Splenomimetic Effect of Corynebacterium parvum in Fulminant Pneumococcemia

The efficacy of Corynebacterium parvum to stimulate splenic growth and to boost host survival was examined by using adult Sprague-Dawley rats in a highly spleen-sensitive model of fulminant pneumococcemia. Rats were either treated (10 days or 1 hr before or 1 hr after) or not treated with C parvum; were depleted of complement; underwent partial, total, or sham splenic resection; and then were challenged with either a low (2 x 102) or a high (2 x lOS) dose of pneumococci. In the absence of C parvum, survival (percent and duration) was lowest after total splenectomy and was proportional to rem-nant spleen weight after partial splenectomy. Although C parvum treatment sharply in-creased splenic weight, nucleated cell numbers, and survival, the lowered mortality and improved survival time were independent of spleen weight.The rapidly acting, extrasplenic, splenomimetic protective effect of C parvum suggests that this class of immunomodula-tors may be a useful adjunct in managing sepsisassociated with defective or absent splenic function. Despite the use of antibiotics and vaccine prophy-laxis, the asplenic host faces known and unknow