COATING IN-VITRO OF ERYTHROCYTES WITH TAMM-HORSFALL PROTEIN

A method is described to coat isolated peripheral blood erythrocytes i n vitro with Tamm-Horsfall Protein (THP, uromodulin). Coating of eryth rocyte with THP was accomplished by incubation of the cells in the pre sence of THP, made monomeric by incubation in a high urea concentratio n. THP-coating of erythrocytes was dependent on the THP-concentration, maximal coating being obtained at a protein concentration greater tha n or equal to 250 mg/ml. The best coating results were obtained if, du ring the co-incubation of erythrocytes with THP, urea was removed whil e the sodium chloride concentration was increased up to a physiologic concentration by means of dialysis. This alteration in chemical condit ions promotes THP-polymerisation. Erythrocytes coated in this way coul d be preserved for at least 5 weeks in preserving solution, making the m an interesting source of testing and control material. Coating of er ythrocytes with THP could also be accomplished under conditions in whi ch THP was preserved in a monomeric form, which suggests that peripher al blood erythrocytes have binding-sites for THP. (C) 1997 Elsevier Sc ience B.V.