Effect of intravenous corynebacterium parvum on peripheral-blood effector cells of cancer patients.

The i.v. administration of Corynebacterium parvum (CP) to patients who had recently undergone resection of colorectal tumours was found to have the following effects: 1. Polymorphonuclear leucocyte counts were raised 24 h after CP administration, while both lymphocyte and monocyte counts fell during this period. Polymorph and lymphocyte counts had returned to pre-infusion levels at one week, but monocyte counts were significantly increased at this time. 2. The lymphocyte mitotic response to PHA was reduced during the 24 h after CP infusion. 3 The spontaneous, antibody-induced, and PHA-induced lymphocyte-mediated cytotoxicity against a nucleated target cell fell significantly 3 h after CP infusion, but these functions recovered by 7 days. 4. A rise in serum lysozyme was found 3 and 24 h after CP administration. However, these increased levels were not maintained beyond 24 h.