title: [Antibacterial activity and cytotoxicity of polypeptide dhvar4].
abstract: OBJECTIVE
  To investigate the antibacterial activity and the cytotoxicity of polypeptide dhvar4.
  
  
  METHODS
  Solid-phase synthesized dhvar4 was manufactured by MeiLian Biotech Co. Ltd.; we evaluated its antibacterial effect, using the growth curve of bacteria after the bacteria being treated with different concentration of dhvar4. The cytotoxicity of dhvar4 on L-02, ECV-304, 293, 3T3 cells was investigated by MTT assay, and human erythrocytes were subimitted to hemolytic assay.
  
  
  RESULTS
  dhvar4 inhibited the growth of Enterococcus faecium 36418 and Staphylococcus aureus BAA42 only at the concentration of 4 microg/ml. The viability of mammalian cells remained 68%-92% even when the concentration of dhvar4 reached 150 microg/ml. The LD50 (median lethal dose) was determined to be higher than 150 microg/ml. And very low hemolytic activity of dhvar4 was detected even at the highest protein concentration tested (180 microg/ml).
  
  
  CONCLUSIONS
  dhvar4 possesses antibacterial activity and has little cytotoxicity to mammalian cells. These results suggest that dhvar4 has great potential in the development of
authors.affiliation: Lab of Transplant Engineering and Immunology, West China Hospital, Sichuan University, Chengdu 610041, China.
authors.forename: Xia
authors.initials: X
authors.lastname: Gao
authors.forename: Xiao-feng
authors.initials: XF
authors.lastname: Lu
authors.forename: Sheng-fu
authors.initials: SF
authors.lastname: Li
authors.forename: Kun
authors.initials: K
authors.lastname: Gao
authors.forename: Jing-qiu
authors.initials: JQ
authors.lastname: Cheng
mesh_terms: D000935:Antifungal Agents / Q000138:chemical synthesis / Q000276:immunology / Q000494:pharmacology*; D003602:Cytotoxicity, Immunologic; D054808:Histatins; D006801:Humans; D010455:Peptides / Q000494:pharmacology; D012471:Salivary Proteins and Peptides / Q000138:chemical synthesis / Q000276:immunology / Q000494:pharmacology*
chemical_list: D000935:Antifungal Agents; C068075:HTN3 protein, human; D054808:Histatins; D010455:Peptides; D012471:Salivary Proteins and Peptides; C494062:dhvar4 peptide