Interleukin 4-producing CD4+ T cells in the skin of cats with allergic dermatitis.
Lesional skin of cats with allergic dermatitis has a cellular infiltrate and a CD4/CD8 ratio comparable to that in humans with atopic dermatitis. CD4+ helper T cells and in particular cells belonging to the Th2 subset play an important role in disease pathogenesis in humans. We investigated the cytokine pattern of CD4+ T cells in situ, with special emphasis on the putative presence of cells producing interleukin 4 (IL4), in cats with allergic dermatitis. Immunohistochemical procedures were used to determine that CD4+ T cells in lesional and nonlesional skin of cats with allergic dermatitis can produce IL4, as occurs in humans. Lesional and nonlesional skin of cats with allergic dermatitis had significantly more IL4+ T cells (P = 0.001) than did skin of healthy control cats. Double staining indicated that all IL4+ cells were positive for pan-T or CD4 markers. Double labeling for mast cell chymase and IL4 stained primarily different cells. Western blotting demonstrated cross-reactivity between the antibody against human IL4 and a feline recombinant IL4. These results indicate that IL4 is primarily produced by CD4+ T cells and is also present in clinically uninvolved skin, indicating a role in the pathogenesis of allergic dermatitis in cats.
Roosje
P J
PJ
Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht University, The Netherlands.
Dean
G A
GA
Willemse
T
T
Rutten
V P M G
VP
Thepen
T
T
D000818:Animals; D015153:Blotting, Western / Q000662:veterinary; D018791:CD4 Lymphocyte Count / Q000662:veterinary; D016516:CD4-CD8 Ratio / Q000662:veterinary; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D002371:Cat Diseases / Q000276:immunology* / Q000473:pathology; D002415:Cats; D017449:Dermatitis, Allergic Contact / Q000276:immunology / Q000473:pathology / Q000662:veterinary*; D003876:Dermatitis, Atopic / Q000276:immunology / Q000473:pathology / Q000662:veterinary*; D005260:Female; D007150:Immunohistochemistry / Q000662:veterinary; D015847:Interleukin-4 / Q000096:biosynthesis*; D008297:Male; D012867:Skin / Q000276:immunology / Q000473:pathology*; D012882:Skin Tests / Q000662:veterinary; D016176:T-Lymphocyte Subsets
D015847:Interleukin-4