Optimization of Se- and Zn-Enriched Mycelium of Lentinula edodes (Berk.) Pegler as a Dietary Supplement with Immunostimulatory Activity

Mycelial cultures of Lentinula edodes, an edible and medicinal mushroom, have been used in our previous research to obtain selenium-containing immunomodulatory preparations. Our current attempts to obtain a new preparation containing both selenium and zinc, two micronutrients necessary for the functioning of the immune system, extended our interest in the simultaneous accumulation of these elements by mycelia growing in media enriched with selenite and zinc(II) ions. Subsequently, we have studied the effects of new L. edodes mycelium water extracts with different concentrations of selenium and zinc on the activation of T cell fraction in human peripheral blood mononuclear cells (PBMCs). Flow cytometry analysis was used to measure the expression of activation markers on human CD4+ and CD8+ T cells stimulated by anti-CD3 and anti-CD3/CD28 antibodies (Abs). It was demonstrated that statistically significant changes were observed for PD-1 and CD25 antigens on CD8+ T cells. The selenium and zinc content in the examined preparations modified the immunomodulatory activity of mycelial polysaccharides; however, the mechanisms of action of various active ingredients in the mycelial extracts seem to be different.