Objective:To investigate Phlebotomus(P.)sergenti Parrot,1917(Diptera:Psychodidae)salivary gland antigens and their immune response in human.Methods:Human volunteers were exposed to sand flies’bites in the laboratory,...Objective:To investigate Phlebotomus(P.)sergenti Parrot,1917(Diptera:Psychodidae)salivary gland antigens and their immune response in human.Methods:Human volunteers were exposed to sand flies’bites in the laboratory,and following each exposure the size of induration was recorded.The mean protein concentration of salivary gland lysate and specific anti-P.sergenti saliva IgG was measured.Sand fly salivary proteins were separated by SDS-PAGE and their immunoreactivity was examined by Western blotting assays.Results:Individuals exposed to P.sergenti salivary gland lysate for 8 months showed both antibody and delayed type hypersensitivity responses,although exposure for one month did not provoke any immune responses.The trend of antibody fluctuated during the exposure time and dropped by the end of antigen loading.The mean protein content was(0.36±0.08)μg in each pair salivary glands.Salivary gland lysate showed 11 to 12 major protein bands and 3 to 6 of them were immunoreactive.Conclusions:Our study showed that the salivary gland components of P.sergenti provoked both cellular and humoral immune responses in human.Furthermore,there are some immunogenic proteins in P.sergenti saliva which could be subjected for further investigation as vector-based vaccine candidate/s against anthroponotic cutaneous leishmaniasis.展开更多
AIM: To describe human leukocyte antigen(HLA) alleles in individuals with Down syndrome and alopecia areata. METHODS: A cross-sectional study was conducted, which evaluated 109 individuals. Ten with down syndrome(DS) ...AIM: To describe human leukocyte antigen(HLA) alleles in individuals with Down syndrome and alopecia areata. METHODS: A cross-sectional study was conducted, which evaluated 109 individuals. Ten with down syndrome(DS) and alopecia areata(AA), ten with DS without AA and ten with AA without DS, and their fami-lies. The individuals were matched by gender and age. The following data were computed: gender, age, ethnic group, karyotype, clinical presentation and family history of alopecia areata. Descriptive analysis: measures of central tendency and frequency distribution. Inferential analysis: Fisher's exact test to compare categorical data between the three groups and Kruskal-Wallis ANOVA test for numerical data.RESULTS: Seventy per cent of evaluated individuals in the DS and AA group were male; presented mean age of 18.6(SD ± 7.2) years and 70% were Caucasian. We observed involvement of the scalp, with a single lesion in 10% and multiple in 90% of subjects. It was observed that there is no significant difference in the frequency distributions of the alleles HLA loci A, B, C, DRB1 and DQB1 of subjects studied. However, according to Fisher's exact test, there is a trend(P = 0.089) of DS group to present higher proportions of HLA-A 36 and HLA-B 15 than the AA group and AA and DS group.CONCLUSION: There was a tendency for the DS group, to present proportion of HLA-A 36 and HLA-B 15 higher than the AA group and group of individuals with AA and DS. However, there was no significant difference in the frequency distribution of the alleles.展开更多
Human African trypanosomiasis (HAT) affects up to half a million people every year in sub-Saharan Africa. Interruption of transmission of the disease by early diagnosis and treatment is core to the control and eventua...Human African trypanosomiasis (HAT) affects up to half a million people every year in sub-Saharan Africa. Interruption of transmission of the disease by early diagnosis and treatment is core to the control and eventual elimination of HAT. The routine diagnostic method for HAT is light microscopy of blood samples. The present study sought to evaluate the potential of TbgI2 and TbgI17 tandem repeat antigens as candidates for the diagnosis of Trypanosoma brucei rhodesiense. The expressed proteins were purified and the antigenic reactivity evaluation was done using multiplex assay using sera obtained from HAT patients. Receiver operating characteristic analysis showed that recombinant antigen, TbgI2 had high sensitivity for sera from patients infected with T. b. rhodesiense with the area under the curve being 0.577 and a sensitivity of 0.641 and specificity 0.650. The results suggest that TbgI2 is a potential biomarker for T. b. rhodesiense HAT serodiagnostic tests.展开更多
BACKGROUND Antibody-mediated rejection following liver transplantation(LT)has been increasingly recognized,particularly with respect to the emergence of de novo donor-specific antibodies(DSAs)and their impact on graft...BACKGROUND Antibody-mediated rejection following liver transplantation(LT)has been increasingly recognized,particularly with respect to the emergence of de novo donor-specific antibodies(DSAs)and their impact on graft longevity.While substantial evidence for adult populations exists,research focusing on pediatric LT outcomes remains limited.AIM To investigate the prevalence of human leukocyte antigen(HLA)mismatches and DSA and evaluate their association with rejection episodes after pediatric LT.METHODS A cohort of pediatric LT recipients underwent HLA testing at Santa Casa de Porto Alegre,Brazil,between December 2013 and December 2023.Only patients who survived for>30 days after LT with at least one DSA analysis were included.DSA classes I and II and cross-matches were analyzed.The presence of de novo DSA(dnDSA)was evaluated at least 3 months after LT using the Luminex®single antigen bead method,with a positive reaction threshold set at 1000 MFI.Rejection episodes were confirmed by liver biopsy.RESULTS Overall,67 transplanted children were analyzed;61 received grafts from living donors,85%of whom were related to recipients.Pre-transplant DSA(class I or II)was detected in 28.3%of patients,and dnDSA was detected in 48.4%.The median time to DSA detection after LT was 19.7[interquartile range(IQR):4.3-35.6]months.Biopsyproven rejection occurred in 13 patients at follow-up,with C4d positivity observed in 5/13 Liver biopsies.The median time to rejection was 7.8(IQR:5.7-12.8)months.The presence of dnDSA was significantly associated with rejection(36%vs 3%,P<0.001).The rejection-free survival rates at 12 and 24 months were 76%vs 100%and 58%vs 95%for patients with dnDSA anti-DQ vs those without,respectively.CONCLUSION Our findings highlight the importance of incorporating DSA assessment into pre-and post-transplantation protocols for pediatric LT recipients.Future implications may include immunosuppression minimization strategies based on this analysis in pediatric LT recipients.展开更多
Background and Aims:Hepatitis B virus(HBV)infection is a major risk factor for cirrhosis and liver cancer,and its treatment continues to be difficult.We previously demonstrated that a dopamine analog inhibited the pac...Background and Aims:Hepatitis B virus(HBV)infection is a major risk factor for cirrhosis and liver cancer,and its treatment continues to be difficult.We previously demonstrated that a dopamine analog inhibited the packaging of pregenomic RNA into capsids.The present study aimed to determine the effect of dopamine on the expressions of hepatitis B virus surface and e antigens(HBsAg and HBeAg,respectively)and to elucidate the underlying mechanism.Methods:We used dopamine-treated HBVinfected HepG2.2.15 and NTCP-G2 cells to monitor HBsAg and HBeAg expression levels.We analyzed interferon-stimulated gene 15(ISG15)expression in dopamine-treated cells.We knocked down ISG15 and then monitored HBsAg and HBeAg expression levels.We analyzed the expression of Janus kinase(JAK)/signal transducer and activator of transcription(STAT)pathway factors in dopamine-treated cells.We used dopamine hydrochloride-treated adeno-associated virus/HBV-infected mouse model to evaluate HBV DNA,HBsAg,and HBeAg expression.HBV virus was collected from HepAD38.7 cell culture medium.Results:Dopamine inhibited HBsAg and HBeAg expression and upregulated ISG15 expression in HepG2.2.15 and HepG2-NTCP cell lines.ISG15 knockdown increased HBsAg and HBeAg expression in HepG2.2.15 cells.Dopamine-treated cells activated the JAK/STAT pathway,which upregulated ISG15 expression.In the adeno-associated virus-HBV murine infection model,dopamine downregulated HBsAg and HBeAg expression and activated the JAK-STAT/ISG15 axis.Conclusions:Dopamine inhibits the expression of HBsAg and HBeAg by activating the JAK/STAT pathway and upregulating ISG15 expression.展开更多
Background Humoral immunity is an important factor for long-term survival of renal allograft. Here we performed a four-year follow-up to explore the clinical significance of monitoring anti-human leukocyte antigens (...Background Humoral immunity is an important factor for long-term survival of renal allograft. Here we performed a four-year follow-up to explore the clinical significance of monitoring anti-human leukocyte antigens (HLA) and anti-major histocompatibility complex class I-related chain A (MICA) antibody expression after kidney transplantation. Methods We obtained serial serum samples from 84 kidney transplant patients over a four-year period. All patients were followed up at least 6 months after transplantation and had at least two follow-up points. Anti-HLA and anti-MICA antibody titres and serum creatinine (SCr) levels were evaluated at each follow-up. Patients were divided into 4 groups: HLA(+) MICA(-), HLA(-)MICA(+), HLA(+)MICA(+) and HLA(-)MICA(-). The impact of post-transplant antibody level on kidney allograft function was evaluated. Results Antibodies were detected in 38.1% (32/84) of the renal allograft recipients. HLA, MICA and HLA+MICA expression was observed in 18.89%, 14.44% and 5.93% of the recipients respectively. The most frequent anti-HLA and anti-MICA specific antibodies identified were All, A24, A29, A32, A33, A80; B7, B13, B37; DR17, DR12, DR18, DR52, DR53, DR1, DR4, DR9, DR51; DQ7, DQ4, DQ8, DQ2, DQ9, DQ5, DQ6 and MICA02, MICA18, MICA19, MICA07, MICA27. As the time after transplantation elapsed, more recipients developed de novo antibody expression. Total 11.91% (10/84) of the recipients had de novo antibody expression during the follow up. The average level of SCr and the percentage of recipients with abnormal allograft function were significantly higher in recipients with anti-HLA and/or anti- MICA antibody expression than those without. The appearance of anti-HLA and anti-MICA antibody expression always preceded the increase in SCr value. Conclusions Anti-HLA and anti-MICA antibody expression has predictive value for early and late allograft dysfunction. The presence of donor specific antibody is detrimental to graft function and graft survival.展开更多
Neuromyelitis optica(NMO)is an autoimmune demyelinating disorder,predominantly characterized by severe optic neuritis,transverse myelitis and the high level of antibodies against aquaporin-4(AQP4)or NMO-immunoglobulin...Neuromyelitis optica(NMO)is an autoimmune demyelinating disorder,predominantly characterized by severe optic neuritis,transverse myelitis and the high level of antibodies against aquaporin-4(AQP4)or NMO-immunoglobulin G(IgG).Researches trying to correlate NMO with specific human leukocyte antigen(HLA)alleles took place in a limited extend in the last few years.Nevertheless,it has become clear that HLAs play a crucial role in the genetic risk of NMO,in the understanding of its pathogenesis and the differential diagnosis mainly from multiple sclerosis(MS),and also from other demyelinating diseases.In this study,we retrieved all the available data in the MEDLINE concerning the distribution of HLA frequencies in NMO and NMO-spectrum diseases,in all available ethnic groups,and compared them with those of MS.The results suggest that,the well-established HLA-DRB1*15:01 allele,associated with MS,plays rather a protective role for NMO.HLA-DRB1*03 allele is highly frequent in the NMO-IgG positive Caucasian patients,while HLA-DPB1*05:01 is the predominant allele in Japanese patients.The HLA-genotype and anti-AQP4 presence are the common immunological components in cases of comorbidity of NMO and other autoimmune diseases.The authors aim to summarize in the critical review the results of these researches worldwide,create a workable table including all this information for an easier reading approach and highlight the importance of these results in therapeutic decision making,using the HLA profile as biomarker in patients’stratification.展开更多
Tumor-specific antigens or neoantigens are peptides that are expressed only in cancer cells and not in healthy cells.Some of these molecules can induce an immune response,and therefore,their use in immunotherapeutic s...Tumor-specific antigens or neoantigens are peptides that are expressed only in cancer cells and not in healthy cells.Some of these molecules can induce an immune response,and therefore,their use in immunotherapeutic strategies based on cancer vaccines has been extensively explored.Studies based on these approaches have been triggered by the current high-throughput DNA sequencing technologies.However,there is no universal nor straightforward bioinformatic protocol to discover neoan-tigens using DNA sequencing data.Thus,we propose a bioinformatic protocol to detect tumor-specific antigens associated with single nucleotide variants(SNVs)or“mutations”in tumoral tissues.For this purpose,we used publicly available data to build our model,including exome sequencing data from colorectal cancer and healthy cells obtained from a single case,as well as frequent human leukocyte antigen(HLA)class I alleles in a specific population.HLA data from Costa Rican Central Valley population was selected as an example.The strategy included three main steps:(1)pre-processing of sequencing data;(2)variant calling analysis to detect tumor-specific SNVs in comparison with healthy tissue;and(3)prediction and characterization of peptides(protein fragments,the tumor-specific antigens)derived from the variants,in the context of their affinity with frequent alleles of the selected population.In our model data,we found 28 non-silent SNVs,present in 17 genes in chromosome one.The protocol yielded 23 strong binders peptides derived from the SNVs for frequent HLA class I alleles for the Costa Rican population.Although the analyses were performed as an example to implement the pipeline,to our knowledge,this is the first study of an in silico cancer vaccine using DNA sequencing data in the context of the HLA alleles.It is concluded that the standardized protocol was not only able to identify neoantigens in a specific but also provides a complete pipeline for the eventual design of cancer vaccines using the best bioinformatic practices.展开更多
Objective From the ancient period cow’urine has been used as a medicine. In Veda, cow’urine was compared to the nectar. In Susrut, several medicinal properties of cow’ urine have been mentioned and are known to ca...Objective From the ancient period cow’urine has been used as a medicine. In Veda, cow’urine was compared to the nectar. In Susrut, several medicinal properties of cow’ urine have been mentioned and are known to cause weight loss, reversal of certain cardiac and kidney problems, indigestion, stomach ache, edema, etc. However, the literature and scripture did not mention the antigenotoxic properties of cow’urine. Methods In the present investigation, the antigenotoxic/ antioxidant properties of cow’ urine distillate and redistillate were studied in vitro. The antioxidant status and volatile fatty acid levels were determined. Actinomycin-D (0.1ol/L) and hydrogen peroxide (150 mol/L) were used for inducing DNA strand break with 0.1% DMSO as negative control. Dose for the antigenotoxic effect of cow’ urine was chosen from the dose response study carried out earlier. Results Both actinomycin-D and H2O2 caused statistically significant DNA unwinding of 80% & 75% respectively (P<0.001) as revealed by fluorimetric analysis of DNA unwinding (FADU), and the damage could be protected with the redistilled cow urine distillate (1, 50 & 100 ) in simultaneous treatment with genotoxic chemicals. Conclusion The redistillate of cowurine was found to possess total antioxidant status of around 2.6 mmol, contributed mainly by volatile fatty acids (1500 mg/L) as revealed by the GC-MS studies. These fatty acids and other antioxidants might cause the observed protective effects.展开更多
Many mechanisms have been proposed to explain the hypothetical state of hepatic tolerance,which is described by eventual imbalances or deregulation in the balance of cytokines,mediators,effectors,and regulatory cells ...Many mechanisms have been proposed to explain the hypothetical state of hepatic tolerance,which is described by eventual imbalances or deregulation in the balance of cytokines,mediators,effectors,and regulatory cells in the complex milieu of the liver.In this section,we will comment on the importance of donorspecific anti-human leukocyte antigen(HLA)antibodies(DSA)as well as the compatibility and pairings of HLA and killer-cell immunoglobulin-like receptor(KIR)genotypes in the evolution of liver transplantation.Thus,HLA compatibility,viral infections,and HLA-C/KIR combinations have all been linked to liver transplant rejection and survival.There have been reports of increased risk of acute and chronic rejection with ductopenia,faster graft fibrosis,biliary problems,poorer survival,and even de novo autoimmune hepatitis when DSAs are present in the recipient.Higher mean fluorescence intensity(MFI)values of the DSAs and smaller graft size were associated with poorer patient outcomes,implying that high-risk patients with preformed DSAs should be considered for selecting the graft placed and desensitization methods,according to the investigators.Similarly,in a combined kidney-liver transplant,a pretransplant with a visible expression of several DSAs revealed that these antibodies were resistant to treatment.The renal graft was lost owing to antibody-mediated rejection(AMR).The HLA antigens expressed by the transplanted liver graft influenced antibody elimination.Pathologists are increasingly diagnosing AMR in liver transplants,and desensitization therapy has even been employed in situations of AMR,particularly in patients with DSAs in kidney-hepatic transplants and high-class II MFI due to Luminex.In conclusion,after revealing the negative impacts of DSAs with high MFI,pretransplant virtual crossmatch techniques may be appropriate to improve evolution;however,they may extend cold ischemia periods by requiring the donor to be typed.展开更多
(2′-5′) oligoadenylate (2-5 A) synthetase is a key enzyme in the establishment of the antiviral and antieetlular states caused by interferon. 2-5 A synthesized by the enzyme is capable of activating a cellular laten...(2′-5′) oligoadenylate (2-5 A) synthetase is a key enzyme in the establishment of the antiviral and antieetlular states caused by interferon. 2-5 A synthesized by the enzyme is capable of activating a cellular latent endonuclease (RNase L ), leading to the degradation of viral mRNA and cellular rRNA, and inhibiting viral replicatio and cellular proliferation, The level of 2-5 A synthetase in human leukocytes could be enhanced during virus infection or展开更多
The potential of the skin immune system to generate immune responses is well established, and the skin is actively exploited as a vaccination site. Human skin contains several antigen-presenting cell subsets with spec...The potential of the skin immune system to generate immune responses is well established, and the skin is actively exploited as a vaccination site. Human skin contains several antigen-presenting cell subsets with specialized functions. In particular, the capacity to cross-present exogenous antigens to CD8^+ T cells is of interest for the design of effective immunotherapies against viruses or cancer. Here, we show that primary human Langerhans cells (LCs) were able to cross-present a synthetic long peptide (SLP) to CD8^+ T cells. In addition, modification of this SLP using antibodies against the receptor langerin, but not dectin-1, further enhanced the cross-presenting capacity of LCs through routing of internalized antigens to less proteolytic early endosome antigen 1 ^+ early endosomes. The potency of LCs to enhance CD8^+ T-cell responses could be further increased through activation of LCs with the toll-like receptor 3 ligand polyinosinic:polycytidylic acid (phC). Altogether, the data provide evidence that human LCs are able to cross-present antigens after langerin-mediated internalization. Furthermore, the potential for antigen modification to target LCs specifically provides a rationale for generating effective anti-tumor or anti-viral cytotoxic T lymphocyte responses.展开更多
AIM: To evaluate the level of sperm chromosome aberrations in male patients with hepatitis B, and to directly detect whether there are HBV DNA integrations in sperm chromosomes of hepatitis B patients.METHODS: Sperm c...AIM: To evaluate the level of sperm chromosome aberrations in male patients with hepatitis B, and to directly detect whether there are HBV DNA integrations in sperm chromosomes of hepatitis B patients.METHODS: Sperm chromosomes of 14 tested subjects (5healthy controls, 9 patients with HBV infection, including 1with acute hepatitis B, 2 with chronic active hepatitis B, 4with chronic persistent hepatitis B, 2 chronic HBsAg carriers with no clinical symptoms) were prepared using interspecific in vitro fertilization between zona-free golden hamster ova and human spermatozoa, and the frequencies of aberration spermatozoa were compared between subjects of HBV infection and controls. Fluorescence in situ hybridization (FISH) to sperm chromosome spreads was carried out with biotin-labeled full length HBV DNA probe to detect the specific HBV DNA sequences in the sperm chromosomes.RESULTS: The total frequency of sperm chromosome aberrations in HBV infection group (14.8%, 33/223) was significantly higher than that in the control group (4.3%,5/116). Moreover, the sperm chromosomes in HBV infection patients commonly presented stickiness, clumping, failure to staining, etc, which would affect the analysis of sperm chromosomes. Specific fluorescent signal spots for HBV DNA were seen in sperm chromosomes of one patient with chronic persistent hepatitis. In 9 (9/42) sperm chromosome complements containing fluorescent signal spots, one presented 5 obvious FISH spots, others presented 2 to 4signals. There was significant difference of fluorescence intensity among the signal spots. The distribution of signal sites among chromosomes was random.CONCLUSION: HBV infection can bring about mutagenic effects on sperm chromosomes. Integrations of viral DNA into sperm chromosomes which are multisites and nonspecific, can further increase the instability of sperm chromosomes. This study suggested that HBV infection can create extensively hereditary effects by alteration genetic constituent and/or induction chromosome aberrations, as well as the possibility of vertical transmission of HBV via the germ line to the next generation.展开更多
基金a part of project that was financially supported by School of Public Health,Tehran University of Medical sciences(TUMS),(Proj.No.95-02-27-31419)the center for research and training in skin diseases and leprosy.
文摘Objective:To investigate Phlebotomus(P.)sergenti Parrot,1917(Diptera:Psychodidae)salivary gland antigens and their immune response in human.Methods:Human volunteers were exposed to sand flies’bites in the laboratory,and following each exposure the size of induration was recorded.The mean protein concentration of salivary gland lysate and specific anti-P.sergenti saliva IgG was measured.Sand fly salivary proteins were separated by SDS-PAGE and their immunoreactivity was examined by Western blotting assays.Results:Individuals exposed to P.sergenti salivary gland lysate for 8 months showed both antibody and delayed type hypersensitivity responses,although exposure for one month did not provoke any immune responses.The trend of antibody fluctuated during the exposure time and dropped by the end of antigen loading.The mean protein content was(0.36±0.08)μg in each pair salivary glands.Salivary gland lysate showed 11 to 12 major protein bands and 3 to 6 of them were immunoreactive.Conclusions:Our study showed that the salivary gland components of P.sergenti provoked both cellular and humoral immune responses in human.Furthermore,there are some immunogenic proteins in P.sergenti saliva which could be subjected for further investigation as vector-based vaccine candidate/s against anthroponotic cutaneous leishmaniasis.
文摘AIM: To describe human leukocyte antigen(HLA) alleles in individuals with Down syndrome and alopecia areata. METHODS: A cross-sectional study was conducted, which evaluated 109 individuals. Ten with down syndrome(DS) and alopecia areata(AA), ten with DS without AA and ten with AA without DS, and their fami-lies. The individuals were matched by gender and age. The following data were computed: gender, age, ethnic group, karyotype, clinical presentation and family history of alopecia areata. Descriptive analysis: measures of central tendency and frequency distribution. Inferential analysis: Fisher's exact test to compare categorical data between the three groups and Kruskal-Wallis ANOVA test for numerical data.RESULTS: Seventy per cent of evaluated individuals in the DS and AA group were male; presented mean age of 18.6(SD ± 7.2) years and 70% were Caucasian. We observed involvement of the scalp, with a single lesion in 10% and multiple in 90% of subjects. It was observed that there is no significant difference in the frequency distributions of the alleles HLA loci A, B, C, DRB1 and DQB1 of subjects studied. However, according to Fisher's exact test, there is a trend(P = 0.089) of DS group to present higher proportions of HLA-A 36 and HLA-B 15 than the AA group and AA and DS group.CONCLUSION: There was a tendency for the DS group, to present proportion of HLA-A 36 and HLA-B 15 higher than the AA group and group of individuals with AA and DS. However, there was no significant difference in the frequency distribution of the alleles.
文摘Human African trypanosomiasis (HAT) affects up to half a million people every year in sub-Saharan Africa. Interruption of transmission of the disease by early diagnosis and treatment is core to the control and eventual elimination of HAT. The routine diagnostic method for HAT is light microscopy of blood samples. The present study sought to evaluate the potential of TbgI2 and TbgI17 tandem repeat antigens as candidates for the diagnosis of Trypanosoma brucei rhodesiense. The expressed proteins were purified and the antigenic reactivity evaluation was done using multiplex assay using sera obtained from HAT patients. Receiver operating characteristic analysis showed that recombinant antigen, TbgI2 had high sensitivity for sera from patients infected with T. b. rhodesiense with the area under the curve being 0.577 and a sensitivity of 0.641 and specificity 0.650. The results suggest that TbgI2 is a potential biomarker for T. b. rhodesiense HAT serodiagnostic tests.
基金approved by the Ethics and Research Committee of the Federal University of Health Sciences of Porto Alegre(UFCSPA)and the Santa Casa de Misericórdia de Porto Alegre Complex(ISCMPA)(approval numbers 3805918 and 3938979,respectively)the Brazilian Clinical Trials Registry(ReBec)under number RBR-3 gtcvjU111112367585.
文摘BACKGROUND Antibody-mediated rejection following liver transplantation(LT)has been increasingly recognized,particularly with respect to the emergence of de novo donor-specific antibodies(DSAs)and their impact on graft longevity.While substantial evidence for adult populations exists,research focusing on pediatric LT outcomes remains limited.AIM To investigate the prevalence of human leukocyte antigen(HLA)mismatches and DSA and evaluate their association with rejection episodes after pediatric LT.METHODS A cohort of pediatric LT recipients underwent HLA testing at Santa Casa de Porto Alegre,Brazil,between December 2013 and December 2023.Only patients who survived for>30 days after LT with at least one DSA analysis were included.DSA classes I and II and cross-matches were analyzed.The presence of de novo DSA(dnDSA)was evaluated at least 3 months after LT using the Luminex®single antigen bead method,with a positive reaction threshold set at 1000 MFI.Rejection episodes were confirmed by liver biopsy.RESULTS Overall,67 transplanted children were analyzed;61 received grafts from living donors,85%of whom were related to recipients.Pre-transplant DSA(class I or II)was detected in 28.3%of patients,and dnDSA was detected in 48.4%.The median time to DSA detection after LT was 19.7[interquartile range(IQR):4.3-35.6]months.Biopsyproven rejection occurred in 13 patients at follow-up,with C4d positivity observed in 5/13 Liver biopsies.The median time to rejection was 7.8(IQR:5.7-12.8)months.The presence of dnDSA was significantly associated with rejection(36%vs 3%,P<0.001).The rejection-free survival rates at 12 and 24 months were 76%vs 100%and 58%vs 95%for patients with dnDSA anti-DQ vs those without,respectively.CONCLUSION Our findings highlight the importance of incorporating DSA assessment into pre-and post-transplantation protocols for pediatric LT recipients.Future implications may include immunosuppression minimization strategies based on this analysis in pediatric LT recipients.
基金supported by a grant from the National Natural Science Foundation of China(82170612)Guangzhou Science and Technology Program Key Projects(2023B01J1007)National Natural Science Foundation of China(No.81870597).
文摘Background and Aims:Hepatitis B virus(HBV)infection is a major risk factor for cirrhosis and liver cancer,and its treatment continues to be difficult.We previously demonstrated that a dopamine analog inhibited the packaging of pregenomic RNA into capsids.The present study aimed to determine the effect of dopamine on the expressions of hepatitis B virus surface and e antigens(HBsAg and HBeAg,respectively)and to elucidate the underlying mechanism.Methods:We used dopamine-treated HBVinfected HepG2.2.15 and NTCP-G2 cells to monitor HBsAg and HBeAg expression levels.We analyzed interferon-stimulated gene 15(ISG15)expression in dopamine-treated cells.We knocked down ISG15 and then monitored HBsAg and HBeAg expression levels.We analyzed the expression of Janus kinase(JAK)/signal transducer and activator of transcription(STAT)pathway factors in dopamine-treated cells.We used dopamine hydrochloride-treated adeno-associated virus/HBV-infected mouse model to evaluate HBV DNA,HBsAg,and HBeAg expression.HBV virus was collected from HepAD38.7 cell culture medium.Results:Dopamine inhibited HBsAg and HBeAg expression and upregulated ISG15 expression in HepG2.2.15 and HepG2-NTCP cell lines.ISG15 knockdown increased HBsAg and HBeAg expression in HepG2.2.15 cells.Dopamine-treated cells activated the JAK/STAT pathway,which upregulated ISG15 expression.In the adeno-associated virus-HBV murine infection model,dopamine downregulated HBsAg and HBeAg expression and activated the JAK-STAT/ISG15 axis.Conclusions:Dopamine inhibits the expression of HBsAg and HBeAg by activating the JAK/STAT pathway and upregulating ISG15 expression.
基金the grants from the the National Science Foundation of China,the Key Discipline of Medicine of Jiangsu Province,the Outstanding Medical Academic Leader Program of Jiangsu Province,the Science Foundation of Jiangsu Province,the Key Laboratory Foundation of Suzhou
文摘Background Humoral immunity is an important factor for long-term survival of renal allograft. Here we performed a four-year follow-up to explore the clinical significance of monitoring anti-human leukocyte antigens (HLA) and anti-major histocompatibility complex class I-related chain A (MICA) antibody expression after kidney transplantation. Methods We obtained serial serum samples from 84 kidney transplant patients over a four-year period. All patients were followed up at least 6 months after transplantation and had at least two follow-up points. Anti-HLA and anti-MICA antibody titres and serum creatinine (SCr) levels were evaluated at each follow-up. Patients were divided into 4 groups: HLA(+) MICA(-), HLA(-)MICA(+), HLA(+)MICA(+) and HLA(-)MICA(-). The impact of post-transplant antibody level on kidney allograft function was evaluated. Results Antibodies were detected in 38.1% (32/84) of the renal allograft recipients. HLA, MICA and HLA+MICA expression was observed in 18.89%, 14.44% and 5.93% of the recipients respectively. The most frequent anti-HLA and anti-MICA specific antibodies identified were All, A24, A29, A32, A33, A80; B7, B13, B37; DR17, DR12, DR18, DR52, DR53, DR1, DR4, DR9, DR51; DQ7, DQ4, DQ8, DQ2, DQ9, DQ5, DQ6 and MICA02, MICA18, MICA19, MICA07, MICA27. As the time after transplantation elapsed, more recipients developed de novo antibody expression. Total 11.91% (10/84) of the recipients had de novo antibody expression during the follow up. The average level of SCr and the percentage of recipients with abnormal allograft function were significantly higher in recipients with anti-HLA and/or anti- MICA antibody expression than those without. The appearance of anti-HLA and anti-MICA antibody expression always preceded the increase in SCr value. Conclusions Anti-HLA and anti-MICA antibody expression has predictive value for early and late allograft dysfunction. The presence of donor specific antibody is detrimental to graft function and graft survival.
文摘Neuromyelitis optica(NMO)is an autoimmune demyelinating disorder,predominantly characterized by severe optic neuritis,transverse myelitis and the high level of antibodies against aquaporin-4(AQP4)or NMO-immunoglobulin G(IgG).Researches trying to correlate NMO with specific human leukocyte antigen(HLA)alleles took place in a limited extend in the last few years.Nevertheless,it has become clear that HLAs play a crucial role in the genetic risk of NMO,in the understanding of its pathogenesis and the differential diagnosis mainly from multiple sclerosis(MS),and also from other demyelinating diseases.In this study,we retrieved all the available data in the MEDLINE concerning the distribution of HLA frequencies in NMO and NMO-spectrum diseases,in all available ethnic groups,and compared them with those of MS.The results suggest that,the well-established HLA-DRB1*15:01 allele,associated with MS,plays rather a protective role for NMO.HLA-DRB1*03 allele is highly frequent in the NMO-IgG positive Caucasian patients,while HLA-DPB1*05:01 is the predominant allele in Japanese patients.The HLA-genotype and anti-AQP4 presence are the common immunological components in cases of comorbidity of NMO and other autoimmune diseases.The authors aim to summarize in the critical review the results of these researches worldwide,create a workable table including all this information for an easier reading approach and highlight the importance of these results in therapeutic decision making,using the HLA profile as biomarker in patients’stratification.
基金funded by Vicerrectoría de Investigación—Universidad de Costa Rica,with the Project“C1163 proNGS 2.0:Protocolos operativos estandarizados de análisis de datos moleculares obtenidos por NGS o afines y de algoritmos de inteligencia artificial en modelos biológicos(2021–2023)”.
文摘Tumor-specific antigens or neoantigens are peptides that are expressed only in cancer cells and not in healthy cells.Some of these molecules can induce an immune response,and therefore,their use in immunotherapeutic strategies based on cancer vaccines has been extensively explored.Studies based on these approaches have been triggered by the current high-throughput DNA sequencing technologies.However,there is no universal nor straightforward bioinformatic protocol to discover neoan-tigens using DNA sequencing data.Thus,we propose a bioinformatic protocol to detect tumor-specific antigens associated with single nucleotide variants(SNVs)or“mutations”in tumoral tissues.For this purpose,we used publicly available data to build our model,including exome sequencing data from colorectal cancer and healthy cells obtained from a single case,as well as frequent human leukocyte antigen(HLA)class I alleles in a specific population.HLA data from Costa Rican Central Valley population was selected as an example.The strategy included three main steps:(1)pre-processing of sequencing data;(2)variant calling analysis to detect tumor-specific SNVs in comparison with healthy tissue;and(3)prediction and characterization of peptides(protein fragments,the tumor-specific antigens)derived from the variants,in the context of their affinity with frequent alleles of the selected population.In our model data,we found 28 non-silent SNVs,present in 17 genes in chromosome one.The protocol yielded 23 strong binders peptides derived from the SNVs for frequent HLA class I alleles for the Costa Rican population.Although the analyses were performed as an example to implement the pipeline,to our knowledge,this is the first study of an in silico cancer vaccine using DNA sequencing data in the context of the HLA alleles.It is concluded that the standardized protocol was not only able to identify neoantigens in a specific but also provides a complete pipeline for the eventual design of cancer vaccines using the best bioinformatic practices.
文摘Objective From the ancient period cow’urine has been used as a medicine. In Veda, cow’urine was compared to the nectar. In Susrut, several medicinal properties of cow’ urine have been mentioned and are known to cause weight loss, reversal of certain cardiac and kidney problems, indigestion, stomach ache, edema, etc. However, the literature and scripture did not mention the antigenotoxic properties of cow’urine. Methods In the present investigation, the antigenotoxic/ antioxidant properties of cow’ urine distillate and redistillate were studied in vitro. The antioxidant status and volatile fatty acid levels were determined. Actinomycin-D (0.1ol/L) and hydrogen peroxide (150 mol/L) were used for inducing DNA strand break with 0.1% DMSO as negative control. Dose for the antigenotoxic effect of cow’ urine was chosen from the dose response study carried out earlier. Results Both actinomycin-D and H2O2 caused statistically significant DNA unwinding of 80% & 75% respectively (P<0.001) as revealed by fluorimetric analysis of DNA unwinding (FADU), and the damage could be protected with the redistilled cow urine distillate (1, 50 & 100 ) in simultaneous treatment with genotoxic chemicals. Conclusion The redistillate of cowurine was found to possess total antioxidant status of around 2.6 mmol, contributed mainly by volatile fatty acids (1500 mg/L) as revealed by the GC-MS studies. These fatty acids and other antioxidants might cause the observed protective effects.
基金Instituto de Salud Carlos III,Spanish Ministry of Economy and Competitiveness,No.PI15/01370 and P19/01194and the European Union with the European Fund of Regional Development with the principle of“A manner to build Europe”.
文摘Many mechanisms have been proposed to explain the hypothetical state of hepatic tolerance,which is described by eventual imbalances or deregulation in the balance of cytokines,mediators,effectors,and regulatory cells in the complex milieu of the liver.In this section,we will comment on the importance of donorspecific anti-human leukocyte antigen(HLA)antibodies(DSA)as well as the compatibility and pairings of HLA and killer-cell immunoglobulin-like receptor(KIR)genotypes in the evolution of liver transplantation.Thus,HLA compatibility,viral infections,and HLA-C/KIR combinations have all been linked to liver transplant rejection and survival.There have been reports of increased risk of acute and chronic rejection with ductopenia,faster graft fibrosis,biliary problems,poorer survival,and even de novo autoimmune hepatitis when DSAs are present in the recipient.Higher mean fluorescence intensity(MFI)values of the DSAs and smaller graft size were associated with poorer patient outcomes,implying that high-risk patients with preformed DSAs should be considered for selecting the graft placed and desensitization methods,according to the investigators.Similarly,in a combined kidney-liver transplant,a pretransplant with a visible expression of several DSAs revealed that these antibodies were resistant to treatment.The renal graft was lost owing to antibody-mediated rejection(AMR).The HLA antigens expressed by the transplanted liver graft influenced antibody elimination.Pathologists are increasingly diagnosing AMR in liver transplants,and desensitization therapy has even been employed in situations of AMR,particularly in patients with DSAs in kidney-hepatic transplants and high-class II MFI due to Luminex.In conclusion,after revealing the negative impacts of DSAs with high MFI,pretransplant virtual crossmatch techniques may be appropriate to improve evolution;however,they may extend cold ischemia periods by requiring the donor to be typed.
基金Project supported by the National Natural Science Foundation of China
文摘(2′-5′) oligoadenylate (2-5 A) synthetase is a key enzyme in the establishment of the antiviral and antieetlular states caused by interferon. 2-5 A synthesized by the enzyme is capable of activating a cellular latent endonuclease (RNase L ), leading to the degradation of viral mRNA and cellular rRNA, and inhibiting viral replicatio and cellular proliferation, The level of 2-5 A synthetase in human leukocytes could be enhanced during virus infection or
基金We would like to thank the personnel of the Bergman clinic in Bilthoven, the Netherlands for providing healthy donor skin. We would like to thank Tom O'Toole for the technical assistance with imaging flow cytometry. The present work was funded by KWF (VU2009-2598), the Dutch Science Foundation (NWO, VENI Grant NO 863.10.017), the European Research Council (ERCAdvanced339977), and NanoNext 3D01.
文摘The potential of the skin immune system to generate immune responses is well established, and the skin is actively exploited as a vaccination site. Human skin contains several antigen-presenting cell subsets with specialized functions. In particular, the capacity to cross-present exogenous antigens to CD8^+ T cells is of interest for the design of effective immunotherapies against viruses or cancer. Here, we show that primary human Langerhans cells (LCs) were able to cross-present a synthetic long peptide (SLP) to CD8^+ T cells. In addition, modification of this SLP using antibodies against the receptor langerin, but not dectin-1, further enhanced the cross-presenting capacity of LCs through routing of internalized antigens to less proteolytic early endosome antigen 1 ^+ early endosomes. The potency of LCs to enhance CD8^+ T-cell responses could be further increased through activation of LCs with the toll-like receptor 3 ligand polyinosinic:polycytidylic acid (phC). Altogether, the data provide evidence that human LCs are able to cross-present antigens after langerin-mediated internalization. Furthermore, the potential for antigen modification to target LCs specifically provides a rationale for generating effective anti-tumor or anti-viral cytotoxic T lymphocyte responses.
基金the Natural Science Foundation of Guangdong Province,No.940567the National Natural Science Foundation of China,No.39970374
文摘AIM: To evaluate the level of sperm chromosome aberrations in male patients with hepatitis B, and to directly detect whether there are HBV DNA integrations in sperm chromosomes of hepatitis B patients.METHODS: Sperm chromosomes of 14 tested subjects (5healthy controls, 9 patients with HBV infection, including 1with acute hepatitis B, 2 with chronic active hepatitis B, 4with chronic persistent hepatitis B, 2 chronic HBsAg carriers with no clinical symptoms) were prepared using interspecific in vitro fertilization between zona-free golden hamster ova and human spermatozoa, and the frequencies of aberration spermatozoa were compared between subjects of HBV infection and controls. Fluorescence in situ hybridization (FISH) to sperm chromosome spreads was carried out with biotin-labeled full length HBV DNA probe to detect the specific HBV DNA sequences in the sperm chromosomes.RESULTS: The total frequency of sperm chromosome aberrations in HBV infection group (14.8%, 33/223) was significantly higher than that in the control group (4.3%,5/116). Moreover, the sperm chromosomes in HBV infection patients commonly presented stickiness, clumping, failure to staining, etc, which would affect the analysis of sperm chromosomes. Specific fluorescent signal spots for HBV DNA were seen in sperm chromosomes of one patient with chronic persistent hepatitis. In 9 (9/42) sperm chromosome complements containing fluorescent signal spots, one presented 5 obvious FISH spots, others presented 2 to 4signals. There was significant difference of fluorescence intensity among the signal spots. The distribution of signal sites among chromosomes was random.CONCLUSION: HBV infection can bring about mutagenic effects on sperm chromosomes. Integrations of viral DNA into sperm chromosomes which are multisites and nonspecific, can further increase the instability of sperm chromosomes. This study suggested that HBV infection can create extensively hereditary effects by alteration genetic constituent and/or induction chromosome aberrations, as well as the possibility of vertical transmission of HBV via the germ line to the next generation.