Ascitic Growth of a T Cell Lymphoma in Mice Alters the Humoral and Cellular Immune Response to Exogenous Antigens.

The effect of the ascitic growth of Dalton's lymphoma (DL), a T cell lymphoma, on the immune responses of the host mice to exogenous antigens, with respect to the humoral response, delayed-type hypersensitivity (DTH) response and the antigen-presenting ability of macrophages was investigated. The humoral immune response to sheep red blood cells (SRBC) as well as the antigen-presenting ability of macrophages (with keyhole limpet hemocyanin as the standard antigen) in the DL-bearing mice were consistently higher than in the normal mice, although the magnitude showed a decline during later tumor stages. However, the DTH response to SRBC was suppressed in the DL-bearing mice compared with the response in the normal mice. The possible mechanisms are discussed. In vivo administration of FK565, a synthetic biological response modifier, enhanced the humoral immune response as well as the antigen-presenting ability of the macrophages in the normal and early DL-bearing mice, whereas these immune responses n the later tumor-bearing animals were found to be nonresponsive to FK565 treatment. In contrast, the DTH response in the normal as well as in the DL-bearing mice was suppressed on FK565 administration. This is the first study of its kind regarding the effect of the ascitic growth of any T cell lymphoma on various aspects of the immune response to exogenous antigens and the correlation thereof with an immuno-modulator. Copyright © 1997 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]