Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:2.4.2.8 (hypoxanthine-guanine phosphoribosyltransferase)
 2,527 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Different CD15 murine monoclonal antibodies were studied. These antibodies appeared to react specifically with the human myeloid-lineage-derived cell types in both peripheral blood and bone marrow. The antigens recognized by these antibodies were immunoprecipitated from lysates of 125I-labelled neutrophilic PMNs of healthy donors and subsequently analysed by electrophoresis on SDS-polyacrylamide gel and autoradiography. All antibodies precipitated the same membrane polypeptides from the membrane-iodinated PMN lysates: 105 and 150-kDa as most prominent, together with 260-, 230-, 67- and 52-kDa polypeptides. Absorption studies were performed with synthesized carbohydrate molecules. Antibody B4.3 appears to be directed against 3-alpha-fucosyl-N-acetyl-lactosamine (FAL). Competition experiments with 125I-labelled B4.3 demonstrated complete inhibition of binding by B4.3 and three other CD15 antibodies (VIM D5, UJ308, MI/N1), and partial inhibition by three additional antibodies (FMC10, FMC12, FMC13), indicating binding to the same antigenic structure. None of the antibodies reacted with monocytes using the immunofluorescence technique, but after neuraminidase digestion of these cells, positive reactions were obtained with all antibodies. Immunoprecipitation with lysates of both native and neuraminidase-digested monocytes showed no polypeptide bands. Monocytic differentiation of the myeloid cell line HL60 by 12-O-tetradecanoylphorbol-13-acetate (TPA) was accompanied by a decrease in reactivity with the antibodies, which could be reversed by neuraminidase digestion. This indicates that 3-alpha-fucosyl-N-acetyl-lactosamine is masked for the detection with antibodies upon monocytic differentiation by sialylation. Human x mouse myeloid cell hybrids were obtained after fusion of human myeloid cells and the HPRT-deficient murine myeloid cell line WEHI-TG.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Expression of CD15 (FAL) on myeloid cells and chromosomal localization of the gene. 136 94

The inherited human disorders sialidosis and galactosialidosis are the result of deficiencies of glycoprotein-specific alpha-neuraminidase (acylneuraminyl hydrolase, EC 3.2.1.18; sialidase) activity. Two genes were determined to be necessary for expression of neuraminidase by using human-mouse somatic cell hybrids segregating human chromosomes. A panel of mouse RAG-human hybrid cells demonstrated a single-gene requirement for human neuraminidase and allowed assignment of this gene to the (pter----q23) region of chromosome 10. A second panel of mouse thymidine kinase (TK)-deficient LM/TK- -human hybrid cells demonstrated that human neuraminidase activity required both chromosomes 10 and 20 to be present. Analysis of human neuraminidase expression in interspecific hybrid cells or polykaryocytes formed from fusion of mouse RAG (hypoxanthine/guanine phosphoribosyltransferase deficient) or LM/TK- cell lines with human sialidosis or galactosialidosis fibroblasts indicated that the RAG cell line complemented the galactosialidosis defect, but the LM/TK- cell line did not. This eliminates the requirement for this gene in RAG-human hybrid cells and explains the different chromosome requirements of these two hybrid panels. Fusion of LM/TK- cell hybrids lacking chromosome 10 or 20 (phenotype 10+,20- and 10-,20+) and neuraminidase-deficient fibroblasts confirmed by complementation analysis that the sialidosis disorder results from a mutation on chromosome 10, presumably encoding the neuraminidase structural gene. Galactosialidosis is caused by a mutation in a second gene required for neuraminidase expression located on chromosome 20.
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PMID:Sialidosis and galactosialidosis: chromosomal assignment of two genes associated with neuraminidase-deficiency disorders. 308 2