[Inhibition of opsonization of E. coli by enzyme-treated gammaglobulin (author's transl)].

The influence of Cohn fraction II, pepsin- and plasmin-treated gammaglobulin on the opsonization of E. coli 0111 was investigated. Normal serum at different dilutions, as well as serum of patients with different forms of antibody deficiency syndromes were tested. No effect was observed by pre-incubation of the bacteria in these gammaglobulins if concentrated or 1:10 diluted serum was used for opsonization. In diluted serum Cohn fraction II potentiated and pepsin-treated gammaglobulin competitively inhibited opsonization, whilst plasmin-treated gammaglobulin potentiated at the low and competitively inhibited at higher dilutions. In serum from patients with antibody-deficiency syndromes, potentiation of opsonization by Cohn fraction II and competitive inhibition by pepsin- and plasmin-treated gammaglobulins was already seen at low serum dilutions.