Immunophenotyping of peripheral immunoregulatory as well as Th17A and Th22 cell subpopulations in kidney transplant recipients under belatacept or cyclosporine treatment.

OBJECTIVE: Regulatory Foxp3-expressing T cells (Tregs), IL-10-producing B cells (Bregs), and IDO-expressing dendritic cells (DCregs) downregulate inflammatory processes and induce peripheral tolerance, while Th17A and Th22 cell subpopulations are of proinflammatory nature. The aims of the study were to characterize and to enumerate peripheral Tregs, Bregs, and DCregs and Th17A and Th22 cell subpopulations in kidney transplant recipients (KTRs) under belatacept or cyclosporine treatment. METHODS: Forty-one KRT patients (30 under belatacept treatment and 11 under cyclosporine treatment) and 26 healthy donors (HDs) were included in the study. CD19(+)-expressing peripheral B lymphocytes were purified by positive selection. IL-10-producing B cells, CD4(+)/CD25(high)Foxp3(+), and CD8(+)/CD28(-)Foxp3(+) Tregs, CCR6(+)/CD123(+)/IDO(+) DCs, as well as Th17A and Th22 cell subpopulations were quantitated by flow cytometry. RESULTS: Of the IL-10-producing Bregs, CD19(+)/CD24(high)/CD38(high)/CD5(+), CD19(+)/CD24(high)/CD38(high)/CD10(+), CD19(+)/CD24(high)/CD38(high)/CD20(+), and CD19(+)/CD24(high)/CD38(high)/CD27(-) had significant higher frequency in patients under belatacept treatment when compared with those under cyclosporine. Only CD19(+)/CD24(high)/CD38(high)/CD27(+) and CD19(+)/CD24(high)/CD38(high)/CXCR7(+) cells had significant higher frequency in patients under cycloporine treatment when compared to those under belatacept. The percentages of IDO-expressing pDC, CD4(+)/CD25(high)Foxp3(+), and CD8(+)/CD28(-)Foxp3(+) were significantly higher in the belatacept group when compared the cyclosporine one, while Th17A and Th22 cells had significant higher frequency in the latter group. CONCLUSION: Belatacept seems to maintain and enhance, at least systemically, a tolerant profile to renal allograft in transplant recipients by means of higher circulatory frequencies of regulatory B, T and pDC subpopulations.

Renal transplant recipient with advanced HIV infection: graft and peripheral cell population analysis.

The scenario of a renal transplant recipient who is diagnosed with HIV infection in the late post transplant period is very uncommon. The viral infection effect on immunologic stability, regulatory cells, and allogeneic response during immune quiescence and graft acceptance provides a fertile ground in organ transplantation research and translational immunology.

Peripheral regulatory cells immunophenotyping in kidney transplant recipients with different clinical profiles: a cross-sectional study.

Regulatory Foxp3-expressing T cells (Tregs), IL-10-producing B cells (Bregs), and IDO-expressing dendritic cells (DCregs) downregulate inflammatory processes and induces peripheral tolerance. These subpopulations also might participate in maintaining allograft immunological quiescence in kidney transplant recipients (KTRs) with an excellent long-term graft function under immunosuppression (ELTGF). The aim of the study was to characterize and to enumerate peripheral Tregs, Bregs, and DCregs in KTR with an ELTGF for more than 5 years after transplant. Fourteen KTR with an ELTGF, 9 KTR with chronic graft dysfunction (CGD), and 12 healthy donors (HDs) were included in the study. CD19(+)-expressing peripheral B lymphocytes were purified by positive selection. IL-10-producing B cells, CD4(+)/CD25(hi), and CD8(+)/CD28(-) Tregs, as well as CCR6(+)/CD123(+)/IDO(+) DCs, were quantitated by flow cytometry. IL-10-producing Bregs (immature/transitional, but not CD19(+)/CD38(hi)/CD24(hi)/CD27(+)B10 cells), CCR6(+)/CD123(+)/IDO(+) DCs, and Tregs from ELTGF patients had similar or higher percentages versus HD (P < 0.05). By contrast, number of Tregs, DCregs, and Bregs except for CD27(+)B10 cells from CGD patients had lower levels versus HD and ELTGF patients (P < 0.05). The findings of this exploratory study might suggest that in ELTGF patients, peripheral tolerance mechanisms could be directly involved in the maintenance of a quiescent immunologic state and graft function stability.