Is Necator americanus approaching a mutualistic symbiotic relationship with humans?
The hookworm Necator americanus establishes infections of impressive longevity in the immunologically hostile environment of its human host. In the process, it promotes pronounced T-helper 2 (Th2) cell activity, which in turn seemingly affords the host at least a degree of protection. Given the relatively asymptomatic nature of infection, we argue here that Necator americanus might be approaching a mutualistic symbiotic relationship with humans. In our view, infection is controlled by the immune system while being supported by a subtle immune-evasion strategy that is tolerated and possibly beneficial to the host in certain immunological circumstances, such as in counterbalancing potentially damaging Th1 responses.
Pritchard
D I
DI
Boots Science Institute, School of Pharmaceutical Sciences, University of Nottingham, University Park, NG7 2RD, Nottingham, UK. pazdp@gwmail.nottingham.ac.uk
Brown
A
A
D000595:Amino Acid Sequence; D000818:Animals; D015801:Helminth Proteins / Q000737:chemistry; D006790:Host-Parasite Interactions; D006801:Humans; D008969:Molecular Sequence Data; D017221:Necator americanus / Q000502:physiology*; D009332:Necatoriasis / Q000276:immunology / Q000469:parasitology*; D013559:Symbiosis
D015801:Helminth Proteins