Functional Role of a Well Characterized Heteroglycan Isolated from Pleurotus ostreatus Mycelia in Driving Immune Stimulation

Polysaccharides or heteroglycan isolated from fungal species have attained wide recognition for their immune modulating functions. However, there exists a significant relationship in the structural and functional activity of this molecule. In this commentary, we focus on a well characterized heteroglycan isolated from the mycelia of Pleurotus ostreatus which have been shown to drive immune stimulation in tumor bearing mice. The heteroglycan possessed high molecular weight and was primarily composed of glucose, mannose and fucose in a 3:2:1 ratio with major βlinkages in the repeating chain. The molecule also exhibited triple helical conformation in solutions. These immune driving molecules have a significant impact in decreasing the tumor volume in model mice and they are known to play a significant role in the proliferation and activation of lymphocytes in the tumor bearing mice. The physical traits of the heteroglycan were associated with its immune stimulating ability and such compounds can therefore be utilized as adjuvants in immune based therapies.