Comparison of T suppressor factors from tumour-bearing mice and mice immunized with a monoclonal anti-idiotypic antibody

Abstract

Certain dosage schedules of a monoclonal anti-idiotypic antibody (related to a murine bladder carcinoma) were found to induce suppressor factor production by syngeneic mice. This suppressor factor resembled the factor from tumour-bearing mice with respect to idiotype specificity, possession of molecular markers (reactive with anti-IJ and B16G antibodies) and production by Lyt2+IJ+ T cells in spleen cell cultures. The two factors differed with respect to Igh restriction in an in vitro assay (leucocyte adherence inhibition) and ability to suppress the induction of delayed-type hypersensitivity to tumour antigen.

Effects of anti-idiotype vaccine on tumour growth and on production of soluble factors modulating cell-mediated immunity in vitro

“…The administration of antigen has similar consequences, and these depend in both contexts on size and number of doses and routes of injection. Whereas in previous publications we stressed the relationship of MAIA 21D9 to the induction of cell-mediated anti-tumour immunity and specific suppressor factors [7,13], we have shown here that other soluble factors may also be induced and may have effects on tumour growth.…”

“…The cells primarily involved in producing the suppressor factors were shown earlier to be Lyt2 + IJ + T cells in spleen cell cultures [7]. In contrast, depletion of Lyt2+ cells in the present work did not prevent the production of enhancing factor.…”

“…As described briefly above, the injection of mice with particular amounts of MAIA as single doses induced Table 1 suppressor factor formation [7]. These factors were found in SCCS from injected mice and were detected by their suppression of LAI assays.…”

“…[15] resulted in inhibition of tumour growth under cerrain dosage schedules, whereas other schedules accelerated growth of tumours. Similarly, Dunn et al [4] found that the anti-tumour response of rats treated with MAIA related to two different rat sarcomas was dependent both qualitatively and quantitatively on the mode of immunization of the rats.Using an internal-image MAIA (Ab2~) related to a transplantable murine bladder carcinoma, which was found in earlier studies [6,13] to mimic a tumour-associated antigen by inducing specific cell-mediated anti-tumour immunity, we showed, in a previous paper [7], that the injection of mice with certain doses of MAIA induced the formation of potent suppressor factors. These factors specifically suppressed leucocyte-adherence inhibition (LAI) assays in vitro and delayed-type hypersensitivity (DTH) reactions in vivo, and resembled the suppressor factors produced during tumour growth in some ways but not in others.…”

“…Monoclonal anti-IJ d, previously shown to react with IJ-bearing suppressor factors in the same tumour system [7], is shown hexe to be unable to bind the enhancing factor (Table 4). Anti-IJ k antibodies were also unreactive, as expected, since the SCCS was prepared ffom BALB/c mice (H-2d).…”