Azacytidine mitigates experimental sclerodermic chronic graft-versus-host disease

Abstract

BackgroundPrevious studies have demonstrated that regulatory T cells (Tregs) play a protective role in the pathogenesis of chronic graft-versus-host disease (cGVHD). Tregs constitutively express the gene of the transcription factor Foxp3 whose CNS2 region is heavily methylated in conventional CD4+ T cells (CD4+Tconvs) but demethylated in Tregs.MethodsHere, we assessed the impact of azacytidine (AZA) on cGVHD in a well-established murine model of sclerodermic cGVHD (B10.D2 (H-2d) → BALB/cJ (H-2d)).ResultsThe administration of AZA every 48 h from day +10 to day +30 at the dose of 0.5 mg/kg or 2 mg/kg mitigated chronic GVHD. Further, AZA-treated mice exhibited higher blood and thymic Treg frequencies on day +35, as well as higher demethylation levels of the Foxp3 enhancer and the IL-2 promoter in splenocytes at day +52. Interestingly, Tregs from AZA-treated mice expressed more frequently the activation marker CD103 on day +52. AZA-treated mice had also lower counts of CD4+Tconvs and CD8+ T cells from day +21 to day +35 after transplantation, as well as a lower proportion of CD4+Tconvs expressing the Ki67 antigen on day +21 demonstrating an anti-proliferating effect of the drug on T cells.ConclusionsOur results indicate that AZA prevented sclerodermic cGVHD in a well-established murine model of cGVHD. These data might serve as the basis for a pilot study of AZA administration for cGVHD prevention in patients at high risk for cGVHD.Electronic supplementary materialThe online version of this article (doi:10.1186/s13045-016-0281-2) contains supplementary material, which is available to authorized users.

Acute Thymic Involution and Mechanisms for Recovery

“…For instance, TBTC induces stress in the endoplasmic reticulum (Isomura et al 2013) and thereby causes the death of murine thymocytes (Sharma and Kumar 2014). The chemotherapeutic drug, 5-azacytidine has an anti-proliferative effect on T cell expansion (Fransolet et al 2016) and induces thymocyte death and ATI through a TNF-related apoptosis-inducing ligand-based mechanism (Pozzesi et al 2014;Tochitani et al 2011). It thus causes chemotherapy-mediated cytotoxicity and immuno-suppression in mice (Yu et al 2016).…”

Occurrence of graft‐versus‐host disease increases mortality after umbilical cord blood transplantation for acute myeloid leukaemia: a report from Eurocord and the ALWP of the EBMT

“…This suggests that graftversus-leukaemia effects are the main mechanisms protecting for late relapses after UCBT. Other approaches to decrease relapse incidence after CBT might include posttransplant administration of disease-targeted medications [36][37][38][39] or of chimeric antigen receptor T cells [40].…”

Limited Impact of Imatinib in a Murine Model of Sclerodermatous Chronic Graft-versus-Host Disease

“…Twelve to 14 week-old B10.D2 (H-2 d , Jackson Laboratories, Bar Harbor, USA) and Balb/cJ (H-2 d , Jackson Laboratories) mice were used as donors and recipients, respectively, in a MHC-matched minor antigens disparate scl-cGvHD model [30, 31]. All mice were maintained in top-filtered cages in a standard animal facility and provided with sterilized food.…”

“…Balb/cJ recipient mice were transplanted as previously described [31]. Briefly, recipient Balb/cJ mice (H-2 d ) were lethally irradiated with 7 Gy total body irradiation using a 137 Cs irradiator (GammaCell 40, Nordion, Ontario, Canada).…”

“…Briefly, recipient Balb/cJ mice (H-2 d ) were lethally irradiated with 7 Gy total body irradiation using a 137 Cs irradiator (GammaCell 40, Nordion, Ontario, Canada). Six hours later, recipients were injected with 200 μL of the prepared cell suspension (2x10 6 spleen cells + 1x10 6 bone marrow cells for the moderate scl-cGVHD model [32] or 70x10 6 spleen cells + 10x10 6 bone marrow cells for the severe scl-cGVHD model [31, 33]) from B10.D2 (H-2 d ) mice. Recipient mice were monitored daily, while recipient body weights and GVHD scores (see next section) were recorded every 3 days.…”