Mixed chimerism and transplant tolerance are not effectively induced in C3a-deficient mice

Baśkiewicz-Hałasa, Magdalena; Rogińska, Dorota; Piecyk, Katarzyna; Hałasa, Maciej; Lejkowska, Renata; Pius-Sadowska, Ewa; Machaliński, Bogusław

doi:10.1016/j.exphem.2014.09.008

Cited by 1 publication

(1 citation statement)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…C5a/C5aR1 interactions activate DCs, manifested by increased expression of costimulatory molecule and innate cytokine production, which also contribute to Teff differentiation and expansion while inhibiting Tregs . Differential effects of complement/C5aR1 signaling on various cell types likely explain why the absence of complement components prevents graft tolerance under some experimental conditions, yet promotes tolerance to alloantigens in other circumstances . While we did not quantify IL‐17 or IL‐4 production by alloreactive T cells in these experiments, our previous work showed that complement activation augments the strength of the effector response (and inhibits the regulatory response) without altering cytokine profiles …”

Section: Discussionmentioning

confidence: 86%

C5aR1 regulates migration of suppressive myeloid cells required for costimulatory blockade-induced murine allograft survival

Llaudo

Fribourg

Medof

et al. 2019

American Journal of Transplantation

View full text Add to dashboard Cite

Costimulatory blockade-induced murine cardiac allograft survival requires intragraft accumulation of CD11b Ly6C Ly6G regulatory myeloid cells (Mregs) that expand regulatory T cells (Tregs) and suppress effector T cells (Teffs). We previously showed that C5a receptor (C5aR1) signaling on T cells activates Teffs and inhibits Tregs, but whether and/or how C5aR1 affects Mregs required for transplant survival is unknown. Although BALB/c hearts survived >60 days in anti-CD154 (MR1)-treated or cytotoxic T-lymphocyte associated protein 4 (CTLA4)-Ig-treated wild-type (WT) recipients, they were rejected at ~30 days in MR1-treated or CTLA4-Ig-treated recipients selectively deficient in C5aR1 restricted to myeloid cells (C5ar1 xLysM-Cre). This accelerated rejection was associated with ~2-fold more donor-reactive T cells and ~40% less expansion of donor-reactive Tregs. Analysis of graft-infiltrating mononuclear cells on posttransplant day 6 revealed fewer Ly6C monocytes in C5ar1 xLysM-Cre recipients. Expression profiling of intragraft Ly6C monocytes showed that C5aR1 deficiency downregulated genes related to migration/locomotion without changes in genes associated with suppressive function. Cotransfer of C5ar1 and C5ar1 xLysM-Cre myeloid cells into MR1-treated allograft recipients resulted in less accumulation of C5ar1 cells within the allografts, and in vitro assays confirmed that Ly6C myeloid cells migrate to C5a/C5aR1-initiated signals. Together, our results newly link myeloid cell-expressed C5aR1 to intragraft accumulation of myeloid cells required for prolongation of heart transplant survival induced by costimulatory blockade.

show abstract

Section: Discussionmentioning

confidence: 86%