An immunomodulatory protein, Ling Zhi-8, induced activation and maturation of human monocyte-derived dendritic cells by the NF-kappaB and MAPK pathways.
Ganoderma lucidum, an oriental medicinal mushroom, has been widely used in Asia to promote health and longevity. LZ-8 is a protein derived from the fungus G. lucidum and has immunomodulatory capacities. In this study, we investigated the immune modulatory effects of rLZ-8 on human monocyte-derived DCs. Treatment of DC with rLZ-8 resulted in the enhanced cell-surface expression of CD80, CD86, CD83, and HLA-DR, as well as the enhanced production of IL-12 p40, IL-10, and IL-23, and the capacity for endocytosis was suppressed in DCs. In addition, treatment of DCs with rLZ-8 resulted in an enhanced, naïve T cell-stimulatory capacity and increased, naïve T cell secretion of IFN-gamma and IL-10. Neutralization with antibodies against TLR4 inhibited the rLZ-8-induced production of IL-12 p40 and IL-10 in DCs. rLZ-8 can stimulate TLR4 or TLR4/MD2-transfected HEK293 cells to produce IL-8. These results suggested an important role for TLR4 in signaling DCs upon incubation with rLZ-8. Further study showed that rLZ-8 was able to augment IKK, NF-kappaB activity, and also IkappaBalpha and MAPK phosphorylation. Further, inhibition of NF-kappaB by helenalin prevented the effects of rLZ-8 in the expression of CD80, CD86, CD83, and HLA-DR and production of IL-12 p40 and IL-10 in various degrees. To confirm the in vitro data, we investigated the effect of rLZ-8 further on antigen-specific antibody and cytokine production in BALB/c mice. Immunization with OVA/rLZ-8 showed that the anti-OVA IgG2a, IFN-gamma, and IL-2 were increased significantly compared with OVA alone in BALB/c mice. In conclusion, our experiments demonstrated that rLZ-8 can effectively promote the activation and maturation of immature DCs, preferring a Th1 response, suggesting that rLZ-8 may possess a potential effect in regulating immune responses.
Lin
Yu-Li
YL
Department of Medical Research, Institute of Microbiology and Biochemistry, National Taiwan University Hospital, Taipei, Taiwan, Republic of China.
Liang
Yu-Chih
YC
Tseng
Yu-Shan
YS
Huang
Hsin-Yi
HY
Chou
Shu-Yu
SY
Hseu
Ruey-Shyang
RS
Huang
Ching-Tsan
CT
Chiang
Bor-Luen
BL
D000818:Animals; D015703:Antigens, CD / Q000096:biosynthesis; D016207:Cytokines / Q000096:biosynthesis / Q000276:immunology; D003713:Dendritic Cells / Q000166:cytology / Q000276:immunology / Q000378:metabolism*; D005656:Fungal Proteins / Q000737:chemistry / Q000494:pharmacology*; D005786:Gene Expression Regulation / Q000187:drug effects / Q000276:immunology; D006684:HLA-DR Antigens / Q000096:biosynthesis / Q000276:immunology; D006801:Humans; D007074:Immunoglobulin G / Q000276:immunology / Q000494:pharmacology; D007155:Immunologic Factors / Q000737:chemistry / Q000494:pharmacology*; D020935:MAP Kinase Signaling System / Q000187:drug effects* / Q000502:physiology; D051379:Mice; D008807:Mice, Inbred BALB C; D009000:Monocytes / Q000166:cytology / Q000276:immunology / Q000378:metabolism*; D016328:NF-kappa B / Q000276:immunology / Q000378:metabolism*; D020940:Reishi / Q000737:chemistry; D018417:Th1 Cells / Q000166:cytology / Q000276:immunology / Q000378:metabolism; D051197:Toll-Like Receptor 4 / Q000037:antagonists & inhibitors / Q000276:immunology / Q000378:metabolism
D015703:Antigens, CD; D016207:Cytokines; D005656:Fungal Proteins; D006684:HLA-DR Antigens; D007074:Immunoglobulin G; D007155:Immunologic Factors; D016328:NF-kappa B; C495345:TLR4 protein, human; C493487:Tlr4 protein, mouse; D051197:Toll-Like Receptor 4; C061148:LZ-8 protein, Ganoderma lucidum