The immunosuppressive effect of gossypol in mice is mediated by inhibition of lymphocyte proliferation and by induction of cell apoptosis.
OBJECTIVE
To investigate the immunosuppressive effect of gossypol in mice both in vitro and in vivo.


METHODS
The in vitro effect of gossypol on the proliferation of lymphocytes isolated from lymph nodes of BALB/c mice was determined by CFSE staining and by an MTS assay. Lymphocyte activation and lymphoblastic transformation were evaluated with immunostaining. Cell apoptosis was detected by Annexin-V and Hoechst 33342 staining. The in vivo immunosuppressive effect of gossypol on the DTH reaction was evaluated using a mouse DTH model induced by 2,4-dinitro-1-fluorobenzene (DNFB). The thickness of the ears was measured, and the histological changes of the mouse auricles were observed after hematoxylin-eosin staining. The proliferation capacity of lymphocytes from DTH mice was also assayed.


RESULTS
In vitro, gossypol could significantly inhibit the proliferation of mouse lymphocytes stimulated with phorbol ester plus ionomycin in a dose-dependent manner. Although the expression of the early activation antigen CD69 was not affected, the lymphoblastic transformation of both T and B lymphocyte subsets was significantly suppressed by gossypol. Moreover, gossypol could induce apoptosis of lymphocytes, and the effect was time- and dose-dependent. In vivo, the DTH reaction in mice was markedly alleviated by gossypol injected intraperitoneally. Lymphocytes from drug-treated DTH mice had a reduced proliferation capacity as compared with lymphocytes from untreated DTH mice. Gossypol treatment also markedly reduced the number of infiltrated lymphocytes in the auricles of DTH mice.


CONCLUSIONS
Gossypol exhibited immunosuppressive effects in mice, probably by inhibition of lymphocyte proliferation and by induction of cell apoptosis.
Xu
Wen-bin
WB
Institute of Tissue Transplantation and Immunology, Ji-nan University, Guangzhou, China.
Xu
Li-hui
LH
Lu
Hong-song
HS
Ou-Yang
Dong-yun
DY
Shi
Huan-jing
HJ
Di
Jing-fang
JF
He
Xian-hui
XH
D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D002478:Cells, Cultured; D004139:Dinitrofluorobenzene; D005260:Female; D006072:Gossypol / Q000494:pharmacology*; D006968:Hypersensitivity, Delayed / Q000139:chemically induced / Q000188:drug therapy; D007166:Immunosuppressive Agents / Q000494:pharmacology*; D008213:Lymphocyte Activation / Q000187:drug effects*; D051379:Mice; D008807:Mice, Inbred BALB C
D007166:Immunosuppressive Agents; D004139:Dinitrofluorobenzene; D006072:Gossypol