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

The expression of membrane CD1c, as defined by monoclonal antibody L161, was examined on malignant lymphoid cells from 191 cases of chronic lymphoproliferative disease and on eight 'normal' enriched tonsil B-cell extracts. Of 79 cases of chronic lymphocytic leukaemia (CLL) studied, 77 showed low (less than 20% positive cells) CD1c expression whereas 63/71 (89%) cases of B-PLL, HCL and B-NHL showed increased CD1c+ (but not CD1a or CD1b) components. In contrast, malignancies corresponding to terminal stages of B-cell differentiation (immunocytoma and myeloma) generally showed low CD1c expression as did lymphoid cells from 10 cases of post-thymic malignancy. Although there was some correlation between the expression of membrane CD1c and immunoglobulin (SIg) light chain densities (P less than 0.001), it is relevant in diagnostic terms that seven cases of B-NHL with low SIg staining intensities more typically associated with CLL were CD1c+. CD1c expression was not, however, correlated with the presence of CD23 or FMC7 determinants but did show a similar pattern of expression to that previously reported for beta-2 microglobulin. Determination of cellular CD1c by APAAP immunocytochemistry confirmed the presence of higher antigen densities in malignant B-cells at intermediate/late stages of differentiation and this interpretation was further supported by the finding that the majority of phenotypically mature tonsil B-cells were also CD1c+. The determination of CD1c expression by malignant B-cells may therefore be of particular value in the diagnostic differentiation of chronic lymphoproliferative disorders.
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PMID:Diagnostic differentiation of chronic B-cell malignancies using monoclonal antibody L161 (CD1c). 278 56

To investigate the structure, function, and control of CD1a, we have cloned a 1.6-kbp cDNA which encodes the expressed CD1a protein and includes untranslated 5' and 3' sequences and the poly-A tail. As the protein recognized by the monoclonal antibody OKT6, CD1a is a useful marker for Langerhans cells (LC). CD1a is found on these cells and on thymocytes, suggesting an important immunologic role for this molecule. We constructed a cDNA library in lambda gt10 using mRNA from MOLT-4, a cell line that expresses the CD1a surface antigen. We then screened the library with an oligonucleotide synthesized according to a known partial sequence for CD1a, and subcloned the cDNA and its restriction fragments into pGEM for sequencing and probe production. Based on this sequence the CD1a protein is predicted to consist of three extracellular domains (alpha 1-3), a hydrophobic transmembrane region, and a cytoplasmic tail. DNA 5' to the alpha 1 region may undergo alternative exon splicing. There is high sequence identity between the beta-2 microglobulin binding region of MHC I molecules and CD1a. The secondary structure predicted for CD1a is very similar to the actual structure of HLA-A2, a classical MHC I molecule. The similarity includes the beta pleated sheets and alpha helices which form the antigen binding groove of the alpha-1 and alpha-2 domains. The homology predicted between CD1a and HLA-A2 in these regions appears to exist on the level of secondary structure despite low primary nucleotide and amino acid sequence identity. The structural data and probes we have developed should facilitate studies of the function of CD1a as well as novel investigations of LC.
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PMID:Molecular cloning of CD1a (T6), a human epidermal dendritic cell marker related to class I MHC molecules. 278 20