Increased numbers of CD4+ and CD8+ T cells in lesional skin of cats with allergic dermatitis.
The aim of this study was to characterize T cells in the skin of cats with an allergic dermatitis histologically compatible with atopic dermatitis, since T cells play an important role in the pathogenesis of atopic dermatitis in humans. We observed a significantly greater number of T cells in lesional skin of domestic short-haired cats with allergic dermatitis (n = 10; median age 5.8 years) than in the skin of healthy control animals (n = 10; median age 5.0 years). In the skin of the healthy control animals, one or two CD4+ cells and no CD8+ cells were found. A predominant increase of CD4+ T cells and a CD4+/CD8+ ratio (mean +/- SD: 3.9 +/- 2.0) was found in the lesional skin of 10 cats with allergic dermatitis. The CD4+/CD8+ cell ratio in the skin of healthy control animals could not be determined because of the absence of CD8+ cells. The CD4+/CD8+ cell ratio in the peripheral blood of 10 cats with allergic dermatitis (mean +/- SD: 1.9 +/- 0.4) did not differ significantly from that in 10 healthy control animals (2.2 +/- 0.4). The CD4+/CD8+ cell ratio and predominance of CD4+ T cells in the lesional skin of cats with allergic dermatitis is comparable to that found in atopic dermatitis in humans. In addition, the observed increase of CD4+ T cells in the nonlesional skin of cats with allergic dermatitis compared to the skin of healthy cats is similar to what is seen in humans. Cytokines produced by T cells and antigen-specific T cells are important mediators in the inflammatory cascade resulting in atopic dermatitis in humans. This study is a first step to investigate their role in feline allergic dermatitis.
Roosje
P J
PJ
Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht, The Netherlands.
van Kooten
P J
PJ
Thepen
T
T
Bihari
I C
IC
Rutten
V P
VP
Koeman
J P
JP
Willemse
T
T
D000818:Animals; D018791:CD4 Lymphocyte Count / Q000662:veterinary; D016516:CD4-CD8 Ratio / Q000662:veterinary; D015496:CD4-Positive T-Lymphocytes / Q000473:pathology*; D018414:CD8-Positive T-Lymphocytes / Q000473:pathology*; D002371:Cat Diseases / Q000276:immunology / Q000473:pathology*; D002415:Cats; D003876:Dermatitis, Atopic / Q000276:immunology / Q000473:pathology / Q000662:veterinary*; D005260:Female; D005434:Flow Cytometry / Q000662:veterinary; D006965:Hyperplasia / Q000473:pathology; D008297:Male; D012867:Skin / Q000276:immunology / Q000473:pathology*; D012882:Skin Tests / Q000662:veterinary; D016176:T-Lymphocyte Subsets