Leptin inhibits mitogen-induced proliferation of peripheral T lymphocytes from Holstein cows.
This study examined the mitogenic response of bovine peripheral T lymphocytes to leptin, a pleiotropic hormone regulating food intake and energy expenditure. Leptin alone slightly suppressed proliferation of T lymphocytes in the presence of concanavalin A (ConA). Leptin also inhibited proliferation of T lymphocytes induced by anti-CD3 antibody. ConA treatment activated some protein kinases, including p44/p42(MAPK) and Akt/PKB, while anti-CD3 antibody treatment increased mRNA expression of suppressor of cytokine signalling (SOCS) 3, interferon (IFN)gamma, interleukin (IL) 2 and IL4 in T lymphocytes. Leptin alone increased only SOCS3 mRNA expression. Simultaneous treatment with mitogens and leptin enhanced IFNgamma mRNA expression but decreased IL2 mRNA expression, without any synergistic effect on phosphorylation of protein kinases or mRNA expression of SOCS3 and IL4. These results suggest that leptin modulates bovine T lymphocyte functions.
Ahmed
Mohamed
M
Department of Biomedical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo 060-0818, Japan.
Kimura
Kazuhiro
K
Soliman
Mohamed
M
Yamaji
Daisuke
D
Okamatsu-Ogura
Yuko
Y
Ishioka
Katsumi
K
Makondo
Kennedy
K
Hagiwara
Katsuro
K
Saito
Masayuki
M
D000818:Animals; D002417:Cattle; D049109:Cell Proliferation / Q000187:drug effects*; D003208:Concanavalin A; D016207:Cytokines / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology; D005260:Female; D020738:Leptin / Q000494:pharmacology*; D008213:Lymphocyte Activation; D008934:Mitogens / Q000037:antagonists & inhibitors; D011494:Protein Kinases / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D015398:Signal Transduction; D013601:T-Lymphocytes / Q000166:cytology* / Q000187:drug effects
D016207:Cytokines; D020738:Leptin; D008934:Mitogens; D003208:Concanavalin A; D011494:Protein Kinases