Anti-thymocyte globulin(ATG)is a pivotal immunosuppressive therapy utilized in the management of T-cell-mediated rejection and steroid-resistant rejection among renal transplant recipients.Commercially available as Th...Anti-thymocyte globulin(ATG)is a pivotal immunosuppressive therapy utilized in the management of T-cell-mediated rejection and steroid-resistant rejection among renal transplant recipients.Commercially available as Thymoglobulin(rabbit-derived,Sanofi,United States),ATG-Fresenius S(rabbit-derived),and ATGAM(equine-derived,Pfizer,United States),these formulations share a common mechanism of action centered on their interaction with cell surface markers of immune cells,imparting immunosuppressive effects.Although the prevailing mechanism predominantly involves T-cell depletion via the complement-mediated pathway,alternate mechanisms have been elucidated.Optimal dosing and treatment duration of ATG have exhibited variance across randomised trials and clinical reports,rendering the establishment of standardized guidelines a challenge.The spectrum of risks associated with ATG administration spans from transient adverse effects such as fever,chills,and skin rash in the acute phase to long-term concerns related to immunosuppression,including susceptibility to infections and malignancies.This comprehensive review aims to provide a thorough exploration of the current understanding of ATG,encompassing its mechanism of action,clinical utility in the treatment of acute renal graft rejections,specifically steroid-resistant cases,efficacy in rejection episode reversal,and a synthesis of findings from different eras of maintenance immunosuppression.Additionally,it delves into the adverse effects associated with ATG therapy and its impact on long-term graft function.Furthermore,the review underscores the existing gaps in evidence,particularly in the context of the Banff classification of rejections,and highlights the challenges faced by clinicians when navigating the available literature to strike the optimal balance between the risks and benefits of ATG utilization in renal transplantation.展开更多
Rabbit anti-thymocyte globulin's manifold mechanisms of action may be attribuited to its polyclonal nature. Its T-cell depleting effect on lymphoid cells is well established: Occurring in the blood and secondary l...Rabbit anti-thymocyte globulin's manifold mechanisms of action may be attribuited to its polyclonal nature. Its T-cell depleting effect on lymphoid cells is well established: Occurring in the blood and secondary lymphoid tissues, depletion proceeds through complement-dependent lysis, opsonization and apoptotic pathways. Clinical studies have shown that rabbit antithymocyte globulin's immunomodulatory effect extends beyond the initial T-cell depletion and up to the period during which lymphocyte populations begin to recover. The drug is able to mediate immunomodulation and graft tolerance by functionally inactivating cell surface receptors involved in antigen recognition, leukocyte trafficking and leukocyte endothelium adhesion. The complex and prolonged immunomodulation induced by this drug contributes to its efficacy in solid organ transplantation, mainly by reducing the incidence of acute graft rejection.展开更多
Children with severe aplastic anemia(SAA)face heterogeneous prognoses after immunosuppressive therapy(IST).There are few models that can predict the long-term outcomes of IST for these patients.The objective of this p...Children with severe aplastic anemia(SAA)face heterogeneous prognoses after immunosuppressive therapy(IST).There are few models that can predict the long-term outcomes of IST for these patients.The objective of this paper is to develop a more effective prediction model for SAA prognosis based on clinical electronic medical records from 203 children with newly diagnosed SAA.In the early stage,a novel model for long-term outcomes of SAA patients with IST was developed using machine-learning techniques.Among the indicators related to long-term efficacy,white blood cell count,lymphocyte count,absolute reticulocyte count,lymphocyte ratio in bone-marrow smears,C-reactive protein,and the level of IL-6,IL-8 and vitamin B12 in the early stage are strongly correlated with long-term efficacy(P<.05).Taken together,we analyzed the long-term outcomes of rabbit antithymocyte globulin and cyclosporine therapy for children with SAA through machine-learning techniques,which may shorten the observation period of therapeutic effects and reduce treatment costs and time.展开更多
Dear Editor,Haploidentical allogeneic hematopoietic stem cell transplantation(haplo-HSCT),a curative therapy for severe aplastic anemia(SAA)patients,has been used clinically for decades.Two models,not involving ex vit...Dear Editor,Haploidentical allogeneic hematopoietic stem cell transplantation(haplo-HSCT),a curative therapy for severe aplastic anemia(SAA)patients,has been used clinically for decades.Two models,not involving ex vitro T-cell depletion,have been adopted for haplo-HSCT in patients with SAA.The first is referred to as the"Beijing protocol"(Xu et al.,2017),and comprises a conditioning regimen using busulfex(BU),cyclophosphamide(CY).展开更多
Chronic graft-versus-host disease(cGVHD)is a major complication following unmanipulated haploidentical hematopoietic stem cell transplantation(haplo-HSCT).We aimed to identify the risk factors for cGVHD in patients wh...Chronic graft-versus-host disease(cGVHD)is a major complication following unmanipulated haploidentical hematopoietic stem cell transplantation(haplo-HSCT).We aimed to identify the risk factors for cGVHD in patients who underwent anti-thymocyte globulin-based haplo-HSCT for acute myeloid leukemia(n=280).The diagnosis of cGVHD was in accordance with the National Institutes of Health consensus criteria.A total of 169 patients suffered from cGVHD.The patients who had 3 loci mismatched had a higher 8-year incidence of cGVHD(total,66.0%vs.53.7%,P=0.031;moderate to severe,42.4%vs.30.1%,P=0.036)than the patients who had 1 to 2 loci mismatched.The patients who had maternal donors had a higher 8-year incidence of moderate to severe cGVHD(49.2%vs.32.9%,P=0.024)compared with the patients who had other donors.The patients who had grades III to IV acute GVHD(aGVHD)had higher 8-year incidence of cGVHD(total,88.0%vs.50.4%,P<0.001;moderate to severe,68.0%vs.27.0%,P<0.001)compared with the patients without aGVHD.In multivariate analysis,grades III to IV aGVHD was the only independent risk factor for cGVHD.Thus,further interventions should be considered in patients with severe aGVHD to prevent cGVHD.展开更多
Hemophagocytic lymphohistiocytosis(HLH) is a hyperinflammatory syndrome that develops as a primary(familial/hereditary) or secondary(non-familial/hereditary) disease characterized in the majority of the cases by hered...Hemophagocytic lymphohistiocytosis(HLH) is a hyperinflammatory syndrome that develops as a primary(familial/hereditary) or secondary(non-familial/hereditary) disease characterized in the majority of the cases by hereditary or acquired impaired cytotoxic T-cell(CTL) and natural killer responses. The molecular mechanisms underlying impaired immune homeostasis have been clarified, particularly for primary diseases. Familial HLH(familial hemophagocytic lymphohistiocytosis type 2-5, Chediak-Higashi syndrome, Griscelli syndrome type 2, Hermansky-Pudlak syndrome type 2) develops due to a defect in lytic granule exocytosis, impairment of(signaling lymphocytic activation molecule)-associated protein, which plays a key role in CTL activity [e.g., X-linked lymphoproliferative syndrome(XLP) 1], or impairment of X-linked inhibitor of apoptosis, a potent regulator of lymphocyte homeostasis(e.g., XLP2). The development of primary HLH is often triggered by infections, but not in all. Secondary HLH develops in association with infection, autoimmune diseases/rheumatological conditions and malignancy. The molecular mechanisms involved in secondary HLH cases remain unknown and the pathophysiology is not the same as primary HLH. For either primary or secondary HLH cases, immunosuppressive therapy should be given to control the hypercytokinemia with steroids, cyclosporine A, or intravenous immune globulin, and if primary HLH is diagnosed, immunochemotherapy with a regimen containing etoposide or anti-thymocyte globulin should be started. Thereafter, allogeneic hematopoietic stem-cell transplantation is recommended for primary HLH or secondary refractory disease(especially EBVHLH).展开更多
Epstein-Barr virus(EBV)reactivation is one of the most important infections after hematopoietic stem cell transplantation(HSCT)using haplo-identical related donors(HID).We aimed to establish a comprehensive model with...Epstein-Barr virus(EBV)reactivation is one of the most important infections after hematopoietic stem cell transplantation(HSCT)using haplo-identical related donors(HID).We aimed to establish a comprehensive model with machine learning,which could predict EBV reactivation after HID HSCT with anti-thymocyte globulin(ATG)for graft-versus-host disease(GVHD)prophylaxis.We enrolled 470 consecutive acute leukemia patients,60%of them(n=282)randomly selected as a training cohort,the remaining 40%(n=188)as a validation cohort.The equation was as follows:Probability(EBV reactivation)=1/1+exp(−Y),where Y=0.0250×(age)–0.3614×(gender)+0.0668×(underlying disease)–0.6297×(disease status before HSCT)–0.0726×(disease risk index)–0.0118×(hematopoietic cell transplantation-specific comorbidity index[HCT-CI]score)+1.2037×(human leukocyte antigen disparity)+0.5347×(EBV serostatus)+0.1605×(conditioning regimen)–0.2270×(donor/recipient gender matched)+0.2304×(donor/recipient relation)–0.0170×(mononuclear cell counts in graft)+0.0395×(CD34+cell count in graft)–2.4510.The threshold of probability was 0.4623,which separated patients into low-and high-risk groups.The 1-year cumulative incidence of EBV reactivation in the low-and high-risk groups was 11.0%versus 24.5%(P<.001),10.7%versus 19.3%(P=.046),and 11.4%versus 31.6%(P=.001),respectively,in total,training and validation cohorts.The model could also predict relapse and survival after HID HSCT.We established a comprehensive model that could predict EBV reactivation in HID HSCT recipients using ATG for GVHD prophylaxis.展开更多
文摘Anti-thymocyte globulin(ATG)is a pivotal immunosuppressive therapy utilized in the management of T-cell-mediated rejection and steroid-resistant rejection among renal transplant recipients.Commercially available as Thymoglobulin(rabbit-derived,Sanofi,United States),ATG-Fresenius S(rabbit-derived),and ATGAM(equine-derived,Pfizer,United States),these formulations share a common mechanism of action centered on their interaction with cell surface markers of immune cells,imparting immunosuppressive effects.Although the prevailing mechanism predominantly involves T-cell depletion via the complement-mediated pathway,alternate mechanisms have been elucidated.Optimal dosing and treatment duration of ATG have exhibited variance across randomised trials and clinical reports,rendering the establishment of standardized guidelines a challenge.The spectrum of risks associated with ATG administration spans from transient adverse effects such as fever,chills,and skin rash in the acute phase to long-term concerns related to immunosuppression,including susceptibility to infections and malignancies.This comprehensive review aims to provide a thorough exploration of the current understanding of ATG,encompassing its mechanism of action,clinical utility in the treatment of acute renal graft rejections,specifically steroid-resistant cases,efficacy in rejection episode reversal,and a synthesis of findings from different eras of maintenance immunosuppression.Additionally,it delves into the adverse effects associated with ATG therapy and its impact on long-term graft function.Furthermore,the review underscores the existing gaps in evidence,particularly in the context of the Banff classification of rejections,and highlights the challenges faced by clinicians when navigating the available literature to strike the optimal balance between the risks and benefits of ATG utilization in renal transplantation.
文摘Rabbit anti-thymocyte globulin's manifold mechanisms of action may be attribuited to its polyclonal nature. Its T-cell depleting effect on lymphoid cells is well established: Occurring in the blood and secondary lymphoid tissues, depletion proceeds through complement-dependent lysis, opsonization and apoptotic pathways. Clinical studies have shown that rabbit antithymocyte globulin's immunomodulatory effect extends beyond the initial T-cell depletion and up to the period during which lymphocyte populations begin to recover. The drug is able to mediate immunomodulation and graft tolerance by functionally inactivating cell surface receptors involved in antigen recognition, leukocyte trafficking and leukocyte endothelium adhesion. The complex and prolonged immunomodulation induced by this drug contributes to its efficacy in solid organ transplantation, mainly by reducing the incidence of acute graft rejection.
基金supported by the CAMS Innovation Fund for Medical Sciences(CIFMS,2021-I2M-C&T-B-082)National Key Research and Development Program of China(2016YFC0901503)the National Natural Science Foundation of China(81500156,81170470).
文摘Children with severe aplastic anemia(SAA)face heterogeneous prognoses after immunosuppressive therapy(IST).There are few models that can predict the long-term outcomes of IST for these patients.The objective of this paper is to develop a more effective prediction model for SAA prognosis based on clinical electronic medical records from 203 children with newly diagnosed SAA.In the early stage,a novel model for long-term outcomes of SAA patients with IST was developed using machine-learning techniques.Among the indicators related to long-term efficacy,white blood cell count,lymphocyte count,absolute reticulocyte count,lymphocyte ratio in bone-marrow smears,C-reactive protein,and the level of IL-6,IL-8 and vitamin B12 in the early stage are strongly correlated with long-term efficacy(P<.05).Taken together,we analyzed the long-term outcomes of rabbit antithymocyte globulin and cyclosporine therapy for children with SAA through machine-learning techniques,which may shorten the observation period of therapeutic effects and reduce treatment costs and time.
文摘Dear Editor,Haploidentical allogeneic hematopoietic stem cell transplantation(haplo-HSCT),a curative therapy for severe aplastic anemia(SAA)patients,has been used clinically for decades.Two models,not involving ex vitro T-cell depletion,have been adopted for haplo-HSCT in patients with SAA.The first is referred to as the"Beijing protocol"(Xu et al.,2017),and comprises a conditioning regimen using busulfex(BU),cyclophosphamide(CY).
文摘Chronic graft-versus-host disease(cGVHD)is a major complication following unmanipulated haploidentical hematopoietic stem cell transplantation(haplo-HSCT).We aimed to identify the risk factors for cGVHD in patients who underwent anti-thymocyte globulin-based haplo-HSCT for acute myeloid leukemia(n=280).The diagnosis of cGVHD was in accordance with the National Institutes of Health consensus criteria.A total of 169 patients suffered from cGVHD.The patients who had 3 loci mismatched had a higher 8-year incidence of cGVHD(total,66.0%vs.53.7%,P=0.031;moderate to severe,42.4%vs.30.1%,P=0.036)than the patients who had 1 to 2 loci mismatched.The patients who had maternal donors had a higher 8-year incidence of moderate to severe cGVHD(49.2%vs.32.9%,P=0.024)compared with the patients who had other donors.The patients who had grades III to IV acute GVHD(aGVHD)had higher 8-year incidence of cGVHD(total,88.0%vs.50.4%,P<0.001;moderate to severe,68.0%vs.27.0%,P<0.001)compared with the patients without aGVHD.In multivariate analysis,grades III to IV aGVHD was the only independent risk factor for cGVHD.Thus,further interventions should be considered in patients with severe aGVHD to prevent cGVHD.
文摘Hemophagocytic lymphohistiocytosis(HLH) is a hyperinflammatory syndrome that develops as a primary(familial/hereditary) or secondary(non-familial/hereditary) disease characterized in the majority of the cases by hereditary or acquired impaired cytotoxic T-cell(CTL) and natural killer responses. The molecular mechanisms underlying impaired immune homeostasis have been clarified, particularly for primary diseases. Familial HLH(familial hemophagocytic lymphohistiocytosis type 2-5, Chediak-Higashi syndrome, Griscelli syndrome type 2, Hermansky-Pudlak syndrome type 2) develops due to a defect in lytic granule exocytosis, impairment of(signaling lymphocytic activation molecule)-associated protein, which plays a key role in CTL activity [e.g., X-linked lymphoproliferative syndrome(XLP) 1], or impairment of X-linked inhibitor of apoptosis, a potent regulator of lymphocyte homeostasis(e.g., XLP2). The development of primary HLH is often triggered by infections, but not in all. Secondary HLH develops in association with infection, autoimmune diseases/rheumatological conditions and malignancy. The molecular mechanisms involved in secondary HLH cases remain unknown and the pathophysiology is not the same as primary HLH. For either primary or secondary HLH cases, immunosuppressive therapy should be given to control the hypercytokinemia with steroids, cyclosporine A, or intravenous immune globulin, and if primary HLH is diagnosed, immunochemotherapy with a regimen containing etoposide or anti-thymocyte globulin should be started. Thereafter, allogeneic hematopoietic stem-cell transplantation is recommended for primary HLH or secondary refractory disease(especially EBVHLH).
基金the Program of the National Natural Science Foundation of China(grant number 82170208)the Foundation for Innovative Research Groups of the National Natural Science Foundation of China(grant number 81621001)+2 种基金the CAMS Innovation Fund for Medical Sciences(CIFMS)(grant number 2019-I2M-5-034)the Key Program of the National Natural Science Foundation of China(grant number 81930004)the Fundamental Research Funds for the Central Universities,National Natural Science Foundation of China(No.62102008).
文摘Epstein-Barr virus(EBV)reactivation is one of the most important infections after hematopoietic stem cell transplantation(HSCT)using haplo-identical related donors(HID).We aimed to establish a comprehensive model with machine learning,which could predict EBV reactivation after HID HSCT with anti-thymocyte globulin(ATG)for graft-versus-host disease(GVHD)prophylaxis.We enrolled 470 consecutive acute leukemia patients,60%of them(n=282)randomly selected as a training cohort,the remaining 40%(n=188)as a validation cohort.The equation was as follows:Probability(EBV reactivation)=1/1+exp(−Y),where Y=0.0250×(age)–0.3614×(gender)+0.0668×(underlying disease)–0.6297×(disease status before HSCT)–0.0726×(disease risk index)–0.0118×(hematopoietic cell transplantation-specific comorbidity index[HCT-CI]score)+1.2037×(human leukocyte antigen disparity)+0.5347×(EBV serostatus)+0.1605×(conditioning regimen)–0.2270×(donor/recipient gender matched)+0.2304×(donor/recipient relation)–0.0170×(mononuclear cell counts in graft)+0.0395×(CD34+cell count in graft)–2.4510.The threshold of probability was 0.4623,which separated patients into low-and high-risk groups.The 1-year cumulative incidence of EBV reactivation in the low-and high-risk groups was 11.0%versus 24.5%(P<.001),10.7%versus 19.3%(P=.046),and 11.4%versus 31.6%(P=.001),respectively,in total,training and validation cohorts.The model could also predict relapse and survival after HID HSCT.We established a comprehensive model that could predict EBV reactivation in HID HSCT recipients using ATG for GVHD prophylaxis.
