Abstract: | Guinea pigs were infected intramuscularly with different doses of S. aureus. At different periods after infection the chemiluminescence (CL) of the primary focus in the animals infected with 10(10) colony-forming units (CFU) of S. aureus (abscess formation on day 3, mortality rate equal to 70%) was poor and increased only on days 6-9; in animals injected with 10(9) CFU (abscess formation on day 6, mortality rate equal to 16%) the CL increased on day 3 and lasted till day 20; in the animals infected with 10(8) CFU (the appearance of infiltration, no mortality) the reaction increased on day 1, then decreased; and in those infected with 10(2) CFU (no local manifestations of the process) the reaction was low at all periods. CL peak was recorded early mainly due to the neutrophil reaction, while a later CL peak (in cases of the favorable outcome of the infection) was explained by the macrophagal reaction. Thus, for the favorable outcome of the infection (in the presence of inflammation) the early increase of the CL of neutrophils migrating to the focus is characteristic, while the resolution of the local process is manifested by CL decrease and the prevalence of the macrophagal component of the reaction. |