Antibodies to carbohydrate epitopes are often of the IgM isotype and require multiple binding for sufficient avidity. Therefore clusters of epitopes are preferred antigenic sites in these cases. We have examined the type of clusters recognized by two anti-Thomsen-Friedenreich (TF, core-1, CD176) IgM antibodies, NM-TF1 and NM-TF2, using several different sets of TF-carrying synthetic glycoconjugates in ELISA experiments.
View Article and Find Full Text PDFInt Immunopharmacol
November 2010
Glycophorin A (GPA, CD235a) is a major membrane glycoprotein and marker of cells of the erythroid lineage. It is also the target of Plasmodium falciparum and of influenza virus. We describe a novel series of 10 antibodies towards GPA, recognizing four extra- and intracellular peptide epitopes of this molecule (defined by epitope mapping) and one mixed peptide/carbohydrate epitope.
View Article and Find Full Text PDFThe expression of the histo-blood group carbohydrate structures T-nouvelle (Tn, CD175), sialylated Tn (CD175s) and the Thomsen-Friedenreich disaccharide (TF, CD176) on human leukemia cell lines was analyzed by their reactivity with specific monoclonal antibodies in flow cytometry, immunohistology and immunoprecipitation. Expression of sialylated CD176 was evaluated by comparative immunostaining with anti-CD176 antibodies before and after sialidase treatment. While only few cell lines expressed unmasked CD176, sialylated CD176 was present on all hematopoietic cell lines and native lymphocytes examined.
View Article and Find Full Text PDFIn a search for novel immunostimulating substances we detected that culture supernatants of the gram-positive phytopathogenic bacterium, Rhodococcus fascians, were able to induce cytokine release (TNF(alpha)) from mouse peritoneal macrophages. Monoclonal antibodies were generated against the active principle, and were employed for its isolation and partial characterization as a high molecular (MW>100 kDa) glycoprotein. In addition, methods practicable for its biotechnological preparation and several ELISA variants for its determination were developed.
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