[Immunocytophotometric and cytogenetic analyses of T-lymphoblastoid cell lines in experimental HIV Infection].

The accumulation of viral proteins p24 and gp41 in MT-4 cells was shown to occur asynchronously. No increase in the number of polydiploid cells, no polyploid mitoses or chromosome defects were found indicating the antiproliferative effect of HIV on MT-4 cells. A cyclic pattern of the infection course was observed in infected Jurkat-tat cells.

[Changes in the gene expression of the hepatitis B virus in PLC-PRF-5 cells of human hepatocarcinoma during their acquisition of drug resistance].

Mutant clones of hepatocarcinoma cell line PLC-PRF-5 containing integrated hepatitis B virus genome were derived by multistep selection for resistance to some toxic agents. These clones were found to display various stages of cell differentiation according to growth rate, ability to synthesize alpha-fetoprotein, to grow in semisolid medium and to cloning in agar. In the majority of the clones with higher stages of differentiation the expression of HBsAg gene was demonstrated to be increased as compared to the original line, and in some of these clones the expression of silent HBcAg was activated.

[The use of DNA hybridization in situ for identifying chromosomal rearrangements in the karyotyping of cell lines].

A complex karyological analysis of three human cell lines (PLC-PRF-5, MT-4 and U937) was carried out that involved traditional methods of G-, C-banding and silver staining, in addition to the in situ hybridization technique using 4 alpha-satellite DNA probes: DNA specific for centromeric regions of chromosome 11, 6, 13, and 21, and 14 and 22. The application of this additional method allowed to identify, prove or detalize the structure of 13 markers in PLC-PRF-5 cells, 1 marker in MT-4 cells, and 3 markers in U937 cells. The results show that the in situ hybridization method would be successful in cell line karyotyping for a more objective identification of some markers difficult for analysis.

[Nature of the silver staining and association of acrocentric chromosomes in normal and leukemic human cells].

Silver staining and acrocentric chromosome association (ACA) patterns were investigated in bone marrow cells as well as in peripheral blood cells (cultures with or without PHA) from 39 patients with chronic myelocytic leukemia (CML), including 20 cases being in blastic phase (BP CML), and 51 patients with acute leukemia (AL). Bone marrow cells and PHA-stimulated peripheral blood lymphocytes (from 10 and 17 healthy donors, respectively) were used as a control. The frequency of ACA in metaphases from bone marrow cells of all the above groups of patients was shown to be decreased compared to that in PHA-stimulated lymphocytes.

[Determination of estradiol-17 beta receptors in tumorous breast tissue as an index of the hormonal dependence of the tumor].

To judge the hormone-dependence of mammary tumors the technic of tissue sections was employed, which were examined for the presence of oestradiol-17 beta receptors. Under examination were 192 patients, 78 of them being in their reproductive age and 14 menopausal patients. Oestradiol-17 beta receptors were found in the tumor material from 42.