OBJECTIVE: To assess the immune status of auxiliary liver transplantation and to clarify the immune protection of auxiliary liver to other allograft. METHODS: Immunological markers and pathological changes in 3 patien...OBJECTIVE: To assess the immune status of auxiliary liver transplantation and to clarify the immune protection of auxiliary liver to other allograft. METHODS: Immunological markers and pathological changes in 3 patients undergoing auxiliary liver transplantation were analysed. RESULTS: The lower the concentration of immunosuppressive agent, the less the rejection and the milder the intensity in the 3 patients. The function of allograft after auxiliary liver transplantation was excellent. CONCLUSIONS: Patients are in a low immune reaction state after auxiliary liver transplantation. Auxiliary liver can protect other allografts by related immunological mechanisms. The side-effects of low-concentration immunosuppressive agents on auxiliary liver and other allografts are mild.展开更多
The COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)poses a serious threat to human life and health as well as social and economic development.In order to deal with this public h...The COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)poses a serious threat to human life and health as well as social and economic development.In order to deal with this public health event,scientific research institutions around the world have rapidly developed and put vaccines into urgent use,bringing hope to the victory over the epidemic.However,as the Novel Coronavirus continues to spread throughout the world,the virus genome has mutated to form a variety of variants.Among them,the Alpha,Beta,Gamma,Delta and Omicron variants show higher infectivity and higher resistance to vaccines and neutralizing antibodies,posing new challenges to the prevention and treatment of COVID-19.At present,the effect of variants on the effectiveness of developed vaccines has become a hot topic of global discussion.In this paper,we briefly review the new progress of novel Coronavirus variants and their effects on vaccine immune protection.展开更多
In this study, a safety enhanced Salmonella Pullorum (S. Pullorum) ghost was constructed using an antimicrobial peptide gene, and evaluated for its potential as a Pullorum disease (PD) vaccine candidate. The antim...In this study, a safety enhanced Salmonella Pullorum (S. Pullorum) ghost was constructed using an antimicrobial peptide gene, and evaluated for its potential as a Pullorum disease (PD) vaccine candidate. The antimicrobial peptide SMAP29 was co-expressed with lysis gene E to generate S. Pullorum ghosts. No viable bacteria were detectable either in the fermentation culture after induction of gene E- and SMAP29-mediated lysis for 24 h or in the lyophilized ghost products. Specific-pathogen- free (SPF) chicks were intraperitoneally immunized with ghosts at day 7 of age and no mortality, clinical symptoms or signs of PD such as anorexia, depression and diarrhea were observed. On challenge with a virulent S. Pullorum strain at 4 wk post-immunization, a comparatively higher level of protection was observed in the S. Pullorum ghost immunized chickens with a minimum of pathological lesions and bacterial loads compared to the birds in inactivated vaccine groups. In addition, immunization with the S. Pullorum ghosts induced a potent systemic IgG response and was associated with significantly increased levels of cytokine IFN-y and IL-4 and relative percentages of CD4+ and CD8+ T lymphocytes. Our results indicate that SMAP29 can be employed as a new secondary lethal protein to enhance the safety of bacterial ghosts, and to prepare a non-living bacterial vaccine candidate that can prevent PD in chickens.展开更多
Objective: To construct the human B7. 1 (CD80) eukaryocytic expressing vector and its expression on HL60 cells to investigate the immunotherapeutic and immunoprotective effects of B7. 1 molecule on acute leukemia. Met...Objective: To construct the human B7. 1 (CD80) eukaryocytic expressing vector and its expression on HL60 cells to investigate the immunotherapeutic and immunoprotective effects of B7. 1 molecule on acute leukemia. Methods: ①B7. 1 gene was subcloned from the cloning vector using PCR. Both of tlie PCR products and eukaryocytic expressing vector pHook were digested with Apa I , Sal 1 and linked using T4 DNA ligase. Tlie ligased products were transduced into DH5a. B7. 1 gene containing clones were selected by digestion with Apa I and Sal I which were further conformed by sequencing. ②HL60 cells were transformed by B7. 1 with lipofectamine and detected by FACS. ③Tumor formation, mice survival time and the immunotherapeutic and immunoprotective effects by immunization with B7. 1+ cells were evaluated. Results: ①The PCR products were about 620 bp. Six clones were all digested by Apa I and Sal I to produce 620 bp gene fragment which was in tlie same way as 67. 1. It demonstrated t/iat t/ie recombinant vector had been constructed successfully. Further sequencing confirmed the validity of the construction. There was no nucleotide mutation. ② B7. 1 was availably expressed on HL60 cells. ③ B7. 1+ HL60 cells delayed the growth of tumor and prolonged the survival time of leukemic mice, distinctively. So did tlie immunoprotection of B7. 1 + HL60 cells. Conclusion: The human B7. 1(CD80) eukaryocytic expressing vector can be successfully constructed by molecular cloned methods and can be stably and availably expressed on tlie membrane of B7. 1 negative acute myelocytic leukemia (AML) cell line HL60. Furthermore, the costimulatory molecular vaccine has significant effection of immunotherapy and immunoprotection and gives the rationale for clinical application.展开更多
The immune system(IS)is set to provide protection against pathogens,surveillance against tumor cells and promotion of healing.Such functions can be efficiently performed thanks to the presence of a large network of ...The immune system(IS)is set to provide protection against pathogens,surveillance against tumor cells and promotion of healing.Such functions can be efficiently performed thanks to the presence of a large network of cells with variable degrees of specialization.展开更多
Trichosanthin(TCS),extracted from the Chinese medicinal herb Trichosanthes kirilowi,has shown promise for the inhibition of tumor growth.However,its immunomodulatory effect on tumor–host interaction remains unknown.I...Trichosanthin(TCS),extracted from the Chinese medicinal herb Trichosanthes kirilowi,has shown promise for the inhibition of tumor growth.However,its immunomodulatory effect on tumor–host interaction remains unknown.In this study,we focused on the effect of TCS on murine anti-tumor immune response in the 3LL Lewis lung carcinoma tumor model and explored the possible molecular pathways involved.In addition to inhibiting cell proliferation and inducing apoptosis in the 3LL tumor,TCS retarded tumor growth and prolonged mouse survival more significantly in C57BL/6 immunocompetent mice than in nude mice.This reflected the fact that the host immune system was involved in tumor eradication.Using FACS analysis,we found that TCS increased the percentage of effector T cells,particularly Interferon-gamma(IFN-c)producing CD41 and CD81 T cells from tumor-bearing mice.TCS also promoted the vigorous proliferation of antigen-specific effector T cells,markedly increased Th1 cytokine secretion and elicited more memory T cells in tumor-bearing mice,consequently enhancing the anti-tumor response and inducing immune protection.Furthermore,we found that TCS upregulated the expression of tumor suppressor in lung cancer 1(TSLC1)in 3LL tumor cells and the expression of its ligand,class I-restricted T cell-associated molecule(CRTAM),in effector T cells.Blocking TSLC1 expression with small interfering RNA(siRNA)significantly eliminated the effects of TCS on the proliferation and cytokine secretion of effector T cells,suggesting that TCS enhances anti-tumor immune response at least partially by boosting the interaction between TSLC1 and CRTAM.Collectively,our data demonstrate that TCS not only affects tumor cells directly,but also enhances anti-tumor immunity via the interaction between TSLC1 and CRTAM.These findings may lead to the development of a novel approach for tumor regression.展开更多
Human immunodeficiency virus(HIV)-infected individuals exhibit remarkable transcriptomic variation.Transcriptome analyses of antiretroviral therapy(ART)-free chronically infected HIV-1 patients with different clinical...Human immunodeficiency virus(HIV)-infected individuals exhibit remarkable transcriptomic variation.Transcriptome analyses of antiretroviral therapy(ART)-free chronically infected HIV-1 patients with different clinical outcomes are likely to aid the development of vaccine and immune therapies.Here,we performed microarray analyses on whole-blood derived RNA from 89 ART-free HIV-1-infected individuals from 2 cohorts.The differentially expressed genes were analyzed between long-term non-progressors,viremic non-progressors and typical progressors,and between elite controllers and non-elite controllers among the long-term nonprogressors.Several genes related to T-cell growth,proliferation and differentiation and antiapoptosis were upregulated,whereas interferon-stimulated genes and inflammatory genes were significantly downregulated in long-term non-progressors and viremic non-progressors.The observations above were further confirmed in the set of 261 genes that correlated with disease progression during a 5-year follow-up,which included 51 genes significantly associated with slower disease progression,and 210 genes associated with aggressive disease progression.Overall,our data suggest that it is vital to maintain the homeostasis of the immune system when mounting antiviral immune responses.Immune therapeutics able to reconstruct immune homeostasis are likely to be required for immune reconstitution in the context of ART,such as the administration of interleukin-7,healthy allogenic CD4^(+)T cells(providing CD4^(+)T-cell growth factors),or Tregs.展开更多
Background The vaccination of mice with DNA encoding single candidate antigens has failed to induce significant protection against Schistosoma japonicum (S. japonicum) challenge infections In this study, we evaluated ...Background The vaccination of mice with DNA encoding single candidate antigens has failed to induce significant protection against Schistosoma japonicum (S. japonicum) challenge infections In this study, we evaluated the feasibility of using a multivalent DNA vaccine which co expressed S japonicum integral membrane protein Sj23 and murine cytokine IL 12 to induce protective immune responses Methods The plasmid pVIVO2 IL12 Sj23, a eukaryotic expression vector expressing Sj23 and murine IL 12 simultaneously, was constructed, identified, and tested for expression in vitro Its ability to protect against S japonicum challenge infections was analyed according to worm reduction rate and egg reduction rate after vaccination of BALB/c mice The serum levels of specific IgG antibody were determined by enzyme linked immuno sorbent assay (ELISA) and Western blot analysis Using cultured spleen cells, IFN γ and IL 4 post stimulation were quantified by ELISA The phenotypes of splenocyte populations were analyzed by flow cytometry (FCM) Results The plasmid DNA pVIVO2 IL12 Sj23 was proven to express well in vitro by transient transfection of HEK 293 cells Immunization resulted in a worm reduction rate of 45 53% and egg reduction rate of 58 35% ELISA and Western blot analysis indicated that immunized mice generated specific IgG against Sj23 Spleen cells showed significant increases in IFN γ but decreases in IL 4 No significant differences in CD4 + and CD8 + subgroup ratios were observed after the challenges Conclusions The multivalent DNA vaccine pVIVO2 IL12 Sj23 is sufficient to elicit moderate but highly significant levels of protective immunity against challenge infections Cytokine IL 12, as a gene adjuvant, was able to enhance the Th1 responses and, hence, the protective immunity展开更多
Human respiratory syncytial virus(RSV)infection is the leading cause of lower respiratory tract illness(LRTI),and no vaccine against LRTI has proven to be safe and effective in infants.Our study assessed attenuated re...Human respiratory syncytial virus(RSV)infection is the leading cause of lower respiratory tract illness(LRTI),and no vaccine against LRTI has proven to be safe and effective in infants.Our study assessed attenuated recombinant RSVs as vaccine candidates to prevent RSV infection in mice.The constructed recombinant plasmids harbored(5′to 3′)a T7 promoter,hammerhead ribozyme,RSV Long strain antigenomic cDNA with cold-passaged(cp)mutations or cp combined with temperature-sensitive attenuated mutations from the A2 strain(A2cpts)or further combined with SH gene deletion(A2cptsΔSH),HDV ribozyme(δ),and a T7 terminator.These vectors were subsequently co-transfected with four helper plasmids encoding N,P,L,and M2-1 viral proteins into BHK/T7-9 cells,and the recovered viruses were then passaged in Vero cells.The rescued recombinant RSVs(rRSVs)were named rRSV-Long/A2cp,rRSV-Long/A2cpts,and rRSV-Long/A2cptsΔSH,respectively,and stably passaged in vitro,without reversion to wild type(wt)at sites containing introduced mutations or deletion.Although rRSV-Long/A2cpts and rRSV-Long/A2cptsΔSH displayed temperature-sensitive(ts)phenotype in vitro and in vivo,all rRSVs were significantly attenuated in vivo.Furthermore,BALB/c mice immunized with rRSVs produced Th1-biased immune response,resisted wtRSV infection,and were free from enhanced respiratory disease.We showed that the combination ofΔSH with attenuation(att)mutations of cpts contributed to improving att phenotype,efficacy,and gene stability of rRSV.By successfully introducing att mutations and SH gene deletion into the RSV Long parent and producing three rRSV strains,we have laid an important foundation for the development of RSV live attenuated vaccines.展开更多
OBJECTIVE:This study investigated the immunoregulatory and protective roles of Yinchenhao decoction,a compound of Chinese herbal medicine,in a mouse model of concanavalin A(Con A)-induced chronic liver injury.METH...OBJECTIVE:This study investigated the immunoregulatory and protective roles of Yinchenhao decoction,a compound of Chinese herbal medicine,in a mouse model of concanavalin A(Con A)-induced chronic liver injury.METHODS:Female Bal B/c mice were randomly divided into 4 groups:normal control,Con A model,Con A model treated with Yinchenhao decoction(400 mg/kg,orally),and Con A model treated with dexamethasone(0.5 mg/kg,orally).All treatments were given once a day for 28 d.Except of the normal control,mice received tail vein injection of Con A(10 mg/kg)on days 7,14,21,and 28,at 1 h after treatment with Yinchenhao decoction or dexamethasone or saline to induce chronic liver injury.RESULTS:Repeated Con A injection induced chronic liver injury,which was evidenced by infl ammatory cell infi ltration and necrosis,increased serum alanine aminotranferease activities,decreased albumin levels,and an imbalanced expression of immunoregulatory genes in the liver tissues including signifi cantly enhanced interferon-γ,interleukin-4,monocyte chemotactic protein-1,and cluster of differentiation 163 m RNA levels,and reduced tumor necrosis factor-αand interleukin-6 m RNA levels.Treatment with Yinchenhao decoction signifi cantly reversed the Con A-induced changes in immunoregulatory gene expression in the liver tissues,reduced serum alanine aminotranferease activity,enhanced serum albumin level,and attenuated the extent of liver infl ammation and necrosis.Furthermore,Yinchenhao decoction did not result in hepatocyte degeneration and spleen weight loss that were observed in mice received long-term treatment with dexamethasone.CONCLUSION:Yinchenhao decoction treatment protected liver against the Con A-induced chronic liver damage and improved liver function,which were associated with the modulation of gene expression related to immune/infl ammatory response.展开更多
Maintenance of homeostasis and immune protection rely on the coordinated action of different physiological systems.Bidirectional communication between the immune system and physiological systems is required to sense a...Maintenance of homeostasis and immune protection rely on the coordinated action of different physiological systems.Bidirectional communication between the immune system and physiological systems is required to sense and restore any disruption of equilibrium.Recent transcriptomic analyses of innate lymphoid cells(ILCs)from different tissues have revealed that ILCs express a large array of receptors involved in the recognition of neuropeptides,hormones and metabolic signals.ILCs rapidly secrete effector cytokines that are central in the development and activation of early immune responses,but they also constitutively secrete mediators that are important for tissue homeostasis.To achieve these functions effectively,ILCs integrate intrinsic and extrinsic signals that modulate their constitutive and induced activity.Disruption of the regulation of ILCs by physiological regulators leads to altered immune responses with harmful consequences for the organism.An understanding of these complex interactions between the immune system and physiological mediators is crucial to decipher the events leading to the protective versus pathological effects of these cells.展开更多
Background and Aims:Hepatitis B vaccine is the most effective preventive measure against hepatitis B virus(HBV)infection.However,the risk of HBV breakthrough infection in fully immunized children(neonatal hepatitis B ...Background and Aims:Hepatitis B vaccine is the most effective preventive measure against hepatitis B virus(HBV)infection.However,the risk of HBV breakthrough infection in fully immunized children(neonatal hepatitis B immunization)who receive immunosuppressive therapy and transfusion of blood components is not well characterized.In this real-world study,we aimed to investigate the immune protection conferred by neonatal hepatitis B vaccine in children with acute lymphoblastic leukemia(ALL)who were treated with immunosuppressive therapy and blood component transfusions.Methods:Children with ALL who had received all three doses of neonatal hepatitis B vaccine were included in this study.HBV seromarkers were detected before and after the initiation of immunosuppressive therapy.Results:A total of 1,011 children with ALL who were fully vaccinated against hepatitis B in infancy before the initiation of immunosuppressive therapy were eligible for inclusion.HBV infection was detected in four of 410 children(0.98%)with an HBsAg test after the initiation of immunosuppressive therapy.The median interval from treatment initiation was 19 months.Conclusions:Three doses of neonatal hepatitis B vaccine conferred adequate protection.In endemic regions,there is a low risk of HBV breakthrough infection in fully immunized children with immunosuppressive therapy.展开更多
The lack of an effective preventative vaccine against tuberculosis(TB)presents a great challenge to TB control.Since it takes an extremely long time to accurately determine the protective efficacy of TB vaccines,there...The lack of an effective preventative vaccine against tuberculosis(TB)presents a great challenge to TB control.Since it takes an extremely long time to accurately determine the protective efficacy of TB vaccines,there is a great need to identify the surrogate signatures of protection to facilitate vaccine development.Unfortunately,antigen-specific Th1 cytokines that are currently used to evaluate the protective efficacy of the TB vaccine,do not align with the protection and failure of TB vaccine candidates in clinical trials.In this review,we discuss the limitation of current Th1 cytokines as surrogates of protection and address the potential elements that should be considered to finalize the true functional signatures of protective immunity against TB.展开更多
Objective To study protective immunity afforded by murine immunization with DNA vaccine of Schistosoma japonicum (S. japonicum) as measured by reduction in worm burden and host antibody, cytokines.Methods DNA vaccin...Objective To study protective immunity afforded by murine immunization with DNA vaccine of Schistosoma japonicum (S. japonicum) as measured by reduction in worm burden and host antibody, cytokines.Methods DNA vaccine pCD Sj32 was constructed. identificated and expressed. pCD Sj32 could induce substantial protective immunity against infection of S. japonicum in BALB/c mice. The best efficacy can be produced with one injection of 100?μg DNA into the quadriceps muscle, combined with challenge for 8 weeks after immunization. T lymphocyte subsets of CD 8 +, IL 2. TNF and IFN γ of experimental animal could play important roles in regulating immune functions of schistosomiasis. Results High titre of specific antibody IgG could be induced by vaccinated with pCD Sj32, and antibody can mediate macrophage to produce ADCC effects in vitro. Conclusion pCD Sj32 may represent a new approach to developing subunit vaccine.展开更多
The morphological switch between yeast and hyphae of Candida albicans is essential for its interaction with the host defense system.However,the lack of understanding of host-pathogen interactions during C.albicans inf...The morphological switch between yeast and hyphae of Candida albicans is essential for its interaction with the host defense system.However,the lack of understanding of host-pathogen interactions during C.albicans infection greatly hampers the development of effective immunotherapies.Here,we found that priming with the C.albicans FLO8-deficient(flo8)mutant,locked in yeast form,protected mice from subsequent lethal C.albicans infection.Deficiency of Dectin-2,a fungus-derivedα-mannan recognition receptor,completely blocked flo8 mutant-induced protection.Mechanistically,the flo8 mutant-induced Dectin-2/CARD9-mediated IL-10 production in DCs and macrophages to block thymus atrophy by inhibiting the C.albicans-induced apoptosis of thymic T cells,which facilitated the continuous output of naive T cells from the thymus to the spleen.Continuous recruitment of naive T cells to the spleen enhanced Th1-biased antifungal immune responses.Consequently,depletion of CD4^(+)T cells or blockade of IL-10 receptor function using specific antibodies in mice completely blocked the protective effects of flo8 mutant priming against C.albicans infection.Moreover,mannans exposed on the surface of the flo8 mutant were responsible for eliciting protective immunity by inhibiting the C.albicans-induced apoptosis of thymic T cells to sustain the number of naive T cells in the spleen.Importantly,priming with the flo8 mutant extensively protected mice from polymicrobial infection caused by cecal ligation and puncture(CLP)by enhancing Th1-biased immune responses.Together,our findings imply that targeting FLO8 in C.albicans elicits protective immune responses against polymicrobial infections and that mannans extracted from the flo8 mutant are potential immunotherapeutic candidate(s)for controlling infectious diseases.展开更多
Interplay between macrophages and dendritic cells in the processing and presentation of bacterial antigens for T-cell immune responses remains poorly understood. Using a Listeria monocytogenes (Lm) infection model, ...Interplay between macrophages and dendritic cells in the processing and presentation of bacterial antigens for T-cell immune responses remains poorly understood. Using a Listeria monocytogenes (Lm) infection model, we demonstrate that dendritic cells (DCs) require the support of macrophages to elicit protective immunity against Lm infection. DCs themselves were inefficient at taking up Lm but capable of taking up microparticles (MPs) released by Lm-infected macrophages. These MPs transferred Lm antigens to DCs, allowing DCs to present Lm antigen to effector T cells. MP-mediated Lm antigen transfer required M HC class I participation, since M HC class I deficiency in macrophages resulted in a significant reduction of T-cell activation. Moreover, the vaccination of mice with MPs from Lm-infected macrophages produced strong protective immunity against Lm infection. We here identify an intrinsic antigen transfer program between macrophages and DCs during Lm infection, and emphasize that macrophages also play an essential role in DC-elicited Lm-specific T-cell responses.展开更多
Flaviviruses comprise approximately 70 closely related RNA viruses. These include several mosquito-borne pathogens, such as yellow fever virus (YFV), dengue virus (DENV), and Japanese encephalitis virus (JEV), w...Flaviviruses comprise approximately 70 closely related RNA viruses. These include several mosquito-borne pathogens, such as yellow fever virus (YFV), dengue virus (DENV), and Japanese encephalitis virus (JEV), which can cause significant human diseases and thus are of great medical importance. Vaccines against both YFV and JEV have been used successfully in humans for decades; however, the development of a DENV vaccine has encountered considerable obstacles. Here, we review the protective immune responses elicited by the vaccine against YFV to provide some insights into the development of a protective DENV vaccine.展开更多
Generation and maintenance of antigen-specific effector and memory T cells are central events in immune responses against infections.We show that TNF receptor-associated factor 2(TRAF2)maintains a survival signaling a...Generation and maintenance of antigen-specific effector and memory T cells are central events in immune responses against infections.We show that TNF receptor-associated factor 2(TRAF2)maintains a survival signaling axis in effector and memory CD8 T cells required for immune responses against infections.This signaling axis involves activation of Tpl2 and its downstream kinase ERK by NF-κB-inducing kinase(NIK)and degradation of the proapoptotic factor Bim.NIK mediates Tpl2 activation by stimulating the phosphorylation and degradation of the Tpl2 inhibitor p105.Interestingly,while NIK is required for Tpl2-ERK signaling under normal conditions,uncontrolled NIK activation due to loss of its negative regulator,TRAF2,causes constitutive degradation of p105 and Tpl2,leading to severe defects in ERK activation and effector/memory CD8 T cell survival.Thus,TRAF2 controls a previously unappreciated signaling axis mediating effector/memory CD8 T cell survival and protective immunity.展开更多
Background Recently congenital infection with Schistosoma japonicum (S. japonicum) has been domonstrated in pigs, rabbits, mice and dogs. We explored the rabbit as an animal model for the congenital infection of schi...Background Recently congenital infection with Schistosoma japonicum (S. japonicum) has been domonstrated in pigs, rabbits, mice and dogs. We explored the rabbit as an animal model for the congenital infection of schistosomiasis japonica and assessed the effect of a congenital S. japonicum infection on the resistance of rabbit kittens to a postnatal challenge infection.Methods Sixteen pregnant New Zealand white rabbits were infected with a single dose of S. japonicum cercariae. The exposed animals were divided into three groups according to the gestation age at the time of infection. Diagnosis of prenatally acquired S. japonicum infection in the rabbit kittens was primarily based on serological tests in combination with parasitological and histopathological findings. Congenitally infected kittens were challenged percutaneously with 100 S. japonicum cercariae to assess the effect of a congenital S. japonicum infection on kitten resistance to a postnatal challenge infection.Results The overall prevalence of congenital infection in offspring of infected mothers was 20% (12/60). The congenital infection rate in group L (late gestation) was much higher than in group E (early gestation) and group M (mid-gestation) (P<0.05). After a postnatal challenge infection, prenatally infected kittens had a 54.66% worm reduction rate, 41.45% egg reduction rate, and 51.76% granuloma size reduction rate compared to nave kittens.Conclusions This study demonstrates the possibility of congenital infection of S. japonicum in rabbits and the resistance of congenitally infected kittens to a postnatal challenge infection. These results have important implications not only for epidemiological investigations, but also in designing government control programs for schistosomiasis.展开更多
Ems is a highly glycosylated envelope protein of classical swine fever virus (CSFV) with RNase ac- tivity. Ems can induce neutralizing antibodies and provide immune protection against CSFV infection. In this study, ...Ems is a highly glycosylated envelope protein of classical swine fever virus (CSFV) with RNase ac- tivity. Ems can induce neutralizing antibodies and provide immune protection against CSFV infection. In this study, the RNase domain of the Ems was produced in Eschenchia coil. Its reactivity with CSFV-positive sera and its ability to induce antibodies and to provide protective immunity were then investigated. The serological tests showed that the prokaryotically expressed RNase domain of the Ems retained its antigenicity and in- duced high titers of humoral responses. However, only partial protection and a limited amount of neutralizing antibodies were demonstrated by an in vitro neutralization test and an immunization/challenge test. The re- sults suggest that other essential factors rather than simply enhancing the immunogenicity of Ems should be taken into consideration when Er"s is enrolled as one of the components of a candidate vaccine.展开更多
文摘OBJECTIVE: To assess the immune status of auxiliary liver transplantation and to clarify the immune protection of auxiliary liver to other allograft. METHODS: Immunological markers and pathological changes in 3 patients undergoing auxiliary liver transplantation were analysed. RESULTS: The lower the concentration of immunosuppressive agent, the less the rejection and the milder the intensity in the 3 patients. The function of allograft after auxiliary liver transplantation was excellent. CONCLUSIONS: Patients are in a low immune reaction state after auxiliary liver transplantation. Auxiliary liver can protect other allografts by related immunological mechanisms. The side-effects of low-concentration immunosuppressive agents on auxiliary liver and other allografts are mild.
基金General Project of Huoshenshan Hospital Scientific Research Fund(No.HSS 217)Intra hospital COVID 19 Fund Project of Hospital No.940(No.20yjky020)。
文摘The COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)poses a serious threat to human life and health as well as social and economic development.In order to deal with this public health event,scientific research institutions around the world have rapidly developed and put vaccines into urgent use,bringing hope to the victory over the epidemic.However,as the Novel Coronavirus continues to spread throughout the world,the virus genome has mutated to form a variety of variants.Among them,the Alpha,Beta,Gamma,Delta and Omicron variants show higher infectivity and higher resistance to vaccines and neutralizing antibodies,posing new challenges to the prevention and treatment of COVID-19.At present,the effect of variants on the effectiveness of developed vaccines has become a hot topic of global discussion.In this paper,we briefly review the new progress of novel Coronavirus variants and their effects on vaccine immune protection.
基金supported by grants from the National Key Research and Development Program of China (2016YFD0501608)the National Natural Science Foundation of China (31470893)+1 种基金the Special Fund for Agro-scientific Research in the Public Interest,China (201403054)the National High Technology Research and Development Program of China (2011AA10A210)
文摘In this study, a safety enhanced Salmonella Pullorum (S. Pullorum) ghost was constructed using an antimicrobial peptide gene, and evaluated for its potential as a Pullorum disease (PD) vaccine candidate. The antimicrobial peptide SMAP29 was co-expressed with lysis gene E to generate S. Pullorum ghosts. No viable bacteria were detectable either in the fermentation culture after induction of gene E- and SMAP29-mediated lysis for 24 h or in the lyophilized ghost products. Specific-pathogen- free (SPF) chicks were intraperitoneally immunized with ghosts at day 7 of age and no mortality, clinical symptoms or signs of PD such as anorexia, depression and diarrhea were observed. On challenge with a virulent S. Pullorum strain at 4 wk post-immunization, a comparatively higher level of protection was observed in the S. Pullorum ghost immunized chickens with a minimum of pathological lesions and bacterial loads compared to the birds in inactivated vaccine groups. In addition, immunization with the S. Pullorum ghosts induced a potent systemic IgG response and was associated with significantly increased levels of cytokine IFN-y and IL-4 and relative percentages of CD4+ and CD8+ T lymphocytes. Our results indicate that SMAP29 can be employed as a new secondary lethal protein to enhance the safety of bacterial ghosts, and to prepare a non-living bacterial vaccine candidate that can prevent PD in chickens.
基金Supported by Grant from the Key Clinical Department Development Item of China,Health Ministry(20012131)
文摘Objective: To construct the human B7. 1 (CD80) eukaryocytic expressing vector and its expression on HL60 cells to investigate the immunotherapeutic and immunoprotective effects of B7. 1 molecule on acute leukemia. Methods: ①B7. 1 gene was subcloned from the cloning vector using PCR. Both of tlie PCR products and eukaryocytic expressing vector pHook were digested with Apa I , Sal 1 and linked using T4 DNA ligase. Tlie ligased products were transduced into DH5a. B7. 1 gene containing clones were selected by digestion with Apa I and Sal I which were further conformed by sequencing. ②HL60 cells were transformed by B7. 1 with lipofectamine and detected by FACS. ③Tumor formation, mice survival time and the immunotherapeutic and immunoprotective effects by immunization with B7. 1+ cells were evaluated. Results: ①The PCR products were about 620 bp. Six clones were all digested by Apa I and Sal I to produce 620 bp gene fragment which was in tlie same way as 67. 1. It demonstrated t/iat t/ie recombinant vector had been constructed successfully. Further sequencing confirmed the validity of the construction. There was no nucleotide mutation. ② B7. 1 was availably expressed on HL60 cells. ③ B7. 1+ HL60 cells delayed the growth of tumor and prolonged the survival time of leukemic mice, distinctively. So did tlie immunoprotection of B7. 1 + HL60 cells. Conclusion: The human B7. 1(CD80) eukaryocytic expressing vector can be successfully constructed by molecular cloned methods and can be stably and availably expressed on tlie membrane of B7. 1 negative acute myelocytic leukemia (AML) cell line HL60. Furthermore, the costimulatory molecular vaccine has significant effection of immunotherapy and immunoprotection and gives the rationale for clinical application.
文摘The immune system(IS)is set to provide protection against pathogens,surveillance against tumor cells and promotion of healing.Such functions can be efficiently performed thanks to the presence of a large network of cells with variable degrees of specialization.
基金the National Key Technologies R&D Program of China during the Eleventh Five-Year Plan Period(2009ZX10004-104 and 2009ZX09301-011)National Science Foundation of China(30872378 and 81072408)the Science and Technology Commission of Shanghai Municipality(10JC1401100)in China and National 973 Project(2010CB912603 and 2011CB910400)in China.We thank the editors of Editage Company for professional editing of the article.
文摘Trichosanthin(TCS),extracted from the Chinese medicinal herb Trichosanthes kirilowi,has shown promise for the inhibition of tumor growth.However,its immunomodulatory effect on tumor–host interaction remains unknown.In this study,we focused on the effect of TCS on murine anti-tumor immune response in the 3LL Lewis lung carcinoma tumor model and explored the possible molecular pathways involved.In addition to inhibiting cell proliferation and inducing apoptosis in the 3LL tumor,TCS retarded tumor growth and prolonged mouse survival more significantly in C57BL/6 immunocompetent mice than in nude mice.This reflected the fact that the host immune system was involved in tumor eradication.Using FACS analysis,we found that TCS increased the percentage of effector T cells,particularly Interferon-gamma(IFN-c)producing CD41 and CD81 T cells from tumor-bearing mice.TCS also promoted the vigorous proliferation of antigen-specific effector T cells,markedly increased Th1 cytokine secretion and elicited more memory T cells in tumor-bearing mice,consequently enhancing the anti-tumor response and inducing immune protection.Furthermore,we found that TCS upregulated the expression of tumor suppressor in lung cancer 1(TSLC1)in 3LL tumor cells and the expression of its ligand,class I-restricted T cell-associated molecule(CRTAM),in effector T cells.Blocking TSLC1 expression with small interfering RNA(siRNA)significantly eliminated the effects of TCS on the proliferation and cytokine secretion of effector T cells,suggesting that TCS enhances anti-tumor immune response at least partially by boosting the interaction between TSLC1 and CRTAM.Collectively,our data demonstrate that TCS not only affects tumor cells directly,but also enhances anti-tumor immunity via the interaction between TSLC1 and CRTAM.These findings may lead to the development of a novel approach for tumor regression.
基金This work was supported by the National Grand Program on Key Infectious Disease Control(No.2017ZX10202102)the National Nature Science Foundation of China(No.81561128008).
文摘Human immunodeficiency virus(HIV)-infected individuals exhibit remarkable transcriptomic variation.Transcriptome analyses of antiretroviral therapy(ART)-free chronically infected HIV-1 patients with different clinical outcomes are likely to aid the development of vaccine and immune therapies.Here,we performed microarray analyses on whole-blood derived RNA from 89 ART-free HIV-1-infected individuals from 2 cohorts.The differentially expressed genes were analyzed between long-term non-progressors,viremic non-progressors and typical progressors,and between elite controllers and non-elite controllers among the long-term nonprogressors.Several genes related to T-cell growth,proliferation and differentiation and antiapoptosis were upregulated,whereas interferon-stimulated genes and inflammatory genes were significantly downregulated in long-term non-progressors and viremic non-progressors.The observations above were further confirmed in the set of 261 genes that correlated with disease progression during a 5-year follow-up,which included 51 genes significantly associated with slower disease progression,and 210 genes associated with aggressive disease progression.Overall,our data suggest that it is vital to maintain the homeostasis of the immune system when mounting antiviral immune responses.Immune therapeutics able to reconstruct immune homeostasis are likely to be required for immune reconstitution in the context of ART,such as the administration of interleukin-7,healthy allogenic CD4^(+)T cells(providing CD4^(+)T-cell growth factors),or Tregs.
文摘Background The vaccination of mice with DNA encoding single candidate antigens has failed to induce significant protection against Schistosoma japonicum (S. japonicum) challenge infections In this study, we evaluated the feasibility of using a multivalent DNA vaccine which co expressed S japonicum integral membrane protein Sj23 and murine cytokine IL 12 to induce protective immune responses Methods The plasmid pVIVO2 IL12 Sj23, a eukaryotic expression vector expressing Sj23 and murine IL 12 simultaneously, was constructed, identified, and tested for expression in vitro Its ability to protect against S japonicum challenge infections was analyed according to worm reduction rate and egg reduction rate after vaccination of BALB/c mice The serum levels of specific IgG antibody were determined by enzyme linked immuno sorbent assay (ELISA) and Western blot analysis Using cultured spleen cells, IFN γ and IL 4 post stimulation were quantified by ELISA The phenotypes of splenocyte populations were analyzed by flow cytometry (FCM) Results The plasmid DNA pVIVO2 IL12 Sj23 was proven to express well in vitro by transient transfection of HEK 293 cells Immunization resulted in a worm reduction rate of 45 53% and egg reduction rate of 58 35% ELISA and Western blot analysis indicated that immunized mice generated specific IgG against Sj23 Spleen cells showed significant increases in IFN γ but decreases in IL 4 No significant differences in CD4 + and CD8 + subgroup ratios were observed after the challenges Conclusions The multivalent DNA vaccine pVIVO2 IL12 Sj23 is sufficient to elicit moderate but highly significant levels of protective immunity against challenge infections Cytokine IL 12, as a gene adjuvant, was able to enhance the Th1 responses and, hence, the protective immunity
基金This work was supported by grants from the Natural Science Foundation of China(81771777,32070922).
文摘Human respiratory syncytial virus(RSV)infection is the leading cause of lower respiratory tract illness(LRTI),and no vaccine against LRTI has proven to be safe and effective in infants.Our study assessed attenuated recombinant RSVs as vaccine candidates to prevent RSV infection in mice.The constructed recombinant plasmids harbored(5′to 3′)a T7 promoter,hammerhead ribozyme,RSV Long strain antigenomic cDNA with cold-passaged(cp)mutations or cp combined with temperature-sensitive attenuated mutations from the A2 strain(A2cpts)or further combined with SH gene deletion(A2cptsΔSH),HDV ribozyme(δ),and a T7 terminator.These vectors were subsequently co-transfected with four helper plasmids encoding N,P,L,and M2-1 viral proteins into BHK/T7-9 cells,and the recovered viruses were then passaged in Vero cells.The rescued recombinant RSVs(rRSVs)were named rRSV-Long/A2cp,rRSV-Long/A2cpts,and rRSV-Long/A2cptsΔSH,respectively,and stably passaged in vitro,without reversion to wild type(wt)at sites containing introduced mutations or deletion.Although rRSV-Long/A2cpts and rRSV-Long/A2cptsΔSH displayed temperature-sensitive(ts)phenotype in vitro and in vivo,all rRSVs were significantly attenuated in vivo.Furthermore,BALB/c mice immunized with rRSVs produced Th1-biased immune response,resisted wtRSV infection,and were free from enhanced respiratory disease.We showed that the combination ofΔSH with attenuation(att)mutations of cpts contributed to improving att phenotype,efficacy,and gene stability of rRSV.By successfully introducing att mutations and SH gene deletion into the RSV Long parent and producing three rRSV strains,we have laid an important foundation for the development of RSV live attenuated vaccines.
基金This work was supported by the National Natural Science Foundation of China (No. 90409020);the College Young Teacher Training Program of Shanghai Municipal Education Commission (No. ZZszy13022).
文摘OBJECTIVE:This study investigated the immunoregulatory and protective roles of Yinchenhao decoction,a compound of Chinese herbal medicine,in a mouse model of concanavalin A(Con A)-induced chronic liver injury.METHODS:Female Bal B/c mice were randomly divided into 4 groups:normal control,Con A model,Con A model treated with Yinchenhao decoction(400 mg/kg,orally),and Con A model treated with dexamethasone(0.5 mg/kg,orally).All treatments were given once a day for 28 d.Except of the normal control,mice received tail vein injection of Con A(10 mg/kg)on days 7,14,21,and 28,at 1 h after treatment with Yinchenhao decoction or dexamethasone or saline to induce chronic liver injury.RESULTS:Repeated Con A injection induced chronic liver injury,which was evidenced by infl ammatory cell infi ltration and necrosis,increased serum alanine aminotranferease activities,decreased albumin levels,and an imbalanced expression of immunoregulatory genes in the liver tissues including signifi cantly enhanced interferon-γ,interleukin-4,monocyte chemotactic protein-1,and cluster of differentiation 163 m RNA levels,and reduced tumor necrosis factor-αand interleukin-6 m RNA levels.Treatment with Yinchenhao decoction signifi cantly reversed the Con A-induced changes in immunoregulatory gene expression in the liver tissues,reduced serum alanine aminotranferease activity,enhanced serum albumin level,and attenuated the extent of liver infl ammation and necrosis.Furthermore,Yinchenhao decoction did not result in hepatocyte degeneration and spleen weight loss that were observed in mice received long-term treatment with dexamethasone.CONCLUSION:Yinchenhao decoction treatment protected liver against the Con A-induced chronic liver damage and improved liver function,which were associated with the modulation of gene expression related to immune/infl ammatory response.
基金supported by grants and fellowships from the National Health and Medical Research Council(NHMRC)of Australia(APP1165443)the Australian Research Career Development Fellowship(APP1123000)。
文摘Maintenance of homeostasis and immune protection rely on the coordinated action of different physiological systems.Bidirectional communication between the immune system and physiological systems is required to sense and restore any disruption of equilibrium.Recent transcriptomic analyses of innate lymphoid cells(ILCs)from different tissues have revealed that ILCs express a large array of receptors involved in the recognition of neuropeptides,hormones and metabolic signals.ILCs rapidly secrete effector cytokines that are central in the development and activation of early immune responses,but they also constitutively secrete mediators that are important for tissue homeostasis.To achieve these functions effectively,ILCs integrate intrinsic and extrinsic signals that modulate their constitutive and induced activity.Disruption of the regulation of ILCs by physiological regulators leads to altered immune responses with harmful consequences for the organism.An understanding of these complex interactions between the immune system and physiological mediators is crucial to decipher the events leading to the protective versus pathological effects of these cells.
基金supported by the National Natural Science Foundation of China(No.81371876)National Clinical Re-search Center for Child Health and Disorders General Pro-ject(No.NCRCCHD-2019-GP-04)+2 种基金National Clinical Research Center for Child Health and Disorders Youth Project(No.NCRCCHD-2021-YP-03)Outstanding Youth Foundation of Children’s Hospital of Chongqing Medical UniversityCentral Government Guides Local Science,Technology Develop-ment Projects-demonstration of Science and Technology In-novation projects.
文摘Background and Aims:Hepatitis B vaccine is the most effective preventive measure against hepatitis B virus(HBV)infection.However,the risk of HBV breakthrough infection in fully immunized children(neonatal hepatitis B immunization)who receive immunosuppressive therapy and transfusion of blood components is not well characterized.In this real-world study,we aimed to investigate the immune protection conferred by neonatal hepatitis B vaccine in children with acute lymphoblastic leukemia(ALL)who were treated with immunosuppressive therapy and blood component transfusions.Methods:Children with ALL who had received all three doses of neonatal hepatitis B vaccine were included in this study.HBV seromarkers were detected before and after the initiation of immunosuppressive therapy.Results:A total of 1,011 children with ALL who were fully vaccinated against hepatitis B in infancy before the initiation of immunosuppressive therapy were eligible for inclusion.HBV infection was detected in four of 410 children(0.98%)with an HBsAg test after the initiation of immunosuppressive therapy.The median interval from treatment initiation was 19 months.Conclusions:Three doses of neonatal hepatitis B vaccine conferred adequate protection.In endemic regions,there is a low risk of HBV breakthrough infection in fully immunized children with immunosuppressive therapy.
基金This study was supported by Thirteenth-Fifth Mega-Scientific Projects(2017ZX10103004)National Natural Science Foundation of China(81501714,81525016,81471913)+3 种基金National Key R&D Program of China(2016YFE0106900)Natural Science Foundation of Guangdong(2014A030313789)Shenzhen Scientific and Technological Project(JCYJ20170307095003051,JCYJ20170412151620658 and JSGG20140701164558078)and Sanming Project of Medicine in Shenzhen(GCZX2015043015340574,ZDSYS201504301534057).
文摘The lack of an effective preventative vaccine against tuberculosis(TB)presents a great challenge to TB control.Since it takes an extremely long time to accurately determine the protective efficacy of TB vaccines,there is a great need to identify the surrogate signatures of protection to facilitate vaccine development.Unfortunately,antigen-specific Th1 cytokines that are currently used to evaluate the protective efficacy of the TB vaccine,do not align with the protection and failure of TB vaccine candidates in clinical trials.In this review,we discuss the limitation of current Th1 cytokines as surrogates of protection and address the potential elements that should be considered to finalize the true functional signatures of protective immunity against TB.
文摘Objective To study protective immunity afforded by murine immunization with DNA vaccine of Schistosoma japonicum (S. japonicum) as measured by reduction in worm burden and host antibody, cytokines.Methods DNA vaccine pCD Sj32 was constructed. identificated and expressed. pCD Sj32 could induce substantial protective immunity against infection of S. japonicum in BALB/c mice. The best efficacy can be produced with one injection of 100?μg DNA into the quadriceps muscle, combined with challenge for 8 weeks after immunization. T lymphocyte subsets of CD 8 +, IL 2. TNF and IFN γ of experimental animal could play important roles in regulating immune functions of schistosomiasis. Results High titre of specific antibody IgG could be induced by vaccinated with pCD Sj32, and antibody can mediate macrophage to produce ADCC effects in vitro. Conclusion pCD Sj32 may represent a new approach to developing subunit vaccine.
基金This work was supported by the National Natural Science Foundation of China(31970889,31622023 to X.M.J.and 81902039 to Q.Z.L.)the Innovation Program of Shanghai Municipal Education Commission(201901070007E00022 to X.M.J.)+5 种基金the Outstanding Academic Leader Program of the Shanghai Health and Family Planning Commission(2017BR024 to X.M.J.)the Shuguang Program of the Shanghai Municipal Education Commission(17SG24 to X.M.J.)the Fundamental Research Funds for the Central Universities(X.M.J.)by a member of the Innovative Research Team of High-Level Local University in Shanghai(X.M.J.)the Key fund for basic research of Shanghai Science and Technology Commission(20JC1417700 to X.M.J.)Shanghai Municipal Natural Science Foundation(19ZR1461800 to D.D.L.).
文摘The morphological switch between yeast and hyphae of Candida albicans is essential for its interaction with the host defense system.However,the lack of understanding of host-pathogen interactions during C.albicans infection greatly hampers the development of effective immunotherapies.Here,we found that priming with the C.albicans FLO8-deficient(flo8)mutant,locked in yeast form,protected mice from subsequent lethal C.albicans infection.Deficiency of Dectin-2,a fungus-derivedα-mannan recognition receptor,completely blocked flo8 mutant-induced protection.Mechanistically,the flo8 mutant-induced Dectin-2/CARD9-mediated IL-10 production in DCs and macrophages to block thymus atrophy by inhibiting the C.albicans-induced apoptosis of thymic T cells,which facilitated the continuous output of naive T cells from the thymus to the spleen.Continuous recruitment of naive T cells to the spleen enhanced Th1-biased antifungal immune responses.Consequently,depletion of CD4^(+)T cells or blockade of IL-10 receptor function using specific antibodies in mice completely blocked the protective effects of flo8 mutant priming against C.albicans infection.Moreover,mannans exposed on the surface of the flo8 mutant were responsible for eliciting protective immunity by inhibiting the C.albicans-induced apoptosis of thymic T cells to sustain the number of naive T cells in the spleen.Importantly,priming with the flo8 mutant extensively protected mice from polymicrobial infection caused by cecal ligation and puncture(CLP)by enhancing Th1-biased immune responses.Together,our findings imply that targeting FLO8 in C.albicans elicits protective immune responses against polymicrobial infections and that mannans extracted from the flo8 mutant are potential immunotherapeutic candidate(s)for controlling infectious diseases.
基金This work was supported by the National Basic Research Program of China (2012CB932500), Funds for International Cooperation and Exchange of the National Natural Science Foundation of China (30911120482), the Program for New Century Excellent Talents in University (NCET-08-0219) and the Fundamental Research Funds for the Central Universities (HUST-2010JC024, HUST-2011TS027).
文摘Interplay between macrophages and dendritic cells in the processing and presentation of bacterial antigens for T-cell immune responses remains poorly understood. Using a Listeria monocytogenes (Lm) infection model, we demonstrate that dendritic cells (DCs) require the support of macrophages to elicit protective immunity against Lm infection. DCs themselves were inefficient at taking up Lm but capable of taking up microparticles (MPs) released by Lm-infected macrophages. These MPs transferred Lm antigens to DCs, allowing DCs to present Lm antigen to effector T cells. MP-mediated Lm antigen transfer required M HC class I participation, since M HC class I deficiency in macrophages resulted in a significant reduction of T-cell activation. Moreover, the vaccination of mice with MPs from Lm-infected macrophages produced strong protective immunity against Lm infection. We here identify an intrinsic antigen transfer program between macrophages and DCs during Lm infection, and emphasize that macrophages also play an essential role in DC-elicited Lm-specific T-cell responses.
文摘Flaviviruses comprise approximately 70 closely related RNA viruses. These include several mosquito-borne pathogens, such as yellow fever virus (YFV), dengue virus (DENV), and Japanese encephalitis virus (JEV), which can cause significant human diseases and thus are of great medical importance. Vaccines against both YFV and JEV have been used successfully in humans for decades; however, the development of a DENV vaccine has encountered considerable obstacles. Here, we review the protective immune responses elicited by the vaccine against YFV to provide some insights into the development of a protective DENV vaccine.
基金This study was supported by grants from the National Institutes of Health(AI64639 and GM84459)the core facilities of MD Anderson Cancer Center are supported by the NIH/NCI Cancer Center Support Grant(CCSG)P30CA016672.
文摘Generation and maintenance of antigen-specific effector and memory T cells are central events in immune responses against infections.We show that TNF receptor-associated factor 2(TRAF2)maintains a survival signaling axis in effector and memory CD8 T cells required for immune responses against infections.This signaling axis involves activation of Tpl2 and its downstream kinase ERK by NF-κB-inducing kinase(NIK)and degradation of the proapoptotic factor Bim.NIK mediates Tpl2 activation by stimulating the phosphorylation and degradation of the Tpl2 inhibitor p105.Interestingly,while NIK is required for Tpl2-ERK signaling under normal conditions,uncontrolled NIK activation due to loss of its negative regulator,TRAF2,causes constitutive degradation of p105 and Tpl2,leading to severe defects in ERK activation and effector/memory CD8 T cell survival.Thus,TRAF2 controls a previously unappreciated signaling axis mediating effector/memory CD8 T cell survival and protective immunity.
文摘Background Recently congenital infection with Schistosoma japonicum (S. japonicum) has been domonstrated in pigs, rabbits, mice and dogs. We explored the rabbit as an animal model for the congenital infection of schistosomiasis japonica and assessed the effect of a congenital S. japonicum infection on the resistance of rabbit kittens to a postnatal challenge infection.Methods Sixteen pregnant New Zealand white rabbits were infected with a single dose of S. japonicum cercariae. The exposed animals were divided into three groups according to the gestation age at the time of infection. Diagnosis of prenatally acquired S. japonicum infection in the rabbit kittens was primarily based on serological tests in combination with parasitological and histopathological findings. Congenitally infected kittens were challenged percutaneously with 100 S. japonicum cercariae to assess the effect of a congenital S. japonicum infection on kitten resistance to a postnatal challenge infection.Results The overall prevalence of congenital infection in offspring of infected mothers was 20% (12/60). The congenital infection rate in group L (late gestation) was much higher than in group E (early gestation) and group M (mid-gestation) (P<0.05). After a postnatal challenge infection, prenatally infected kittens had a 54.66% worm reduction rate, 41.45% egg reduction rate, and 51.76% granuloma size reduction rate compared to nave kittens.Conclusions This study demonstrates the possibility of congenital infection of S. japonicum in rabbits and the resistance of congenitally infected kittens to a postnatal challenge infection. These results have important implications not only for epidemiological investigations, but also in designing government control programs for schistosomiasis.
基金Supported by the National Natural Science Foundation of China (No. 30221003) and the Beijing Feikai Biotech Ltd
文摘Ems is a highly glycosylated envelope protein of classical swine fever virus (CSFV) with RNase ac- tivity. Ems can induce neutralizing antibodies and provide immune protection against CSFV infection. In this study, the RNase domain of the Ems was produced in Eschenchia coil. Its reactivity with CSFV-positive sera and its ability to induce antibodies and to provide protective immunity were then investigated. The serological tests showed that the prokaryotically expressed RNase domain of the Ems retained its antigenicity and in- duced high titers of humoral responses. However, only partial protection and a limited amount of neutralizing antibodies were demonstrated by an in vitro neutralization test and an immunization/challenge test. The re- sults suggest that other essential factors rather than simply enhancing the immunogenicity of Ems should be taken into consideration when Er"s is enrolled as one of the components of a candidate vaccine.