Haematologia 6. (1972)
1972 / 3. szám - Puskás, É. - Ferencz, É. G. - Szelényi, J. G. - Hasitz, M. - Medgyesi, G. A. - Gergely, J.: Non-specific attachment of IgG to erythrocytes
276 Éva Puskás et al. : Non-specific attachment of IgG to erythrocytes described earlier [6, 7]. In a typical experiment, equal volumes of packed erythrocytes and IgG solution (1 mg/ml) were incubated at 37°C for 60 min. After incubation, the red blood cells were washed three times with isotonic sucrose solution. After centrifugation the red blood cell button was mixed with an equal volume of isotonic NaCl solution and was centrifuged. For studying the influence of IgG and IgG fragments on the release of nonspecifically fixed IgG molecules, 1 mg/ml solution of 131I labelled IgG was incubated at 37°C for 60 min with equal amounts of packed erythrocytes. After centrifugation the red cell button was washed three times with isotonic sucrose solution and the red blood cells were suspensed in equal amounts of the following solutions: isotonic saline, isotonic saline containing either Fab or F(ab’)2 or Fc fragments or IgG molecules at 1 mg/ml concentration. After a 30 min incubation period the suspension was centrifuged and the number of fixed IgG molecules was estimated on the basis of the specific activity of labelled IgG and erythrocyte number. The IgG preparations were labelled with 131I using Bocci’s chloramine-T method [17]. The erythrocytes were labelled with Na2H32PO( [18]. Preparation of erythrocyte membrane was performed according to Parker and Hoffmann [19]. To obtain anti-membrane antibodies, rabbits were injected with membrane preparations. Immunoelectrophoretic investigation of erythrocyte membrane preparations was performed according to Demus and Mehl [20]. Results Influence of IgG and IgG fragments on the release of non-specifically fixed IgG. The tissue binding property of IgG molecules is a function of their Fc part. One may suppose that the non-specific fixation of IgG molecules on the surface Fig. 1. Relative amount of IgG remaining fixed on erythrocytes after incubation of cells previously coated with iodine labelled IgG in media containing I mg/ml IgG or different IgG fragments in physiological saline Haematologia 6, 1972