Article

Chronic helminth infections modulate allergen-specific immune responses: Protection against development of allergic disorders?

Department of Parasitology, Leiden University Medical Center, Leiden, the Netherlands.
Annals of Medicine (Impact Factor: 4.73). 02/2007; 39(6):428-39. DOI: 10.1080/07853890701436765
Source: PubMed

ABSTRACT Inflammatory diseases are on the rise in westernized countries, but also in urbanized areas of developing countries. A number of studies have now demonstrated a negative association between helminth infections and inflammatory diseases, such as allergy, suggesting a potential role for helminth-induced immune responses. However, this is not the case for all studies. In this review both supporting and opposing literature on the role of helminth infections, particularly in allergy, are discussed. Furthermore, the concept is put forward that chronic helminth infections, but not acute infections, may be associated with the expression of regulatory networks necessary for downmodulating allergic immune responses to harmless antigens. Lastly, different components of helminth-induced regulatory networks are detailed, such as the role of regulatory T and B cells, modulation of dendritic cells, the presence of suppressory alternatively activated macrophages, and their individual contributions to protection against allergic diseases. Advantage should be taken from this knowledge to identify and select individual helminth-derived molecules that may harbor therapeutic potential against inflammatory diseases.

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    • "For instance, BALB/c mice exposed to Schistosoma japonicum eggs produced more IL-10 but little IL-4 (Yang et al. 2007). While mice chronically infected with Schistosoma mansoni have downregulated levels of IL-4, IL-10, IL-13 and IFN-γ (Smits and Yazdanbakhsh 2007). Moreover, in another study, infection with Schistosoma haematobium induced significant production of IL-5 and IL-10 (van den Biggelaar et al. 2000). "
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