[The effect of interferon preparations on the ultrastructural organization of Legionella pneumophila]. / Vliianie preparatov interferona na ul'trastrukturnuiu organizatsiiu Legionella pneumophila.

The influence of the preparations of interferon on morphological changes in L. pneumophila on the ultrastructural level has been studied. Disturbances in the ultrastructure of L. pneumophila result from the direct bactericidal action of interferons without any interference of immune mechanisms. These disturbances are manifested by damages in the cell wall, plasma membrane, nuclear and ribosomal apparatuses of microbial cells. Leukinferon exhibits pronounced anti-Legionella activity, both in vitro in a liquid culture medium and in ovo, than reaferon.

[The interaction of Legionella pneumophila with different types of cell cultures and the effect of interferon preparations on this process]. / Vzaimodeistvie Legionella pneumophila s razlichnymi tipami kletochnykhkul'tur i vliianie na étot protsess preparatov interferona.

The interaction of L. pneumophila with lymphoblastoid cell cultures H9 and H9/IIIB and epithelial cell cultures HEp-2 mutual influence have been noted. L. pneumophila penetrates into cells HEp-2 and multiplies there due the so-called "spin phagocytosis". The study of the influence of the preparations of interferon, Leukinferon and Reaferon, on the adhesive capacity of bacteria and their penetration into eukaryotic cells has revealed that the preliminary treatment of both bacteria and cells HEp-2 with the preparations of interferon prior to their infection with Legionella leads to a decrease in the number of microorganisms associated with cells.

[The protective properties of different Legionella antigens in experimental Legionella infection]. / Izuchenie protektivnykh svoistv razlichnykh antigenov legionell pri éksperimental'noi legionelleznoi infektsii.

The protective properties of Legionella antigenic preparations were studied on guinea pigs with experimental Legionella infection. Preliminary immunization of guinea pigs with serotypic antigen, cytolysin, as well as live or formalin-treated Legionella cells, did not protect the animals from the subsequent aerogenic infection with 10(5) colony-forming units of virulent L. pneumophila. Immunization with the main outer membrane protein ensured the survival of 70% of the animals and inhibited the proliferation of the infective agent in the lungs of guinea pigs subjected to aerogenic infection with 10(5) colony-forming units of virulent L. pneumophila. The data obtained in this study indicate that the main outer membrane protein of L. pneumophila is capable of stimulating protective immunity.

[The action of interferon preparations on strains of Legionella of various serogroups and species]. / Deitsvie preparatov interferona na shtammy legionell razlichnykh serogrupp i vidov.

The action of different preparations of interferon on Legionella strains has been studied in vivo and in vitro. The preparations of leukinferon at a concentration of 500 international units (I.U.) and reaferon at a concentration of 10,000 I.U. have been found to produce an inhibiting effect on Legionella strains in vitro, in a medium with carbon-yeast agar. Leukinferon at a concentration of 125 I.U. suppresses the growth of L. pneumophila also in a liquid medium. The preparation of leukinferon at a minimal concentration of 100 I.U. has been found to suppress the development of lethal infection in chick embryos infected with L. pneumophila strain Philadelphia 1.

[Mitogenic effect of Legionella pneumophila: the ratio of proliferating T- and B-cells changes after immunization]. / Mitogennoe deistvie Legionella pneumophila: sootnoshenie proliferiruiushchikh T- i B-kletok izmeniaetsia posle immunizatsii.

The splenic lymphocyte proliferative response of guinea-pigs immunized with L. pneumophila antigen (ALP) was studied. The immune animals were shown to express enhanced reactivity in response to E. coli lipopolysaccharide, as compared to the controls, while the response to concanavalin A was markedly decreased. After 3 days in the culture ALP induced a significant nonspecific lymphocyte transformation that was expressed to a similar degree in both experimental and control group. However, after a 5-day incubation ALP induced a specific proliferative response of the immunized guinea-pig splenocytes. The experiments on fractionation by passing through the column with nylon wool revealed that T cells are activated in non-immunized guinea-pigs. The results obtained prove that T cells mediate the immune response to ALP in guinea-pigs.