Search

Endogenous danger signals are increasingly recognized in the pathogenesis of graft-versus-host disease (GVHD). Uric acid (UA) is a known danger signal and is released from injured cells during conditioning for allogeneic hematopoietic stem cell transplantation (HSCT), but its role in GVHD is unclear. Here, we retrospectively analyze 228 consecutive patients with malignant diseases undergoing HSCT from 10/10-HLA-matched donors. Low UA levels at the time of HSCT (day 0) were significantly associated with acute GVHD grades II-IV in univariate (HR 0.836, p = 0.0072) and multivariate analyses (HR 0.815, p = 0.0047). There was no significant association between UA levels and overall survival, non-relapse mortality, and relapse. This is the first report demonstrating a negative association between UA levels and acute GVHD. Due to the easy assessment and established pharmaceutical modification of UA, our findings are potentially clinically relevant. Confirmation in independent cohorts and further investigations into underlying mechanisms, such as reduced antioxidative capacity in hypouricemia, are warranted.

Background: Gastrointestinal graft-versus-host disease (GvHD) is a potentially life-threatening complication after allogeneic stem cell transplantation (SCT). Since therapeutic options are still limited, a prophylactic approach seems to be warranted., Methods: In this randomised, double-blind-phase III trial, we evaluated the efficacy of budesonide in the prophylaxis of acute intestinal GvHD after SCT. The trial was registered at https://clinicaltrials.gov, number NCT00180089., Results: The crude incidence of histological or clinical stage 3-4 acute intestinal GvHD until day 100 observed in 91 (n =48 budesonide, n =43 placebo) evaluable patients was 12.5% (95% CI 3-22%) under treatment with budesonide and 14% (95% CI 4-25%) under placebo (p = 0.888). Histologic and clinical stage 3-4 intestinal GvHD after 12 months occurred in 17% (95% CI 6-28%) of patients in the budesonide group and 19% (CI 7-32%) in the placebo group (p = 0.853). Although budesonide was tolerated well, we observed a trend towards a higher rate of infectious complications in the study group (47.9% versus 30.2%, p = 0.085). The cumulative incidences at 12 months of intestinal GvHD stage >2 with death as a competing event (budesonide 20.8% vs. placebo 32.6%, p = 0.250) and the cumulative incidence of relapse (budesonide 20.8% vs. placebo 16.3%, p = 0.547) and non-relapse mortality (budesonide 28% (95% CI 15-41%) vs. placebo 30% (95% CI 15-44%), showed no significant difference within the two groups (p = 0.911). The trial closed after 94 patients were enrolled because of slow accrual. Within the limits of the final sample size, we were unable to show any benefit for the addition of budesonide to standard GvHD prophylaxis., Conclusions: Budesonide did not decrease the occurrence of intestinal GvHD in this trial. These results imply most likely that prophylactic administration of budenoside with pH-modified release in the terminal ileum is not effective.

Purpose: Steroid-refractory graft-versus-host disease (GVHD) is a major and often fatal complication after allogeneic stem-cell transplantation (alloSCT). Although the pathophysiology of steroid refractoriness is not fully understood, evidence is accumulating that endothelial cell stress is involved, and endothelial thrombomodulin (THBD) plays a role in this process. Here we assess whether single-nucleotide polymorphisms (SNPs) within the THBD gene predict outcome after alloSCT., Patients and Methods: Seven SNPs within the THBD gene were studied (rs1962, rs1042579, rs1042580, rs3176123, rs3176124, rs3176126, and rs3176134) in a training cohort of 306 patients. The relevant genotypes were then validated in an independent cohort (n = 321)., Results: In the training cohort, an increased risk of nonrelapse mortality (NRM) was associated with three of seven SNPs tested: rs1962, rs1042579 (in linkage disequilibrium with rs3176123), and rs1042580. When patients were divided into risk groups (one v no high-risk SNP), a strong correlation with NRM was observed (hazard ratio [HR], 2.31; 95% CI, 1.36 to 3.95; P = .002). More specifically, NRM was predicted by THBD SNPs in patients who later developed GVHD (HR, 3.03; 95% CI, 1.61 to 5.68; P < .001) but not in patients without GVHD. In contrast, THBD SNPs did not predict incidence of acute GVHD. Multivariable analyses adjusting for clinical variables confirmed the independent effect of THBD SNPs on NRM. All findings could be reproduced in the validation cohort., Conclusion: THBD SNPs predict mortality of manifest GVHD but not the risk of acquiring GVHD, supporting the hypothesis that endothelial vulnerability contributes to GVHD refractoriness., (© 2014 by American Society of Clinical Oncology.)

Background: Allogeneic hematopoietic stem cell transplantation (alloHSCT) is often performed in cases of advanced hematological diseases, but because of the associated mortality and a high risk of relapse it is life prolonging only in some patients., Patients and Methods: A retrospective multi-center analysis of 401 patients was conducted to analyze the variables associated with outcome after alloHSCT in advanced hematological diseases. The Cox proportional hazards model was used to assess the independence of overall survival (OS) and disease-free survival (DFS) from prognostic factors in a multivariate model., Results: The 5-year OS and DFS were 27.3 and 21.1% respectively. Multivariate analysis showed that the underlying malignancy had a significant influence on OS and DFS (p < 0.001 and p < 0.011, respectively), whereas development of severe acute graft versus host disease (GvHD) had a negative impact on OS (p < 0.001). Development of chronic GvHD showed a trend to a better OS (p = 0.085) and DFS (p = 0.199). No impact was seen for the intensity of conditioning., Conclusion: Development of chronic GvHD but not the conditioning regimen improved the outcome after alloHSCT for advanced malignancies, underlining the importance of immunological rather than cytotoxic effects., (Copyright © 2012 S. Karger AG, Basel.)

Background: The bacterial microflora aggravates graft-versus-host-disease (GvHD) after allogeneic stem cell transplantation, but the underlying mechanisms of manifestations of intestinal GvHD (iGvHD) in the gut remain poorly understood., Aim: To analyse the gut flora composition and the impact of bacterial sensing via Toll-like receptors (TLRs) in iGvHD., Methods: By mimicking clinical low-intensity conditioning regimens used in humans, a novel irradiation independent, treosulfan and cyclophosphamide-based murine allogeneic transplantation model was established. A global survey of the intestinal microflora by cultural and molecular methods was performed, the intestinal immunopathology in TLR-deficient recipient mice with iGvHD investigated and finally, the impact of anti-TLR9 treatment on iGvHD development assessed., Results: The inflammatory responses in iGvHD were accompanied by gut flora shifts towards enterobacteria, enterococci and Bacteroides/Prevotella spp. Analysis of iGvHD in MyD88(-/-), TRIF(-/-), TLR2/4(-/-), and TLR9(-/-) recipient mice showed that bacterial sensing via TLRs was essential for iGvHD development. Acute iGvHD was characterised by increasing numbers of apoptotic cells, proliferating cells, T cells and neutrophils within the colon. These responses were significantly reduced in MyD88(-/-), TLR2/4(-/-), TRIF(-/-) and TLR9(-/-) mice, as compared with wild-type controls. However, TRIF(-/-) and TLR2/4(-/-) mice were not protected from mortality, whereas TLR9(-/-) mice displayed increased survival rates. The important role of TLR9-mediated immunopathology was independently confirmed by significantly reduced macroscopic disease symptoms and colonic apoptosis as well as by reduced T-cell and neutrophil numbers within the colon after treatment with a synthetic inhibitory oligonucleotide., Conclusions: These results emphasise the critical role of gut microbiota, innate immunity and TLR9 in iGvHD and highlight anti-TLR9 strategies as novel therapeutic options.

CD4+CD25+ regulatory T cells (Tregs) control immune responses to self- and foreign antigens and play a pivotal role in autoimmune diseases, infectious and noninfectious inflammation, and graft rejection. Since recent experimental studies have indicated that Tregs were able to ameliorate graft-versus-host disease (GvHD), we analyzed the number of infiltrating Tregs in the intestinal mucosa as one site of GvH reactivity using immunoenzymatic labeling to enumerate FOXP3+ T cells in 95 intestinal biopsies from 49 allografted patients in comparison with healthy controls and patients with infectious inflammation. While patients with cytomegalovirus (CMV)-colitis or diverticulitis showed a concomitant increase of CD8+ effectors and Tregs, acute and chronic GvHD were characterized by the complete lack of a counter-regulation indicated by a FOXP3+/CD8+ T-cell ratio identical to healthy controls. In contrast, specimens without histologic signs of GvHD demonstrated increased numbers of FOXP3+ per CD8+ T cells, indicating that the potential for Treg expansion is principally maintained in allografted patients. Our findings provide evidence that GvHD is associated with an insufficient up-regulation of Tregs in intestinal GvHD lesions. The determination of FOXP3+/CD8+ ratio can be a helpful tool to discriminate GvHD from infectious inflammation after allogeneic stem cell transplantation.

Acute graft-versus-host disease (aGVHD) occurs in up to 80% of patients who undergo allogeneic stem cell transplantation (SCT) and contributes significantly to transplant-related mortality (TRM). We conducted a prospective phase II trial to assess the efficacy and feasibility of treating steroid-refractory aGVHD with basiliximab, a chimaeric monoclonal antibody directed against the alpha chain of the interleukin-2 (IL-2) receptor. Basiliximab was administered intravenously at a dose of 20 mg on days 1 and 4. Twenty-three patients were enrolled between October 1999 and July 2004. We found a primary overall response rate of 82.5% with four patients (17.5%) showing a complete response and 15 patients (65%) a partial response. Six patients were again treated successfully with an IL-2 receptor antagonist because of recurrence of aGVHD. The rates of infections, chronic GVHD, malignancy recurrence and 1-year TRM following immunosuppression with basiliximab were comparable with those found with other treatment modalities for aGVHD. We conclude that basiliximab is efficient and feasible for steroid-refractory aGVHD and merits further evaluation.