title: [The anti-respiratory syncytial virus effect of an active compound (AP3) from a Chinese medicinal herb-Herba patriniae in vitro].
abstract: OBJECTIVE
  To study the effect on anti-respiratory syncytial virus of an active compound (AP3) from a Chinese medicinal herb-Herba patriniae in vitro.
  
  
  METHODS
  Active component of herba patriniae (AP3) was extracted and its anti-respiratory syncytial virus (RSV) effect was tested. A water soluble substance (AP3) was isolated from a Chinese herb Herba patriniae, by hot water extraction, ethol precipitation and gel permeation column chromatography. The cytotoxicity of AP3 was tested by adding it to HeLa cells directly. Its effect against RSV was estimated by CPEI assay while ribavirin was used as positive control.
  
  
  RESULTS
  Chemical test showed that the nature of substance AP3 was polysaccharide. The median cytotoxic concentration (TC(50)) of AP3 was 11.45 mg/ml by morphological observation and the median effective concentration (50% effective concentration, EC(50)) of it against replication of the long strain of RSV in HeLa cells was 0.0986 mg/ml. The Therapeutic index (TI = TC(50)/EC(50)) of AP3 was 116.12, much higher than the TI of herba patriniae (AP1) (TI = 59.26) and ribavirin (TI = 53.45). Moreover, AP3 gave a dose-dependent response in inhibiting RSV. In the assay, the effect of AP3 against RSV growth was also tested. In addition, the effect of AP3 on virus growth, AP3 inhibited replication of RSV in HeLa cells, when added at 0 h, 2 h, 4 h after virus infection, were also tested.
  
  
  CONCLUSIONS
  This study suggested that the AP3 exerted an obvious inhibitory effect to RSV in HeLa cell culture. This study furnished a reliable evidence for development of a new antiviral drug.
authors.affiliation: College of Public Health, Harbin Medical University, Harbin 150001, China.
authors.forename: Shan-shan
authors.initials: SS
authors.lastname: Li
authors.forename: Hong-yuan
authors.initials: HY
authors.lastname: Li
authors.forename: Ying-ai
authors.initials: YA
authors.lastname: Piao
authors.forename: Dian-li
authors.initials: DL
authors.lastname: Liu
authors.forename: Wen-jing
authors.initials: WJ
authors.lastname: Tian
authors.forename: Yan-mei
authors.initials: YM
authors.lastname: Dong
mesh_terms: D000998:Antiviral Agents / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004365:Drugs, Chinese Herbal / Q000494:pharmacology*; D006367:HeLa Cells; D006801:Humans; D012136:Respiratory Syncytial Viruses / Q000187:drug effects*; D013997:Time Factors
chemical_list: D000998:Antiviral Agents; D004365:Drugs, Chinese Herbal