Endogenous interleukin-10 produced by antigen-irrelevant cells promotes the development of experimental murine allergic conjunctivitis.
Interleukin (IL)-10 is known to act as an immunoregulatory cytokine in both T helper cell 1 (Th1)- and Th2-mediated immune responses. Here, we ask whether IL-10 regulates the development of experimental allergic conjunctivitis (EC), a Th2-mediated inflammatory disease. Wild-type (WT) and IL-10 knockout (IL-10 KO) mice were immunized with ragweed (RW) and then repeatedly challenged with RW in eye drops. Twenty-four hours after the final challenge, conjunctivas were harvested for histological analysis, while the blood and spleens were used to determine the RW-specific immunoglobulin levels in serum and proliferation or cytokine responses and splenocyte transfer, respectively. The IL-10 KO mice had significantly less severe EC (as determined by conjunctival eosinophil infiltration) than the WT mice and evinced greater RW-specific splenocyte proliferation and cytokine production. However, the RW-specific immunoglobulin levels of the two strains did not differ. When the splenocytes from RW-primed WT mice were transferred into IL-10 KO or WT mice, the IL-10 KO mice showed significantly less conjunctival eosinophil infiltration. In contrast, when the splenocytes from RW-primed IL-10 KO or WT mice were transferred into WT mice, both splenocyte populations generated equivalent severe EC. These data indicate that IL-10 does not serve as an immunoregulatory cytokine in the development of EC. Instead, it appears that IL-10 produced by antigen-irrelevant cells acts in the effector phase to promote the development of EC.
Fukushima
Atsuki
A
Department of Ophthalmology, Kochi Medical School, Oko-cho, Nankoku-city, Japan. fukusima@med.kochi-u.ac.jp
Sumi
Tamaki
T
Fukuda
Ken
K
Kumagai
Naoki
N
Nishida
Teruo
T
Ueno
Hisayuki
H
D019264:Adoptive Transfer; D031164:Ambrosia / Q000276:immunology*; D000818:Animals; D052179:Antigens, Plant / Q000276:immunology; D003228:Conjunctiva / Q000276:immunology* / Q000378:metabolism; D003233:Conjunctivitis, Allergic / Q000276:immunology* / Q000378:metabolism*; D004195:Disease Models, Animal; D016753:Interleukin-10 / Q000096:biosynthesis* / Q000172:deficiency / Q000235:genetics / Q000502:physiology*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D013154:Spleen / Q000166:cytology / Q000276:immunology / Q000378:metabolism / Q000637:transplantation; D018418:Th2 Cells / Q000276:immunology / Q000378:metabolism; D015854:Up-Regulation / Q000276:immunology
D052179:Antigens, Plant; D016753:Interleukin-10