title: A novel function of adipocytes in lipid antigen presentation to iNKT cells.
abstract: Systemic low-grade chronic inflammation has been intensively investigated in obese subjects. Recently, various immune cell types, such as macrophages, granulocytes, helper T cells, cytotoxic T cells, and B cells, have been implicated in the pathogenesis of adipose tissue inflammation. However, the roles of invariant natural killer T cells (iNKT cells) and the regulation of iNKT cell activity in adipose tissue are not thoroughly understood. Here, we demonstrated that iNKT cells were decreased in number in the adipose tissue of obese subjects. Interestingly, CD1d, a molecule involved in lipid antigen presentation to iNKT cells, was highly expressed in adipocytes, and CD1d-expressing adipocytes stimulated iNKT cell activity through physical interaction. iNKT cell population and CD1d expression were reduced in the adipose tissue of obese mice and humans compared to those of lean subjects. Moreover, iNKT cell-deficient Jα18 knockout mice became more obese and exhibited increased adipose tissue inflammation at the early stage of obesity. These data suggest that adipocytes regulate iNKT cell activity via CD1d and that the interaction between adipocytes and iNKT cells may modulate adipose tissue inflammation in obesity.
authors.affiliation: School of Biological Science, Institute of Molecular Biology & Genetics, Seoul National University, Seoul, South Korea.
authors.forename: Jin Young
authors.initials: JY
authors.lastname: Huh
authors.forename: Jong In
authors.initials: JI
authors.lastname: Kim
authors.forename: Yoon Jeong
authors.initials: YJ
authors.lastname: Park
authors.forename: In Jae
authors.initials: IJ
authors.lastname: Hwang
authors.forename: Yun Sok
authors.initials: YS
authors.lastname: Lee
authors.forename: Jee Hyung
authors.initials: JH
authors.lastname: Sohn
authors.forename: Sung Kyu
authors.initials: SK
authors.lastname: Lee
authors.forename: Assim A
authors.initials: AA
authors.lastname: Alfadda
authors.forename: Su Sung
authors.initials: SS
authors.lastname: Kim
authors.forename: Sung Hee
authors.initials: SH
authors.lastname: Choi
authors.forename: Dong-Sup
authors.initials: DS
authors.lastname: Lee
authors.forename: Se-Ho
authors.initials: SH
authors.lastname: Park
authors.forename: Rho Hyun
authors.initials: RH
authors.lastname: Seong
authors.forename: Cheol Soo
authors.initials: CS
authors.lastname: Choi
authors.forename: Jae Bum
authors.initials: JB
authors.lastname: Kim
mesh_terms: D041721:3T3-L1 Cells; D017667:Adipocytes / Q000276:immunology / Q000378:metabolism*; D000273:Adipose Tissue / Q000276:immunology / Q000378:metabolism; D000818:Animals; D017951:Antigen Presentation / Q000276:immunology*; D055610:Antigens, CD1d / Q000235:genetics / Q000276:immunology; D002908:Chronic Disease; D006801:Humans; D007249:Inflammation / Q000276:immunology; D008055:Lipids / Q000276:immunology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008820:Mice, Obese; D055611:Natural Killer T-Cells / Q000276:immunology* / Q000378:metabolism*; D009765:Obesity / Q000276:immunology / Q000378:metabolism; D047495:PPAR gamma / Q000235:genetics / Q000378:metabolism
chemical_list: D055610:Antigens, CD1d; C526879:Cd1d1 protein, mouse; D008055:Lipids; D047495:PPAR gamma