Tumor necrosis factor has traditionally been thought to have direct cytostatic and cytotoxic properties with little or no direct immunomodulatory activity. We report here that tumor necrosis factor is able to activate macrophages both in vitro and in vivo and can increase a mixed lymphocyte response and act as an adjuvant for both T- and B-cells in vivo. Adjuvant activity in T-cells occurred in conjunction with the administration of a suboptimal syngeneic tumor cell vaccine. In addition, tumor necrosis factor demonstrated a potent dose-dependent effect on bone marrow stem cell number, dramatically depressing cellularity and thus total stem cell number. An appreciable interval is required for recovery from such stem cell depletion. Therefore, the study of the therapeutic activity of tumor necrosis factor must include a consideration of its immunomodulatory properties.

1

This research was sponsored by the Biological Resources Branch, Biological Response Modifiers Program, Division of Cancer Treatment, National Cancer Institute, Department of Health and Human Services, under Contract N01-23910 with Program Resources, Inc. The contents of this publication do not necessarily reflect the views or policies of the Department of Health and Human Services, nor does mention of trade names, commercial products, or organizations imply endorsement by the United States Government.

This content is only available via PDF.
©1988 American Association for Cancer Research.
1988
Cancer Research, Inc.