title: Metformin Suppresses MHC-Restricted Antigen Presentation by Inhibiting Co-Stimulatory Factors and MHC Molecules in APCs.
abstract: Metformin is widely used for T2D therapy but its cellular mechanism of action is undefined. Recent studies on the mechanism of metformin in T2D have demonstrated involvement of the immune system. Current immunotherapies focus on the potential of immunomodulatory strategies for the treatment of T2D. In this study, we examined the effects of metformin on the antigen-presenting function of antigen-presenting cells (APCs). Metformin decreased both MHC class I and class II-restricted presentation of OVA and suppressed the expression of both MHC molecules and co-stimulatory factors such as CD54, CD80, and CD86 in DCs, but did not affect the phagocytic activity toward exogenous OVA. The class II-restricted OVA presentation-regulating activity of metformin was also confirmed using mice that had been injected with metformin followed by soluble OVA. These results provide an understanding of the mechanisms of the T cell response-regulating activity of metformin through the inhibition of MHC-restricted antigen presentation in relation to its actions on APCs.
authors.affiliation: College of Pharmacy, Sahmyook University, Seoul 139-742, Republic of Korea.
authors.forename: Seulmee
authors.initials: S
authors.lastname: Shin
authors.forename: Bobae
authors.initials: B
authors.lastname: Hyun
authors.forename: Aeri
authors.initials: A
authors.lastname: Lee
authors.forename: Hyunseok
authors.initials: H
authors.lastname: Kong
authors.forename: Shinha
authors.initials: S
authors.lastname: Han
authors.forename: Chong-Kil
authors.initials: CK
authors.lastname: Lee
authors.forename: Nam-Joo
authors.initials: NJ
authors.lastname: Ha
authors.forename: Kyungjae
authors.initials: K
authors.lastname: Kim
keywords: Antigen-presenting cells; MHC-restricted antigen presentation; Metformin