Alginate Enhances Memory Properties of Antitumor CD8+ T Cells by Promoting Cellular Antioxidation

Alginate, an FDA-approved natural biomaterial usually used as therapeutic adjuvant, drug carrier and biological scaffold, reportedly assists the immune system to activate cytotoxic T cells in antitumor assays. In this study, we investigated the direct effect of alginate on cytotoxic T cell function. By incubating sorted cytotoxic CD8+ T cells with alginate, we found that this material facilitated the antitumor cytotoxic activities of T cells. Alginate incubation significantly promoted memory properties of CD8+ T cells and elevated the proportion of CD62L+CD44+ central memory T cell (TCM), a less differentiated T cell subset with high immune activity. Mechanistically, alginate reduced reactive oxide species in CD8+ T cells by increasing intracellular glutathione generation, which was critical for conferring T cell with memory properties. Further, we found that guluronic acid, a constituent component (G unit) of alginate, is responsible for inducing glutathione and promoting TCM. Collectively, we reported n...