A model of intra-abdominal (IA) abscess formation has been developed in mice. Intraperitoneal (i.p.) injection of a mixture of a potentiating agent (autoclaved colonic and caecal contents (ACC), 0.2 mg dry wt/mouse or sterile bran, 1 mg dry wt/mouse), Escherichia coli (1 x 106 colony forming units (cfu)/mouse) and Bacteroides fragilis (5 x 108 cfu/mouse) induced abscesses in 98% of mice inoculated. The abscesses persisted for at least 4 weeks in 60% of inoculated animals, and for 10 weeks in 36%. From 1 to 5 abscesses per mouse were found. Abscess formation was quantified by weighing the dissected abscesses and by culturing bacteria from them. Histologically, the abscesses were characterized by a central region of polymorphonuclear leucocytes, often with a thin mononuclear phagocyte infiltrate surrounding it, and an outer wall of vascularized connective tissue. Fluorescent antibody studies demonstrated that antigens from both bacterial species were distributed throughout the abscess. At the concentrations used, neither ACC nor sterile brain induced formation in the absence of viable bacteria.
|Number of pages||9|
|Journal||British Journal of Experimental Pathology|
|Publication status||Published - 1983|