The T-lymphocyte co-receptors of MHC glycoproteins CD4 and CD8 are known to be associated with the protein tyrosine kinase Lck via cysteine-containing sequences in the cytoplasmic domains of CD4 and CD8 and in the N-terminal domain of Lck. Here we demonstrate that a fraction of CD4 and CD8 molecules are associated with very large, detergent-resistant complexes containing several glycosylphosphatidylinositol-anchored proteins, (glyco)lipids, and protein tyrosine kinases Lck and Fyn but apparently no other major transmembrane proteins. Association of Lck and Fyn with these large complexes is, in contrast to simple CD4/CD8-Lck complexes, not sensitive to alkylation with iodoacetamide. These large complexes therefore represent an alternative way of association of CD4 and CD8 with the protein tyrosine kinases, which may play a role in signaling through these receptors.

• MeSH
• antigeny CD4 analýza   MeSH
• antigeny CD8 analýza   MeSH
• buněčná membrána chemie   MeSH
• glykosylfosfatidylinositoly MeSH
• lidé MeSH
• lymfocyty chemie   MeSH
• nádorové proteiny * MeSH
• tyrosinkinasa p56(lck), specifická pro lymfocyty MeSH
• tyrosinkinasy analýza   klasifikace   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antigeny CD4 MeSH
• antigeny CD8 MeSH
• FRK protein, human MeSH Prohlížeč
• glykosylfosfatidylinositoly MeSH
• nádorové proteiny * MeSH
• tyrosinkinasa p56(lck), specifická pro lymfocyty MeSH
• tyrosinkinasy MeSH

The glycosyl phosphatidylinositol (GPI)-linked antigen recognized by monoclonal antibody (mAb) MEM-102 is expressed on all peripheral blood lymphocytes, both resting and activated. Its properties are very similar to a previously described activation antigen, Blast-1. The amino acid sequence deduced from the structure of cloned cDNA is identical to that of the Blast-1 antigen except for a single amino acid residue. There are several other minor differences in the nucleotide sequence of the Blast-1 and MEM-102 cDNAs that do not affect the predicted structure of the polypeptide product. The amino acid sequence of the first 15 N-terminal residues of the antigen purified from Raji cells is found in the deduced sequence close to the presumed boundary between the leader peptide and mature polypeptide. Properties of the recombinant product expressed in COS cells are similar to the antigen isolated from peripheral blood mononuclear cells (PBMNCs) or B-and T-cells lines. The antigen purified on immobilized mAb MEM-102 is recognized by all six known CD48 mAbs under western blotting conditions. COS cells transfected with MEM-102 cDNA react with all the CD48 mAbs. It is concluded that mAb MEM-102 is directed against the as yet poorly characterized antigen CD48, which is therefore structurally closely related to Blast-1. Several possibilities are discussed that might account for the apparent discrepancy between the broad pan-leucocyte expression of the between the broad pan-leucocyte expression of the MEM-102/CD48 antigen and much more restricted expression of the epitope recognized by the previously described mAb defining the Blast-1 antigen.

• MeSH
• antigen CD48 MeSH
• antigeny povrchové chemie   MeSH
• CD antigeny chemie   MeSH
• diferenciační antigeny chemie   MeSH
• klonování DNA MeSH
• leukocyty mononukleární imunologie   MeSH
• lidé MeSH
• membránové glykoproteiny chemie   MeSH
• molekulární sekvence - údaje MeSH
• monoklonální protilátky MeSH
• sekvence aminokyselin MeSH
• sekvence nukleotidů MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• antigen CD48 MeSH
• antigeny povrchové MeSH
• CD antigeny MeSH
• CD48 protein, human MeSH Prohlížeč
• diferenciační antigeny MeSH
• membránové glykoproteiny MeSH
• monoklonální protilátky MeSH

CD53 is an N-glycosylated pan-leucocyte antigen of 35-42,000 Mr. The sequence of the CD53 polypeptide deduced from a cDNA clone is 219 amino acids in length. It appears to lack a conventional leader sequence because the deduced NH2-terminal amino acid sequence is very similar to the rat MRC OX-44 and human CD37 antigens. The CD53 molecule is likely to consist of four transmembrane regions and a major extracellular hydrophilic loop containing two potential N-glycosylation sites. It is suggested that the CD53 glycoprotein is the true human homologue of the rat OX-44 antigen, rather than the CD37 antigen of more restricted expression and lower NH2-terminal sequence similarity to OX-44.

• MeSH
• antigeny CD53 MeSH
• antigeny nádorové * MeSH
• CD antigeny * MeSH
• diferenciační antigeny T-lymfocytů genetika   MeSH
• diferenciační antigeny genetika   MeSH
• DNA analýza   MeSH
• glykoproteiny genetika   MeSH
• klonování DNA MeSH
• krysa rodu Rattus MeSH
• lidé MeSH
• molekulární sekvence - údaje MeSH
• northern blotting MeSH
• RNA analýza   MeSH
• sekvence aminokyselin MeSH
• sekvence nukleotidů MeSH
• sekvenční homologie nukleových kyselin MeSH
• Southernův blotting MeSH
• tetraspaniny MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• srovnávací studie MeSH
• Názvy látek
• antigeny CD53 MeSH
• antigeny nádorové * MeSH
• CD antigeny * MeSH
• CD37 protein, human MeSH Prohlížeč
• Cd37 protein, rat MeSH Prohlížeč
• CD53 protein, human MeSH Prohlížeč
• Cd53 protein, rat MeSH Prohlížeč
• diferenciační antigeny T-lymfocytů MeSH
• diferenciační antigeny MeSH
• DNA MeSH
• glykoproteiny MeSH
• RNA MeSH
• tetraspaniny MeSH

Most developmentally regulated epitopes identified on embryonal carcinoma cells and murine preimplantation embryos are associated with a glycoprotein-bound large glycan called embryoglycan. To prepare monoclonal antibodies recognizing other, less immunogenic stage-specific embryonic epitopes, we used embryoglycan-negative embryonal carcinoma cells P19XT.1.1 as immunogen. One monoclonal antibody prepared by this strategy was found to react specifically with mouse embryonal carcinoma and embryo-derived stem cell lines. The target epitope, TEC-4, was found to be expressed on eggs and two-cell embryos but was undetectable on later stages of mouse embryos and adult mouse tissues. NaDodSO4/PAGE of immunoaffinity-isolated antigen revealed that TEC-4 epitope is associated with glycoproteins of apparent Mr 120,000 and 240,000. The epitope was resistant to oxidation by sodium periodate and to digestion by endoglycosidase F but was sensitive to treatment with protein-denaturing agents and proteases, which suggested that the epitope is located in the protein moiety of the molecule. In the course of retinoic acid-induced differentiation of embryonal carcinoma cells the epitope disappeared before the onset of morphological differentiation. The combined data indicate that TEC-4 is an unusual stage-specific embryonic antigen that may be amenable to direct genetic analysis.

• MeSH
• antigen Lewis X MeSH
• antigeny nádorové izolace a purifikace   MeSH
• buněčná diferenciace účinky léků   MeSH
• buněčné linie MeSH
• cytotoxicita imunologická MeSH
• exprese genu MeSH
• fluorescenční protilátková technika MeSH
• glykolipidy genetika   izolace a purifikace   MeSH
• molekulová hmotnost MeSH
• monoklonální protilátky * MeSH
• myši MeSH
• nádorové biomarkery analýza   MeSH
• nádorové buňky kultivované cytologie   účinky léků   imunologie   MeSH
• polysacharidy genetika   MeSH
• teratom imunologie   MeSH
• tretinoin farmakologie   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• antigen Lewis X MeSH
• antigeny nádorové MeSH
• embryoglycan MeSH Prohlížeč
• glykolipidy MeSH
• monoklonální protilátky * MeSH
• nádorové biomarkery MeSH
• polysacharidy MeSH
• tretinoin MeSH