Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06126 (CD1a)
 2,221 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The cutaneous lymphocyte-associated antigen (CLA), recognized by the monoclonal antibody HECA-452, is a cell surface glycoprotein that binds specifically to E-selectin. CLA is present on most T cells at sites of cutaneous immune response and has been shown to be important in lymphocyte homing to the skin. It is expressed only by a minor subset of peripheral T cells and is absent on thymocytes. We have analysed (using a FACScan flow cytometer) the expression of CLA on human lymph cells derived from normal skin, from ultraviolet (UV)-irradiated skin and from allergic contact dermatitis. Whereas in the peripheral blood CLA was expressed on < 20% of CD4 +, CD8 + and CD56 + cells (natural killer cells), > 60% of CD4 +, CD8 + and CD56 + cells isolated from skin-derived lymph expressed CLA. Furthermore, > 90% of CD1a + dendritic lymph cells were positive for CLA. UV irradiation of the skin and induction of an allergic contact dermatitis did not change CLA expression on lymph cells, although lymph flow and cell output increased. These results provide further evidence for an important role of CLA in cell homing to the skin.
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PMID:The HECA-452 epitope is highly expressed on lymph cells derived from human skin. 1058 71

Dendritic cells (DC) are potent APCs that sample Ags from the surrounding environment and present them to naive T cells using cell surface Ag-presenting molecules. The DC in both lymphoid and nonlymphoid tissues express high levels of CD1, a cell surface glycoprotein capable of presenting lipids and glycolipids to T cells. Distinct group 1 CD1 isoforms (CD1a, -b, -c) in man are known to traffic to different parts of the endocytic system where microbial Ags may be sampled. Guinea pigs are the only known rodent species that express the group 1 CD1 proteins. Therefore, we examined the expression and trafficking of guinea pig CD1 (gpCD1) isoforms on isolated DC. Confocal microscopy using mAbs specific for individual gpCD1 isoforms revealed differential trafficking of two distinct CD1b isoforms within DC. Colocalization of MHC class II was observed with the gpCD1b1 isoform, consistent with localization in the late endosomes of DC. In contrast, the gpCD1b3 isoform lacks an endosomal sorting motif and remains on the cell surface. Following incubation with Mycobacterium tuberculosis lipoarabinomannan, colocalization of endocytosed lipoarabinomannan with the gpCD1b1 isoform was observed but not with the gpCD1b3 isoform, which remained primarily on the cell surface. These data demonstrate that guinea pig DC express CD1 isoforms with unique trafficking patterns that recapitulate the patterns seen for human CD1 isoforms. This suggests evolutionary pressure for a conserved mechanism in mammals that allows CD1 to sample lipid Ags from various subcompartments of the endocytic system.
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PMID:Conservation of CD1 intracellular trafficking patterns between mammalian species. 1247 Nov 29