In this article,we comment on an article published in a recent issue of the World Journal of Gastroenterology.We specifically focus on the roles of human leukocyte antigen(HLA)and donor-specific antibodies(DSAs)in ped...In this article,we comment on an article published in a recent issue of the World Journal of Gastroenterology.We specifically focus on the roles of human leukocyte antigen(HLA)and donor-specific antibodies(DSAs)in pediatric liver transpl-antation(LT),as well as the relationship between immune rejection after LT and DSA.Currently,LT remains the standard of care for pediatric patients with end-stage liver disease or severe acute liver failure.However,acute and chronic re-jection continues to be a significant cause of graft dysfunction and loss.HLA mismatch significantly reduces graft survival and increases the risk of acute rejection.Among them,D→R one-way mismatch at three loci was significantly related to graft-versus-host disease incidence after LT.The adverse impact of HLA-DSAs on LT recipients is already established.Therefore,the evaluation of HLA and DSA is crucial in pediatric LT.展开更多
Antibody-mediated rejection(AMR)is one of the major causes of graft loss after transplantation.Recently,the regulation of B cell differentiation and the prevention of donor-specific antibody(DSA)production have gained...Antibody-mediated rejection(AMR)is one of the major causes of graft loss after transplantation.Recently,the regulation of B cell differentiation and the prevention of donor-specific antibody(DSA)production have gained increased attention in transplant research.Herein,we established a secondary allogeneic in vivo skin transplant model to study the effects of romidepsin(FK228)on DSA.The survival of grafted skins was monitored daily.The serum levels of DSA and the number of relevant immunocytes in the recipient spleens were evaluated by flow cytometry.Then,we isolated and purified B cells from B6mouse spleens in vitro by magnetic bead sorting.The B cells were cultured with interleukin-4(IL-4)and anti-clusters of differentiation 40(CD40)antibody with or without FK228 treatment.The immunoglobulin G1(IgG1)and IgM levels in the supernatant were evaluated by enzyme-linked immunosorbent assay(ELISA).Quantitative reverse transcription-polymerase chain reaction(RT-q PCR)and western blotting were conducted to determine the corresponding levels of messenger RNA(mRNA)and protein expression in cultured cells and the recipient spleens.The results showed that FK228 significantly improved the survival of allogeneic skin grafts.Moreover,FK228 inhibited DSA production in the serum along with the suppression of histone deacetylase 1(HADC1)and HDAC2 and the upregulation of the acetylation of histones H2A and H3.It also inhibited the differentiation of B cells to plasma cells,decreased the transcription of positive regulatory domain-containing 1(Prdm1)and X-box-binding protein 1(Xbp1),and decreased the expression of phosphorylated inositol-requiring enzyme 1α(p-IRE1α),XBP1,and B lymphocyte-induced maturation protein-1(Blimp-1).In conclusion,FK228 could decrease the production of antibodies by B cells via inhibition of the IRE1α-XBP1 signaling pathway.Thus,FK228 is considered as a promising therapeutic agent for the clinical treatment of AMR.展开更多
AIM To investigate the role of tacrolimus intra-patient variability(IPV) in adult liver-transplant recipients.METHODS We retrospectively assessed tacrolimus variability in a cohort of liver-transplant recipients and a...AIM To investigate the role of tacrolimus intra-patient variability(IPV) in adult liver-transplant recipients.METHODS We retrospectively assessed tacrolimus variability in a cohort of liver-transplant recipients and analyzed its effect on the occurrence of graft rejection and de novo donor-specific antibodies(dn DSAs), as well as graft survival during the first 2 years posttransplantation. Between 02/08 and 06/2015, 116 patients that received tacrolimus plus mycophenolate mofetil(with or without steroids) were included. RESULTS Twenty-two patients(18.5%) experienced at least one acute-rejection episode(BPAR). Predictive factors for a BPAR were a tacrolimus IPV of > 35% [OR = 3.07 95%CI(1.14-8.24), P = 0.03] or > 40% [OR = 4.16(1.38-12.50), P = 0.01), and a tacrolimus trough level of < 5 ng/mL [OR=3.68(1.3-10.4), P =0.014]. Thirteen patients(11.2%) developed at least one dn DSA during the follow-up. Tacrolimus IPV [coded as a continuous variable: OR = 1.1, 95%CI(1.0-1.12), P = 0.006] of > 35% [OR = 4.83, 95%CI(1.39-16.72), P = 0.01] and > 40% [OR = 9.73, 95%CI(2.65-35.76), P = 0.001] were identified as predictors to detect dn DSAs. IPV did not impact on patient-or graft-survival rates during the follow-up. CONCLUSION Tacrolimus-IPV could be a useful tool to identify patients with a greater risk of graft rejection and of developing a de novo DSA after liver展开更多
BACKGROUND In a previous paper,we reported a high prevalence of donor-specific antibody(DSA)in pediatric patients with chronic rejection and expressed the need for confirmation of these findings in a larger cohort.AIM...BACKGROUND In a previous paper,we reported a high prevalence of donor-specific antibody(DSA)in pediatric patients with chronic rejection and expressed the need for confirmation of these findings in a larger cohort.AIM To clarify the importance of DSAs on long-term graft survival in a larger cohort of pediatric patients.METHODS We performed a retrospective analysis of 123 pediatric liver transplantation(LT)recipients who participated in yearly follow-ups including Luminex testing for DSA at our center.The cohort was split into two groups according to the DSA status(DSA-positive n=54,DSA-negative n=69).Groups were compared with regard to liver function,biopsy findings,graft survival,need for re-LT and immunosuppressive medication.RESULTS DSA-positive pediatric patients showed a higher prevalence of chronic rejection(P=0.01),fibrosis(P<0.001)and re-transplantation(P=0.018)than DSA-negative patients.Class II DSAs particularly influenced graft survival.Alleles DQ2,DQ7,DQ8 and DQ9 might serve as indicators for the risk of chronic rejection and/or allograft fibrosis.Mean fluorescence intensity levels and DSA number did not impact graft survival.Previous episodes of chronic rejection might lead to DSA development.CONCLUSION DSA prevalence significantly affected long-term liver allograft performance and liver allograft survival in our cohort of pediatric LT.Screening for class II DSAs in combination with assessment of protocol liver biopsies for chronic antibodymediated rejection improved early identification of patients at risk of graft loss.展开更多
Allo-antibodies, particularly when donor specific, are one of the most important factors that cause both early and late graft dysfunction. The authors review the current state of the art concerning this important issu...Allo-antibodies, particularly when donor specific, are one of the most important factors that cause both early and late graft dysfunction. The authors review the current state of the art concerning this important issue in renal transplantation. Many antibodies have been recognized as mediators of renal injury. In particular donorspecific-Human Leukocyte Antigens antibodies appear to play a major role. New techniques, such as solid phase techniques and Luminex, have revealed these antibodies from patient sera. Other new techniques have uncovered alloantibodies and signs of complement activation in renal biopsy specimens. It has been acknowledged that the old concept of chronic renal injury caused by calcineurine inhibitors toxicity should be replaced in many cases by alloantibodies acting against the graft. In addition, the number of patients on waiting lists with preformed anti-human leukocyte antigens(HLA) antibodies is increasing, primarily from patients with a history of renal transplant failure already been sensitized. We should distinguish early and late acute antibody-mediated rejection from chronic antibody-mediated rejection. The latter often manifets late during the course of the posttransplant period and may be difficult to recognize if specific techniques are not applied. Different therapeutic strategies are used to control antibody-induced damage.These strategies may be applied prior to transplantation or, in the case of acute antibody-mediated rejection, after transplantation. Many new drugs are appearing at the horizon; however, these drugs are far from the clinic because they are in phase Ⅰ-Ⅱ of clinical trials. Thus the pipeline for the near future appears almost empty.展开更多
Antibody-mediated rejection(AMR) caused by donorspecific anti-human leukocyte antigen antibodies(DSA) is widely accepted to be a risk factor for decreased graft survival after kidney transplantation. This entity also ...Antibody-mediated rejection(AMR) caused by donorspecific anti-human leukocyte antigen antibodies(DSA) is widely accepted to be a risk factor for decreased graft survival after kidney transplantation. This entity also plays a pathogenic role in other solid organ transplants as it appears to be an increasingly common cause of heart graft dysfunction and an emerging issue in lung transplantation. In contrast, the liver appears relatively resistant to DSA-mediated injury. This "immune-tolerance" liver property has been sustained by a low rate of liver graft loss in patients with preformed DSA and by the intrinsic liver characteristics that favor the absorption and elimination of DSA; however, alloantibody-mediated adverse consequences are increasingly being recognized, and several cases of acute AMR after ABO-compatible liver transplant(LT) have been reported. Furthermore, the availability of new solid-phase assays, allowing the detection of low titers of DSA and the refinement of objective diagnostic criteria for AMR in solid organ transplants and particularly in LT, have improved the recognition and management of this entity. A cost-effective strategy of DSA monitoring, avoidance of class Ⅱ human leukocyte antigen mismatching, judicious immunosuppression attached to a higher level of clinical suspicion of AMR, particularly in cases unresponsive to conventional antirejection therapy, can allow a rational approach to this threat.展开更多
AIM To analyze the clinical impact of preformed antiH LA-Cw vs antiH LA-A and/or-B donor-specific antibodies(DSA) in kidney transplantation.METHODS Retrospective study, comparing 12 patients transplanted with DSA excl...AIM To analyze the clinical impact of preformed antiH LA-Cw vs antiH LA-A and/or-B donor-specific antibodies(DSA) in kidney transplantation.METHODS Retrospective study, comparing 12 patients transplanted with DSA exclusively antiH LA-Cw with 23 patients with preformed DSA antiH LA-A and/or B.RESULTS One year after transplantation there were no differencesin terms of acute rejection between the two groups(3 and 6 cases, respectively in the DSA-Cw and the DSA-A-B groups; P = 1). At one year, eG FR was not significantly different between groups(median 59 mL /min in DSA-Cw group, compared to median 51 mL /min in DSA-A-B group, P = 0.192). Moreover, kidney graft survival was similar between groups at 5-years(100% in DSA-Cw group vs 91% in DSA-A-B group, P = 0.528). The sole independent predictor of antibody mediated rejection(AMR) incidence was DSA strength(HR = 1.07 per 1000 increase in MFI, P = 0.034). AMR was associated with shortened graft survival at 5-years, with 75% and 100% grafts surviving in patients with or without AMR, respectively(Log-rank P = 0.005).CONCLUSION Our data indicate that DSA-Cw are associated with an identical risk of AMR and impact on graft function in comparison with "classical" class I DSA.展开更多
In medical research,there are times when the introduction of a new tool can launch scientific discovery in new directions.While antibody development may be considered mundane,in the field of glucocerebrosidase(GCase)r...In medical research,there are times when the introduction of a new tool can launch scientific discovery in new directions.While antibody development may be considered mundane,in the field of glucocerebrosidase(GCase)research,the dearth of validated antibodies for different applications has impeded progress in studies of disease pathogenesis and therapeutic development.The recent introduction of new,rigorously evaluated antibodies can now propel research into the link between glucocerebrosidase and Parkinson’s disease(PD)as well as aspects of the pathobiology of Gaucher disease(Jong et al.,2024).展开更多
The role of antibodies in kidney transplant(KT)has evolved significantly over the past few decades.This role of antibodies in KT is multifaceted,encompassing both the challenges they pose in terms of antibody-mediated...The role of antibodies in kidney transplant(KT)has evolved significantly over the past few decades.This role of antibodies in KT is multifaceted,encompassing both the challenges they pose in terms of antibody-mediated rejection(AMR)and the opportunities for improving transplant outcomes through better detection,prevention,and treatment strategies.As our understanding of the immunological mechanisms continues to evolve,so too will the approaches to managing and harnessing the power of antibodies in KT,ultimately leading to improved patient and graft survival.This narrative review explores the multifaceted roles of antibodies in KT,including their involvement in rejection mechanisms,advancements in desensitization protocols,AMR treatments,and their potential role in monitoring and improving graft survival.展开更多
BACKGROUND At the end of December 2019,the world faced severe acute respiratory syndrome-coronavirus 2(SARS-CoV-2),which led to the outbreak of coronavirus disease 2019(COVID-19),associated with respiratory issues.Thi...BACKGROUND At the end of December 2019,the world faced severe acute respiratory syndrome-coronavirus 2(SARS-CoV-2),which led to the outbreak of coronavirus disease 2019(COVID-19),associated with respiratory issues.This virus has shown significant challenges,especially for senior citizens,patients with other underlying illnesses,or those with a sedentary lifestyle.Serological tests conducted early on have helped identify how the virus is transmitted and how to curb its spread.The study hypothesis was that the rapid serological test for SARS-CoV-2 antibodies could indicate the immunoreactive profile during the COVID-19 pandemic in a university population.AIM To conduct active surveillance for serological expression of anti-SARS-CoV-2 antibodies in individuals within a university setting during the COVID-19 pandemic.METHODS This sectional study by convenience sampling was conducted in a large university in Niteroi-RJ,Brazil,from March 2021 to July 2021.The study population consisted of students,faculty,and administrative staff employed by the university.A total of 3433 faculty members,60703 students,and 3812 administrative staff were invited to participate.Data were gathered through rapid serological tests to detect immunoglobulin(Ig)M and IgG against SARS-CoV-2.Theχ²or Fisher's exact test was used to conduct statistical analysis.A 0.20 significance level was adopted for variable selection in a multiple logistic regression model to evaluate associations.RESULTS A total of 1648 individuals were enrolled in the study.The proportion of COVID-19 positivity was 164/1648(9.8%).The adjusted logistic model indicate a positive association between the expression of IgM or IgG and age[odds ratio(OR)=1.16,95%CI:1.02-1.31](P<0.0024),individuals who had been in contact with a COVID-19-positive case(OR=3.49,95%CI:2.34-5.37)(P<0.001),those who had received the COVID-19 vaccine(OR=2.33,95%CI:1.61-3.35)(P<0.001)and social isolation(OR=0.59,95%CI:0.41-0.84)(P<0.004).The likelihood of showing a positive result increased by 16%with every ten-year increment.Conversely,adherence to social distancing measures decreased the likelihood by 41%.CONCLUSION These findings evidenced that the population became more exposed to the virus as individuals discontinued social distancing practices,thereby increasing the risk of infection for themselves.展开更多
Antibodies as therapeutic agents are mostly used in oncology, as illustrated by their applications in lymphoma, breast cancer or colorectal cancer. This review provides a brief historical sketch of the development of ...Antibodies as therapeutic agents are mostly used in oncology, as illustrated by their applications in lymphoma, breast cancer or colorectal cancer. This review provides a brief historical sketch of the development of monoclonal antibodies for cancer treatment and summarizes the most significant clinical data for the best-established reagents to date. It also discusses strategies to improve the anti-tumor efficacy of antibody therapy, including antibody gene therapy and exploitation of bone marrow derived primary mesenchymal stem cells as the antibody gene transporter.展开更多
Testis-specific protease 50 (TSP50) is a testis-specific oncogene, which is abnormally activated in most tested patients with breast cancer. This property makes it an attractive molecular marker and a promising targ...Testis-specific protease 50 (TSP50) is a testis-specific oncogene, which is abnormally activated in most tested patients with breast cancer. This property makes it an attractive molecular marker and a promising target for the diagnosis and therapy of breast cancer. In order to obtain the protective and specific polyclonal antibodies for further research, TSPS0 cDNA was amplified by RT-PCR from normal human testicular tissue, and inserted into eukaryotic expression vector PeDNA3.1. Rabbit anti-TSPS0 polyclonal antibodies were prepared by means of intramuscular injection of peDNA3.1-TSPS0 into the rabbits. Titem of the anti-sera were measured by ELISA and Western blotting with the E. coli cell lysate containing the induced GST-TSPS0 fusion protein as an antigen. In addition, we examined the expression of TSPS0 in both breast cancer cell line MCF-7 and breast cancer tissue by immunofluorescent and immunohistochemistry analysis.展开更多
Due to advances in modern medicine,liver transplantation has revolutionised the prognosis of many previously incurable liver diseases.This progress has largely been due to advances in immunosuppressant therapy.However...Due to advances in modern medicine,liver transplantation has revolutionised the prognosis of many previously incurable liver diseases.This progress has largely been due to advances in immunosuppressant therapy.However,despite the judicious use of immunosuppression,many liver transplant recipients still experience complications such as rejection,which necessitates diagnosis via invasive liver biopsy.There is a clear need for novel,minimally-invasive tests to optimise immunosuppression and improve patient outcomes.An emerging biomarker in this‘‘precision medicine’‘liver transplantation field is that of donorspecific cell free DNA.In this review,we detail the background and methods of detecting this biomarker,examine its utility in liver transplantation and discuss future research directions that may be most impactful.展开更多
T cell activation following alloantigen recognition plays a critical role in the development of the rejection in all solid organ, tissue and cell transplantation. A recombinant molecule, cytotoxic T lymphocyte antigen...T cell activation following alloantigen recognition plays a critical role in the development of the rejection in all solid organ, tissue and cell transplantation. A recombinant molecule, cytotoxic T lymphocyte antigen 4 antibody (CTLA-4Ig), is known to induce to T-cell into "anergy" by blocking the costimulatory B7-CD28 interaction. Either systemic or localized administration of CTLA-Ig has been shown to prolong allograft survival and induce donor-specific tolerance in some transplant models. In this study, we characterized the expression and immunosuppressive effectiveness of adenoviral-mediated CTLA-4Ig gene transfer. We demonstrated transduction of the allografts with AdCTLA-4Ig resulted in localized expression, permanent graft survival and stable donor-specific tolerance. In addition, by performing simultaneous dual-organ through a local expression of CTLA-4Ig via adenoviral-mediated transplantation, we targeted on immunosuppression gene transfer into pancreatic allografts.展开更多
The γc cytokines play an important role in proliferation and survival of T cells. Blocking the γc signals can cause the activated donor-reactive T cells losing the ability to proliferate, and getting into apoptosis ...The γc cytokines play an important role in proliferation and survival of T cells. Blocking the γc signals can cause the activated donor-reactive T cells losing the ability to proliferate, and getting into apoptosis pathway, which contributes to induction of the peripheral tolerance. In this study, we induced the transplant tolerance through blocking the γc in combination with donor-specific transfusion (DST) in the cardiac transplantation. Following DST, on the day 2, 4 and 6, C57BL/6 recipients received anti-γc monoclonal antibodies (mAbs) injection, and those in control group were not given anti-γc mAbs. On the day 7, Balb/c cardiac allografts were transplanted. All recipients in experimental group accepted cardiac allografts over 30 days, and two of them accepted allografts without rejection until sacrifice on the 120 day. Animals only receiving DST rejected grafts within 5 days, and the mice receiving cardiac transplantation alone rejected grafts within 9 days. Our study showed that blockade of γc signaling combined with DST significantly prolonged allograft survival, which was probably associated with inhibition of antigen-specific T-cell proliferation and induction of apoptosis.展开更多
A monoclonal antibody was first prepared by fusion of mouse myeloma cells (SP2/0-Ag-14) with spleen cells isolated from male BALB/ c mice immunized with spermidine-bovine serum albumin conjugate (SPD- BSA). The hybrid...A monoclonal antibody was first prepared by fusion of mouse myeloma cells (SP2/0-Ag-14) with spleen cells isolated from male BALB/ c mice immunized with spermidine-bovine serum albumin conjugate (SPD- BSA). The hybridoma cell line producing antibody specific for spermidine was cultured in vitro and after i. p. into mice, the ascitic fluid gave suitably high dilution titres (1: 106) by enzyme immunoassay. This monoclonal antibody is of IgG1 class and the bimolecular compleex with molecular weight of 52KD and 27 KD. The monoclonal antibody was clearly specific to spermidine comparing with spermine or putriscine. Monclonal antibody may prove to be useful in the rapid diagnosis and evaluation of patients with cancer.展开更多
Objective: To isolate murine anti endotoxin single chain phage antibody from a constructed library. Methods: Total RNA was firstly extracted from murine splenic cells and mRNA was reverse-transcribed into cDNA. Then t...Objective: To isolate murine anti endotoxin single chain phage antibody from a constructed library. Methods: Total RNA was firstly extracted from murine splenic cells and mRNA was reverse-transcribed into cDNA. Then the designed primers were used to amplify the variable region genes of the heavy and light chain (VH, VL) with polymerase chain reaction. The linker was used to assemble the VH and VL into ScFv, and the NotI and SfiI restriction enzymes were used to digest the ScFv in order to ligate into the pCANTAB5E phagemid vector that was already digested with the same restriction enzymes. The ligated vector was then introduced into competent E.coli TG1 cells to construct a single-chain phage antibody library. After rescued with M13KO7 helper phage, recombinant phages displaying ScFv fragments were harvested from the supernatant and selected with endotoxin. The enriched positive clones were reinfected into TG1 cells. Finally, 190 clones were randomly selected to detect the anti endotoxin antibody with indirect ELISA. Results: The titer of anti endotoxin in murine sera was 1:12,800. The concentration of total RNA was 12.38 μg/ml. 1.9×107 clones were obtained after transformed into TG1. 3×104 colonies were gotten after one round panning. Two positive colonies were confirmed with indirect ELISA among 190 randomly selected colonies. Conclusion: A 1.9×107 murine anti endotoxin single chain phage antibody library was successfully constructed. Two anti endotoxin antibodies were obtained from the library.展开更多
Anti-ganglioside antibodies are associated with delayed/poor clinical recovery in Guillain-Barrèsyndrome,mostly related to halted axon regeneration.Cross-linking of cell surface gangliosides by anti-ganglioside a...Anti-ganglioside antibodies are associated with delayed/poor clinical recovery in Guillain-Barrèsyndrome,mostly related to halted axon regeneration.Cross-linking of cell surface gangliosides by anti-ganglioside antibodies triggers inhibition of nerve repair in in vitro and in vivo paradigms of axon regeneration.These effects involve the activation of the small GTPase Rho A/ROCK signaling pathways,which negatively modulate growth cone cytoskeleton,similarly to well stablished inhibitors of axon regeneration described so far.The aim of this work was to perform a proof of concept study to demonstrate the effectiveness of Y-27632,a selective pharmacological inhibitor of ROCK,in a mouse model of axon regeneration of peripheral nerves,where the passive immunization with a monoclonal antibody targeting gangliosides GD1a and GT1b was previously reported to exert a potent inhibitory effect on regeneration of both myelinated and unmyelinated fibers.Our results demonstrate a differential sensitivity of myelinated and unmyelinated axons to the pro-regenerative effect of Y-27632.Treatment with a total dosage of 9 mg/kg of Y-27632 resulted in a complete prevention of anti-GD1a/GT1b monoclonal antibody-mediated inhibition of axon regeneration of unmyelinated fibers to skin and the functional recovery of mechanical cutaneous sensitivity.In contrast,the same dose showed toxic effects on the regeneration of myelinated fibers.Interestingly,scale down of the dosage of Y-27632 to 5 mg/kg resulted in a significant although not complete recovery of regenerated myelinated axons exposed to anti-GD1a/GT1b monoclonal antibody in the absence of toxicity in animals exposed to only Y-27632.Overall,these findings confirm the in vivo participation of Rho A/ROCK signaling pathways in the molecular mechanisms associated with the inhibition of axon regeneration induced by anti-GD1a/GT1b monoclonal antibody.Our findings open the possibility of therapeutic pharmacological intervention targeting Rho A/Rock pathway in immune neuropathies associated with the presence of anti-ganglioside antibodies and delayed or incomplete clinical recovery after injury in the peripheral nervous system.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
The cytokine repertoire of ADP/ATP carrier-specific humoral immune responses and the cytokine-dependent anti-ADP/ATP carrier antibody IgG subclasses were examined in a cohort of ADP/ATP carrier-immunized BALB/c mice t...The cytokine repertoire of ADP/ATP carrier-specific humoral immune responses and the cytokine-dependent anti-ADP/ATP carrier antibody IgG subclasses were examined in a cohort of ADP/ATP carrier-immunized BALB/c mice treated with anti-CD4 monoclonal antibody. Eighteen male BALB/c mice (6–8 weeks old) were randomized into 3 groups: dilated cardiomyopathy (DCM) group, DCM-tolerance (Tol) group and control group. The mice in DCM group were immunized with the peptides derived from human ADP/ATP carrier protein for 6 months and mice in the control group were sham-immunized, while the mice in DCM-Tol group were immunized with ADP/ATP carrier protein and anti-CD4 McAb simultaneously. Serum autoantibody against ADP/ATP carrier and IgG subclasses were measured by ELISA, intracellular cytokines IFN-γ and IL-4 of Th cells were moni- tored with flow cytometry, and splenic T cell cytokines IFN-γ, IL-2, IL-4 and IL-6 were detected by using real-time fluorescent quantitative PCR. The results showed that the autoantibody against ADP/ATP carrier was found in all mice in DCM group, and the antibody level, serum IgG1 and IgG2a subclasses, cytokines in T cells and Th cells were all elevated in DCM group, as compared with those in control group (P〈0.01). On the other hand, in DCM-Tol group, the autoantibody level and contents of all the cytokines were significantly different from those in DCM group (P〈0.01), and were close to those in control group. And the levels of IgG1, IgG2a, IgG2b and IgG3 were influenced, to varying degrees, by anti-CD4 McAb as compared with those in DCM group. All these four types of IgG subclasses were substantially decreased in DCM-Tol group as compared with DCM group. It is concluded that the treatment with anti-CD4 McAb could prevent the activation of T cells, reverse the abnormal secretion of cytokines and the imbalance between Th1/Th2 cell subsets and abnormal production of autoantibody against ADP/ATP carrier, and eventually avoid myocardial injuries.展开更多
文摘In this article,we comment on an article published in a recent issue of the World Journal of Gastroenterology.We specifically focus on the roles of human leukocyte antigen(HLA)and donor-specific antibodies(DSAs)in pediatric liver transpl-antation(LT),as well as the relationship between immune rejection after LT and DSA.Currently,LT remains the standard of care for pediatric patients with end-stage liver disease or severe acute liver failure.However,acute and chronic re-jection continues to be a significant cause of graft dysfunction and loss.HLA mismatch significantly reduces graft survival and increases the risk of acute rejection.Among them,D→R one-way mismatch at three loci was significantly related to graft-versus-host disease incidence after LT.The adverse impact of HLA-DSAs on LT recipients is already established.Therefore,the evaluation of HLA and DSA is crucial in pediatric LT.
基金supported by the National Natural Science Foundation of China(Nos.81873511 and 81471587)。
文摘Antibody-mediated rejection(AMR)is one of the major causes of graft loss after transplantation.Recently,the regulation of B cell differentiation and the prevention of donor-specific antibody(DSA)production have gained increased attention in transplant research.Herein,we established a secondary allogeneic in vivo skin transplant model to study the effects of romidepsin(FK228)on DSA.The survival of grafted skins was monitored daily.The serum levels of DSA and the number of relevant immunocytes in the recipient spleens were evaluated by flow cytometry.Then,we isolated and purified B cells from B6mouse spleens in vitro by magnetic bead sorting.The B cells were cultured with interleukin-4(IL-4)and anti-clusters of differentiation 40(CD40)antibody with or without FK228 treatment.The immunoglobulin G1(IgG1)and IgM levels in the supernatant were evaluated by enzyme-linked immunosorbent assay(ELISA).Quantitative reverse transcription-polymerase chain reaction(RT-q PCR)and western blotting were conducted to determine the corresponding levels of messenger RNA(mRNA)and protein expression in cultured cells and the recipient spleens.The results showed that FK228 significantly improved the survival of allogeneic skin grafts.Moreover,FK228 inhibited DSA production in the serum along with the suppression of histone deacetylase 1(HADC1)and HDAC2 and the upregulation of the acetylation of histones H2A and H3.It also inhibited the differentiation of B cells to plasma cells,decreased the transcription of positive regulatory domain-containing 1(Prdm1)and X-box-binding protein 1(Xbp1),and decreased the expression of phosphorylated inositol-requiring enzyme 1α(p-IRE1α),XBP1,and B lymphocyte-induced maturation protein-1(Blimp-1).In conclusion,FK228 could decrease the production of antibodies by B cells via inhibition of the IRE1α-XBP1 signaling pathway.Thus,FK228 is considered as a promising therapeutic agent for the clinical treatment of AMR.
文摘AIM To investigate the role of tacrolimus intra-patient variability(IPV) in adult liver-transplant recipients.METHODS We retrospectively assessed tacrolimus variability in a cohort of liver-transplant recipients and analyzed its effect on the occurrence of graft rejection and de novo donor-specific antibodies(dn DSAs), as well as graft survival during the first 2 years posttransplantation. Between 02/08 and 06/2015, 116 patients that received tacrolimus plus mycophenolate mofetil(with or without steroids) were included. RESULTS Twenty-two patients(18.5%) experienced at least one acute-rejection episode(BPAR). Predictive factors for a BPAR were a tacrolimus IPV of > 35% [OR = 3.07 95%CI(1.14-8.24), P = 0.03] or > 40% [OR = 4.16(1.38-12.50), P = 0.01), and a tacrolimus trough level of < 5 ng/mL [OR=3.68(1.3-10.4), P =0.014]. Thirteen patients(11.2%) developed at least one dn DSA during the follow-up. Tacrolimus IPV [coded as a continuous variable: OR = 1.1, 95%CI(1.0-1.12), P = 0.006] of > 35% [OR = 4.83, 95%CI(1.39-16.72), P = 0.01] and > 40% [OR = 9.73, 95%CI(2.65-35.76), P = 0.001] were identified as predictors to detect dn DSAs. IPV did not impact on patient-or graft-survival rates during the follow-up. CONCLUSION Tacrolimus-IPV could be a useful tool to identify patients with a greater risk of graft rejection and of developing a de novo DSA after liver
文摘BACKGROUND In a previous paper,we reported a high prevalence of donor-specific antibody(DSA)in pediatric patients with chronic rejection and expressed the need for confirmation of these findings in a larger cohort.AIM To clarify the importance of DSAs on long-term graft survival in a larger cohort of pediatric patients.METHODS We performed a retrospective analysis of 123 pediatric liver transplantation(LT)recipients who participated in yearly follow-ups including Luminex testing for DSA at our center.The cohort was split into two groups according to the DSA status(DSA-positive n=54,DSA-negative n=69).Groups were compared with regard to liver function,biopsy findings,graft survival,need for re-LT and immunosuppressive medication.RESULTS DSA-positive pediatric patients showed a higher prevalence of chronic rejection(P=0.01),fibrosis(P<0.001)and re-transplantation(P=0.018)than DSA-negative patients.Class II DSAs particularly influenced graft survival.Alleles DQ2,DQ7,DQ8 and DQ9 might serve as indicators for the risk of chronic rejection and/or allograft fibrosis.Mean fluorescence intensity levels and DSA number did not impact graft survival.Previous episodes of chronic rejection might lead to DSA development.CONCLUSION DSA prevalence significantly affected long-term liver allograft performance and liver allograft survival in our cohort of pediatric LT.Screening for class II DSAs in combination with assessment of protocol liver biopsies for chronic antibodymediated rejection improved early identification of patients at risk of graft loss.
文摘Allo-antibodies, particularly when donor specific, are one of the most important factors that cause both early and late graft dysfunction. The authors review the current state of the art concerning this important issue in renal transplantation. Many antibodies have been recognized as mediators of renal injury. In particular donorspecific-Human Leukocyte Antigens antibodies appear to play a major role. New techniques, such as solid phase techniques and Luminex, have revealed these antibodies from patient sera. Other new techniques have uncovered alloantibodies and signs of complement activation in renal biopsy specimens. It has been acknowledged that the old concept of chronic renal injury caused by calcineurine inhibitors toxicity should be replaced in many cases by alloantibodies acting against the graft. In addition, the number of patients on waiting lists with preformed anti-human leukocyte antigens(HLA) antibodies is increasing, primarily from patients with a history of renal transplant failure already been sensitized. We should distinguish early and late acute antibody-mediated rejection from chronic antibody-mediated rejection. The latter often manifets late during the course of the posttransplant period and may be difficult to recognize if specific techniques are not applied. Different therapeutic strategies are used to control antibody-induced damage.These strategies may be applied prior to transplantation or, in the case of acute antibody-mediated rejection, after transplantation. Many new drugs are appearing at the horizon; however, these drugs are far from the clinic because they are in phase Ⅰ-Ⅱ of clinical trials. Thus the pipeline for the near future appears almost empty.
文摘Antibody-mediated rejection(AMR) caused by donorspecific anti-human leukocyte antigen antibodies(DSA) is widely accepted to be a risk factor for decreased graft survival after kidney transplantation. This entity also plays a pathogenic role in other solid organ transplants as it appears to be an increasingly common cause of heart graft dysfunction and an emerging issue in lung transplantation. In contrast, the liver appears relatively resistant to DSA-mediated injury. This "immune-tolerance" liver property has been sustained by a low rate of liver graft loss in patients with preformed DSA and by the intrinsic liver characteristics that favor the absorption and elimination of DSA; however, alloantibody-mediated adverse consequences are increasingly being recognized, and several cases of acute AMR after ABO-compatible liver transplant(LT) have been reported. Furthermore, the availability of new solid-phase assays, allowing the detection of low titers of DSA and the refinement of objective diagnostic criteria for AMR in solid organ transplants and particularly in LT, have improved the recognition and management of this entity. A cost-effective strategy of DSA monitoring, avoidance of class Ⅱ human leukocyte antigen mismatching, judicious immunosuppression attached to a higher level of clinical suspicion of AMR, particularly in cases unresponsive to conventional antirejection therapy, can allow a rational approach to this threat.
文摘AIM To analyze the clinical impact of preformed antiH LA-Cw vs antiH LA-A and/or-B donor-specific antibodies(DSA) in kidney transplantation.METHODS Retrospective study, comparing 12 patients transplanted with DSA exclusively antiH LA-Cw with 23 patients with preformed DSA antiH LA-A and/or B.RESULTS One year after transplantation there were no differencesin terms of acute rejection between the two groups(3 and 6 cases, respectively in the DSA-Cw and the DSA-A-B groups; P = 1). At one year, eG FR was not significantly different between groups(median 59 mL /min in DSA-Cw group, compared to median 51 mL /min in DSA-A-B group, P = 0.192). Moreover, kidney graft survival was similar between groups at 5-years(100% in DSA-Cw group vs 91% in DSA-A-B group, P = 0.528). The sole independent predictor of antibody mediated rejection(AMR) incidence was DSA strength(HR = 1.07 per 1000 increase in MFI, P = 0.034). AMR was associated with shortened graft survival at 5-years, with 75% and 100% grafts surviving in patients with or without AMR, respectively(Log-rank P = 0.005).CONCLUSION Our data indicate that DSA-Cw are associated with an identical risk of AMR and impact on graft function in comparison with "classical" class I DSA.
文摘In medical research,there are times when the introduction of a new tool can launch scientific discovery in new directions.While antibody development may be considered mundane,in the field of glucocerebrosidase(GCase)research,the dearth of validated antibodies for different applications has impeded progress in studies of disease pathogenesis and therapeutic development.The recent introduction of new,rigorously evaluated antibodies can now propel research into the link between glucocerebrosidase and Parkinson’s disease(PD)as well as aspects of the pathobiology of Gaucher disease(Jong et al.,2024).
文摘The role of antibodies in kidney transplant(KT)has evolved significantly over the past few decades.This role of antibodies in KT is multifaceted,encompassing both the challenges they pose in terms of antibody-mediated rejection(AMR)and the opportunities for improving transplant outcomes through better detection,prevention,and treatment strategies.As our understanding of the immunological mechanisms continues to evolve,so too will the approaches to managing and harnessing the power of antibodies in KT,ultimately leading to improved patient and graft survival.This narrative review explores the multifaceted roles of antibodies in KT,including their involvement in rejection mechanisms,advancements in desensitization protocols,AMR treatments,and their potential role in monitoring and improving graft survival.
文摘BACKGROUND At the end of December 2019,the world faced severe acute respiratory syndrome-coronavirus 2(SARS-CoV-2),which led to the outbreak of coronavirus disease 2019(COVID-19),associated with respiratory issues.This virus has shown significant challenges,especially for senior citizens,patients with other underlying illnesses,or those with a sedentary lifestyle.Serological tests conducted early on have helped identify how the virus is transmitted and how to curb its spread.The study hypothesis was that the rapid serological test for SARS-CoV-2 antibodies could indicate the immunoreactive profile during the COVID-19 pandemic in a university population.AIM To conduct active surveillance for serological expression of anti-SARS-CoV-2 antibodies in individuals within a university setting during the COVID-19 pandemic.METHODS This sectional study by convenience sampling was conducted in a large university in Niteroi-RJ,Brazil,from March 2021 to July 2021.The study population consisted of students,faculty,and administrative staff employed by the university.A total of 3433 faculty members,60703 students,and 3812 administrative staff were invited to participate.Data were gathered through rapid serological tests to detect immunoglobulin(Ig)M and IgG against SARS-CoV-2.Theχ²or Fisher's exact test was used to conduct statistical analysis.A 0.20 significance level was adopted for variable selection in a multiple logistic regression model to evaluate associations.RESULTS A total of 1648 individuals were enrolled in the study.The proportion of COVID-19 positivity was 164/1648(9.8%).The adjusted logistic model indicate a positive association between the expression of IgM or IgG and age[odds ratio(OR)=1.16,95%CI:1.02-1.31](P<0.0024),individuals who had been in contact with a COVID-19-positive case(OR=3.49,95%CI:2.34-5.37)(P<0.001),those who had received the COVID-19 vaccine(OR=2.33,95%CI:1.61-3.35)(P<0.001)and social isolation(OR=0.59,95%CI:0.41-0.84)(P<0.004).The likelihood of showing a positive result increased by 16%with every ten-year increment.Conversely,adherence to social distancing measures decreased the likelihood by 41%.CONCLUSION These findings evidenced that the population became more exposed to the virus as individuals discontinued social distancing practices,thereby increasing the risk of infection for themselves.
文摘Antibodies as therapeutic agents are mostly used in oncology, as illustrated by their applications in lymphoma, breast cancer or colorectal cancer. This review provides a brief historical sketch of the development of monoclonal antibodies for cancer treatment and summarizes the most significant clinical data for the best-established reagents to date. It also discusses strategies to improve the anti-tumor efficacy of antibody therapy, including antibody gene therapy and exploitation of bone marrow derived primary mesenchymal stem cells as the antibody gene transporter.
文摘Testis-specific protease 50 (TSP50) is a testis-specific oncogene, which is abnormally activated in most tested patients with breast cancer. This property makes it an attractive molecular marker and a promising target for the diagnosis and therapy of breast cancer. In order to obtain the protective and specific polyclonal antibodies for further research, TSPS0 cDNA was amplified by RT-PCR from normal human testicular tissue, and inserted into eukaryotic expression vector PeDNA3.1. Rabbit anti-TSPS0 polyclonal antibodies were prepared by means of intramuscular injection of peDNA3.1-TSPS0 into the rabbits. Titem of the anti-sera were measured by ELISA and Western blotting with the E. coli cell lysate containing the induced GST-TSPS0 fusion protein as an antigen. In addition, we examined the expression of TSPS0 in both breast cancer cell line MCF-7 and breast cancer tissue by immunofluorescent and immunohistochemistry analysis.
基金The University of Melbourne,Parkville 3000,VIC,Australia。
文摘Due to advances in modern medicine,liver transplantation has revolutionised the prognosis of many previously incurable liver diseases.This progress has largely been due to advances in immunosuppressant therapy.However,despite the judicious use of immunosuppression,many liver transplant recipients still experience complications such as rejection,which necessitates diagnosis via invasive liver biopsy.There is a clear need for novel,minimally-invasive tests to optimise immunosuppression and improve patient outcomes.An emerging biomarker in this‘‘precision medicine’‘liver transplantation field is that of donorspecific cell free DNA.In this review,we detail the background and methods of detecting this biomarker,examine its utility in liver transplantation and discuss future research directions that may be most impactful.
文摘T cell activation following alloantigen recognition plays a critical role in the development of the rejection in all solid organ, tissue and cell transplantation. A recombinant molecule, cytotoxic T lymphocyte antigen 4 antibody (CTLA-4Ig), is known to induce to T-cell into "anergy" by blocking the costimulatory B7-CD28 interaction. Either systemic or localized administration of CTLA-Ig has been shown to prolong allograft survival and induce donor-specific tolerance in some transplant models. In this study, we characterized the expression and immunosuppressive effectiveness of adenoviral-mediated CTLA-4Ig gene transfer. We demonstrated transduction of the allografts with AdCTLA-4Ig resulted in localized expression, permanent graft survival and stable donor-specific tolerance. In addition, by performing simultaneous dual-organ through a local expression of CTLA-4Ig via adenoviral-mediated transplantation, we targeted on immunosuppression gene transfer into pancreatic allografts.
基金supported by grants from the National Natural Sciences Foundation of China (No. 30500468 and 30700768)
文摘The γc cytokines play an important role in proliferation and survival of T cells. Blocking the γc signals can cause the activated donor-reactive T cells losing the ability to proliferate, and getting into apoptosis pathway, which contributes to induction of the peripheral tolerance. In this study, we induced the transplant tolerance through blocking the γc in combination with donor-specific transfusion (DST) in the cardiac transplantation. Following DST, on the day 2, 4 and 6, C57BL/6 recipients received anti-γc monoclonal antibodies (mAbs) injection, and those in control group were not given anti-γc mAbs. On the day 7, Balb/c cardiac allografts were transplanted. All recipients in experimental group accepted cardiac allografts over 30 days, and two of them accepted allografts without rejection until sacrifice on the 120 day. Animals only receiving DST rejected grafts within 5 days, and the mice receiving cardiac transplantation alone rejected grafts within 9 days. Our study showed that blockade of γc signaling combined with DST significantly prolonged allograft survival, which was probably associated with inhibition of antigen-specific T-cell proliferation and induction of apoptosis.
文摘A monoclonal antibody was first prepared by fusion of mouse myeloma cells (SP2/0-Ag-14) with spleen cells isolated from male BALB/ c mice immunized with spermidine-bovine serum albumin conjugate (SPD- BSA). The hybridoma cell line producing antibody specific for spermidine was cultured in vitro and after i. p. into mice, the ascitic fluid gave suitably high dilution titres (1: 106) by enzyme immunoassay. This monoclonal antibody is of IgG1 class and the bimolecular compleex with molecular weight of 52KD and 27 KD. The monoclonal antibody was clearly specific to spermidine comparing with spermine or putriscine. Monclonal antibody may prove to be useful in the rapid diagnosis and evaluation of patients with cancer.
基金This work was supported by the National Natural Science Foundation (No. 39570042).
文摘Objective: To isolate murine anti endotoxin single chain phage antibody from a constructed library. Methods: Total RNA was firstly extracted from murine splenic cells and mRNA was reverse-transcribed into cDNA. Then the designed primers were used to amplify the variable region genes of the heavy and light chain (VH, VL) with polymerase chain reaction. The linker was used to assemble the VH and VL into ScFv, and the NotI and SfiI restriction enzymes were used to digest the ScFv in order to ligate into the pCANTAB5E phagemid vector that was already digested with the same restriction enzymes. The ligated vector was then introduced into competent E.coli TG1 cells to construct a single-chain phage antibody library. After rescued with M13KO7 helper phage, recombinant phages displaying ScFv fragments were harvested from the supernatant and selected with endotoxin. The enriched positive clones were reinfected into TG1 cells. Finally, 190 clones were randomly selected to detect the anti endotoxin antibody with indirect ELISA. Results: The titer of anti endotoxin in murine sera was 1:12,800. The concentration of total RNA was 12.38 μg/ml. 1.9×107 clones were obtained after transformed into TG1. 3×104 colonies were gotten after one round panning. Two positive colonies were confirmed with indirect ELISA among 190 randomly selected colonies. Conclusion: A 1.9×107 murine anti endotoxin single chain phage antibody library was successfully constructed. Two anti endotoxin antibodies were obtained from the library.
基金supported by Fondo para la Investigación Cientifica y Tecnológica(FONCy T),Argentina,grant#PICT 2015-2473(to PHHL)supported by grants from National Institute of Health/National Institute of Neurological Disorders and Stroke(NIH/NINDS,USA)(NS121621)+2 种基金Department of Defense,USA(Do D-CL1)(PR200530)partially financed with a fellowship for Research in Medicine from Fundación Florencio Fiorinisupported with a PhD fellowship from CONICET。
文摘Anti-ganglioside antibodies are associated with delayed/poor clinical recovery in Guillain-Barrèsyndrome,mostly related to halted axon regeneration.Cross-linking of cell surface gangliosides by anti-ganglioside antibodies triggers inhibition of nerve repair in in vitro and in vivo paradigms of axon regeneration.These effects involve the activation of the small GTPase Rho A/ROCK signaling pathways,which negatively modulate growth cone cytoskeleton,similarly to well stablished inhibitors of axon regeneration described so far.The aim of this work was to perform a proof of concept study to demonstrate the effectiveness of Y-27632,a selective pharmacological inhibitor of ROCK,in a mouse model of axon regeneration of peripheral nerves,where the passive immunization with a monoclonal antibody targeting gangliosides GD1a and GT1b was previously reported to exert a potent inhibitory effect on regeneration of both myelinated and unmyelinated fibers.Our results demonstrate a differential sensitivity of myelinated and unmyelinated axons to the pro-regenerative effect of Y-27632.Treatment with a total dosage of 9 mg/kg of Y-27632 resulted in a complete prevention of anti-GD1a/GT1b monoclonal antibody-mediated inhibition of axon regeneration of unmyelinated fibers to skin and the functional recovery of mechanical cutaneous sensitivity.In contrast,the same dose showed toxic effects on the regeneration of myelinated fibers.Interestingly,scale down of the dosage of Y-27632 to 5 mg/kg resulted in a significant although not complete recovery of regenerated myelinated axons exposed to anti-GD1a/GT1b monoclonal antibody in the absence of toxicity in animals exposed to only Y-27632.Overall,these findings confirm the in vivo participation of Rho A/ROCK signaling pathways in the molecular mechanisms associated with the inhibition of axon regeneration induced by anti-GD1a/GT1b monoclonal antibody.Our findings open the possibility of therapeutic pharmacological intervention targeting Rho A/Rock pathway in immune neuropathies associated with the presence of anti-ganglioside antibodies and delayed or incomplete clinical recovery after injury in the peripheral nervous system.
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the National Natural Science Foundation of China (No. 30000070)
文摘The cytokine repertoire of ADP/ATP carrier-specific humoral immune responses and the cytokine-dependent anti-ADP/ATP carrier antibody IgG subclasses were examined in a cohort of ADP/ATP carrier-immunized BALB/c mice treated with anti-CD4 monoclonal antibody. Eighteen male BALB/c mice (6–8 weeks old) were randomized into 3 groups: dilated cardiomyopathy (DCM) group, DCM-tolerance (Tol) group and control group. The mice in DCM group were immunized with the peptides derived from human ADP/ATP carrier protein for 6 months and mice in the control group were sham-immunized, while the mice in DCM-Tol group were immunized with ADP/ATP carrier protein and anti-CD4 McAb simultaneously. Serum autoantibody against ADP/ATP carrier and IgG subclasses were measured by ELISA, intracellular cytokines IFN-γ and IL-4 of Th cells were moni- tored with flow cytometry, and splenic T cell cytokines IFN-γ, IL-2, IL-4 and IL-6 were detected by using real-time fluorescent quantitative PCR. The results showed that the autoantibody against ADP/ATP carrier was found in all mice in DCM group, and the antibody level, serum IgG1 and IgG2a subclasses, cytokines in T cells and Th cells were all elevated in DCM group, as compared with those in control group (P〈0.01). On the other hand, in DCM-Tol group, the autoantibody level and contents of all the cytokines were significantly different from those in DCM group (P〈0.01), and were close to those in control group. And the levels of IgG1, IgG2a, IgG2b and IgG3 were influenced, to varying degrees, by anti-CD4 McAb as compared with those in DCM group. All these four types of IgG subclasses were substantially decreased in DCM-Tol group as compared with DCM group. It is concluded that the treatment with anti-CD4 McAb could prevent the activation of T cells, reverse the abnormal secretion of cytokines and the imbalance between Th1/Th2 cell subsets and abnormal production of autoantibody against ADP/ATP carrier, and eventually avoid myocardial injuries.