Gamma delta T lymphocytes in oriental cutaneous leishmaniasis: occurrence and variable delta gene expression.
It has been suggested that T lymphocytes expressing gamma delta T-cell receptors could play an important role in defence against some intracellular infectious pathogens. The present study was undertaken to characterize the occurrence and variable delta gene expression of T lymphocytes expressing the gamma delta T-cell receptor in oriental cutaneous leishmaniasis. Eleven cases of oriental cutaneous leishmaniasis were investigated by immunohistological analysis using an alkaline phosphatase-anti-alkaline phosphatase (APAAP) technique. In three cases, we observed an increased percentage of gamma delta T cells (about 20% of CD3+ cells). In these cases gamma delta T cells generally expressed the V delta 2 segment, and only rarely the V delta 1 gene product. V delta 2+ cells were predominantly localized in the dermis, and were virtually absent in the epidermal compartment. The rare gamma delta T cells observed in the epidermis were almost exclusively V delta 1+. This study demonstrates that an increase of gamma delta T cells may be found in oriental cutaneous leishmaniasis, although it is not a constant feature of the disease. The finding of a preferential expansion of the V delta 2 subset suggests that this subpopulation of gamma delta T cells might be selectively involved in the recognition of Leishmania antigens. The distinct compartmentalization of gamma delta T-cell subpopulations indicates that these subsets may recognize distinct sets of antigens.
Unit of Dermatology, Royal Postgraduate Medical School, Hammersmith Hospital, London, U.K.
M
M
Alaibac
G
G
Harms
K
K
Zwingenberger
J
J
Morris
R
R
Yu
A C
AC
Chu
D000953:Antigens, Protozoan / Q000032:analysis; D017252:CD3 Complex / Q000032:analysis; D015870:Gene Expression; D006801:Humans; D007124:Immunoenzyme Techniques; D016773:Leishmaniasis, Cutaneous / Q000235:genetics* / Q000276:immunology / Q000473:pathology; D007958:Leukocyte Count; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000032:analysis*; D013601:T-Lymphocytes / Q000276:immunology
D000953:Antigens, Protozoan; D017252:CD3 Complex; D016692:Receptors, Antigen, T-Cell, gamma-delta