In kidney transplantation, survival rates are still partly impaired due to the deleterious effects of donor specific HLA antibodies (DSA). However, not all luminex-defined DSA appear to be... Show moreIn kidney transplantation, survival rates are still partly impaired due to the deleterious effects of donor specific HLA antibodies (DSA). However, not all luminex-defined DSA appear to be clinically relevant. Further analysis of DSA recognizing polymorphic amino acid configurations, called eplets or functional epitopes, might improve the discrimination between clinically relevant vs. irrelevant HLA antibodies. To evaluate which donor epitope-specific HLA antibodies (DESAs) are clinically important in kidney graft survival, relevant and irrelevant DESAs were discerned in a Dutch cohort of 4690 patients using Kaplan-Meier analysis and tested in a cox proportional hazard (CPH) model including nonimmunological variables. Pre-transplant DESAs were detected in 439 patients (9.4%). The presence of certain clinically relevant DESAs was significantly associated with increased risk on graft loss in deceased donor transplantations (p < 0.0001). The antibodies recognized six epitopes of HLA Class I, 3 of HLA-DR, and 1 of HLA-DQ, and most antibodies were directed to HLA-B (47%). Fifty-three patients (69.7%) had DESA against one donor epitope (range 1-5). Long-term graft survival rate in patients with clinically relevant DESA was 32%, rendering DESA a superior parameter to classical DSA (60%). In the CPH model, the hazard ratio (95% CI) of clinically relevant DESAs was 2.45 (1.84-3.25) in deceased donation, and 2.22 (1.25-3.95) in living donation. In conclusion, the developed model shows the deleterious effect of clinically relevant DESAs on graft outcome which outperformed traditional DSA-based risk analysis on antigen level. Show less
In kidney transplantation, donor HLA antibodies are a risk factor for graft loss. Accessibility of donor eplets for HLA antibodies is predicted by the ElliPro score. The clinical usefulness of... Show moreIn kidney transplantation, donor HLA antibodies are a risk factor for graft loss. Accessibility of donor eplets for HLA antibodies is predicted by the ElliPro score. The clinical usefulness of those scores in relation to transplant outcome is unknown. In a large Dutch kidney transplant cohort, Ellipro scores of pretransplant donor antibodies that can be assigned to known eplets (donor epitope specific HLA antibodies [DESAs]) were compared between early graft failure and long surviving deceased donor transplants. We did not observe a significant Ellipro score difference between the two cohorts, nor significant differences in graft survival between transplants with DESAs having high versus low total Ellipro scores. We conclude that Ellipro scores cannot be used to identify DESAs associated with early versus late kidney graft loss in deceased donor transplants. Show less
Biewenga, M.; Verhelst, X.; Baven-Pronk, M.; Putter, H.; Berg, A. van den; Colle, I.; ... ; Dutch Autoimmune Hepatitis Study Group 2022
BACKGROUND & AIMS: Biochemical remission, important treatment goal in autoimmune hepatitis (AIH), has been associated with better long-term survival. The aim of this study was to determine the... Show moreBACKGROUND & AIMS: Biochemical remission, important treatment goal in autoimmune hepatitis (AIH), has been associated with better long-term survival. The aim of this study was to determine the independent prognostic value of aminotransferases and immunoglobulin G (IgG) during treatment on long-term transplant-free survival in AIH. METHODS: In a multicenter cohort alanine aminotransferase, aspartate aminotransferase (AST), and IgG were collected at diagnosis and 6, 12, 24, and 36 months after start of therapy and related to long-term outcome using Kaplan-Meier survival and Cox regression analysis with landmark analysis at these time points, excluding patients with follow-up ending before each landmark. RESULTS: A total of 301 AIH patients with a median follow-up of 99 (range, 7-438) months were included. During follow-up, 15 patients required liver transplantation and 33 patients died. Higher AST at 12 months was associated with worse survival (hazard ratio [HR], 1.86; P <.001), while IgG was not associated with survival (HR, 1.30; P =.53). In multivariate analysis AST at 12 months (HR, 2.13; P <.001) was predictive for survival independent of age, AST at diagnosis and cirrhosis. Multivariate analysis for AST yielded similar results at 6 months (HR, 2.61; P =.001), 24 months (HR, 2.93; P =.003), and 36 months (HR, 3.03; P =.010). There was a trend toward a worse survival in patients with mildly elevated aminotransferases (1-1.53 upper limit of normal) compared with patients with normal aminotransferases (P =.097). CONCLUSIONS: Low aminotransferases during treatment are associated with a better long-term survival in autoimmune hepatitis. IgG was not associated with survival in first 12 months of treatment. Normalization of aminotransferases should be the treatment goal for autoimmune hepatitis to improve long-term survival. Show less
Biewenga, M.; Verhelst, X.; Baven-Pronk, M.; Putter, H.; Berg, A. van den; Colle, I.; ... ; Dutch Autoimmune Hepatitis Study G 2022
Background & AimsBiochemical remission, important treatment goal in autoimmune hepatitis (AIH), has been associated with better long-term survival. The aim of this study was to determine the... Show moreBackground & AimsBiochemical remission, important treatment goal in autoimmune hepatitis (AIH), has been associated with better long-term survival. The aim of this study was to determine the independent prognostic value of aminotransferases and immunoglobulin G (IgG) during treatment on long-term transplant-free survival in AIH.MethodsIn a multicenter cohort alanine aminotransferase, aspartate aminotransferase (AST), and IgG were collected at diagnosis and 6, 12, 24, and 36 months after start of therapy and related to long-term outcome using Kaplan-Meier survival and Cox regression analysis with landmark analysis at these time points, excluding patients with follow-up ending before each landmark.ResultsA total of 301 AIH patients with a median follow-up of 99 (range, 7–438) months were included. During follow-up, 15 patients required liver transplantation and 33 patients died. Higher AST at 12 months was associated with worse survival (hazard ratio [HR], 1.86; P < .001), while IgG was not associated with survival (HR, 1.30; P = .53). In multivariate analysis AST at 12 months (HR, 2.13; P < .001) was predictive for survival independent of age, AST at diagnosis and cirrhosis. Multivariate analysis for AST yielded similar results at 6 months (HR, 2.61; P = .001), 24 months (HR, 2.93; P = .003), and 36 months (HR, 3.03; P = .010). There was a trend toward a worse survival in patients with mildly elevated aminotransferases (1–1.5× upper limit of normal) compared with patients with normal aminotransferases (P = .097).ConclusionsLow aminotransferases during treatment are associated with a better long-term survival in autoimmune hepatitis. IgG was not associated with survival in first 12 months of treatment. Normalization of aminotransferases should be the treatment goal for autoimmune hepatitis to improve long-term survival. Show less
Peereboom, E.T.M.; Matern, B.M.; Tomosugi, T.; Niemann, M.; Drylewicz, J.; Joosten, I.; ... ; Spierings, E. 2021
CD4(+) T-helper cells play an important role in alloimmune reactions following transplantation by stimulating humoral as well as cellular responses, which might lead to failure of the allograft.... Show moreCD4(+) T-helper cells play an important role in alloimmune reactions following transplantation by stimulating humoral as well as cellular responses, which might lead to failure of the allograft. CD4(+) memory T-helper cells from a previous immunizing event can potentially be reactivated by exposure to HLA mismatches that share T-cell epitopes with the initial immunizing HLA. Consequently, reactivity of CD4(+) memory T-helper cells toward T-cell epitopes that are shared between immunizing HLA and donor HLA could increase the risk of alloimmunity following transplantation, thus affecting transplant outcome. In this study, the amount of T-cell epitopes shared between immunizing and donor HLA was used as a surrogate marker to evaluate the effect of donor-reactive CD4(+) memory T-helper cells on the 10-year risk of death-censored kidney graft failure in 190 donor/recipient combinations using the PIRCHE-II algorithm. The T-cell epitopes of the initial theoretical immunizing HLA and the donor HLA were estimated and the number of shared PIRCHE-II epitopes was calculated. We show that the natural logarithm-transformed PIRCHE-II overlap score, or Shared T-cell EPitopes (STEP) score, significantly associates with the 10-year risk of death-censored kidney graft failure, suggesting that the presence of pre-transplant donor-reactive CD4(+) memory T-helper cells might be a strong indicator for the risk of graft failure following kidney transplantation. Show less