Infusion of Lymphocytes Treated With 8-Methoxypsoralen and Ultraviolet A Light Induces CD19+IL-10+ Regulatory B Cells and Promotes Skin Allograft Survival

• Published in: Transplantation proceedings 2018-12, Vol.50 (10), p.3906-3910
• Main Authors: Wei, Y.X., Sun, B., Xiao, L., Shi, B.Y.
• Format: Article
• Language: English
• Subjects: Allografts - metabolism; Animals; B-Lymphocytes, Regulatory - immunology; Dendritic Cells - immunology; Immunosuppression - methods; Interleukin-10 - biosynthesis; Lymphocyte Transfusion - methods; Lymphocytes - drug effects; Lymphocytes - immunology; Lymphocytes - radiation effects; Male; Methoxsalen - pharmacology; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Photopheresis - methods; Skin Transplantation; Transplantation Tolerance - drug effects; Transplantation Tolerance - immunology; Transplantation Tolerance - radiation effects; Ultraviolet Rays
• ISSN: 0041-1345; 1873-2623
• DOI: 10.1016/j.transproceed.2018.04.066

Extracorporeal photopheresis (ECP) represents an alternative to immunosuppression as a means of reducing rejection after thoracic organ transplantation. The mechanism by which ECP exerts its protective effects, until now, has remained elusive. Infusion of ECP-treated splenic lymphocytes (PUVA-SP) can induce CD4+CD25highFoxp3+ regulatory T cells. However, the regulatory effect of PUVA-SP on B cells remains poorly understood. In the present study, we measured IL-10 secretion from CD19+ B cells of peripheral blood mononuclear cells. Our results demonstrate that infusion of PUVA-SP (PUVA-BSP from BALB/c or PUVA-CSP from C57BL/6 mice), in the absence of an immunosuppressant, significantly promotes skin allograft survival. This effect was associated with upregulation of circulating regulatory B cells exhibiting preferential IL-10 secretion and a shift of cytokine profile from helper T cell type 1 to helper T cell type 2. Our results suggest that effective treatments involving infusion of PUVA-SP is likely related not only to the modulation of T cell and regulatory T cell functions but also to the function of B cell and regulatory B cells. •PUVA efficiently induced early apoptosis of C57BL/6 or BALB/c splenic cells in mice.•Infusion of PUVA-SP induced preferential IL-10 secretion in B cells.•Infusion of PUVA-SP prolonged allograft skin survival.