A single peritoneal injection of cell wall extract from Lactobacillus casei (LCWE) in mice can induce acute cardiac angitis mimicking that observed in patients with Kawasaki disease (KD) . Several proinflammatory cytokines play an essential role in the generation of vasculitis in KD and mice. Many reports show that highdose administration of human immunoglobulins (IVIG) prevents progressing coronary aneurysms in KD. IVIG contains the antibodies against some proinflammatory cytokines, to neutralize their activity. However, the central mechanism of therapeutic efficacy remains unclear.
The present paper describes the suppressive effect of dexamethasone and mouse IgG (mIgG) on LCWE-induced vasculitis in mice. The mIgG was sterilely purified from sera of retired mice. A one shot intravenous treatment of mIgG (1 mg/lg of body weight) with prior (4 hr before) or simultaneous injection of LCWE significantly suppressed the generation of cardioangitis in mice. Anti-IL-1α antibody could not be detected in the mIgG used in this study. The administration of dexamethasone (4 μg/1 g of body weight) with LCWE could also inhibit the generation of vasculitis. We discuss the suppressive effect of mIgG and dexamethasone on LCWE induced cardioangitis in mice.