[Hemopoietic precursor cells in the intima of the atheromatous human aorta]. / Gemopoéticheskie kletki-predshestvenniki v intime ateromatoznoi aorty cheloveka.

Granulocyte-macrophage progenitor cells (CFU-GM) were found in the intima of human atheromatous aorta. Granulocyte-macrophage colonies were recovered on the 14th day of culturing of intimal cells suspensions on agar. Medium conditioned by normal leukocytes in the presence of phytohaemagglutinin was used as a source of the colony-stimulating factor. Grossly normal and atheromatous intima contained different number of CFU-GM. No GM were recovered from fibrous plaques. By light and electron microscopies, the injured aortic intima contained the clusters of blood-born cells that were at various stages of granulocytopoiesis (including blasts and mature cells) and poorly differentiated lymphocyte-like cells. The results obtained suggest that in human aortic intima proliferation and differentiation of CFU-GM occur at early stages of atherogenesis, prior to fibrous plaque formation.

[Quantitative evaluation of the phagocytic activity of endothelial cells in culture]. / Kolichestvennaia otsenka fagotsitarnoi aktivnosti kletok éndoteliia v kul'ture.

The phagocytic activity of endothelial cells (EC) from human umbilical vein was analysed quantitatively in primary culture. EC were incubated with fluorescent carboxylated microspheres (FCM) and the intensity of fluorescence was measured on spectrofluorimeter. It was found that EC phagocyted actively only FCM of limited diameter (not more than 0.26 mu). The most intensive phagocytosis occurred in the first 60 min of the experiment, the following incubation with FCM did not influence significantly the number of phagocyted particles but increased nonspecific binding. High doses of FCM stimulated phagocytosis within EC. The phagocytic activity of EC depended on the growth stage: it was maximum in proliferated cells and sharply decreased in confluent cultures. This method may be useful for the comparison of phagocytic activity of different cell types, as well as for drug testing.

[Change in the nonspecific cytotoxic activity of the lymphocytes depending on the method of their isolation]. / Izmenenie nespetsificheskoi tsitotoksicheskoi aktivnosti limfotsitov v zavisimosti ot metoda ikh vydeleniia.

The authors present the results of comparative study of nonspecific cytotoxicity of lymphocytes, obtained by different methods, on the cells of cultivated melanoma. The lymphocytes were obtained from defibrinated and heparinized blood of normal donors on a column made of cotton and of phycoll-verographine mixture. Lymphocytes obtained on the latter proved to possess greater cytotoxicity than those obtained on the former. Lymphocyte suspensions from the column, containing platelets were less toxic than lymphocyte suspensions without any platelets. Lymphocytes obtained on the column were more toxic against the melanoma cells of the 22nd--29th passage than against the cells of the 35th--41st passage. This regularity was more pronounced for lymphocyte-platelet suspensions.