Article Text

other Versions

Does Helicobacter pylori protect against asthma and allergy?
  1. Martin J Blaser (martin.blaser{at}
  1. NYU School of Medicine, United States
    1. Yu Chen (y.chen{at}
    1. NYU School of Medicine, United States
      1. Joan Reibman (joan.reibman{at}
      1. NYU School of Medicine, United States


        The microbes that persistently colonize their vertebrate hosts are not accidental (1). Although highly numerous and diverse, there is specificity by site and substantial conservation between individuals. The genus Helicobacter includes spiral, highly motile, urease-positive, gram-negative bacteria that colonize the stomach in many mammals. Each mammal has one or more dominant Helicobacter species and they are highly, if not exclusively, host species-specific (2). Such observations are consistent with the hypothesis that when ancestral mammals diverged from reptiles about 150 million years ago, they contained ancestral helicobacters, which then diverged as their hosts changed. According to this hypothesis, helicobacters represent ancestral biota (flora) in the mammalian stomach. The human-adapted strain is H. pylori (3), which has not been reproducibly observed in any animals other than humans and other primates (3).

        • Gastric physiology
        • Immunology
        • Inflammation
        • Microbiology
        • Stomach

        Statistics from

        Request permissions

        If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.