Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0024530 (malaria)
 44,886 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Glycophorin both in solution and inserted into liposomes blocks invasion of erythrocytes by the malaria parasite Plasmodium falciparum. Furthermore, one sugar, N-acetyl-D-glucosamine (GlcNAc), completely blocks invasion of the erythrocyte by this parasite. GlcNAc coupled to bovine serum albumin to prevent the sugar entering infected erythrocytes was at least 100,000 times more effective than GlcNAc alone. Bovine serum albumin coupled to lactose or bovine serum albumin alone had no effect on invasion. These results suggest that the binding of P. falciparum to erythrocytes is lectin-like and is determined by carbohydrates on glycophorin.
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PMID:A lectin-like receptor is involved in invasion of erythrocytes by Plasmodium falciparum. 634 86

Invasion of erythrocytes by malaria merozoites involves attachment of the merozoite membrane at the point of collision with the erythrocytes, then reorientation of the merozoite such that its apex is opposed to the erythrocyte membrane, followed by invaginatin of the erythrocyte membrane and interiorization of the parasite. Specific recognition of erythrocyte surface components by the merozoite has been shown by studies on the specificity of merozoites of different malaria species for a limited range of host-species erythrocytes, for erythrocytes of particular maturity, and for erythrocytes possessing particular blood-group determinants. Different malaria species capable of invading erythrocytes of the same host also exhibit differences in specificity for components on enzyme-treated erythrocytes. The attachment phase of merozoite invasion has been isolated from subsequent steps by treatment of merozoites with cytochalasin B -- they then attach to but do not invade susceptible erythrocytes. There is now evidence for other differences between initial attachment steps and subsequent invasion steps form studies on merozoite treatments in vitro which affect invasion but not attachment. It has also been shown that addition of N-acetyl-D-glucosamine to cultures of Plasmodium falciparum inhibits merozoite invasion. Elucidation of the sequence and nature of molecular interactions of merozoite and erythrocyte membrane molecules during invasion will be based on the fundamental ultrastructural observations and on the specificity of attachment and invasion steps already described.
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PMID:Invasion of erythrocytes by malaria merozoites: evidence for specific receptors involved in attachment and entry. 702 Oct 86

Mannans and its related compounds decelerated human (Hu) red blood cell (RBC)-clearance in severe combined immunodeficiency (SCID) mice by inhibiting erythro-phagocytosis of macrophages. Chimeric SCID mice for Hu-RBC which are generated by repeated transfusions with mature Hu-RBCs are described recently as a model for Plasmodium falciparum infection, though the Hu-RBC clearance in the mice at present is very rapid and the parasitemia in the mice is only erratic. Here, we aimed to study the method to decelerate Hu-RBC clearance in SCID mice, to establish a suitable mouse model for malaria parasites. Yeast and Candida mannans as well as lactoferrin, a glycoprotein containing both oligomannoside- and N-acetyllactosamine-type glycans, decelerated Hu-RBC clearance, but instead other saccharides such as carboxymethyl chitin, N-acetylglucosamine, and D-glucose did not. Yeast mannan and lactoferrin interfered significantly with in vitro Hu-RBC-phagocytosis which was also inhibited by mannopentaose and mannotoriose. D-mannose exhibited a moderate inhibitory activity. N-acetyl-D-glucosamine, however, showed only a slight inhibitory activity, but D-glucose had no inhibitory activity on Hu-RBC phagocytosis. These results may postulate that Hu-RBC clearance in SCID mouse might be mediated by receptor-ligand binding by a macrophage lectin like receptor with mannose specificity.
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PMID:Mannan decelerates the clearance of human red blood cells in SCID mouse. 950 21