TCR gamma delta bearing T lymphocytes infiltrating human primary cutaneous melanomas

In situ immunophenotypic studies show that tumor infiltrating T lymphocytes from six of 11 fresh cutaneous primary melanomas tested contain T-cell receptor gamma delta expressing cells whereas those from 8 metastatic melanomas did not. In three cases these cells represent an unexpectedly high proportion of the lymphocytic infiltrate, ranging from 15 to 25%. This elevated percentage is maintained when tumor infiltrating lymphocytes are propagated in vitro for 2 or 3 weeks in the presence of recombinant interleukin 2 and autologous tumor cells. Functional studies reveal that gamma delta lines or clones developed from lymphocytes infiltrating primary melanoma display, in addition to their natural killer-like activity, a potent autologous tumor cell cytotoxic activity that does not seem to be restricted by major histocompatibility complex gene products.

Identification of a novel 110-kilodalton structure expressed on a subset of T cell receptor-gamma delta-bearing cloned lymphocytes

A small percentage of circulating CD3+ cells express a heterodimeric gamma delta receptor. Most of these cells do not express the surface marker CD4 and only a fraction of them bear CD8 molecules. The specificity and function of TCR-gamma delta are unclear. We obtained a murine mAb produced against an IL-2-dependent human T cell clone defining a novel molecule sTA which is not expressed on resting human peripheral blood CD3+ cells but strongly expressed on a fraction of TCR-gamma delta-bearing clones. Like receptors for growth factors such as IL-2, the sTA Ag is present on clones and cell lines according on the cell cycle. SDS-PAGE analysis of sTA immunoprecipitates from 125I-labeled sTA+ clone lysate demonstrated a single band of molecular mass 110 kDa under reducing conditions. Triggering with anti-sTA mAb did not result in [Ca2+]i mobilization of sTA+ clones. Additionally, the presence of anti-sTA did not alter the cytotoxicity of these sTA+ clones neither against tumor target cells nor against specific PHA blast cells. Interestingly, due to the fact that most sTA+ clones fail to proliferate in response to CD3 triggering, it appears that sTA may serve as a useful marker to study the functional heterogeneity of TCR-gamma delta expressing cells.

Identification of a novel 110-kilodalton structure expressed on a subset of T cell receptor-gamma delta-bearing cloned lymphocytes

A small percentage of circulating CD3+ cells express a heterodimeric gamma delta receptor. Most of these cells do not express the surface marker CD4 and only a fraction of them bear CD8 molecules. The specificity and function of TCR-gamma delta are unclear. We obtained a murine mAb produced against an IL-2-dependent human T cell clone defining a novel molecule sTA which is not expressed on resting human peripheral blood CD3+ cells but strongly expressed on a fraction of TCR-gamma delta-bearing clones. Like receptors for growth factors such as IL-2, the sTA Ag is present on clones and cell lines according on the cell cycle. SDS-PAGE analysis of sTA immunoprecipitates from 125I-labeled sTA+ clone lysate demonstrated a single band of molecular mass 110 kDa under reducing conditions. Triggering with anti-sTA mAb did not result in [Ca2+]i mobilization of sTA+ clones. Additionally, the presence of anti-sTA did not alter the cytotoxicity of these sTA+ clones neither against tumor target cells nor against specific PHA blast cells. Interestingly, due to the fact that most sTA+ clones fail to proliferate in response to CD3 triggering, it appears that sTA may serve as a useful marker to study the functional heterogeneity of TCR-gamma delta expressing cells.

[Treatment of Kaposi's disease]

Several clinical, epidemiological and immunological data support the opportunistic nature of Kaposi's disease. Although the physiopathology of the disease is unknown, its characteristics, and particularly its immunological dependence, have repercussions on treatment which must avoid making the immunological process worse, especially since the proliferation is rarely life-threatening. Recent therapeutic innovations, such as alpha interferon, have failed to bring the expected results which are disappointing in the form associated with the acquired immunodeficiency syndrome. In the classical form of the disease radiotherapy and chemotherapy provide a satisfactory improvement without any side-effect that might threaten the patient's life.