Abscess induction in beige (bg/bg) mutant mice

Humans with Chediak-Higashi Syndrome (CHS) and several animal species with similar defects have been reported to have increased susceptibility to infection, including abscess formation, associated with granulocyte abnormalities. These defects were investigated by comparing mice of the SB/Le strain, homozygous for the beige mutation, with their heterozygous littermates and with normal BALB/c mice with respect to the ability to form intraabdominal abscesses. Mice were autopsied 7 days after the intraperitoneal inoculation of a mixture of Bacteroides fragilis, Escherichia coli and an abscess-potentiating agent, bran. Although homozygous beige mice formed more numerous abscesses than controls, the total abscess sizes and bacterial contents were not significantly different. Histopathologically, the abscesses resembled those in normal mice. Phagocytic killing assays using granulocytes from beige mice of the SB/Le and C57BL/6J strains showed no significant differences between homozygous beige mice and controls. Within the context of these experiments in which neutrophil function in vivo and in vitro was examined with respect to anaerobic and facultative Gram-negative bacteria, it is concluded that beige mice can respond adequately to an infectious bacterial challenge. The increased susceptibility to an infection seen in various species with CHS-like disease may relate to virulence factors of the infecting organisms and defects in host defences documented by others but not manifest in these experiments.