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Transplantation Reviews (Orlando, Fla.) Jul 2017Compelling data suggest that lymphocyte depletion following T cell depleting therapy may induce prolonged CD4 T cell lymphopenia and trigger lymphocyte activation in... (Review)
Review
Compelling data suggest that lymphocyte depletion following T cell depleting therapy may induce prolonged CD4 T cell lymphopenia and trigger lymphocyte activation in some patients. These profound and non-reversible immune changes in T cell pool subsets are the consequence of both impaired thymic renewal and peripheral homeostatic proliferation. Chronic viral challenges by CMV play a major role in these immune alterations. Even when the consequences of CD4 T cell lymphopenia have been now well described, recent studies shed new light on the clinical consequences of immune activation. In this review, we will first focus on the mechanisms involved in T cell pool reconstitution after T cell depletion and further consider the clinical consequences of ATG-induced T cell activation and senescence in renal transplant recipients.
Topics: Antilymphocyte Serum; Humans; Kidney Transplantation; Lymphocyte Activation; Lymphocyte Depletion; T-Lymphocytes; Transplantation Immunology
PubMed: 28456447
DOI: 10.1016/j.trre.2017.02.004 -
The Cochrane Database of Systematic... Jun 2023Allogeneic haematopoietic stem cell transplantation (SCT) is an established treatment for many malignant and non-malignant haematological disorders. Graft-versus-host... (Review)
Review
BACKGROUND
Allogeneic haematopoietic stem cell transplantation (SCT) is an established treatment for many malignant and non-malignant haematological disorders. Graft-versus-host disease (GVHD), a condition frequently occurring after an allogeneic SCT, is the result of host tissues being attacked by donor immune cells. It affects more than half of the patients after transplant either as acute and or chronic GVHD. One strategy for the prevention of GVHD is the administration of anti-thymocyte globulins (ATGs), a set of polyclonal antibodies directed against a variety of immune cell epitopes, leading to immunosuppression and immunomodulation.
OBJECTIVES
To assess the effect of ATG used for the prevention of GVHD in patients undergoing allogeneic SCT with regard to overall survival, incidence and severity of acute and chronic GVHD, incidence of relapse, non-relapse mortality, graft failure and adverse events.
SEARCH METHODS
For this update we searched the CENTRAL, MEDLINE, Embase, trial registers and conference proceedings on the 18th November 2022 along with reference checking and contacting study authors to identify additional studies. We did not apply language restrictions.
SELECTION CRITERIA
We included randomised controlled trials (RCTs) investigating the impact of ATG on GVHD prophylaxis in adults suffering from haematological diseases and undergoing allogeneic SCT. The selection criteria were modified from the previous version of this review. Paediatric studies and studies where patients aged < 18 years constituted more than 20 % of the total number were excluded. Treatment arms had to differ only in the addition of ATG to the standard GVHD prophylaxis regimen.
DATA COLLECTION AND ANALYSIS
We used standard methodological procedures expected by the Cochrane Collaboration for data collection, extraction and analyses.
MAIN RESULTS
For this update we included seven new RCTs, leading to a total of ten studies investigating 1413 participants. All patients had a haematological condition which warranted an allogeneic SCT. The risk of bias was estimated as low for seven and unclear for three studies. ATG probably has little or no influence on overall survival (HR (hazard ratio) 0.93 (95 % confidence interval (CI) 0.77 to 1.13, nine studies, n = 1249, moderate-certainty evidence)). Estimated absolute effect: 430 surviving people per 1000 people not receiving ATG compared to 456 people surviving per 1000 people receiving the intervention (95 % CI 385 to 522 per 1000 people). ATG results in a reduction in acute GVHD II to IV with relative risk (RR) 0.68 (95 % CI 0.60 to 0.79, 10 studies, n = 1413, high-certainty evidence). Estimated absolute effect: 418 acute GVHD II to IV per 1000 people not receiving ATG compared to 285 per 1000 people receiving the intervention (95 % CI 251 to 331 per 1000 people). Addition of ATG results in a reduction of overall chronic GvHD with a RR of 0.53 (95 % CI 0.45 to 0.61, eight studies, n = 1273, high-certainty evidence). Estimated absolute effect: 506 chronic GVHD per 1000 people not receiving ATG compared to 268 per 1000 people receiving the intervention (95 % CI 228 to 369 per 1000 people). Further data on severe acute GVHD and extensive chronic GVHD are available in the manuscript. ATG probably slightly increases the incidence of relapse with a RR of 1.21 (95 % CI 0.99 to 1.49, eight studies, n =1315, moderate-certainty evidence). Non relapse mortality is probably slightly or not affected by ATG with an HR of 0.86 (95 % CI 0.67 to 1.11, nine studies, n=1370, moderate-certainty evidence). ATG prophylaxis may result in no increase in graft failure with a RR of 1.55 (95 % CI 0.54 to 4.44, eight studies, n = 1240, low-certainty evidence). Adverse events could not be analysed due to the serious heterogeneity in the reporting between the studies, which limited comparability (moderate-certainty evidence) and are reported in a descriptive manner. Subgroup analyses on ATG types, doses and donor type are available in the manuscript.
AUTHORS' CONCLUSIONS
This systematic review suggests that the addition of ATG during allogeneic SCT probably has little or no influence on overall survival. ATG results in a reduction in the incidence and severity of acute and chronic GvHD. ATG intervention probably slightly increases the incidence of relapse and probably does not affect the non relapse mortality. Graft failure may not be affected by ATG prophylaxis. Analysis of data on adverse events was reported in a narrative manner. A limitation for the analysis was the imprecision in reporting between the studies thereby reducing the confidence in the certainty of evidence.
Topics: Adult; Humans; Child; Bone Marrow Transplantation; Antilymphocyte Serum; Graft vs Host Disease; Hematopoietic Stem Cell Transplantation; Bronchiolitis Obliterans Syndrome
PubMed: 37341189
DOI: 10.1002/14651858.CD009159.pub3 -
Blood Sep 2019
Topics: Antilymphocyte Serum; Cyclophosphamide; Graft vs Host Disease; Humans; Unrelated Donors
PubMed: 31515227
DOI: 10.1182/blood.2019002284 -
Transplantation Sep 2019Limited published data exist to guide the treatment of pancreas transplant rejection.
BACKGROUND
Limited published data exist to guide the treatment of pancreas transplant rejection.
METHODS
We reviewed the treatment and outcomes of 158 first episodes of biopsy-proven pancreas rejection between 1 January 1997 and 31 December 2016. Within each Banff grade of rejection, we compared response rates and long-term outcomes with steroids alone versus steroids plus antithymocyte globulin (ATG).
RESULTS
Of 158 pancreas recipients with rejection, 65 were treated with steroids alone. Eighty-three percent of patients with grade I, 60% with grade II, and 33.33% with grade III rejection responded to treatment with steroids alone. Ninety-three patients were treated with steroids plus ATG. The response rates were 69% in grade I, 76% in grade II, and 73% in grade III. Response rates and graft survival were not different with grade I rejection treated with steroids alone versus steroids plus ATG. However, response rates and graft survival were significantly better with grade III rejection treated with the addition of ATG, and graft survival rates were significantly better with grade II rejection treated with the addition of ATG.
CONCLUSIONS
Grade I pancreas rejection can usually be successfully treated with steroids alone, whereas grade II and III rejection should usually be treated with steroids plus ATG, as the addition of ATG improves both response rates and graft survival.
Topics: Adult; Antilymphocyte Serum; Drug Therapy, Combination; Female; Graft Rejection; Graft Survival; Humans; Immunocompromised Host; Immunosuppressive Agents; Male; Middle Aged; Opportunistic Infections; Pancreas Transplantation; Plasma Exchange; Risk Factors; Severity of Illness Index; Steroids; Time Factors; Treatment Outcome
PubMed: 31233481
DOI: 10.1097/TP.0000000000002694 -
Blood Advances Feb 2022Traditional weight-based dosing results in variable rabbit antithymocyte globulin (rATG) clearance that can delay CD4+ T-cell immune reconstitution (CD4+ IR) leading to...
Traditional weight-based dosing results in variable rabbit antithymocyte globulin (rATG) clearance that can delay CD4+ T-cell immune reconstitution (CD4+ IR) leading to higher mortality. In a retrospective pharmacokinetic/pharmacodynamic (PK/PD) analysis of patients undergoing their first CD34+ T-cell-depleted (TCD) allogeneic hematopoietic cell transplantation (HCT) after myeloablative conditioning with rATG, we estimated post-HCT rATG exposure as area under the curve (arbitrary unit per day/milliliter [AU × day/mL]) using a validated population PK model. We related rATG exposure to nonrelapse mortality (NRM), CD4+ IR (CD4+ ≥50 cells per µL at 2 consecutive measures within 100 days after HCT), overall survival, relapse, and acute graft-versus-host disease (aGVHD) to define an optimal rATG exposure. We used Cox proportional hazard models and multistate competing risk models for analysis. In all, 554 patients were included (age range, 0.1-73 years). Median post-HCT rATG exposure was 47 AU × day/mL (range, 0-101 AU × day/mL). Low post-HCT area under the curve (<30 AU × day/mL) was associated with lower risk of NRM (P < .01) and higher probability of achieving CD4+ IR (P < .001). Patients who attained CD4+ IR had a sevenfold lower 5-year NRM (P < .0001). The probability of achieving CD4+ IR was 2.5-fold higher in the <30 AU × day/mL group compared with 30-55 AU × day/mL and threefold higher in the <30 AU × day/mL group compared with the ≥55 AU × day/mL group. In multivariable analyses, post-HCT rATG exposure ≥55 AU × day/mL was associated with an increased risk of NRM (hazard ratio, 3.42; 95% confidence interval, 1.26-9.30). In the malignancy subgroup (n = 515), a tenfold increased NRM was observed in the ≥55 AU × day/mL group, and a sevenfold increased NRM was observed in the 30-55 AU × day/mL group compared with the <30 AU × day/mL group. Post-HCT rATG exposure ≥55 AU × day/mL was associated with higher risk of a GVHD (hazard ratio, 2.28; 95% confidence interval, 1.01-5.16). High post-HCT rATG exposure is associated with higher NRM secondary to poor CD4+ IR after TCD HCT. Using personalized PK-directed rATG dosing to achieve optimal exposure may improve survival after HCT.
Topics: Antigens, CD34; Antilymphocyte Serum; Hematopoietic Stem Cell Transplantation; Humans; Neoplasm Recurrence, Local; Retrospective Studies; T-Lymphocytes
PubMed: 34788361
DOI: 10.1182/bloodadvances.2021005584 -
Transplantation Reviews (Orlando, Fla.) Apr 2016The mode of action of rabbit antithymocyte globulin (rATG) includes preferential inhibition of pre-existing donor-reactive memory T-cell reconstitution and possibly... (Review)
Review
The mode of action of rabbit antithymocyte globulin (rATG) includes preferential inhibition of pre-existing donor-reactive memory T-cell reconstitution and possibly apoptosis of plasma cells, the source of donor specific antibodies (DSAs). In kidney transplant patients with low-strength preformed DSAs, non-comparative data have shown a low incidence of antibody-mediated rejection (ABMR) and graft survival using rATG even without desensitization procedures. For high strengths of preformed DSAs, rATG induction with more aggressive desensitization appears effective, with mixed results concerning the addition of B-cell specific agents. Regarding production of de novo DSA (dnDSA), interpretation of retrospective analyses is limited by selective use of rATG in higher-risk patients. Observational data in moderately sensitized kidney transplant patients suggest that the incidence of dnDSA and ABMR is significantly lower with rATG versus basiliximab. A randomized pilot study has suggested that addition of rituximab or bortezomib may not further inhibit dnDSA production in rATG-treated patients. Overall, rATG appears to inhibit DSA production, with a potential role in reducing the risk of ABMR in kidney transplant patients with high-strength preformed DSA, or lowering dnDSA in moderately sensitized patients. Randomized trials are awaited.
Topics: Animals; Antibodies; Antilymphocyte Serum; Graft Rejection; Graft Survival; Immunologic Factors; Kidney Transplantation; Rabbits; Tissue Donors
PubMed: 26951711
DOI: 10.1016/j.trre.2015.12.002 -
Diabetes Care Feb 2024Low-dose antithymocyte globulin (ATG) (2.5 mg/kg) preserves C-peptide and reduces HbA1c in new-onset stage 3 type 1 diabetes, yet efficacy in delaying progression from...
OBJECTIVE
Low-dose antithymocyte globulin (ATG) (2.5 mg/kg) preserves C-peptide and reduces HbA1c in new-onset stage 3 type 1 diabetes, yet efficacy in delaying progression from stage 2 to stage 3 has not been evaluated.
RESEARCH DESIGN AND METHODS
Children (n = 6) aged 5-14 years with stage 2 type 1 diabetes received off-label, low-dose ATG. HbA1c, C-peptide, continuous glucose monitoring, insulin requirements, and side effects were followed for 18-48 months.
RESULTS
Three subjects (50%) remained diabetes free after 1.5, 3, and 4 years of follow-up, while three developed stage 3 within 1-2 months after therapy. Eighteen months posttreatment, even disease progressors demonstrated near-normal HbA1c (5.1% [32 mmol/mol], 5.6% [38 mmol/mol], and 5.3% [34 mmol/mol]), time in range (93%, 88%, and 98%), low insulin requirements (0.17, 0.18, and 0.34 units/kg/day), and robust C-peptide 90 min after mixed meal (1.3 ng/dL, 2.3 ng/dL, and 1.4 ng/dL).
CONCLUSIONS
These observations support additional prospective studies evaluating ATG in stage 2 type 1 diabetes.
Topics: Child; Humans; Antilymphocyte Serum; Blood Glucose; Blood Glucose Self-Monitoring; C-Peptide; Diabetes Mellitus, Type 1; Glycated Hemoglobin; Hypoglycemic Agents; Insulin; Prospective Studies
PubMed: 38117469
DOI: 10.2337/dc23-1750 -
Leukemia & Lymphoma Aug 2017The efficacy of rabbit antithymocyte globulin (ATG) for the prevention of graft-versus-host disease (GVHD) has been evaluated in several randomized control trials, but... (Meta-Analysis)
Meta-Analysis Review
The efficacy of rabbit antithymocyte globulin (ATG) for the prevention of graft-versus-host disease (GVHD) has been evaluated in several randomized control trials, but the results show some discrepancies. Therefore, we performed a systematic review and meta-analysis covering the latest RCTs including six trials (total 845 patients). The incidence of acute and chronic GVHD was significantly lower in the ATG arms (risk ratio, 0.75 and 0.54, respectively). No significant differences were found regarding overall survival, the incidence of relapse, and non-relapse mortality; however, the incidence of cytomegalovirus and Epstein-Barr virus reactivation increased (risk ratio, 1.25 and 1.33), and neutrophil engraftment was significantly delayed (median, 2.66 days). In conclusion, rabbit ATG should be beneficial as a GVHD prophylaxis in addition to conventional regimens, with close monitoring of virus reactivation and enough attention to delayed engraftment. Studies comparing the timing and dosage of ATG are essential to determine the suitable prophylactic regimens.
Topics: Acute Disease; Antilymphocyte Serum; Chronic Disease; Graft Survival; Graft vs Host Disease; Hematopoietic Stem Cell Transplantation; Humans; Immunologic Factors; Incidence; Mortality; Odds Ratio; Proportional Hazards Models; Quality of Life; Transplantation, Homologous; Treatment Outcome
PubMed: 27951736
DOI: 10.1080/10428194.2016.1266624 -
Transplantation Reviews (Orlando, Fla.) Jul 2018Changes in recipient and donor characteristics are redefining the role of induction in liver transplant recipients. Older recipients are more common, with greater... (Review)
Review
Changes in recipient and donor characteristics are redefining the role of induction in liver transplant recipients. Older recipients are more common, with greater concomitant comorbidity. Moderate or severe renal dysfunction is now estimated to affect 40% of liver transplant recipients. Donors are also becoming older, and other factors such as more frequent non-alcoholic fatty liver disease (NAFLD) compromise the quality of some grafts. Rejection rates are now relatively low (~10%) but some patients have a markedly increased risk such as younger recipients and those undergoing re-transplantation. Induction immunosuppression is associated with a significant reduction in rejection risk but due to various factors universal induction is not justified. Steroid-free therapy without induction increases the risk of biopsy-proven acute rejection (BPAR) but randomized trials have shown that induction with an interleukin-2 antagonist receptor (IL-2RA) agent or with rabbit antithymocyte globulin (rATG) maintains immunosuppressive efficacy in steroid-free regimens. Delayed calcineurin inhibitor (CNI) initiation (e.g. to days 4-5 post-transplant) can prevent deterioration of renal function during the first year post-transplant, but requires induction with an IL-2RA agent or rATG to maintain early immunosuppressive efficacy. IL-2RA induction may be inadequate to ensure a low risk of rejection in a steroid-free regimen combined with delayed tacrolimus. Randomized trials of CNI withdrawal at month 1 post-transplant have only achieved an acceptable rate of BPAR when induction is administered. In terms of safety, an increased rate of infection does not seem to be a concern. The most recent large-scale analyses have not indicated any evidence for an increased risk of malignancy, or specifically post-transplant lymphoproliferative disease. In summary, the place of induction in the management of liver transplant patients is becoming established. Selective use in high-risk individuals to avoid graft rejection is still relevant, but the key rationale for induction is to facilitate steroid-sparing and CNI-sparing regimens to reduce long-term complications.
Topics: Antilymphocyte Serum; Basiliximab; Donor Selection; Graft Rejection; Humans; Immunosuppression Therapy; Immunosuppressive Agents; Liver Transplantation; Risk Factors
PubMed: 29709248
DOI: 10.1016/j.trre.2018.04.001 -
Jornal Brasileiro de Nefrologia 2015The combination of immunosuppressive drugs is part of the treatment regimen of patients undergoing kidney transplantation (RT). Thymoglobulin®, a rabbit immunoglobulin... (Review)
Review
The combination of immunosuppressive drugs is part of the treatment regimen of patients undergoing kidney transplantation (RT). Thymoglobulin®, a rabbit immunoglobulin directed against human thymocytes, is the most commonly agent used for induction therapy in RT in the US. In Brazil, Thymoglobulin® is approved by ANVISA for the use in patients who underwent kidney transplantation and despite being widely used, there are controversies regarding the drug administration. We prepared a systematic review of the literature, evaluating studies that used Thymoglobulin® for induction and for acute rejection treatment in patients undergoing RT. The review used the computadorized databases of EMBASE, LILACS and MedLine. Data were extracted from the studies concerning general features, methodological characteristics and variables analyzed in each study. From the results, a practical guide was prepared analyzing various aspects on the use of Thymoglobulin® in patients submitted to RT.
Topics: Antilymphocyte Serum; Graft Rejection; Humans; Immunosuppressive Agents; Kidney Transplantation; Practice Guidelines as Topic
PubMed: 26154644
DOI: 10.5935/0101-2800.20150036