Key problems of antitumor immunity and glycoconjugates]

Two key problems of the antitumour immunity are considered: 1) very rapid changing of tumour-associated antigens; 2) tumour immunosuppression. Carbohydrate structures of the tumour-associated antigens (mainly glycoconjugates) are changing much more rapidly (hours, days) than the clones of antitumour T-killers proliferate. It is stated that the fundamental question of the nature of the glycoconjugate and endogenous lectin changing is not sufficiently studied. The endogenous lectins of the lymphocyte and macrophage surface are an old recognizing system responsible for a natural cell resistance to the tumour. Stimulation of this system by means of bacterial and syngeneic glycoconjugates is a promising direction in the tumour immunotherapy. Concerning the second aspect, the data are summarized according to which tumour cells produce inhibiting factors, including glycoconjugates, that suppress both proliferation and function of lymphocytes and macrophages. Developing the methods of rehabilitation of the immune system cells with the use of activating glycoconjugates and cytokines is the second important trend in the tumour immunotherapy.