Is epidermal cell proliferation in psoriatic skin grafts on nude mice driven by T-cell derived cytokines?
Plasminogen activity and DNA synthesis by epidermal cells have been reported to be doubled in psoriatic skin grafts compared with grafts of normal skin 6 weeks after transplantation to nude mice. In our study human lymphocytes disappeared from such grafts within 48 h whilst some DR-positive human dendritic cells were retained in the grafts for up to 4 weeks. However, the grafts were infiltrated by Thy 1.2+ mouse lymphocytes within 6 days and this infiltration persisted at a moderate level throughout the observation period. It consisted of perivascular aggregates, scattered dermal and papillary T cells, and some mouse T cells were also found in the epidermal compartment. Grafts of psoriatic and non-psoriatic control skin were infiltrated to a similar extent, suggesting a low-grade rejection response against the human xenografts. These findings raise the possibility that psoriatic keratinocytes are responding abnormally to inflammatory cytokines released by mouse lymphocytes reacting against the skin grafts.
Baker
B S
BS
Department of Immunology, St Mary's Hospital and Medical School, London, U.K.
Brent
L
L
Valdimarsson
H
H
Powles
A V
AV
al-Imara
L
L
Walker
M
M
Fry
L
L
D000818:Animals; D002455:Cell Division / Q000502:physiology; D016207:Cytokines / Q000502:physiology*; D003713:Dendritic Cells / Q000473:pathology; D004195:Disease Models, Animal; D004817:Epidermis / Q000276:immunology / Q000473:pathology; D005455:Fluorescent Antibody Technique; D006084:Graft Rejection / Q000276:immunology; D006801:Humans; D051379:Mice; D008819:Mice, Nude; D011565:Psoriasis / Q000276:immunology / Q000473:pathology*; D016038:Skin Transplantation / Q000502:physiology*; D013601:T-Lymphocytes / Q000276:immunology / Q000473:pathology; D014183:Transplantation, Heterologous
D016207:Cytokines