Effects of Corynebacterium parvum on cellular immunity of cancer patients, assayed sequentially over 63 days

The immunologic effects of Corynebacterium parvum (2 mg/M2) infused at three-week intervals were determined by 19 sequential assays in each of nine patients with metastatic malignancy. Peripheral blood immunologic profiles were followed for 63 days. No statistical significant changes (P greater than 0.05) occurred in total white cell, lymphocyte, or monocyte counts. Subpopulation assays demonstrated significant increases in E rosetting cells but not in sIg-bearing cells; there was a corresponding significant decrease in null-cell proportions. Killer cell lymphocytotoxicity was measured by 51Cr release from Chang target cells. Significant increases were observed one week after immunization and were maintained on subsequent immunizations. NK- and K-cell cytotoxicity were particularly augmented; T-cell cytotoxicity expressed as lytic units/ml was significantly increased on fewer assay occasions. Killer cell function has a possible in vivo antitumor role and methods of boosting and maintaining the activity deserve consideration. A three-week immunization schedule with C. parvum is supported by the current work and is the basis of a randomized adjuvant immunotherapy study of patients with malignant melanoma.