Defective presentation of the CD1d1-restricted natural Va14Ja18 NKT lymphocyte antigen caused by β- d -glucosylceramide synthase deficiency

doi:10.1073/pnas.0430327100

Defective presentation of the CD1d1-restricted natural Va14Ja18 NKT lymphocyte antigen caused by β-d-glucosylceramide synthase deficiency

^*Department of Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN 37232; ^†Department of Microbiology and Immunology, Albert Einstein College of Medicine, Yeshiva University, Bronx, NY 10461; ^‡Department of Microbiology and Immunology and the Walther Oncology Centre, Indiana University School of Medicine, Indianapolis, IN 46202; ^§Walther Cancer Institute, Indianapolis, IN 46208; ^¶Laboratory for Memory and Learning, Institute of Physical and Chemical Research, Brain Science Institute, Saitama 351-0198, Japan; and ^‖Institute for Cancer Research, Fox Chase Cancer Institute, Philadelphia, PA 19111

Edited by Philippa Marrack, National Jewish Medical and Research Center, Denver, CO, and approved December 26, 2002 (received for review January 18, 2002)

Abstract

Va14Ja18 natural T (NKT) cells play an immunoregulatory role, which is controlled by a self glycolipid(s) presented by CD1d. Although the synthetic antigen α-D-galactosylceramide (α-D-GalCer) stimulates all Va14Ja18 NKT cells, α-anomeric D-glycosylceramides are currently unknown in mammals. We have used β-D-GalCer-deficient mice and β-D-glucosylceramide (β-D-GlcCer)-deficient cells to define the chemical nature of a natural NKT cell antigen. β-D-GalCer-deficient mice exhibit normal NKT cell development and function, and cells from these animals potently stimulate NKT hybridomas. In striking contrast, the same hybridomas fail to react to CD1d1 expressed by a β-D-GlcCer-deficient cell line. Importantly, human β-D-GlcCer synthase cDNA transfer, and hence the biosynthesis of β-D-GlcCer, restores the recognition of mutant cells expressing CD1d1 by the Va14Ja18 NKT hybridomas. Additionally, suppression of β-D-GlcCer synthesis inhibits antigen presentation to Va14Ja18 NKT cells. The possibility that β-D-GlcCer itself is the natural NKT cell antigen was excluded because it was unable to activate NKT hybridomas in a cell-free antigen-presentation assay. These findings suggest that β-D-GlcCer may play an important role in generating and/or loading a natural Va14Ja18 NKT antigen.

Footnotes

↵ ** To whom correspondence should be addressed. E-mail: sebastian.joyce{at}vanderbilt.edu.
This paper was submitted directly (Track II) to the PNAS office.
Abbreviations:

α-d-GalCer,

α-d-galactosylceramide;

β-d-GalCer,

β-d-galactosylceramide;

β-d-GlcCer,

β-d-glucosylceramide;

β-d-GlcSph,

β-d-glucosylsphingosine;

β2m,

β2-microglobulin;

NKT,

natural T;

PDMP,

(±)-threo-1-phenyl-2-decanoylamino-3-morpholino- 1-propanol hydrochloride;

PPMP,

dl-threo-1-phenyl-2-palmitoylamino-3-morpholino-1-propanol;

PI,

phosphatidylinositol;

sCD1d1,

soluble CD1d1;

Tcr,

T cell receptor