Predominance of T lymphocytes in the dermal infiltrate of atopic dermatitis

Abstract

Tissue sections from diseased skin of sixteen patients with atopic dermatitis were investigated with haematoxylin-eosin and toluidine-blue staining, with direct immunofluorescence staining using FITC-conjugated antisera against IgG F(ab')2 and IgM, and with the indirect immunofluorescence method utilizing specific rabbit anti-human T lymphocyte antiserum with FITC-conjugated goat anti-rabbit Ig antiserum as the second layer. Furthermore, cryostat sections were investigated in a closed chamber immune adherence method using aminoethylisothiouronium bromide (AET) treated sheep red blood cells to detect E receptors on T lymphocytes, and with various types of coated sheep red blood cells to detect cells with IgG Fc receptors and complement factor C3b receptors. All sections presented dermal perivascular infiltrates of mononuclear cells as judged by haematoxylin-eosin staining. Staining with toluidine-blue demonstrated varying numbers of mast-cells, but in no case pathological increased number. The majority of the infiltrating cells presented rim-like membrane fluorescence with the anti-T antiserum, and the AET treated sheep red blood cells (SRBC) adhered to the infiltrates, thus indicating a predominance of T lymphocytes in the skin infiltrates of atopic dermatitis.

Pimecrolimus leads to an apoptosis-induced depletion of T cells but not Langerhans cells in patients with atopic dermatitis

“…10 Whereas it has been shown in vitro that tacrolimus and pimecrolimus mainly mediate their immunosuppressive mode of action on T cells by blocking the synthesis of cytokines, 33,34 the mechanisms by which T-cell depletion is achieved in vivo have remained unclear so far. With regard to tacrolimus, it has been shown most recently that its ointment abolishes classical immunologic abnormalities associated with AD, such as the mixed cellular infiltrate of the dermis and the high expression of cytokines by infiltrating cells.…”

“…[10][11][12][13] On topical treatment with calcineurin inhibitors, this inflammatory cell infiltrate is markedly decreased, as evidenced by a tacrolimus-induced reduction of IDECs, eosinophils, and T cells. [14][15][16] However, the mechanisms leading to the disappearance of inflammatory cells have remained unclear so far.…”

Prominent Involvement of Activated Th1-Subset of T-Cells and Increased Expression of Receptor for IFN-Gamma on Keratinocytes in Atopic Dermatitis Acute Skin Lesions

“…Analysis of AD skin lesions reveals a mononuclear infiltrate consisting of lymphocytes, predominantly by CD4+ T-cells, monocytes, and an increased intraepidermal LC count, mainly in the perivascular parts of the dermis, and to a lesser extent in the epidermis [14,15,16,17]. Perivascular infiltrate in the dermis of AD skin lesions consisted of activated helper CD4+ T lymphocytes expressing HLA-DR+ (an increased number of activated memory T-cells), a large number of APCs such as CD1a+ cells (dendritic cells, DCs) (10–15%), macrophages (10%), and interdigitating reticulum cells (20%) [18].…”

Anti-Interleukin-5 Antibody Therapy in Eosinophilic Diseases

“…In the dermis, there is a perivascular infi ltrate composed predominantly of T cells and a variable number of eosinophils [42,43] . Recent research provided evidence that IL-5 and eosinophils are important pathogenic factors in AD [44,45] .…”