Identification of TIA-1+ and granzyme B+ cytotoxic T cells in lichen sclerosus et atrophicus.
BACKGROUND
The onset and persistence of cutaneous lichen sclerosus et atrophicus (LSA) are linked to the presence of an inflammatory infiltrate of CD3+ T cells that includes CD4+ and CD8+ cells. The functional relevance of the presence of these cells is unknown.


OBJECTIVE
The study intended to quantify resting and activated cytotoxic T cells in LSA lesions.


METHODS
Twenty patients with active LSA were studied. Skin-infiltrating T cells were immunohistologically characterized with antibodies against CD3, CD8, T-cell-restricted intracellular antigen (TIA-1) and granzyme B (GrB). TIA-1 labels cytotoxic granules of resting and activated T cells, whereas GrB designates activated cytotoxic T lymphocytes (CTL).


RESULTS
In all cases, numerous T cells were consistently found expressing cytotoxic granules. The results indicated a high number of infiltrating CD8+ TIA+ T cells. Furthermore, a notable number of GrB+ activated CTL associated with hydropic degeneration of the basal cell layer were found within the dermal infiltrate and at the dermoepidermal interface.


CONCLUSIONS
This study shows that a high proportion of skin-infiltrating T cells in LSA has a potential cytotoxic function. The results indicate that hydropic degeneration of basal keratinocytes may at least partially be mediated by CTL-dependent mechanisms. Our data also indicate that a cell-mediated immune response may play an important role in the pathogenesis of the disease.
Gross
T
T
Department of Dermatology, The Saarland University Hospital, Homburg/Saar, Germany.
Wagner
A
A
Ugurel
S
S
Tilgen
W
W
Reinhold
U
U
D000328:Adult; D000368:Aged; D017252:CD3 Complex / Q000032:analysis; D016827:CD8 Antigens / Q000032:analysis; D005260:Female; D053804:Granzymes; D006801:Humans; D007150:Immunohistochemistry; D016130:Immunophenotyping; D018459:Lichen Sclerosus et Atrophicus / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D008297:Male; D008565:Membrane Proteins / Q000032:analysis*; D008875:Middle Aged; D039102:Poly(A)-Binding Proteins; D011506:Proteins; D016601:RNA-Binding Proteins / Q000032:analysis*; D012697:Serine Endopeptidases / Q000032:analysis*; D000074019:T-Cell Intracellular Antigen-1; D013602:T-Lymphocytes, Cytotoxic / Q000737:chemistry* / Q000473:pathology
D017252:CD3 Complex; D016827:CD8 Antigens; D008565:Membrane Proteins; D039102:Poly(A)-Binding Proteins; D011506:Proteins; D016601:RNA-Binding Proteins; D000074019:T-Cell Intracellular Antigen-1; C071558:TIA1 protein, human; C509213:GZMB protein, human; D053804:Granzymes; D012697:Serine Endopeptidases