Effect of release-active anti-interferon-gamma antibodies on the course of the tumor process in in vivo experimental models

Abstract

Interferon-gamma (IFNγ) plays an important role in antitumor immunity; however, in some circumstances, it may also favor tumor immune evasion. Released-active (RA) anti-IFNγ antibodies (Abs) are able to induce conformational changes in the IFNγ molecule and to facilitate its receptor binding, which results in enhanced production of this cytokine. The aim of the present study was to evaluate the effect of RA anti-IFNγ Abs on the tumor growth in models of melanoma and carcinosarcoma. Methods. The ability of anti-IFNγ RA Abs to influence the tumor growth was evaluated in the models of melanoma B16 in mice and Walker 256 carcinosarcoma in rats. Results. The exposure of mice with IFNγ-sensitive melanoma B16 to the tested drug did not result in stimulation of tumor growth and metastasis. RA anti-IFNγ Abs also did not affect the tumor size in the rat model of Walker 256
carcinosarcoma but significantly inhibited the hematogenous metastasis. Conclusion. In the present study, no stimulation of the tumor process and metastasis by RA anti-IFNγ Abs were found.