The effect of high-mobility group box 1 protein on activity of regulatory T cells after thermal injury in rats.
The aim of the present study was to investigate in vivo the effect of high-mobility group box 1 protein (HMGB1) on activity of regulatory T cells (Tregs) and the influence on T-cell-mediated immunity after thermal injury. Male Wistar rats were randomly divided into four groups as follows: sham burn group, burn group, burn with ethyl pyruvate treatment group, and burn with antireceptor for advanced glycation end products (RAGE) antibody treatment group, and they were killed on postburn days 1, 3, 5, and 7, respectively, with eight animals at each time point. Magnetic cell sorting microbeads were used to isolate splenic Tregs and a column of nylon wool to obtain T cells. Phenotypes, including cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4), forkhead/winged helix transcription factor p3 (Foxp3), RAGE, and IL-2Ralpha, were analyzed by flow cytometry. Levels of HMGB1, IL-10, IL-2, IL-4 and interferon gamma were determined by enzyme-linked immunosorbent assay kits, and real-time reverse transcription-polymerase chain reaction was performed to detect mRNA expression of IL-10, IL-2, and IL-2Ralpha. Serum HMGB1 levels were significantly elevated during postburn days 1 to 7. In the burn group, CTLA-4 and Foxp3 expression levels of Tregs were strongly enhanced in comparison to the sham-injured group, and the capacity of Tregs to produce IL-10 was markedly increased. Administration of ethyl pyruvate to inhibit HMGB1 or anti-RAGE antibody could significantly decrease expression levels of CTLA-4, Foxp3 on Tregs, and IL-10 production after burns. Simultaneously, proliferative activity and expression levels of IL-2 and IL-2Ralpha of T cell were restored. The excessively released HMGB1 might stimulate CD4+CD25+Treg activity via binding RAGE on the surface of Tregs and trigger a shift of T(H)1 to T(H)2 with suppression of T-lymphocyte immune function after burn injury.
Huang
Li-Feng
LF
Department of Microbiology and Immunology, Burns Institute, First Hospital Affiliated to the Chinese PLA General Hospital, Beijing, People's Republic of China.
Yao
Yong-Ming
YM
Zhang
Li-Tian
LT
Dong
Ning
N
Yu
Yan
Y
Sheng
Zhi-Yong
ZY
D000818:Animals; D000906:Antibodies / Q000276:immunology / Q000494:pharmacology; D015703:Antigens, CD / Q000276:immunology / Q000378:metabolism; D002056:Burns / Q000276:immunology* / Q000378:metabolism; D060908:CTLA-4 Antigen; D049109:Cell Proliferation / Q000187:drug effects; D016207:Cytokines / Q000276:immunology / Q000378:metabolism; D051858:Forkhead Transcription Factors / Q000276:immunology / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects / Q000276:immunology*; D024243:HMGB1 Protein; D006609:High Mobility Group Proteins / Q000276:immunology* / Q000378:metabolism; D007108:Immune Tolerance / Q000187:drug effects / Q000276:immunology*; D053645:Interleukin-2 Receptor alpha Subunit / Q000276:immunology / Q000378:metabolism; D008297:Male; D011773:Pyruvates / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D000067759:Receptor for Advanced Glycation End Products; D011971:Receptors, Immunologic / Q000037:antagonists & inhibitors / Q000276:immunology; D012097:Repressor Proteins / Q000276:immunology* / Q000378:metabolism; D050378:T-Lymphocytes, Regulatory / Q000276:immunology* / Q000378:metabolism; D013997:Time Factors
D000906:Antibodies; D015703:Antigens, CD; D060908:CTLA-4 Antigen; C556708:Ctla4 protein, rat; D016207:Cytokines; D051858:Forkhead Transcription Factors; C500522:Foxp3 protein, rat; D024243:HMGB1 Protein; C104200:Hbp1 protein, rat; D006609:High Mobility Group Proteins; D053645:Interleukin-2 Receptor alpha Subunit; D011773:Pyruvates; D000067759:Receptor for Advanced Glycation End Products; D011971:Receptors, Immunologic; D012097:Repressor Proteins; C046522:ethyl pyruvate