Resource Logo
NLM AIDSLINE

The nonclassical class I molecule CD1d associates with the novel CD8 ligand gp180 on intestinal epithelial cells.




 

J Biol Chem. 1999 Sep 10;274(37):26259-65. Unique Identifier : AIDSLINE

Previous studies have shown that normal intestinal epithelial cells (IECs) are able to selectively activate CD8(+) T cells with suppressor activity, inducing proliferation associated with the activation of both the CD8-associated kinase p56(lck) and the T cell receptor (TCR)-associated kinase p59(fyn). This process appears to relate in part to a 180-kDa IEC surface glycoprotein, gp180, which binds to CD8 and activates CD8-associated p56(lck). However, purified gp180 alone is unable to induce T cell proliferation and does not activate p59(fyn). Because the class Ib molecule CD1d is expressed by IECs and monoclonal antibodies (mAbs) against CD1d inhibit IEC-induced proliferation of CD8(+) T cells, co-immunoprecipitation and enzyme-linked immunosorbent assay studies were performed, which demonstrated an association of gp180 and CD1d on the IEC surface. Interestingly, the activation of p59(fyn) in IEC-T cell co-cultures was blocked by the anti-CD1d mAb D5 but not by the anti-gp180 mAb B9. Conversely, treatment of IECs with mAb B9 inhibited IEC-induced activation of p56(lck) but not p59(fyn). More directly, a human CD1d cDNA (FO-1 D5) transfectant was able to activate p59(fyn) but not p56(lck). These data suggest that the CD1d-gp180 complex on the surface of IECs can be recognized by the TCR-CD8 co-receptor, resulting in the activation of CD8(+) T cells.

JOURNAL ARTICLE Antibodies, Monoclonal/IMMUNOLOGY Antigens, CD1/IMMUNOLOGY/*METABOLISM Cell Line Coculture CD8-Positive T-Lymphocytes/*METABOLISM Enzyme Activation Glycoproteins/*METABOLISM Human Intestinal Mucosa/METABOLISM Lymphocyte Specific Protein Tyrosine Kinase p56(lck)/METABOLISM Lymphocyte Transformation Proto-Oncogene Proteins/METABOLISM Support, Non-U.S. Gov't Support, U.S. Gov't, P.H.S.



 




Information in this article was accurate in December 30, 1999. The state of the art may have changed since the publication date. This material is designed to support, not replace, the relationship that exists between you and your doctor. Always discuss treatment options with a doctor who specializes in treating HIV.