Increased resistance towards two systemic experimental infections by tetrachlorodecaoxygen anion complex. Possible implications of cellular and humoral immunity.

The tetrachlorodecaoxygen anion complex (TCDO, Oxoferin) given intravenously 1 h after intravenous infection of mice with Candida albicans increased the host's resistance gradually in doses up to 3.1 mumol/kg body weight (b.w.). Above this level, the stimulatory effect decreased, turning to an inhibition at a dose of 18.6 mumol/kg b.w. TCDO. Repeated applications of the optimum single dose had no cumulative effect. In experimental infections with the strictly anaerobic Peptostreptococcus intermedius, TCDO ameliorated the course of the infection not only at a dose of 3.1 mumol/kg b.w. but also at a higher dose of 12.4 mumol/kg b.w. TCDO, which in the Candida sepsis model fell into the range of defence inhibition. A single dose of 3.1 mumol/kg b.w. TCDO also revealed to be the optimum dose to increase the humoral immune response evaluated by the number of immunoglobulin (Ig)M and IgG forming spleen cells after sensitization with sheep red blood cells (SRBC). The same results were obtained, regardless of whether TCDO had been given at the time of immunization or thereafter. The higher single dose of 18.6 mumol/kg b.w. TCDO did not show this effect but was not inhibitory either. Cellular immune reactions evaluated by the footpad swelling test and SRBC as antigen were found considerably enhanced whether TCDO was given once or repeatedly at a dose of 3.1 mumol/kg b.w., whereas single doses of 18.6 mumol/kg or repeated doses of 9.3 mumol/kg induced a certain inhibition.(ABSTRACT TRUNCATED AT 250 WORDS)