In vivo assessment of tumor-induced nonspecific suppression of contact sensitivity

Summary Normal BALB/c mice were assessed for 2,4-dinitrofluorobenzene (DNFB)-induced contact sensitivity following adoptive transfer of macrophages (Mo). T cells, or their derived products, from normal or tumor-bearing hosts (TBH). Contact sensitivity (CS) was measured by a quantitative radioisotopic ear assay, a total in vivo system based on localization of IP-injected iodinated human serum albumin ([¹²⁵I]HSA) in the DNFB-challenged ear. Adoptive transfer of low or high doses of TBH T cells or their derived supernatants into normal recipients suppresed their responsiveness, while Mo supernatants enhanced it. Moreover, in all cases adoptive transfer of TBH cells or supernatants resulted in a lower CS response than did their normal counterparts. These results further corroborate our previous in vitro data indicating that T cells, or Mo and T cell soluble products, possess immunoregulatory capabilities in vivo.Abbreviations DNFB 2,4-dinitrofluorobenzene - TBH tumor-bearing host - Mo macrophages - ¹²⁵I-HSA iodinated-human serum albumin - CMI cell-mediated immunity - CS contact sensitivity; Ig, immunoglobulin - C complement