Adjuvant and mitogenic activities of niacine derivatives and their NAD-analogs

The effects of niacine derivatives and their corresponding NAD-analogs on the immune response in vivo and in vitro and the mitogenic activity were investigated. The compounds III, IIIa, IV, V and Va act as adjuvants on the production of circulating antibody to bacterial alpha-amylase in guinea pigs when they were immunized as water-in-oil emulsion. All the compounds at 10-micrograms dose can act as adjuvant on the primary immune response to sheep erythrocytes in vitro. However it was shown that all the compounds had slight or no adjuvant activity on the induction of delayed-type hypersensitivity to ABA-N-acetyl-L-tyrosine. The compounds I, Ia and II were mitogenic in normal mouse spleen cells.