title: [Comparison between the LLC-MK2 and MDCK cell lines in the isolation of parainfluenza virus from nasopharyngeal aspirates].
abstract: BACKGROUND
  We report a prospective comparative study of the efficacy of three commercial cell lines in the isolation of the parainfluenza (PI) virus from nasopharyngeal samples.
  
  
  METHODS
  In a 16 months period we studied all nasopharyngeal samples from patients with the suspension of a viral respiratory infection. The compared cell lines were LLC-MK2 and MDCK. All samples were processed by the shell-vial assay, incubated 3 days at 36 degrees C. The monolayers were stained by an indirect immunofluorescence assay with a monoclonal antibody against the nucleoprotein of the PI virus.
  
  
  RESULTS
  In the study period 746 samples were analyzed, 46 PI virus were isolated, all belonged to the serotype 3. The LLC-MK2 cell line isolated 44 viruses (95.6%) and the MDCK cell line 41 (89.1%), no statistically significant differences were detected (p = 0.14) (qualitative sensitivity). In 84.8% of positive samples, the PI virus was isolated simultaneously in the two cell lines. Neither cell line isolated all PI virus. No statistical differences were detected in the quantitative sensitivity, although the LLC-MK2 cell line detected a slightly more samples with a low viral load (70.4 vs 68.2%).
  
  
  CONCLUSIONS
  In view of the results obtained in this study, we believe that anyone of the two cell lines would be used in the isolation of the PI virus from respiratory samples.
authors.affiliation: Unidad de Virología, Hospital Universitario Son Dureta, Palma de Mallorca.
authors.forename: J
authors.initials: J
authors.lastname: Reina
authors.forename: J
authors.initials: J
authors.lastname: Saurina
authors.forename: M
authors.initials: M
authors.lastname: Munar
authors.forename: I
authors.initials: I
authors.lastname: Blanco
mesh_terms: D002460:Cell Line; D006801:Humans; D010224:Parainfluenza Virus 3, Human / Q000302:isolation & purification*; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D014773:Virology / Q000379:methods