Binding parameters of defined immune complexes to rat basophilic leukaemia (RBL) cells

The binding parameters of chemically-defined immune complexes composed of rat IgGa-anti-human serum albumin (HSA) to rat basophilic leukaemia cells were analysed. It was demonstrated that the uptake of various sized immune complexes is time-, temperature- and pH-dependent. A higher binding rate was observed with more Fc portions available in the immune complex. A comparison of the binding rate for immune complexes with that of heat aggregates shows that immune complexes bind with greater affinity to the cells.