Protective effects of S-sulfonated human gamma globulin against experimental infections in mice.

S-sulfonated gamma globulin (GGS), newly developed as a safe drug for intravenous use, was studied for its protective effects against some experimental infections in mice. Gamma globulin showed a good protective activity against infections due to Streptococcus pneumoniae and Escherichia coli and was moderately active against infections due to Staphylococcus aureus and Pseudomonas aeruginosa. In most cases, the potency of GGS was almost the same as that of original native gamma globulin. The duration of GGS activity in vivo was found to be comparable to that of native gamma globulin and much higher than that of pepsin-digested gamma globulin. In the control of infection due to E. coli, specific antibody was found to play a central role in the antibacterial action of GGS. When GGS was administered in combination with the antibiotics gentamicin and cefazolin for the control of infections due to S. pneumoniae or E. coli, a clear synergistic effect was observed.