Penetration of penicillin into human phagocytes containing gonococci

Human phagocytes that had ingested gonococci were incubated with increasing concentrations of penicillin in fresh human serum. Viable counts on phagocyte deposits before and after incubation indicated penicillin penetration at high concentrations but not at lower concentrations which were sufficient to kill extracellular organisms. With lower concentrations significant intracellular survival of gonococci occurred.