title: ALS1 and ALS3 gene expression and biofilm formation in Candida albicans isolated from vulvovaginal candidiasis.
abstract: BACKGROUND
  A cluster of genes are involved in the pathogenesis and adhesion of Candida albicans to mucosa and epithelial cells in the vagina, the important of which is agglutinin-like sequence (ALS) genes. As well as vaginitis is a significant health problem among women, the antifungal resistance of Candida species is continually increasing. This cross-sectional study investigates the expression of ALS1 and ALS3 genes and biofilm formation in C. albicans isolate isolated from vaginitis.
  
  
  METHODS
  Fifty-three recognized isolates of C. albicans were collected from women with recurrent vulvovaginal candidiasis in Iran, cultured on sabouraud dextrose agar, and then examined for gene expression. Total messenger RNA (mRNA) extracted from C. albicans isolates and complementary DNA synthesized using reverse transcriptase enzyme. Reverse transcription-polymerase chain reaction (RT-PCR) using specific primer was used to evaluate the expression of ALS1 and ALS3 through housekeeping (ACT1) genes. 3-(4,5-dimethyl-2-thiazyl)-2,5-diphenyl-2H-tetrazolium bromide assay was performed to assess adherence capacity and biofilm formation in the isolated.
  
  
  RESULTS
  Forty isolates (75.8%) expressed ALS1 and 41 isolates (77.7%) expressed ALS3 gene. Moreover, 39 isolates (74%) were positive for both ALS1 and ALS3 mRNA by the RT-PCR. Adherence capability in isolates with ALS1 or ALS3 genes expression was greater than the control group (with any gene expression), besides, it was significantly for the most in the isolates that expressed both ALS1 and ALS3 genes simultaneously.
  
  
  CONCLUSIONS
  The results attained indicated that there is an association between the expression of ALS1 and ALS3 genes and fluconazole resistance in C. albicans. A considerable percent of the isolates expressing the ALS1 and ALS3 genes may have contributed to their adherence to vagina and biofilm formation.
authors.affiliation: Department of Mycology, Faculty of Medical Science, Tarbiat Modares University, Tehran, Iran.
authors.forename: Shahla
authors.initials: S
authors.lastname: Roudbarmohammadi
authors.affiliation: Department of Parasitology and Mycology, School of Medicine, Iran University of Medical Science, Tehran, Iran.
authors.forename: Maryam
authors.initials: M
authors.lastname: Roudbary
authors.affiliation: Department of Bacteriology, Faculty of Medical Science, Tarbiat Modares University, Tehran, Iran.
authors.forename: Bita
authors.initials: B
authors.lastname: Bakhshi
authors.affiliation: Department of Pathobiology, Faculty of Veterinary Medicine, University of Tabriz, Tabriz, Iran.
authors.forename: Farzad
authors.initials: F
authors.lastname: Katiraee
authors.affiliation: Department of Medical Parasitology and Mycology, School of Medicine, Isfahan University of Medical Science, Isfahan, Iran.
authors.forename: Rasoul
authors.initials: R
authors.lastname: Mohammadi
authors.affiliation: Department of Parasitology and Mycology, School of Medicine, Iran University of Medical Science, Tehran, Iran.
authors.forename: Mehraban
authors.initials: M
authors.lastname: Falahati
keywords: Agglutinin-like sequence proteins; Candida albicans; biofilm formation; vulvovaginal candidiasis