Adjuvant activity of chitin derivatives in mice and guinea-pigs.

Adjuvant activity of chitin derivatives was examined in guinea-pigs and mice. Among derivatives of chitin tested, 30 and 70% deacetylated chitin (DAC-30 and DAC-70), were active as adjuvants for the circulating-antibody formation to bacterial alpha-amylase and for the induction of delayed-type hypersensitivity to azobenzenearsonate-N-acetyl-L-tyrosine. DAC-70 enhanced the helper T cell function, the generation of alloreactive cytotoxic T lymphocytes, and the activity of natural killer cells in mice, however, it was inactive as mitogen. Other derivatives of chitin showed weaker or no adjuvant activity compared with DAC-70. Carboxymethyl-, hydroxyethyl and dihydroxypropyl-chitin showed weak mitogenic activities on normal spleen cells.