[The beta-carotene stimulation of cellular immunity reactions in mice]

The immunomodulating properties of synthetic beta-carotene were studied in C57Bl/6 and BALB/c mice using the tests of proliferative, cytotoxic and suppressor activity, and evaluating the adhesive capacity of macrophage lineage cells. Long-term feeding of C57Bl/6 mice with beta-carotene microgranules (0.1-0.5 mg of active substance per mouse) led to enhanced T cell proliferative response to ConA, which lasted for 15-45 days. Administration of beta-carotene oil solution to BALB/c mice previously immunized with alloantigens (0.17-0.34 mg of beta-carotene per mouse) enhanced T-cell cytotoxicity against L-929 and YAC-1 cells and macrophage cytotoxicity against L-929 cells. The treatment also reduced T-suppressor activity as shown in the assays of inhibition of the lymphocyte blast transformation reaction and mixed lymphocyte culture. The treatment with both preparations of beta-carotene enhanced the adhesive properties of macrophages and related cells, and induced the increased production of oxygen active radicals by these cells.