple regression (after adjustment for age at HBV infection, maternal HBV infection status and hepatocyte damage severity) log copies of HBV DNA maintained a highly significant predictive coefficient on T-lymphocyte subpopulations, and was the strongest predictor of variation in CD3+, CD4+, CD8+ cells and CD4+/CD8+ ratio. However, the effect of HBeAg was not significant.CONCLUSION: T-lymphocyte failure was signifi-cantly associated with viral replication level. The substantial linear dose-response relationship and strong independent predictive effect of viral load on T-lymphocyte subpopulations suggests the possibility of a causal relationship between them, and indicates the importance of viral load in the pathogenesis of T cell hyporesponsiveness in these patients.
文摘AIM: To assess the three polymorphJsm regions within cytotoxic T-lymphocyte antigen 4 (CTLA-4) gene, a C/T base exchange in the promoter region-318 (CTLA-4 -318C/T), an A/G substitution in the exon 1 position 49 (CTLA-4 49A/G), a T/C substitution in 1172 (CTLA-4 -1172T/C) in patients with chronic hepatitis B. METHODS: Fifty-one patients with chronic hepatitis B virus infection and 150 healthy subjects were recruited sequentially as they presented to the hepatic clinic. Classification of chronic hepatitis B virus (HBV)-infected patients was as asymptomatic carrier state (26 patients) and chronic hepatitis B (25 patients). Genomic DNA was isolated from anti-coagulated peripheral blood Bully coat using Miller's salting-out method. The presence of the CTLA-4 gene polymorphisms was determined using polymerase chain reaction amplification refractory mutation system (ARMS). RESULTS: We observed a significant association between -318 genotypes frequency (T+C-, T+C+, T-C+) and susceptibility to chronic hepatitis B (P=0.012, OR=0.49, 95%CI: 0.206-1.162). However, we did not observe a significant association for +49 genotype frequency (T+C+, T+C- T-C+) and -1172 genotype frequency (C+T+, T+C- C+T-) and state of disease. CONCLUSION: Our results suggest that CTLA-4 gene polymorphisms may partially be involved in the susceptibility to chronic hepatitis B.
文摘AIM:To investigate the peripheral T-lymphocyte subpopulation profile,and its correlations with hepatitis B virus(HBV) replication level in chronic HBV-infected(CHI) individuals with normal liver function tests(LFTs) . METHODS:Frequencies of T-lymphocyte subpopu-lations in peripheral blood were measured by flow cytometry in 216 CHI individuals. HBV markers were detected with ELISA. Serum HBV DNA load was assessed with quantitative real-time PCR. Information of age at HBV infection,and maternal HBV infection status was collected. ANOVA linear trend test and linear regression were used in statistical analysis. RESULTS:CHI individuals had significantly decreased relative frequencies of CD3+,CD4+ subpopulationsand CD4+/CD8+ ratio,and increased CD8+ subset percentage compared with uninfected individuals(all P < 0.001) . There was a significant linear relationship between the load of HBV DNA and the parameters of T-lymphocyte subpopulations(ANOVA linear trend test P < 0.01) . The parameters were also significantly worse among individuals whose mothers were known to be HBV carriers,and those having gained infection before the age of 8 years. In multiple regressions,after adjustment for age at HBV infection and status of maternal HBV infection,log copies of HBV DNA maintained its highly significant predictive coefficient on T-lymphocyte subpopulations,whereas the effect of HBeAg was not significant. CONCLUSION:HBV DNA correlates with modification in the relative T-lymphocyte subpopulation frequencies. High viral load is more powerful than HBeAg in predicting the impaired balance of T-cell subsets.
文摘In this study, the coding region of type O FMDV capsid protein VP1 and a series of codon optimized DNA sequences coding for VP1 amino acid residues 141-160 (epitopel), tandem repeat 200-213 (epitope2 (+2)) and the combination of two epitopes (epitopel-2) was genetically cloned into the prokaryotic expression vector PPRoExHTb and pGEX4T-1, respectively. VP1 and the fused epitopes GST-E1, GST-E2 (+2) and GST-E1-2 were successfully solubly expressed in the cytoplasm of Escherichia coli and Western blot analysis demonstrated they retained antigenicity. Indirect VP1-ELISA and epitope ELISAs were subsequently developed to screen a panel of 80 field pig sera using LPB-ELISA as a standard test. For VP1-ELISA and all the epitope ELISAs, there were clear distinctions between the FMDV-positive and the FMDV-negative samples. Cross-reactions with pig sera positive to the viruses of swine vesicular disease virus that produce clinically indistinguishable syndromes in pigs or guinea pig antisera to FMDV strains of type A, C and Asia1 did not occur. The relative sensitivity and specificity for the GST-E1 ELISA, GST-E2 (+2), GST-E1-2 ELISA and VP1-ELISA in comparison with LPB-ELISA were 93.3% and 85.0%, 95.0% and 90%, 100% and 81.8%, 96.6% and 80.9% respectively. This study shows the potential use of the aforementioned epitopes as alternatives to the complex antigens used in current detection for antibody to FMDV structural proteins.
文摘Study Objective: To observe the effect of dexmedetomidine (DEX) on T-lymphocyte subsets and natural killer (NK) cells in the peripheral blood of perioperative patients with colorectal cancer. Design: A random double-blind control clinical study. Setting: A university hospital. Patients: Forty patients with colorectal cancer, ASA I-П. Interventions: All patients were randomly divided into a DEX group (n = 20) and a control group (n = 20). Before induction of anesthesia, epidural catheters were placed in the L1-L2 or T12-L1 intervertebral spaces. The DEX group received 1 μg/kg of DEX (200 μg/50 ml) intravenously for 15 min prior to the surgery, which was then infused at a rate of 0.5 μg/kg/h until 30 min before the end of the surgery. The control group received an intravenous infusion of saline (50 ml) instead of DEX during the same periods as the DEX group. All patients received routine anesthesia and postoperative analgesia. Measurements: Blood samples from all patients were collected at the following time points: before anesthesia (T0), 24 h after surgery (T1), 48 h after surgery (T2) and 72 h after surgery (T3). Changes in T-lymphocyte subsets (CD3+, CD4+, CD8+, CD4+/CD8+) and NK cells were determined by flow cytometry. Main Results: Compared with the control group, the percentages of CD3+ and CD4+ cells and the CD4+/CD8+ ratio in the DEX group increased significantly from T1 to T3
文摘The major envelope glycoprotein E of dengue (DEN) virus plays a central role in the biology of flaviviruses. It is capable of inducing a protective immune response in vivo and responsible for the viral binding to the cellular receptor. The crystal structures of glycoprotein E ectodomains have already been determined. However, it is still un-clear where the well-defined B-cell epitopes for glycoprotein E which induce the neutralizing an-tibodies locates. Thus, in order to characterize the role of glycoprotein E in the pathogenesis of dengue virus infection, we first used network servers (http://bio.dfci. harvard.edu/Tools/ &amp;http://www. imtech. res. in) to predict and analyze the well defined B-cell and T-cell epitopes of the glycoprotein of the DEN-1 HAWAII strain. Then based on the highly conserved envelop glyco-protein amino acids, the hydrophilicity, antigenic-ity, accessibility and flexibility of envelop glyco-protein E were further predicted by using Biotic softwares (DNASTAR) and network servers (http://bio. dfci.harvard.edu/Tools/), the secondary structure was putatively obtained. In our study, the sequence at 281-295 amino acid (aa) for den-gue virus type 1 HAWAII strain and the sequence at 345-359, 383-397 for dengue virus type 2 NGC strain were predicted as the more prevalent epi-topes by using multiple parameters and different analysis softwares, respectively. Two epitopes of DEN-2 and one of DEN-1 locate on the domain Ш and domainⅡ of the protein E, respectively. Sub-sequently, further studies will be carried out to examine the antigenicity and protection of the synthetic peptides with higher scores in the av-erage antigen index (AI) and better hydrophilic properties determined by our data.