Immunity to antigenically related salmonellae: effects of humoral factors on the bactericidal activity of normal and immune peritoneal exudate cells

Activation of peritoneal macrophages by concanavalin A or Mycobacterium bovis BCG for fungicidal activity against Blastomyces dermatitidis and effect of specific antibody and complement

With a new short-term assay, where the reduction of CFUs in the inoculum could be measured, we investigated the killing of the dimorphic fungal pathogen Blastomyces dermatitidis in its yeast phase by murine peritoneal macrophages. Peritoneal macrophages from concanavalin A- or Mycobacterium bovis BCG-treated mice, but not resident or thioglycolate-elicited macrophages, significantly reduced the CFUs of B. dermatitidis in the inoculum. The activation of peritoneal macrophages for fungicidal activity by concanavalin A treatment was shown to be dose dependent and transient, i.e., absent after 72 h. These results indicate that it is possible for murine peritoneal macrophages to kill B. dermatitidis in vitro. The addition of specific antibody or complement or both did not enhance the killing of B. dermatitidis by these nonspecifically activated macrophages.

Effect of dietary essential amino acid limitations upon native levels of murine serum immunoglobulins, transferrin, and complement

Effects of dietary essential amino acid (leucine, isoleucine, valine, or lysine) limitations upon the native levels of serum immunoglobulin G (IgG), IgM, and IgA, as well as transferrin, the third component of complement (C3), and albumin were determined in CF1 mice by the radial immunodiffusion technique. Male mice fed the control diet and the isoleucine- or valine-limited diets exhibited lower levels of serum IgG than the female mice fed the same diets. Levels of IgG in female experimental mice were not significantly different than those in female control mice. Serum IgM levels in male or female mice fed the experimental diets were higher than those in the control mice. Except for the mice fed the isoleucine-limited diet, serum IgA levels were higher in male and female mice fed the experimental diets than in mice fed the control diet. Serum transferrin levels were not significantly different in mice fed the experimental diets when compared with mice fed the control diet. However, the levels of transferrin found in the peritoneal exudates were lower in mice fed the isoleucine- or lysine-limited diets than in mice fed the control diet. In mice fed the isoleucine- and lysine-limited diets, the levels of serum C3 were significantly lower than those in control mice. These results indicate that the native levels of serum immunoglobulins are increased in some instances and that the levels of serum C3 and the transferrin in the peritoneal fluid are significantly decreased in certain dietary groups of mice.