PROTECTIVE ACTIVITIES OF THE COMMERCIALLY AVAILABLE HUMAN IMMUNOGLOBULIN AS WELL AS A FRESH HUMAN SERUM AGAINST VARIOUS OPPORTUNISTIC INFECTIONS

Abstract

Agglutinating and opsonic activities of the commercially available human immunoglobulin as well as a healthy human volunteer serum against various bacteria were examined. The opsonin titers of both serum materials against most of the rare resident bacteria were found to be almost same as their agglutinin titers, suggesting that opsonins in the serum materials were specific agglutinating antibodies. Therefore, the protective activities of the serum materials against various opportunistic pathogens could be judged by their contents of specific antibodies. But it was also observed that the opsonin titers against the major resident bacteria, such as Escherichia coli, Streptococcus faecalis and Lactobacillus spp. were higher than the agglutinin titers, suggest-ing that the circulating antibodies specific for major resident bacteria were small, because of the frequent consumptions by the invaded bacteria into cir-culation.