Transfer of foreign DNA into the cells of developing mouse embryos by microprojectile bombardment.

Mouse cells of developing embryos at the 2-4 cell, morula and blastocyst stages, were bombarded by high velocity tungsten microprojectiles. About 70% of developing embryos survived the bombardment. The general embryo structure did not change as a result of the bombardment. Penetration of the tungsten microparticles into the embryo cell nuclei was found at all stages being investigated, and tungsten particle localization on mitotic chromosomes was demonstrated. The total DNA of the mice born from the bombarded embryos was analyzed by dot-blot hybridization and PCR with post-hybridization. The most important results were obtained in experiments with blastocysts. In three cases of blastocyst bombardment, the presence of transferred plasmid DNA (pSV3-neo) was revealed. Transfected cells were shown to be located in the fetal membrane as well as in the embryo. The bombardment of mouse culture cells resulted in their transfection and the production of G418-resistant clones.

[Suppression of the human immunodeficiency virus in cultured cells by 5'-phosphites of 3'-azido-2',3'-dideoxynucleosides]. / Podavlenie virusa immunodefitsita cheloveka v kul'ture kletok 5'-fosfitami 3'-azido-2',3'-didezoksinukleozidov.

5'-Phosphites (5'-hydrogenphosphonates) of 3'-azido-2'-, 3'-dideoxynucleosides are shown to be effective inhibitors of the human immunodeficiency virus (HIV-1) in MT4 cell culture. 5'-Phosphite of 3'-azido-2', 3'-dideoxythymidine was the most active among these compounds and even a little more active as compared to the well-known anti-AIDS drug 3'-azido-2',3'-dideoxythymidine; at the same time 5'-phosphites of 3'-azido-2',3' -dideoxynucleosides with adenine, guanine and cytosine bases were more active than the corresponding nucleosides. The toxicity of all four phosphites was comparatively low and the equimolar mixture of all four phosphites was 2-3 fold less toxic than each of them separately. Data on the decreased toxicity of the phosphite mixture are explained from the viewpoint of a decreased pool disbalance of natural 2'-deoxynucleoside 5'-triphosphates in cells; a significant pool disbalance is developed in the case of 3'-azido-2',3'-dideoxythymidine action.

[Karyological study of the continuous cell lines. Comparative analysis of the Hela and Detroit-6 cell lines]. / Kariologicheskoe issledovanie perevivaemykh kletochnykh linii. I. Sravnitel'nyi analiz linii Hela i Detroit-6.

Comparison of the results of the karyologic analysis of two Hela cell sublines (HeLa1 and HeLa2), obtained from different sources, and of Detroit-6 cell line has shown that all the lines contain marker chromosomes characteristic of the HeLa cell line. Detroit-6 cell line marker chromosomes are similar to markers of the HeLa subline (HeLa1). At the same time, part of marker chromosomes in the two sublines of HeLa cell line (HeLa1 and HeLa2) are different. These data show that HeLa1 and Detroit-6 cell lines are more similar than two sublines of the same HeLa cell line.

[Karyologic study of transplantable cell lines. II. Comparative analysis of lines HEp-2, FL and RH].

A comparative karyologic analysis of three continuous cell lines of different origin (HEp-2, FL and RH) has shown them differing from each other both in the number of chromosomes, and in marker chromosomes. In cultures HEp-2, the modal class consists of cells possessing 58-59 chromosomes, cells in cultures Fl and RH have 60 and 66 chromosomes, resp. Marker chromosomes both similar and not similar, i.e. characteristic of a given cell line only were found in all the investigated cell lines. The data obtained do not exclude a possibility of contamination of studied continuous cell cultires with HeLa cell line.

[Karyologic study of continuous cell lines. IV. Study of human cell lines using the C-method of staining chromosomes]. / Kariologicheskoe issledovanie perevivaemykh kletochnykh linii. IV. Izuchenie linii kletok cheloveka s pomoshch'iu C-metoda okraski khromosom.

With the aid of the C-method of chromosome staining marker chromosomes three classes of human continuous cell lines were studied: 1) HeLa and HeLa-like cell lines (HEp-2, U, KB); 2) non-HeLa cell lines, with type B mobility of glucose-6-phosphate-dehydrogenase (HOS, A-549, A-204); 3) lymphoblastoid cell lines (Raji, Namalva, L-101). Two C-marker chromosomes were observed in two investigated cell lines A-204 and KB, one C-marker chromosome was observed in HEp-2, HeLa, U, A-549, Namalva cell lines; C-markers were absent in HOS and L-101 cell lines. Y-chromosome was found in Raji, A-549 and L-101 cell lines. The C-method of chromosome staining is a simple method, promoting an intraspecific identification of human cell lines.

[Lines of transformed mouse thymus cells. II. Cell morphology, karyology, ultrastructure and growth in vitro and in vivo]. / Linii transformirovannykh kletok timusa myshi. II. Morfologiia, kariologiia, ul'trastruktura, rost kletok in vitro i in vivo.

Morphology, fine structure, karyology and growth of intrathymus pre-T-cell cultures (TC.SC-1/1.1 and TC.SC-1/2.0) were studied both in vitro and in vivo. The cultures were induced by injecting to mice a supernatant enriched with interleukin 2. The results obtained confirm the malignant transformation of cells of the lines obtained and the involvement of endogenic lymphotropic viruses in this process. The lines obtained are defective in hypoxanthine phosphoribosyltransferase. This property may serve as a basis for their use in hybridoma technology.

[Karyological characteristics of L cells and the identification with them, of the antigen of persisting Japanese encephalitis virus]. / Kariologicheskaia kharakteristika kletok L i identifikatsiia v nikh antigena persistiruiushchego virusa iaponskogo éntsefalita.

The immunofluorescence procedure revealed the virus-specific Japanese encephalitis virus antigen in latently infected L cells as well as differences in the percentage of antigen-positive cells and in the localization of the virus-specific antigen under conditions of acute, chromic, and latent infection and in the period of activation of the latent state of the virus at 28 degrees C. Karyological studied demonstrated no marked differences between persistently infected and original lines.

[Marker chromosome study of murine cell line tumor tissues]. / Issledovanie markernykh khromosom opukholevykh tkanei myshinykh kletok.

By C-method of chromosome staining three transplantable murine tumor lines passaged in vivo were studied. Marker chromosomes were discovered in all cell lines under observation. The previously described marker chromosomes B and C were found in transplantable Ehrlich ascites carcinoma cells, acrocentric chromosome with additional C-band --in cells of line C-37, acrocentric chromosome with double quantity of subcentrometric heterochromatin in cells of line TG-180. The data obtained make it possible to distinguish the lines under study by C-method of chromosome staining.

[Marker chromosome study of green monkey cell cultures]. / Issledovanie markernykh khromosom kul'tur kletok zelenoi martyshki.

An investigation of three continuous green monkey cell lines by the C-method of differential staining of chromosomes revealed one marker chromosome in BSC-1 cell line and three marker chromosomes in Vero cell line. Two variants of CV1 cell line (I and II) were sharply different both in the modal class and in the marker chromosomes: a great number of chromosomes and two S-marker chromosomes were characteristic of line I CV1; absence of C-marker chromosomes and the peridiploid chromosome set were characteristic of line II CV1. These marker chromosomes are enough stable and may be used for the identification of the given cell lines.

[Marker chromosomes of murine cell lines]. / Markernye khromosomy nekotorykh linii myshinykh kletok.

Using the C-method of chromosome staining four marker chromosomes were revealed in the transplanted murine line SC-1, one comparatively rare marker chromosome was shown in RAG line, small marker chromosomes occurred almost in all cells of RVP3 line. Marker chromosomes found in the studied lines by the C-method of chromosome staining make it possible to distinguish these lines from each other.

[Karyological analysis of hybridoma lines producing monoclonal antibodies to viral antigens]. / Kariologicheskii analiz gibridomnykh linii, produtsiruiushchikh monoklonal'nye antitela virusnym antigenam.

The number of Hybridomes obtained from various sources rapidly increases at present. Clones producing monoclonal antibodies to influenza virus A/USSR/090/77 and to VEE-230 are generated in the laboratory of the Institute of Virology (Academy of Sciences of the USSR). The present work is devoted to the study of Hybridome karyotype by means of C-method for chromosome staining with the aim to reveal specific characteristics of these lines. Results of the investigation have shown that the count of chromosomes together with an examination of their C-staining picture permit proving a hybrid nature of the clones and identifying various Hybridomes by chromosome markers.

[Karyological study of the HTR-5 cell line]. / Kariologicheskoe issledovanie kletochnoi linii ChETR-5.

A karyologic study of the human fibroblasts transformed by the SV-40 virus at the level of the 15th subculture shows that this line (HTR-5) consists mainly of cells with a pseudodiploid karyotype. The cells of the investigated line contain marker chromosomes characteristic for this cell culture.

A micro-dissection approach for isolation of NotI linking clones from regions frequently deleted in RCC and SCLC.

We demonstrate that micro-dissection can be used for isolating NotI linking clones from the human 3p21-pter region. This approach is an improvement to positional cloning techniques, since NotI linking clones are directly linked with genes.