Antigen on erythrocytes

Blood typing. There is a close association between the ABO blood antigens on erythrocytes and isoantibodies fomid in plasma. Exceptions are found in patients recently transfused with whole blood. 

Methyldopa can cause hemolytic anemia. At least 20% of patients who receive methyldopa for a year develop a positive Coombs test (antiglobulin test) that is due to autoantibodies directed against the Rh antigen on erythrocytes. The development of a positive Coombs test is not necessarily an indication to stop treatment with methyldopa ... 

Methyldopa can cause hemolytic anemia. At least 20% of patients who receive methyldopa for a year develop a positive Coombs test due to autoantibodies directed against the Rh antigen on erythrocytes. This does not necessitate drug discontinuation 1—5% of these patients will develop a hemolytic anemia that mandates prompt drug discontinuation. The Coombs test may remain positive for as long as a year cffter discontinuation of methyldopa, but the hemolytic anemia usually resolves within a matter of weeks. Severe hemolysis may be attenuated by treatment with glucocorticoids. Rarer adverse effects include leukopenia, thrombocytopenia, red cell aplasia, lupus erythematosus—like syndrome, lichenoid and granulomatous skin eruptions, myocarditis, retroperitoneal fibrosis, pancreatitis, diarrhea, and malabsorption. 

A human serum containing a mono-clonal anti-(blood-group I) antibody has been used to investigate the distribution of blood-group I antigens on erythrocyte membrane components. Different radioactive profiles were revealed by the two radiolabels used with solubilized stroma ( H and In the immuno-precipitates, the predominant I-labelled band had molecular weight 0.9-1.0x10 , whereas the label was associated with a diffuse band (molecular... 

Rho(D) immune globulin is one of the most specific and effective immunosuppressive treatments available. These IgG antibodies have high Rh(D)-specific titers. Administration of Rho(D) immune globulin prevents the response that develops in Rh mothers who were pregnant with an Rh+ fetus and consequently have become sensitized to the D antigen on fetal erythrocytes of the infant. In these Rh mothers, the antibody titers against Rh+ cells will continue to rise after each subsequent... 

Labeled antibody retained ability to bind antigen on the surface of sheep erythrocytes No experimental details authors refer to original B-H paper... 

In one case, hemolysis started after the second dose of rifampicin, and the patient s blood contained rifampi-cin-dependent IgG and IgM antibodies, which caused erythrocyte lysis through an interaction with the I antigen on the erythrocyte surface (35). This antigen is also expressed on renal tubular epithelium and the hemolysis was accompanied by acute renal insufficiency. 

Direct testing of erythrocytes for blood group, Rh, and other antigenic types is used widely in blood banks specific antisera, such as anti-A, anti-C, and anti-Kell, are used to detect such antigens on the erythrocyte surface. 

The pathophysiology of isoimmune hemolysis is the same for all antigens. The differences in severity of disease are due to differences in the expression of the antigen on the surface of the cells, the intrinsic immunogenicity of the antigen, and peculiarities of the immune response of the mother. Destruction of the fetal erythrocytes, which is the central problem, produces several other problems. Fetal anemia imposes an extra burden on the fetal heart to provide adequate oxygen supply to fetal tissues. Anemia stimulates the fetal marrow and extramedullary erythropoiesis in the liver and spleen to replace the destroyed erythrocytes. Extramedullary erythropoiesis destroys hepatocytes and leads to decreased production of serum albumin and decreased oncotic pressure in tire intravascular space. 

Sherman, I. W. and Winogard, E. (1990) Antigens on Plasmodium falciparum infected erythrocytes are not parasite derived. Parasitol. Today 6, 317-320. 

Newbold, C. I. and Marsh, K. (1990) Antigens on the Plasmodium falciparum infected erythrocytes surface are parasite derived. A reply. Parasitol. Today 6,320-322. 

M. pneumoniae adheres to human erythrocytes and to a variety of other cell types, as well as to the ciliated epithelium which is the primary site of infection. The attachment sites on erythrocytes have been shown to be members of the li antigen family with sialic acid a-2,3 linked to galactose [73,74] ... 

Barnwell, J. W., Howard, R. J., and Miller, L. H. (1982). Altered expression of Plasmodium knowlesi variant antigen on the erythrocyte membrane in splenectomized rhesus monkeys.. Immunol. 128, 224-226. 

Haynes, J. D., Dalton, J. 1, Klotz, F. W., McGinnis M. H., Hadley, T. J., Hudson, D. E., and Miller, L. H. (1988). Receptor-like specificity of a Plasmodium knowlesi malarial protein that binds to Duffy antigen ligands on erythrocytes.. Exp. Med. 767,1673-1881. 

Helmby, H., Cavelier, L., Pettersson, U., and Wahlgren, M. (1993). Rosetting Plasmodium falciparum-infected erythrocytes express unique strain-specific antigens on their surface. Infect. Immun. 61,284—288. 

Howard, R. J., Barnwell, J. W., and Kao, V. (1983). Antigenic variation of Plasmodium knowlesi malaria Identification of the variant antigen on infected erythrocytes. Proc. Natl. Acad. Sci. USA 80,4129-4133. 

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