Effects of purified protein derivative (PPD)-activated syngeneic epidermal cells on a PPD-specific rat T-helper cell line.
An important question in local immune regulation in the skin is how keratinocytes at inflammatory sites can modify a local T-cell response to antigens introduced via the skin. In the present study we investigated the effects of rat epidermal cells obtained from the site of a tuberculin reaction, on the proliferative response of a syngeneic purified protein derivative (PPD)-specific CD4+ T-cell line. Epidermal cell suspensions from the tuberculin-reactive ears contained 23-37% cells expressing class II transplantation antigens as judged by immunocytochemistry compared with 2-3% in normal epidermis. When comparing the capacity of these two different epidermal cell populations to induce a PPD-specific T-cell response in vitro, it was found that the PPD-reactive epidermal cells induced a lower T-cell response than did normal epidermal cells. This discrepancy cannot be explained by an infiltration of inflammatory cells into the epidermis of tuberculin-reactive ears. Our data indicate that epidermal cells modified during a delayed-type hypersensitivity reaction in vivo may suppress an antigen-specific T-cell proliferation.
Scheynius
A
A
Department of Clinical Immunology, Karolinska Institute, Stockholm, Sweden.
Larsson
P
P
Skoglund
C
C
Holmdahl
R
R
Klareskog
L
L
D000818:Animals; D002460:Cell Line; D004817:Epidermis / Q000276:immunology*; D005260:Female; D006684:HLA-DR Antigens / Q000032:analysis; D007124:Immunoenzyme Techniques; D007371:Interferon-gamma / Q000494:pharmacology; D008213:Lymphocyte Activation; D008297:Male; D051381:Rats; D011917:Rats, Inbred Lew; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*; D014373:Tuberculin / Q000276:immunology*
D006684:HLA-DR Antigens; D014373:Tuberculin; D007371:Interferon-gamma