Lag - 3 , a Novel Lymphocyte Activation Gene
نویسندگان
چکیده
A number of cell surface structures are thought to belong to the Ig superfamily (IgSF) t because they contain at least one domain with a characteristic folding pattern, called the Ig fold (reviewed in reference 1) . Several of these molecules have critical functions in immune responses . In addition to ensuring specific antigen recognition (Ig, TCR), they may function as monomorphic ligands critical in cell-cell interactions (e.g ., ICAM, CD4, CD8), receptors for viruses (e.g ., CD4, ICAM), or lymphokine receptors (e.g ., IL-1-R, IL-6-R) . We report here the characterization of a novel human gene, termed lymphocyte activation gene 3 (LAG-3), selectively transcribed in activated NK and T lymphocytes . It codes for a membrane protein with four extracellular IgSF domains . The sequence data, the compared exon/intron organization, and the chromosomal localization revealed that LAG-3 is closely related to CD4.
منابع مشابه
CD3/TCR complex-associated lymphocyte activation gene-3 molecules inhibit CD3/TCR signaling.
The lymphocyte activation gene-3 (LAG-3) molecule is a T cell activation Ag closely related to CD4 at the gene and protein levels. We investigated whether LAG-3 itself may down-regulate the immune response by interfering with TCR signaling. The binding of Ab to the LAG-3 molecule followed by cross-linking (XL) inhibits cell proliferation and cytokine secretion in response to CD3XL on activated ...
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