Recombinant Human T-cell differentiation antigen CD6 (CD6), partial (Active)

Function

Cell adhesion molecule that mediates cell-cell contacts and regulates T-cell responses via its interaction with ALCAM/CD166 (PubMed:15048703, PubMed:15294938, PubMed:16352806, PubMed:16914752, PubMed:24584089, PubMed:24945728). Contributes to signaling cascades triggered by activation of the TCR/CD3 complex (PubMed:24584089). Functions as a costimulatory molecule; promotes T-cell activation and proliferation (PubMed:15294938, PubMed:16352806, PubMed:16914752). Contributes to the formation and maturation of the immunological synapse (PubMed:15294938, PubMed:16352806). Functions as a calcium-dependent pattern receptor that binds and aggregates both Gram-positive and Gram-negative bacteria. Binds both lipopolysaccharide (LPS) from Gram-negative bacteria and lipoteichoic acid from Gram-positive bacteria (PubMed:17601777). LPS binding leads to the activation of signaling cascades and down-stream MAP kinases (PubMed:17601777). Mediates activation of the inflammatory response and the secretion of pro-inflammatory cytokines in response to LPS (PubMed:17601777)

Subcellular Location

Secreted

Tissue Specificity

Detected on thymocytes (PubMed:15294938). Detected on peripheral blood T-cells (PubMed:15048703, PubMed:16352806). Detected on natural killer (NK) cells (PubMed:16352806). Soluble CD6 is detected in blood serum (at protein level) (PubMed:17601777). Detected in spleen, thymus, appendix, lymph node and peripheral blood leukocytes (PubMed:9013954). Expressed by thymocytes, mature T-cells, a subset of B-cells known as B-1 cells, and by some cells in the brain

Subunit

Interacts (via extracellular domain) with ALCAM/CD166 (via extracellular domain) (PubMed:15048703, PubMed:16352806, PubMed:16914752, PubMed:24945728, PubMed:26146185). Interacts with the TCR/CD3 complex subunit CD3E (PubMed:15294938). Interacts (via tyrosine phosphorylated C-terminus) with LCP2 (via SH2 domain) (PubMed:16914752). Interacts with VAV1 (By similarity). Interacts (via glycosylated extracellular domain) with LGALS1 and LGALS3 (PubMed:24945728). Interaction with LGALS1 or LGALS3 inhibits interaction with ALCAM (PubMed:24945728)

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• Taylor T.D. et al. Human chromosome 11 DNA sequence and analysis including novel gene identification. — Nature (2006)
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• Castro M.A. et al. Extracellular isoforms of CD6 generated by alternative splicing regulate targeting of CD6 to the immunological synapse. — J. Immunol. (2007)
• Swack J.A. et al. Biosynthesis and post-translational modification of CD6, a T cell signal-transducing molecule. — J. Biol. Chem. (1991)
• Wee S. et al. Tyrosine phosphorylation of CD6 by stimulation of CD3: augmentation by the CD4 and CD2 coreceptors. — J. Exp. Med. (1993)
• Hassan N.J. et al. Frontline: Optimal T cell activation requires the engagement of CD6 and CD166. — Eur. J. Immunol. (2004)
• Gimferrer I. et al. Relevance of CD6-mediated interactions in T cell activation and proliferation. — J. Immunol. (2004)