High-mobility group box 1 promotes early acute allograft rejection by enhancing IL-6-dependent Th17 alloreactive response.
Previously, we reported that extracellular high-mobility group box 1 (HMGB1) functions as an innate alarmin implicated in cardiac allograft acute rejection. We now present evidence suggesting that HMGB1 is pivotal in inducing interleukin-17 (IL-17)-producing alloreactive T cells by stimulating dendritic cells secretion of IL-6. Those IL-17(+) T cells are likely to be the major effector cells responsible for the early stage of cardiac allograft rejection through mediating an influx of neutrophils into allografts, and therefore, blockade of IL-17A significantly prolonged murine cardiac allograft survival. In contrast to the classical model for a dominant role of IFN-γ(+)-Th1 cells have in acute allograft rejection, our data suggest that IFN-γ(+)-Th1 cells are responsible for the late stage of graft destruction by inducing monocyte infiltration when IL-17(+) T-cell response recedes. Blockade of HMGB1 significantly decreased splenic alloreactive Th17 cells and IFN-γ-producing CD8(+) T cells in the recipients, leading to less infiltration of neutrophils along with lower IL-6 and IL-17 expression levels in the grafts as well as prolongation of cardiac allograft survival. Together, these data support a novel model in which HMGB1 induces IL-17-producing alloreactive T cells to mediate early stage of allograft rejection, whereas IFN-γ-producing alloreactive Th1 cells provoke graft destruction after Th17 response recedes.
Duan
Lihua
L
Laboratory of Transplantation, Department of Immunology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
Wang
Cong-Yi
CY
Chen
Jie
J
Gong
Quan
Q
Zhu
Ping
P
Zheng
Fang
F
Tan
Zheng
Z
Gong
Feili
F
Fang
Min
M
D000208:Acute Disease; D000818:Animals; D057134:Antibodies, Neutralizing / Q000008:administration & dosage / Q000276:immunology; D002478:Cells, Cultured; D005260:Female; D005434:Flow Cytometry; D015870:Gene Expression; D006084:Graft Rejection / Q000276:immunology* / Q000517:prevention & control; D006085:Graft Survival / Q000187:drug effects / Q000276:immunology; D024243:HMGB1 Protein / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D016027:Heart Transplantation; D007371:Interferon-gamma / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D020381:Interleukin-17 / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D015850:Interleukin-6 / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013601:T-Lymphocytes / Q000276:immunology / Q000378:metabolism; D018417:Th1 Cells / Q000276:immunology / Q000378:metabolism; D058504:Th17 Cells / Q000276:immunology* / Q000378:metabolism; D014184:Transplantation, Homologous
D057134:Antibodies, Neutralizing; D024243:HMGB1 Protein; D020381:Interleukin-17; D015850:Interleukin-6; D007371:Interferon-gamma