Interleukin-10 limits local and body cavity inflammation during infection with muscle-stage Trichinella spiralis.
The aim of this study was to characterize cellular responses to muscle-stage Trichinella spiralis. From its intracellular habitat in muscle, T. spiralis secretes potent glycoprotein antigens that elicit a strong systemic host immune response. Despite the magnitude and prolonged nature of this response, nurse cells are rarely destroyed by infiltrating cells. We tested the hypothesis that the anti-inflammatory cytokine interleukin-10 (IL-10) moderates cellular responses to muscle-stage parasites. Trichinella larvae colonize the diaphragm in large numbers, prompting us to evaluate regional responses in body cavities in addition to local responses in muscle. Mice deficient in IL-10 demonstrated an exaggerated inflammatory response around nurse cells and in the pleural cavity. The effect of IL-10 was most evident 20 days following muscle infection. The increased intensity of the response in IL-10-deficient mice did not affect parasite establishment or survival. Between 20 and 50 days postinfection, the inflammatory response was diminished in both wild-type and IL-10-deficient mice. Muscle infection also elicited an antibody response, characterized initially by mixed isotypes directed at somatic larval antigens and changing to an immunoglobulin G1-dominated response directed at tyvelose-bearing excreted or secreted antigens. We conclude that IL-10 limits local and regional inflammation during the early stages of muscle infection but that chronic inflammation is controlled by an IL-10-independent mechanism that is coincident with a Th2 response.
Beiting
Daniel P
DP
James A. Baker Institute for Animal Health, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA. db225@cornell.edu
Bliss
Susan K
SK
Schlafer
Donald H
DH
Roberts
Victoria L
VL
Appleton
Judith A
JA
D000208:Acute Disease; D000818:Animals; D002908:Chronic Disease; D007249:Inflammation / Q000276:immunology*; D016753:Interleukin-10 / Q000276:immunology* / Q000378:metabolism; D007814:Larva / Q000472:pathogenicity; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D009132:Muscles / Q000276:immunology / Q000469:parasitology* / Q000503:physiopathology; D010529:Peritoneal Cavity / Q000502:physiology*; D035422:Pleural Cavity / Q000276:immunology*; D051381:Rats; D017160:Trichinella spiralis / Q000254:growth & development / Q000276:immunology / Q000472:pathogenicity*; D014235:Trichinellosis / Q000276:immunology* / Q000469:parasitology
D016753:Interleukin-10