Ascaris lumbricoides-induced interleukin-10 is not associated with atopy in schoolchildren in a rural area of the tropics.
BACKGROUND
In areas where intestinal helminth infections are endemic, infections by these parasites may protect against skin test-measured reactivity to allergens, and it has been suggested that interleukin (IL)-10 may mediate this effect. This study investigated whether IL-10 and populations of IL-10+ T cells may modulate atopy in children living in an area where intestinal helminth infections are endemic.


METHODS
Ecuadorian schoolchildren from rural communities were assessed for skin test-measured reactivity to Periplaneta americana allergen and Dermatophagoides pteronyssinus allergen. Blood samples were collected from 39 skin test-positive and 41 skin test-negative children, and peripheral-blood leukocytes were cultured in the presence of Ascaris lumbricoides antigen, to measure IL-10 protein and the frequency of T cell populations expressing intracellular IL-10. We also investigated whether these immunological factors affected the association between allergen-specific IgE and skin test-measured reactivity to aeroallergens.


RESULTS
There was no evidence of association between the level of A. lumbricoides-induced IL-10 protein or IL-10+ T cells and skin test-measured reactivity to allergens. The association between allergen-specific IgE and skin test-measured reactivity was not affected by the level of IL-10 protein or the frequency of IL-10+ T cells.


CONCLUSIONS
The results of this study do not support the notion that IL-10 plays a role in modulating atopy in children living in a tropical area where intestinal helminth infections are endemic.
Cooper
Philip J
PJ
Laboratorio de Investigaciones, Hospital Pedro Vicente Maldonado, Pichincha Province, Quito, Ecuador. pcooper@ecnet.ec
Mitre
Edward
E
Moncayo
Ana Lucia
AL
Chico
Martha E
ME
Vaca
Maritza G
MG
Nutman
Thomas B
TB
D000818:Animals; D000909:Antibodies, Helminth / Q000097:blood; D001196:Ascariasis / Q000276:immunology*; D017164:Ascaris lumbricoides / Q000276:immunology*; D002648:Child; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D006967:Hypersensitivity / Q000517:prevention & control*; D016753:Interleukin-10 / Q000276:immunology / Q000378:metabolism*; D007963:Leukocytes, Mononuclear / Q000276:immunology / Q000378:metabolism; D008297:Male; D012424:Rural Population; D012882:Skin Tests
D000909:Antibodies, Helminth; D016753:Interleukin-10