Activation of selective transcription factors and cytokines by water-soluble extract from Lentinus lepideus.
We isolated a water-soluble extract, PG101, from cultured mycelia of Lentinus lepideus. Treatment of human peripheral blood mononuclear cells (PBMCs) with PG101 increased levels of TNF-alpha, IL-1beta, IL-10, and IL-12 by 100- to 1000-fold, whereas GM-CSF and IL-18 were activated by an order of magnitude. On the contrary, IFN-gamma and IL-4 were not affected. The response to PG101 occurred in a dose- and time-dependent manner. From the human PBMCs treated with PG101, TNF-alpha was a first cytokine to be activated, detectable at 2 hr post-treatment followed by IL-1beta at 6 hr post-treatment. IL-12 and IL-10 were the next to follow. GM-CSF and IL-18 both showed significant increases 24 hr after treatment. When PBMCs were sorted into various cell types, monocyte/macrophages, but not T and B cells, were the major target cell type responsive to PG101. Consistent with this result, the profile of cytokine expression upon PG101 treatment was comparable between PBMCs and a human promonocytic cell line (U937), whereas cell lines of T cell and myeloid origins did not respond to PG101. Data from a transient transfection assay involving specific reporter plasmids indicated that cellular transcription factor such as NF-kappaB, but not AP-1, was highly activated by PG101. Results from a gel retardation assay and the experiment involving a specific NF-kappaB inhibitor confirmed the involvement of NF-kappaB. Despite its significant biological effect on various cytokines, PG101 remained nontoxic in both rats and PBMCs even at a biological concentration approximately 20 times greater. PG101 demonstrates great potential as a therapeutic immune modulator.
Jin
Mirim
M
PanGenomics Co Ltd, Biotechnology Incubating Center, Seoul 151-742, Korea.
Jung
Hyung Jin
HJ
Choi
Jeong June
JJ
Jeon
Hyang
H
Oh
Jin Hwan
JH
Kim
Bongcheol
B
Shin
Sung Seup
SS
Lee
Jong Kyu
JK
Yoon
Keejung
K
Kim
Sunyoung
S
D000818:Animals; D016207:Cytokines / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D024202:Electrophoretic Mobility Shift Assay; D017930:Genes, Reporter / Q000235:genetics; D006801:Humans; D020074:Lentinula / Q000737:chemistry*; D007963:Leukocytes, Mononuclear / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D016328:NF-kappa B / Q000037:antagonists & inhibitors / Q000378:metabolism*; D010936:Plant Extracts / Q000494:pharmacology* / Q000633:toxicity; D010957:Plasmids / Q000235:genetics; D011392:Proline / Q000031:analogs & derivatives* / Q000494:pharmacology; D051381:Rats; D012995:Solubility; D013859:Thiocarbamates / Q000494:pharmacology; D013997:Time Factors; D014162:Transfection; D014407:Tumor Cells, Cultured
D016207:Cytokines; D016328:NF-kappa B; D010936:Plant Extracts; D013859:Thiocarbamates; C066229:prolinedithiocarbamate; D011392:Proline