Recognition of microbial and mammalian phospholipid antigens by NKT cells with diverse TCRs

• CD1d-restricted natural killer T (NKT) cells include two major subgroups. The most widely studied are V alpha 14J alpha 18(+) invariant NKT (iNKT) cells that recognize the prototypical alpha-galactosylceramide antigen, whereas the other major group uses diverse T-cell receptor (TCR) alpha-and beta-chains, does not recognize alpha-galactosylceramide, and is referred to as diverse NKT (dNKT) cells. dNKT cells play important roles during infection and autoimmunity, but the antigens they recognize remain poorly understood. Here, we identified phosphatidylglycerol (PG), diphosphatidylglycerol (DPG, or cardiolipin), and phosphatidylinositol from Mycobacterium tuberculosis or Corynebacterium glutamicum as microbial antigens that stimulated various dNKT, but not iNKT, hybridomas. dNKT hybridomas showed distinct reactivities for diverse antigens. Stimulation of dNKT hybridomas by microbial PG was independent of Toll-like receptor-mediated signaling by antigen-presenting cells and required lipid uptake and/or processing. Furthermore, microbial PG bound to CD1d molecules and plate-bound PG/CD1d complexes stimulated dNKT hybridomas, indicating direct recognition by the dNKT cell TCR. Interestingly, despite structural differences in acyl chain composition between microbial and mammalian PG and DPG, lipids from both sources stimulated dNKT hybridomas, suggesting that presentation of microbial lipids and enhanced availability of stimulatory self-lipids may both contribute to dNKT cell activation during infection.

Ämnesord

MEDICIN OCH HÄLSOVETENSKAP  -- Medicinska och farmaceutiska grundvetenskaper -- Mikrobiologi inom det medicinska området (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Basic Medicine -- Microbiology in the medical area (hsv//eng)

Nyckelord

type II natural killer T cell

CD1 antigen presentation

innate immunity

adaptive immunity

killer t-cells

innate-like

receptor

cd1

repertoire

sulfatide

distinct

glycolipids

population

activation

Kawakami

KazuyoshiKawakami

KNizet

VictorNizet

VBesra

Gurdyal S.Besra

GSTsuji

MoriyaTsuji

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)