[Comparative study of the influence of renal endogenic factors on the proliferation activity of epithelial cells].

The proliferation activity of monolayer culture of Madin Darby Canine Kidney (MDSK) cells is suppressed by a thermostable protein factor of renal tissue of white rats and of humans. Under the influence of renal factors (RF), a decrease in cell number, and suppression of DNA synthesis and mitotic activity in MDCK cells occur. The inhibition of proliferative activity of cultured cells under the influence of RF was substantiated also by MTT assay. It was established that the inhibitory influence of RF is stipulated by suppression of RNA synthesis. It follows that RF may inhibit division of MDCK cells via suppression of gene expression in G1-phase. Similar factors were obtained from renal cells of different systematic groups of organisms (snail, frog, fish, pigeon, guinea pig, swine).

[The preclinical assessment of the activity and pharmacological action of native human interleukin-2]. / Predklinicheskaia otsenka aktivnosti i farmakologicheskogo deistviia nativnogo interleikina-2 cheloveka.

It was demonstrated in in vivo and in vitro experiments that interleukin-2, obtained by cultivation of donor lymphocytes and purified by gel filtration, induces the production of mouse and human killer lymphocytes possessing high cytolytic activity against tumor cells. Interleukin-2 does not cause irreversible changes of the physiological and morphologic indices of vital activity in mice.

[Cytotoxicity of the lymphocytes of melanoma patients against autologous tumor cells and its in vitro enhancement]. / Tsitotoksichnost' limfotsitov bol'nykh melanomoi protiv autologichnykh opukholevykh kletok i ee usilenie in vitro.

Specific cytolytic and natural killer activity of peripheral blood lymphocytes was studied in 12 patients with metastatic melanoma. The cytolytic activity of lymphocytes against autologous tumor cells was found in 8 patients. It appeared significantly enhanced by pretreatment of tumor target cells with concanavalin A (Con A). The natural killer activity in all the patients was 2-10 times as high as the specific cytolytic activity. Stimulation of patient lymphocytes with autologous tumor cells or with the mixture of lymphocytes from 5 allogeneic donors induced the generation of highly active T killers possessing natural killer and specific antitumor cytolytic activity.

[Comparative characteristics of human interleukin-2 preparations isolated from various sources]. / Sravnitel'naia kharakteristika preparatov interleikina-2 cheloveka, poluchennogo iz raznykh istochnikov.

Interleukin-2 (IL-2) was isolated from donor peripheral blood lymphocytes and from JURKAT T-lymphoma cells. The purification procedure including gel filtration on DEAE and CM-Sephadex resulted in a 400-fold increase of the enzyme specific activity. It was shown that optimal proliferation of T-lymphocytes occurs upon consecutive treatment of cells with phytohaemagglutinin and IL-2 as well as in the presence of a serum. The properties and procedure of isolation of the long proliferating line of IL-2-dependent T-cells B-5 were described. Proliferation of B-5 cells completely depended on the presence of IL-2 in the medium, although long-term proliferation occurred upon periodic stimulation of cells with the antigen (allogenic lymphocytes). In the absence of IL-2 B-5 cells decay within 36 hours. The perspective uses of IL-2 prepared from the cultural fluid of human peripheral blood lymphocytes for adoptive immunotherapy of tumours and the applicability of IL-2-dependent B-5 cells for testing the activity of IL-2 preparations from various sources are discussed.