Distribution of lymphocytes bearing TCR gamma/delta in cutaneous lymphocytic infiltrates

A monoclonal antibody to the recently characterized T lymphocyte expressing a T cell receptor bearing gamma and delta chains (TCR gamma/delta) was applied to 60 biopsy specimens spanning a wide range of diagnoses and containing a variable number of T lymphocytes. TCR gamma/delta+ cells were not enriched in the tissues examined, representing between 0-5% of the total CD3 positive T lymphocyte population. TCR gamma/delta+ cells were identified in 27 cases (45%). The distribution of the TCR gamma/delta-bearing cells was remarkable for preferential stratification at upper cutaneous levels, within the epidermis and papillary dermis in some cases of mycosis fungoides. Benign infiltrates lacked a similar pattern. The role of TCR gamma/delta+ cells is uncertain. The data do not reveal a consistent number or distribution of these cells in cutaneous infiltrates.