title: Immunopotentiation of Pleurotus eryngii (DC. ex Fr.) Quel.
abstract: BACKGROUND
  Pleurotus eryngii (DC. ex Fr.) Quel has been collected from the wild, cultivated and used in traditional medicines to treat various disorders and diseases since antiquity. In traditional Chinese medicine, the powdered fruiting bodies of Pleurotus eryngii were used for immunostimulation, skin-care, wound-healing, cancer and lumbago treatment. In the current study, we investigated the antiproliferative activity of Pleurotus eryngii powder on A549, BGC-823, HepG2 and HGC-27 cancer cells and its immunomodulating activity on macrophage, RAW 264.7 cells based on its active compound.
  
  
  METHODS
  A novel bioactive protein (PEP) was extracted from Pleurotus eryngii fruiting bodies powder and purified on DEAE-52, CM-52 and Superdex 75 column chromatographies using an ÄKTA purifier. Its cytotoxicity on A549, BGC-823, HepG2, HGC-27 and RAW 267.4 cell lines was then evaluated using MTT, alamar blue (AB), trypan blue (TB), neutral red (NR), lactate dehydrogenase (LDH), Annexin V FITC/PI and morphological change assays. Moreover, lysosomal enzyme activity, pinocytosis, nitric oxide (NO) and hydrogen peroxide (H₂O₂) production assays were used to examine immunomostimulatory activity of PEP on RAW 267.4 cells.
  
  
  RESULTS
  Based on high performance gel permeation chromatography (HPGPC), Fourier transform infrared (FT-IR) and nuclear magnetic resonance (NMR) analyses, the isolated protein (PEP) had a molecular weight of 63 kDa, a secondary (α-helical) structure and was mainly composed of arginine, serine and glycine. PEP significantly (P<0.05) inhibited A549, BGC-823, HepG2 and HGC-27 tumor cells proliferation dose-dependently with an IC₅₀ range of 36.5 ± 0.84 to 229.0 ± 1.24 µg/ml. Contrarily, PEP stimulated the proliferation of macrophages.
  
  
  CONCLUSIONS
  Pleurotus eryngii fruiting bodies powder has a potential application as a natural antitumor agent with immunomodulatory activity, proposedly, by targeting the lysosomes of cancerous cells and stimulating macrophage-mediated immune responses.
authors.affiliation: College of Food Science and Technology, Nanjing Agricultural University, No. 1 Weigang Road, Nanjing 210095, PR China; Department of Dairy and Food Science and Technology, Egerton University, Egerton 536, Kenya.
authors.forename: Alfred Mugambi
authors.initials: AM
authors.lastname: Mariga
authors.affiliation: College of Food Science and Technology, Nanjing Agricultural University, No. 1 Weigang Road, Nanjing 210095, PR China.
authors.forename: Fei
authors.initials: F
authors.lastname: Pei
authors.affiliation: College of Food Science and Engineering, Nanjing University of Finance and Economics, No. 3 Wenyuan Road, Nanjing 210046, PR China.
authors.forename: Wen-jian
authors.initials: WJ
authors.lastname: Yang
authors.affiliation: College of Food Science and Technology, Nanjing Agricultural University, No. 1 Weigang Road, Nanjing 210095, PR China.
authors.forename: Li-yan
authors.initials: LY
authors.lastname: Zhao
authors.affiliation: College of Food Science and Technology, Nanjing Agricultural University, No. 1 Weigang Road, Nanjing 210095, PR China.
authors.forename: Ya-ni
authors.initials: YN
authors.lastname: Shao
authors.affiliation: College of Resources and Environmental Sciences, Nanjing Agricultural University, No. 1 Weigang Road, Nanjing 210095, PR China.
authors.forename: Dorothy Kemuma
authors.initials: DK
authors.lastname: Mugambi
authors.affiliation: College of Food Science and Technology, Nanjing Agricultural University, No. 1 Weigang Road, Nanjing 210095, PR China. Electronic address: qiuhuihu@njau.edu.cn.
authors.forename: Qiu-hui
authors.initials: QH
authors.lastname: Hu
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology*; D002460:Cell Line; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D045424:Complex Mixtures / Q000737:chemistry; D048690:Fruiting Bodies, Fungal; D006801:Humans; D006861:Hydrogen Peroxide / Q000378:metabolism; D007155:Immunologic Factors / Q000494:pharmacology*; D008247:Lysosomes / Q000378:metabolism; D008264:Macrophages / Q000187:drug effects / Q000502:physiology; D051379:Mice; D009569:Nitric Oxide / Q000378:metabolism; D010455:Peptides / Q000494:pharmacology*; D010873:Pinocytosis / Q000187:drug effects; D020076:Pleurotus; D011208:Powders
chemical_list: D000970:Antineoplastic Agents; D045424:Complex Mixtures; D007155:Immunologic Factors; D010455:Peptides; D011208:Powders; D009569:Nitric Oxide; D006861:Hydrogen Peroxide
keywords: Cytotoxicity; Extraction; Immumodulation; Pleurotus eryngii (DC. ex Fr.) Quel powder