Melanoma tumor-infiltrating lymphocytes derived from four distinct anatomic sites obtained from a single patient: comparison of functional reactivity and melanoma antigen recognition

Tumour-infiltrating lymphocytes and melanoma tumorigenesis: an insight

The presence of tumour-infiltrating lymphocytes (TILs) amid the tumour cells in the stroma and overlying epidermis is a constant feature of melanoma, the deadliest skin cancer. These lymphocytes are mostly cytotoxic T cells (CTLs) that can be propagated in vitro by specific cytokines. Also, they can kill melanoma cells. This specific killing can be abrogated by monoclonal antibodies against CD3, CD8, T-cell receptors (TCRs) and against class I human leucocyte antigens (HLAs). This indicates that these CTLs can recognize the melanoma cells through the TCRs, in an HLA class I-restricted manner. Therefore, these cells and their products both are critical players in T cell-induced melanoma regression and are powerful predictors of survival. This review seeks to examine the characteristics, activation and role of TILs and their associated molecules in melanomas.

Growth and Functional Reactivity of Lymphocytes Obtained from Three Anatomic Compartments in Patients with Non–Small-Cell Lung Cancer (NSCLC)

Non-small-cell lung cancer (NSCLC) claims the lives of both men and women worldwide. In this study, we describe the ability to expand lymphocytes from solid tumor biopsies, pleural fluid, and peripheral blood of patients with NSCLC. While lymphocytes readily expanded from both solid biopsies and pleural fluids, the incidence of obtaining tumor-specific lymphocytes was low. Specific cytolytic and/or cytokine-releasing activity was observed in tumor-infiltrating lymphocytes (TIL) from 3/15 solid tumor biopsies (20%) and 2 of 4 pleural fluid samples (50%). Two of the CTL derived from solid tumor were cytolytic, one being HLA-A2 restricted while the other was either restricted at HLA-A30 or - B18. One of the pleural fluid cytotoxic T lymphocyte (CTL) was also HLA-A2 restricted. Peripheral blood from NSCLC patients was studied using mixed lymphocyte tumor cell cultures (MLTC) as reported previously. Peripheral blood lymphocytes were cultured with allogeneic NSCLC-TC line 29.7, which expressed by gene transfer the lymphocyte costimulatory molecule CD80. Of 9 HLA-A2 patient samples tested, 8 gave rise to lymphocytes, which lysed NSCLC tumor cells expressing HLA-A2 in an major histocompatibility complex (MHC)-restricted fashion. While specific CTL can be generated from all anatomic sites, for clinical trials peripheral blood appears to be the site of choice for obtaining specific precursors.

Self-tolerance to the murine homologue of a tyrosinase-derived melanoma antigen: implications for tumor immunotherapy

The human tyrosinase-derived peptide YMDGTMSQV is presented on the surface of human histocompatibility leukocyte antigen (HLA)-A*0201(+) melanomas and has been suggested to be a tumor antigen despite the fact that tyrosinase is also expressed in melanocytes. To gain information about immunoreactivity and self-tolerance to this antigen, we established a model using the murine tyrosinase-derived homologue of this peptide FMDGTMSQV, together with transgenic mice expressing the HLA-A*0201 recombinant molecule AAD. The murine peptide was processed and presented by AAD similarly to its human counterpart. After immunization with recombinant vaccinia virus encoding murine tyrosinase, we detected a robust AAD-restricted cytotoxic T lymphocyte (CTL) response to FMDGTMSQV in AAD transgenic mice in which the entire tyrosinase gene had been deleted by a radiation-induced mutation. A residual response was observed in the AAD(+)tyrosinase(+) mice after activation under certain conditions. At least some of these residual CTLs in AAD(+)tyrosinase(+) mice were of high avidity and induced vitiligo upon adoptive transfer into AAD(+)tyrosinase(+) hosts. Collectively, these data suggest that FMDGTMSQV is naturally processed and presented in vivo, and that this presentation leads to substantial but incomplete self-tolerance. The relevance of this model to an understanding of the human immune response to tyrosinase is discussed.

Use of cellular and cytokine adjuvants in the immunotherapy of cancer

Cellular and cytokine adjuvants, often immune effector cells and soluble factors, respectively, are supplemental and/or follow-up treatments of human origin for cancer patients who have unsatisfactory clinical responses to conventional chemotherapy, radiotherapy, and surgery. Since many human studies with these reagents are in their infancy, extensive data collection is only now being performed to determine which strategy provides the greatest therapeutic benefit. Research published in the literature since the genesis of this approach to cancer treatment is summarized in this report. Methodologies attempting to generate anticancer responses by provoking or enhancing the patient's own immune system are new compared with the other standard types of cancer treatment. Although a few encouraging human studies can be discussed, many of the most promising techniques are only now being transferred from the laboratory to the clinic. The administration of immune effector cells in combination with immunomodulators, such as interferons or interleukins, often enhances clinical outcome. The literature cited in this report indicate that immune-cell- and cytokine-based therapies hold promise in our attempts to improve the quality and duration of life in those with cancer. With each report reaching the literature, more effective clinical trials are being designed and implemented.