Production of IL-2 fusion antibodies and determination of their biological activity

Interleukin 2 is a small cytokine with many important immune functions. It is used mainly as a T cell growth factor, but it also acts on other immune cells, especially NK and NK-T cells. IL- 2 at higher doses induces the differentiation and proliferation of the cell population of effector and memory T cells, which are characterized by cytotoxicity and are able to effectively defend the organism against pathogens and / or tumor cells. In contrast, low-dose IL-2 stimulates the Treg population, which suppresses immune responses and helps prevent autoimmune diseases. However, in cancer therapy, stimulation of this cell population is undesirable. Because free IL- 2 is toxic to the body at high doses, strategies have previously been proposed to potentiate the biological effect of IL-2. One of the most promising appears to be the single-stranded recombinant fusion construct, where IL-2 is covalently linked via an oligopeptide linker to an anti-IL-2 monoclonal antibody (mAb). Based on the findings of the studies of IL-2 / anti-IL-2 mAb immunocomplexes, this immunocytokine (IC) could provide significant therapeutic benefits in vivo, as compared to free IL-2, especially very robust strengthening of biological activity, selective stimulation of specific cell populations according to the selected antibody and..