title: Pathogenic assays of acanthamoeba belonging to the t4 genotype.
abstract: BACKGROUND
  Acanthamoeba genus is introduced as opportunistic and cosmopolitan parasite. Monkey and wistar rat are appropriate models for experimental study on Acanthamoeba infection. In this study Acanthamoeba spp. were isolated from hot spring (HS), windows dust (WD) and a corneal sample of keratitis patient (KP) and their pathogenicity surveyed by in vitro and in vivo tests.
  
  
  METHODS
  Isolates of Acanthamoeba were cultivated axenically for 12 months in PYG medium. Overall, 30 wistar rats, in 6 equal groups were used for developing experimental Acanthamoeba keratitis (AK) and Granulomatous Amoebic Encephalitis (GAE). The Keratitis and Granulomatous Encephalitis experiments were performed by intrastromal and intranasal inoculation of Acanthamoeba cysts, respectively. Pathogenicity of the three isolates was also evaluated by in vitro test using osmotolerance and temperature tolerance assays. Identification of genotypes were performed by PCR technique and sequencing.
  
  
  RESULTS
  None of the isolates could perform AK and GAE in wistar rats, although all isolates were described as T4 genotype. Isolates obtained from KP and WD could grow only in 30 °C, but not in 37 °C and 40 °C. On the other hand, HS isolate grew in 30 °C and 37 °C but not in 40 °C. Moreover, all of isolate grew in 0.5 M mannitol but not in 1 M and 1.5 M.
  
  
  CONCLUSIONS
  T4 isolates with a long-term axenic culture and different factors related to host and parasite may play role in pathogenicity of these free-living amoebae.
authors.affiliation: Dept. of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Hamed
authors.initials: H
authors.lastname: Mirjalali
authors.affiliation: Dept. of Medical Parasitology and Mycology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Maryam
authors.initials: M
authors.lastname: Niyyati
authors.affiliation: Dept. of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Hoda
authors.initials: H
authors.lastname: Abedkhojasteh
authors.affiliation: Dept. of Parasitology, School of Medicine, Kerman University of Medical Sciences, Kerman, Iran.
authors.forename: Zahra
authors.initials: Z
authors.lastname: Babaei
authors.affiliation: Dept. of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Meysam
authors.initials: M
authors.lastname: Sharifdini
authors.affiliation: Dept. of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran ; Center for Research of Endemic Parasites of Iran (CREPI), Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Mostafa
authors.initials: M
authors.lastname: Rezaeian
keywords: Acanthamoeba T4; Experimental Model; Osmotolerance; Pathogenicity; Rat