title: The Role ofVibrio choleraeHaemagglutinin Protease (HAP) in Extra-Intestinal Infection.
abstract: BACKGROUND
  Based on the diversity of surface O antigenVibrio choleraecan be classified into 206 serogroups.Vibrio choleraeis the causative agent of cholera and extra intestinal infections like, septicemia, wound infection and haemorrhagic reactions. Pathogenic factors ofV. choleraeextra-intestinal infection are yet to be explored.
  
  
  OBJECTIVE
  To identify the pathogenic factor associated withV. choleraeextra-intestinal infection.
  
  
  METHODS
  This study was carried out between April, 2007 to October 2007 in National Institute of Cholera and Enteric Diseases (NICED). Haemagglutinin Protease (HAP), a major secreted proteolytic enzyme, was purified from the culture supernatant ofVibrio choleraeO1 strain C6709 after removal of outer membrane vesicles using a single step ion-exchange chromatography. Function of HAP was characterized by animal model, like, subcutaneous mouse assay, basement membrane component's degradation assays and tissue culture assays.
  
  
  RESULTS
  When suckling mouse was subcutaneously injected with culture supernatant of C6709 strain or purified HAP in both cases, distinct in vivo haemorrhagic response along with histopathological changes like necrosis of the capillaries and muscle layer, acute myofibre degeneration as well as moderate number of erythrocyte scattered through the skin, capillary necrosis, acute myofiber degeneration and necrosis of muscle layer were found. When Tryptic Soy Broth (TSB) media was used, the haemorrhagic effects in suckling mouse were not detectable. The major protein components, laminin and collagen, of basement membrane comprising of vascular endothelial cells, were degraded by HAP. Purified HAP showed cell rounding effects on Int 407 cells.
  
  
  CONCLUSIONS
  Result indicates that HAP may be a causative agent ofVibrio choleraemediated extra-intestinal infection. This study confirms thatVibrio choleraas a sole pathogen can cause the extra-intestinal infection. This information is important for public health notification. Besides this, result indicates appropriate testing forVibrio choleraeand intervention are important for the patient management.
authors: Assistant Professor, Department of Physiology, All India Institute of Medical Sciences , Bhubaneswar, Odisha, India .
authors: Amit
authors: A
authors: Ghosh
authors: Scientist D, National Institute of Cholera and Enteric Diseaes , Kolkata, India .
authors: Hemanta
authors: H
authors: Koley
authors: Scientist E, National Institute of Cholera and Enteric Diseaes , Kolkata, India .
authors: Amit
authors: A
authors: Pal
keywords: Ion exchange chromatography; Metalloprotease; Septicemia