The effects of RU 41. 740, a glycoprotein immunomodulating agent derived from Klebsiella pneumoniae, on intra-abdominal abscess formation in mice

Abstract

Summary. The prophylactic and therapeutic efficacies of the immunomodulating agent RU 41 .740 (a glycoprotein extract from Klebsiella pneumoniae) were studied in a murine model of intra-abdominal abscess formation with Bacteroides fragilis, Escherichia coli, and bran as an abscess-potentiating agent. Parenteral injection of RU 41 .740, either before or after injection of an abscess-inducing mixture (AIM), was associated with significantly diminished incidence and size of abscesses. Abscess incidence and size were significantly decreased by oral administration of RU 41 .740 after, but not before, AIM injection. Abscess formation and resolution are the results of complex interactions of host defence mechanisms with bacteria and potentiating agent, and RU 41 .740 has been shown previously to activate both macrophage and neutrophil function. These results indicate that activation of non-specific defences may protect against abscess development in chronic sepsis.

Inflammatory processes in a murine model of intra-abdominal abscess formation

“…In both clinical and experimental settings, protocols have been developed that attempt to interfere with various aspects of the pathogenic process. These include appropriate surgical procedures [2], antibiotic usage [3], prophylactic use of both anticoagulants [4] and fibrinolytic compounds [5] directed at the involvement of fibrin in abscess formation, and various nonspecific immunomodulators such as muramyl dipeptide [6] and RU 41.740 [7]. Although several of these are useful in reducing abscess formation, the improvement is often only partial, their effects are not sufficiently local, or they prevent abscess formation but not systemic infection.…”