BACKGROUND Donor-specific antibodies(DSAs)against human leukocyte antigen(HLA)-DQ are increasingly recognized as major contributors to antibody-mediated rejection(AMR)and graft failure in kidney transplantation.Howeve...BACKGROUND Donor-specific antibodies(DSAs)against human leukocyte antigen(HLA)-DQ are increasingly recognized as major contributors to antibody-mediated rejection(AMR)and graft failure in kidney transplantation.However,their clinical impact remains understudied in Morocco.AIM To evaluate the presence and implications of anti-HLA-DQ DSAs in Moroccan kidney transplant recipients.METHODS We retrospectively analyzed the immunological profiles and clinical outcomes of kidney transplant recipients screened for anti-HLA antibodies between 2015 and 2020,who developed anti-HLA-DQ DSAs either before or after transplantation.Anti-HLA antibodies were identified using Luminex®single antigen bead technology,and clinical follow-up included graft function assessment,biopsy interpretation,and evaluation of immunosuppression.RESULTS In the pre-transplant group(n=6 with confirmed donor typing),patients with low to moderate median fluorescence intensity(MFI)anti-HLA-DQ DSAs(MFI 561-1581)underwent successful transplantation and maintained stable graft function under optimized immunosuppression.In contrast,in the post-transplant group(n=6 with confirmed donor typing),the emergence of de novo anti-HLA-DQ DSAs was consistently associated with AMR,with MFI values reaching up to 19473,with biopsy-proven AMR in 5 of 6 cases and suspicion of AMR in 1 case.Two representative cases are detailed to illustrate the clinical impact of DQ DSAs:one patient developed high-level anti-DQB1*02 de novo DSA(MFI 12029)with persistent AMR after 5 years,while another developed anti-DQA1*05:01 de novo DSA after an early AMR episode but maintained stable graft function after 5 years(creatinine 1.48 mg/dL).CONCLUSION Our findings underscore the clinical significance of anti-HLA-DQ DSAs in Moroccan kidney transplant recipients.While preformed DSAs with low immunogenicity may permit successful transplantation,de novo DSAs strongly correlate with AMR.Proactive monitoring,including routine DSA screening and HLA-DQ typing,could improve graft outcomes by enabling early intervention and better donor selection.展开更多
Donor human leukocyte antigen(HLA)-specific antibodies(DSA) play an important role in solid organ transplantation. Preexisting IgG isotype DSA are considered a risk factor for antibody mediated rejection, graft failur...Donor human leukocyte antigen(HLA)-specific antibodies(DSA) play an important role in solid organ transplantation. Preexisting IgG isotype DSA are considered a risk factor for antibody mediated rejection, graft failure or graft loss. The post-transplant development of DSA depends on multiple factors including immunogenicity of mismatched antigens, HLA class Ⅱ typing of the recipient, cytokine gene polymorphisms, and cellular immunoregulatory mechanisms. De novo developed antibodies require special attention because not all DSA have equal clinical significance. Therefore, it is important for transplant clinicians and transplant immunologists to accurately characterize DSA. In this review, the contemporary immunological techniques for detection and characterization of anti-HLA antibodies and their pitfalls are described.展开更多
Human leukocyte antigen(HLA)compatibility is very important for successful transplantation of solid organs.In this paper,we focused on the humoral arm of immunity in the clinical setting of organ transplantation:how H...Human leukocyte antigen(HLA)compatibility is very important for successful transplantation of solid organs.In this paper,we focused on the humoral arm of immunity in the clinical setting of organ transplantation:how HLA antibodies develop,how they can be detected,and what they can do to injure organ transplants.Specifically,we explore the technical perspectives of detecting donor-specific antibodies(DSA)in HLA laboratories,and use real-life clinical cases to explain the principles.Currently there are many tools in our HLA antibody detection toolbox:conventional cytotoxicity cross match,flow cross match,and solid phase assays using beads conjugated with single or multiple HLA antigens.Single antigen bead(SAB)assay is the most sensitive tool available for detecting HLA antibodies and assessing the immunological risk for organ transplant.However,there are intrinsic limitations to solid-phase assays and they are prone to both false negativity and importantly,false positivity.Denatured antigens on single antigen beads might be the most prominent source of false positive reactivity,and may have been underestimated by many HLA experts.No single assay is perfect and therefore multiple methods,including the less sensitive assays,should be employed to determine the clinical relevance of detected HLA antibodies.Thoughtful process,including knowledge of HLA systems,cross reactivity,epitopes,and the patient's clinical history should be employed to correctly interpret data.The clinical team should work closely with HLA laboratories to ensure accurate interpretation of information and optimal management of patients before and after organ transplantation.展开更多
基金Supported by the National Science and Technology Research Center(Morocco)“PhD-Associate Scholarship-PASS”Program,No.88UH2C2023.
文摘BACKGROUND Donor-specific antibodies(DSAs)against human leukocyte antigen(HLA)-DQ are increasingly recognized as major contributors to antibody-mediated rejection(AMR)and graft failure in kidney transplantation.However,their clinical impact remains understudied in Morocco.AIM To evaluate the presence and implications of anti-HLA-DQ DSAs in Moroccan kidney transplant recipients.METHODS We retrospectively analyzed the immunological profiles and clinical outcomes of kidney transplant recipients screened for anti-HLA antibodies between 2015 and 2020,who developed anti-HLA-DQ DSAs either before or after transplantation.Anti-HLA antibodies were identified using Luminex®single antigen bead technology,and clinical follow-up included graft function assessment,biopsy interpretation,and evaluation of immunosuppression.RESULTS In the pre-transplant group(n=6 with confirmed donor typing),patients with low to moderate median fluorescence intensity(MFI)anti-HLA-DQ DSAs(MFI 561-1581)underwent successful transplantation and maintained stable graft function under optimized immunosuppression.In contrast,in the post-transplant group(n=6 with confirmed donor typing),the emergence of de novo anti-HLA-DQ DSAs was consistently associated with AMR,with MFI values reaching up to 19473,with biopsy-proven AMR in 5 of 6 cases and suspicion of AMR in 1 case.Two representative cases are detailed to illustrate the clinical impact of DQ DSAs:one patient developed high-level anti-DQB1*02 de novo DSA(MFI 12029)with persistent AMR after 5 years,while another developed anti-DQA1*05:01 de novo DSA after an early AMR episode but maintained stable graft function after 5 years(creatinine 1.48 mg/dL).CONCLUSION Our findings underscore the clinical significance of anti-HLA-DQ DSAs in Moroccan kidney transplant recipients.While preformed DSAs with low immunogenicity may permit successful transplantation,de novo DSAs strongly correlate with AMR.Proactive monitoring,including routine DSA screening and HLA-DQ typing,could improve graft outcomes by enabling early intervention and better donor selection.
文摘Donor human leukocyte antigen(HLA)-specific antibodies(DSA) play an important role in solid organ transplantation. Preexisting IgG isotype DSA are considered a risk factor for antibody mediated rejection, graft failure or graft loss. The post-transplant development of DSA depends on multiple factors including immunogenicity of mismatched antigens, HLA class Ⅱ typing of the recipient, cytokine gene polymorphisms, and cellular immunoregulatory mechanisms. De novo developed antibodies require special attention because not all DSA have equal clinical significance. Therefore, it is important for transplant clinicians and transplant immunologists to accurately characterize DSA. In this review, the contemporary immunological techniques for detection and characterization of anti-HLA antibodies and their pitfalls are described.
文摘Human leukocyte antigen(HLA)compatibility is very important for successful transplantation of solid organs.In this paper,we focused on the humoral arm of immunity in the clinical setting of organ transplantation:how HLA antibodies develop,how they can be detected,and what they can do to injure organ transplants.Specifically,we explore the technical perspectives of detecting donor-specific antibodies(DSA)in HLA laboratories,and use real-life clinical cases to explain the principles.Currently there are many tools in our HLA antibody detection toolbox:conventional cytotoxicity cross match,flow cross match,and solid phase assays using beads conjugated with single or multiple HLA antigens.Single antigen bead(SAB)assay is the most sensitive tool available for detecting HLA antibodies and assessing the immunological risk for organ transplant.However,there are intrinsic limitations to solid-phase assays and they are prone to both false negativity and importantly,false positivity.Denatured antigens on single antigen beads might be the most prominent source of false positive reactivity,and may have been underestimated by many HLA experts.No single assay is perfect and therefore multiple methods,including the less sensitive assays,should be employed to determine the clinical relevance of detected HLA antibodies.Thoughtful process,including knowledge of HLA systems,cross reactivity,epitopes,and the patient's clinical history should be employed to correctly interpret data.The clinical team should work closely with HLA laboratories to ensure accurate interpretation of information and optimal management of patients before and after organ transplantation.
