Immunological assessment of renal cancer patients as evaluated by the lymphocyte adherence inhibition test

Interferons and interleukins in metastatic renal cell carcinoma

Renal cell carcinoma is diagnosed frequently when it already has metastasized. The use of immunotherapy has provided a new source of drugs to be used in the therapy of renal cell carcinoma. Interferons were the first biologics to be evaluated demonstrating a response rate of 10-30 percent. The second cytokine to be actively developed was interleukin-2, a T-cell growth factor which demonstrated activity in patients with renal cell carcinoma of 20-30 percent alone or in combination with LAK cells and other cytokines (such as interferons and tumor necrosis factor). Biologic response modifiers such as interferons and interleukins alone and in combination with other drugs have opened a new era in the therapy of renal cell carcinoma. Future development of other cytokines may pave the way for higher response rates with durable duration for this disease.

Cytotoxic in vitro function in patients with metastatic renal cell carcinoma before and after alpha-2b-interferon therapy. Effects of activation with recombinant interleukin-2

In this study the characteristics of the cytotoxic function in a series of patients with metastatic renal cell carcinoma (RCC) were analyzed and the possibility of modulating this capacity in vitro with the use of biologic response modifiers (BMR) such as alpha-interferon (alpha-IFN) and recombinant interleukin-2 (rIL-2) was verified, with the ultimate goal of providing a rationale for a therapeutic approach to this disease with these molecules. Peripheral blood mononuclear cells (PBMC) of patients with advanced RCC were tested for natural killer (NK) and lymphokine-activated killer (LAK) activity both before and after alpha-IFN therapy. In addition, surface markers of unstimulated and stimulated cells were analyzed and in vitro assays were performed to determine the proliferative capacity in response to the stimulus with rIL-2. During an evaluation before treatment, defective NK activity was observed that could be corrected by incubating the cells with rIL-2. In these subjects, LAK cells could be consistently generated after PBMC were activated with this cytokine in vitro. No changes in NK and LAK activity were found after alpha-IFN therapy. In contrast, treatment with alpha-IFN affected the proliferative response of PBMC to rIL-2, and a significant decrease in this in vitro capacity was observed during follow-up. The ability to restore NK activity and obtain an adequate LAK cytotoxicity from the PBMC of patients with RCC supports a therapeutic approach with BRM. However, the fact that this type of treatment affects the proliferative response of PBMC to rIL-2 must be considered when clinical trials are designed for patients with RCC.

Measurement by leukocyte adherence inhibition of autosensitization of cancer patients to myelin basic protein

In vitro cell-mediated immunity was assayed by leukocyte adherence inhibition (LAI) to determine the extent of autosensitization to myelin basic protein (MBP). Leukocytes from 123 cancer patients, 16 patients freed of cancer, 135 patients with benign disease, and 26 patients with destruction of nervous parenchyma were tested. Most patients with cancer reacted to MBP: 92%, 93%, 82%, 78%, 75% and 62% for pancreatic, colonic, esophageal, lung, ovarian and breast. Few patients with benign diseases reacted to MBP. Patients with multiple sclerosis (MS) were sensitized to MBP, but patients with other nervous tissue injury did not react to MBP. Cancer patients did not remain sensitized to MBP once they were freed of their cancer. The LAI assay is a straightforward method of measuring cellular autosensitivity to MBP. In the population of patients tested, autosensitivity to MBP was confined, except for MS, principally to cancer patients.