Transforming growth factor-beta suppresses activation and proliferation of microglia in vitro.
Transforming growth factor-beta (TGF-beta) has been shown to be produced in the central nervous system (CNS). The functions of TGF-beta, however, remain to be elucidated. We investigated the effects of TGF-beta on the proliferation, activation, and cytokine production of isolated microglia in vitro. TGF-beta dose-dependently suppressed the acid phosphatase activity of and formation of superoxide anion by LPS activated microglia. It also suppressed the IFN-gamma-induced expression of class II MHC Ag- and the production of cytokines, IL-1, IL-6, and TNF-alpha, by these cells. TGF-beta also inhibited the proliferation of microglia that was induced by either GM-CSF or M-CSF. Because various immunoregulatory cytokines are produced in the CNS that serve as autocrine or paracrine mediators it is suggested that TGF-beta could be a negative regulator in the CNS cytokine network. It may play a role in the development of various disease processes in the CNS by inhibiting the function of microglia in inflammation or in immunoregulation.
Suzumura
A
A
Department of Neurology, School of Medicine, Fujita Health University, Aichi, Japan.
Sawada
M
M
Yamamoto
H
H
Marunouchi
T
T
D000818:Animals; D001483:Base Sequence; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D016207:Cytokines / Q000235:genetics*; D015870:Gene Expression / Q000187:drug effects; D005802:Genes, MHC Class II; D000949:Histocompatibility Antigens Class II / Q000235:genetics*; D066298:In Vitro Techniques; D051379:Mice; D008809:Mice, Inbred C3H; D008969:Molecular Sequence Data; D009457:Neuroglia / Q000166:cytology / Q000502:physiology*; D009838:Oligodeoxyribonucleotides / Q000737:chemistry; D016212:Transforming Growth Factor beta / Q000494:pharmacology*
D016207:Cytokines; D000949:Histocompatibility Antigens Class II; D009838:Oligodeoxyribonucleotides; D016212:Transforming Growth Factor beta