Objective: To investigate immunomodulatory effects of Astragalus polysaccharides (APS) on the co-culture of peripheral blood mononuclear cells (PBMCs) with HeLa cervical cancer cell line.
Methods: To assess the proliferation of PBMCs, carboxyfluorescein succinimidyl ester (CFSE)-labeled PBMCs were co-cultured with HeLa cells and treated with different concentrations of APS. Supernatants of cell culture were collected for cytokines assay via enzyme-linked immunosorbent assay (ELISA). The impact of APS on the proliferation of PBMCs, induction of regulatory T cells (Tregs), and myeloid-derived suppressor cells (MDSCs) was carried out by flow cytometry.
Results: It was observed that APS could increase the proliferation of PBMCs co-cultured with HeLa cells (P < 0.05). However, APS had no significant effects on the induction of Tregs and MDSCs in the co-culture assay (P > 0.05). Furthermore, ELISA results demonstrated that APS could decrease IL-10 and TGF-β concentration (P < 0.05).
Conclusion: The above-mentioned characteristics showed that APS might be able to modulate immune responses and improve anti-tumor effects through increasing the proliferation of PBMCs and decreasing inhibitory cytokines secretion as critical mediators of immune suppression in the tumor microenvironment.
Keywords: Astragalu; Coculture technique; Cytokine; HeLa cell; Polysaccharide; T-lymphocytes, regulatory; Uterine cervical neoplasm.