Immunomodulatory effects of extract ofGanoderma lucidumbasidiocarps cultivated on alternative substrate

Abstract

24Background: Ganoderma lucidum is a medicinal mushroom exhibiting numerous health 25 benefits primarily based on strong immunostimulatory effects. The aim of the study was 26 to investigate if there were differences in effects of extracts of commercially (GC) and 27 alternatively (wheat straw) (GA) cultivated G. lucidum basidiocarps on properties of 28 peritoneal macrophages (PM) and monocyte-derived dendritic cells (MoDCs). 29 Methods: Differences in immunomodulatory effects of GC/GA extracts were studied. 30 Viability of treated PMs, their adhesive and phagocytic capability and capacity to produce 31 reactive oxigen species (ROS) and NO was tested. Immature MoDCs generated from 32 human monocytes were treated with poly I:C (10.0 µg/ml) and loxoribine (34.0 µg/ml), a 33 selective TLR3 and TLR7 agonists, respectively, and with/without GC/GA extract (100.0 34 µg/ml). The effect of each combination on phenotypic properties, cytokines production by 35 MoDCs, and their proliferation and Th polarizing capacity was studied. 36 Results: GA extract stronger stimulated metabolic and phagocytic activity of PMs, their 37 adhesion capability and ability to produce ROS and NO compared to GC. Both tested 38 extracts significantly increased allostimulatory and Th1 polarization capacity of 39 simultaneous TLR3 and TLR7-activated MoDCs, but GA extract was more effective. 40 Discussion: The extract of alternatively cultivated G. lucidum basidiocarps increased 41 production of ROS and NO by TLR4 stimulated PMs and up-regulated production of 42 certain cytokines as well as allostimulatory and Th1 polarization capacity of MoDCs. GA 43 extract could be a potent immunostimulatory agent for activation of MoDCs with 44 simultaneous engagement of TLRs that seems to be a promising strategy for preparation 45 of DC-based anti-tumor vaccines. 46 47