title: Anti-HIV-1 activity determined by β-galactosidase activity in the multinuclear activation of an indicator assay is comparable with that by a conventional focus counting method.
abstract: BACKGROUND
  Direct comparison of enzymatic and original blue cell-counting detections with the multinuclear activation of an indicator (MAGI) cells, so far, remains to be performed in parallel. Although inhibitors for reverse transcription solely inhibit the reverse transcription step, those for HIV-1 entry block syncytium formation of HIV-1-infected MAGI cells in addition to the entry (dual inhibition). It raises a concern that reduction of enzymatic activity is artificially influenced by syncytium-blocking activity of inhibitors for entry.
  
  
  METHODS
  The MAGI cells with a syncytium inducible strain, HIV-1IIIB, were used for anti-HIV activity determination both with conventional counting with X-Gal staining and measurement of chlorophenol red β-d-galactopyranoside conversion with a plate reader.
  
  
  RESULTS
  Infectivity of HIV-1 in the MAGI cells was highly correlated with both methods. In microscopic observation, small blue cells with single or a couple of nuclei were dominantly observed in the presence of inhibitors for entry, but not in the presence of those for reverse transcription. Actual anti-HIV-1 activities were comparable or moderately sensitive in the chlorophenol red β-d-galactopyranoside method.
  
  
  CONCLUSIONS
  Antiviral activities of inhibitors for entry obtained from both enzymatic and counting methods appear to be comparable, even in infection of a highly syncytia inducible HIV-1IIIB strain.
authors.affiliation: Division of Miyagi Community Health Promotion, Tohoku University Graduate School of Medicine and Tohoku Medical Megabank Organization, Sendai, Japan Division of Infection Control and Laboratory Diagnostics, Department of Internal Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan.
authors.forename: Fusako
authors.initials: F
authors.lastname: Miyamoto
authors.affiliation: Division of Miyagi Community Health Promotion, Tohoku University Graduate School of Medicine and Tohoku Medical Megabank Organization, Sendai, Japan Division of Infection Control and Laboratory Diagnostics, Department of Internal Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan.
authors.forename: Kumi
authors.initials: K
authors.lastname: Kawaji
authors.affiliation: Graduate School of Pharmaceutical Science, Kyoto University, Kyoto, Japan.
authors.forename: Shinya
authors.initials: S
authors.lastname: Oishi
authors.affiliation: Graduate School of Pharmaceutical Science, Kyoto University, Kyoto, Japan.
authors.forename: Nobutaka
authors.initials: N
authors.lastname: Fujii
authors.affiliation: Division of Infection Control and Laboratory Diagnostics, Department of Internal Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan.
authors.forename: Mitsuo
authors.initials: M
authors.lastname: Kaku
authors.affiliation: Division of Miyagi Community Health Promotion, Tohoku University Graduate School of Medicine and Tohoku Medical Megabank Organization, Sendai, Japan Division of Infection Control and Laboratory Diagnostics, Department of Internal Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan kodama515@med.tohoku.ac.jp.
authors.forename: Eiichi N
authors.initials: EN
authors.lastname: Kodama
mesh_terms: D000480:Alkynes; D019380:Anti-HIV Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D048588:Benzoxazines / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D003521:Cyclopropanes; D004305:Dose-Response Relationship, Drug; D017930:Genes, Reporter / Q000235:genetics*; D015497:HIV-1 / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D008826:Microbial Sensitivity Tests; D013329:Structure-Activity Relationship; D015215:Zidovudine / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D001616:beta-Galactosidase / Q000032:analysis / Q000235:genetics / Q000378:metabolism*
chemical_list: D000480:Alkynes; D019380:Anti-HIV Agents; D048588:Benzoxazines; D003521:Cyclopropanes; D015215:Zidovudine; D001616:beta-Galactosidase; C098320:efavirenz
keywords: Enzyme; entry inhibitor; reverse-transcriptase inhibitor; screening; sensitivity