Helpful Helminths

See allHide authors and affiliations

Science  02 Dec 2005:
Vol. 310, Issue 5753, pp. 1393
DOI: 10.1126/science.310.5753.1393a

Pathogens have evolved countless devious means of thriving within their hosts. These range from antigenic escape from the attention of B and T cells to usurping the early detection network of the innate immune system.

Wilson et al. provide evidence to suggest that the nematode gut parasite Heligmosomoides polygyrus protects itself by suppressing allergic T cell responses in the host. Nematode infection was found to decrease the pulmonary allergic inflammation normally evoked in mice by an allergen from the house dust mite. Tying several lines of evidence together, the effects were narrowed to a population of regulatory CD4+ T cells from gut-associated lymph nodes of infected mice. Smith et al. found that another helminth, the trematode parasite Schistosoma mansoni, produces a chemokine-binding protein (CKBP) to protect itself from the ill effects of host inflammation. CKBP was detected specifically in the egg stage of the parasite and bound CXCL8 (IL-8) and CCL3 (MIP1a). Predominantly through effects on neutrophil activity, CKBP inhibited different forms of experimental inflammation in mice. Both studies reveal a new layer of diversity by which helminths modify their host environment. — SJS

J. Exp. Med. 202, 1199; 1319 (2005).

Navigate This Article