Erythrocyte-membrane Glycoproteins

Hematologic A 64-year-old man, who had a history of allergy to penicillin, tolerated cefuroxime, metronidazole and gentamicin without incident, but developed severe intravascular hemolysis after being given meropenem it resolved on withdrawal of meropenem [5" ]. The authors suggested that this reaction had been due to a haptenic reaction with an erythrocyte membrane glycoprotein and formation of IgG or IgM antibodies however, they did not present any evidence of this mechanism in relation to their case. 

A comparative immunochemical study of human erythrocyte membrane glycoprotein which uses two different extraction procedures has been reported. Each preparation contained receptors for influenza virus and was composed of protein (50%) and carbohydrate (30—40%). 

Erythrocyte-membrane Glycoproteins.—Human erythrocyte-membrane glycoprotein has been modified to a tryptic glycopeptide, which was desialylized by mild acid treatment. The non-reducing, terminal D-galactosyl residue of the glycopeptide was labelled by enzymic oxidation and reduction with sodium borotritide. 

Specific applications of carbon-13 n.m.r. spectroscopy to the glycophorins, an important family of glycoproteins present in the human erythrocyte membrane, are discussed by K. Dill (Clemson), who demonstrates the value of C-n.m.r. spectra for the structural mapping of glycoproteins. 

A feasible way of introducing acid-stable linkages into carbohydrates is N-deacetylation. This can be achieved with hydrazine.59,70,71 The use of sodium hydroxide-sodium benzenethioxide in aqueous dimethyl sulfoxide for this purpose has also been described72 The difference in the acid hydrolysis of N-acetylhexosamine-con-taining carbohydrates before and after N-deacetylation was used in the study of complex glycoprotein saccharides from human erythrocyte membranes.73-75 Methylation analysis of the glycopeptides prepared... 

A similar mechanism is apparently responsible for removing old erythrocytes from the mammalian bloodstream. Newly synthesized erythrocytes have several membrane glycoproteins with oligosaccharide chains that end in NeuSAc. When the sialic acid residues are removed by withdrawing a sample of blood, treating it with sialidase in vitro, and reintroducing it into the circulation, the treated erythrocytes disappear from the bloodstream within a few hours those with intact oligosaccharides (erythrocytes withdrawn and reintroduced without sialidase treatment) continue to circulate for days. 

Newman, R. A. and Uhlenbruck, G. G. 1977. Investigation into the occurrence and structure of lectin receptors on human and bovine erythrocyte, milk-fat globule and lymphocyte plasma-membrane glycoproteins. Eur. J. Biochem. 76, 149-155. 

Sendai virus, like other myxo- and paramyxovirus, has surface glycoprotein spikes which adsorb to specific receptors on erythrocytes of most mammalian and fowl species and cause hemagglutination. The receptors on erythrocyte membranes contain neuraminic acid, as indicated by the fact that they are destroyed by neuraminidase. Haywood (3 ) demonstrated that liposomes containing gangliosides could inhibit the agglutination of erythro-... 

Lectin-reactive glycoproteins of the erythrocyte membrane have been studied extensively. Of these, the major sialoglycoprotein has... 

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