[A surface membrane study of human cell lines with different interferon sensitivities].

A comparative study of surface membranes of human cell J-96 and J-48 cultures with different sensitivity to alpha/beta interferon (IF). Reduced sensitivity of J-41 cells to IF-alpha/beta was found to be accompanied by a loss of highly specific receptors for IF-alpha, the lack of changes in the cell surface structures upon treatment with IF-alpha/beta, reduced intensity of cell fusion upon successive treatment with IF and polyethylene glycol. The results are discussed in connection with the observed changes in the activity of superoxide dismutase in J-96 and J-41 cell lines after treatment with IF.

[Activity of human natural killer cells against target cells possessing different sensitivity to interferon].

The cytotoxic activity of peripheral blood natural killers (NK) against target cells (TC) J-96 and L-929 with high sensitivity to interferon (IFN) action, J-41 and MCB resistant to IFN action and line K-562 labelled by H3-uridine was studied in 14 hrs cytotoxic test. It has been shown that human TC J-96 didn't differ from the J-41 in their sensitivity to NK cytotoxicity and they are strongly resistant to NK than TC K-562. The murine TC L-929 as the human TC didn't differ from the MCB in their sensitivity to NK lysis and had also the same sensitivity to NK as the K-562 cells.

[Interferon-specific cellular receptors in cultured human cells, differing in sensitivity to alpha-interferon].

The interferon-specific cellular receptors in human cells cultures differing in sensitivity to alpha-interferon have been studied. The J-41 cells resistant to alpha-interferon are practically devoid of receptors highly specific to alpha-interferon. The coefficient of equilibrium and the number of receptors analyzed after Scatchard for J-96 culture of cells are 15.

[Production of inhibitors of interferon action by cell lines sensitive and insensitive to the antiviral action of interferon].

The capacity of a number of human and murine cell cultures to produce, upon virus induction of interferon synthesis, low molecular admixtures inhibiting interferon antiviral activity was studied. The cells resistant to interferon were found to be 8-16 times as active producers of these admixtures as sensitive cells. A possible role of the production of these admixtures in functional, i.

[Ratio of the antiproliferative action of interferon to the degree of purity of the preparation].

The antiproliferative (AP) action of human leukocytic interferon (HLI) of varying degrees of purification was studied and compared in cultures of human cells differing in interferon sensitivity. The concentrated and purified preparations of HLI suppressed the incorporation of 3H-thymidine and mitotic activities of the cultures sensitive to HLI of the cells, affecting, but insignificantly, the proliferation of the resistant cell culture. Poorly purified HLI suppressed the proliferation of both cell types.

[Stability of C-band heterochromatin polymorphism in 2 transplantable human cell lines differing in sensitivity to Coxsackie virus B3].

Heterochromatin of chromosomes is studied by means of a C-banding technique for the J-96 line of human cells, which is susceptible to enteroviruses and for the J-41 cell line derived from this culture and possessing high specific resistance to Coxsackie B viruses. The data obtained demonstrate stability of variform C-heterochromatin of chromosome pairs 1, 9 16 and certain marker chromosomes in the course of long-term cultivation.

[Karyological characteristics of the transplantable human cell line J-96, susceptible to Coxsackie B3 virus, and of its derived subline J-41, specifically resistant to this virus].

The paper is concerned with comparative cytogenetic studies of human cell line J-96 and subline J-41 derived from it. Application of G-, R- and C-techniques for differential staining of chromosomes made it possible to determine both numeric and structural changes in chromosomes of the resistant subline as compared to the initial one. The mechanisms contributing to a decrease in the normal chromosome number and to appearance of new marker chromosomes in the resistant subline cells are discussed as well as the possible relation of the found chromosome changes to the loss of cell sensitivity to the Coxsackie B3 virus.

[Recovery of the sensitivity of J-41 cells to Coxsackie B3 virus by treatment with exogenous alkaline phosphatase].

It has been shown that injection of G-41 cell cultures, deficient as regards alkaline phosphatase and resistant to Coxsackie B3 virus, in conjunction with exposure to an alkaline phosphatase preparation from the calf intestine results in virus reproduction. Depending on the dose administered and multiplicity of infection there occur either complete destruction of the monolayer or death of some cells with the development of cytopathic changes specific for Coxackie virus.

[Karyotype change in human cell cultures in the process of the reversion of Coxsackie B virus sensitivity].

The study was done on a subline of cells reverting to sensitivity to Coxsackie B3 virus after treatment of J-41 cells resistant to this virus with a homogenate prepared from the sensitive J-96 cell culture. Cytogenetic examinations of this cell subline showed its karyological characteristics to approach those of the sensitive J-96 culture. The modal number of chromosomes and the number of chromosomes 2, 9, 11, 12, and 21 were completely restored and marker chromosomes typical of the sensitive culture appeared.

[Restoration of the sensitivity of cells resistant to Coxsackie B3 virus after treatment with sensitive cell filtrate].

The study was done with J-96 cell line sensitive to Coxsackie B3 virus and the subline J-41 derived from it and resistant to this virus. In order to determine the substrates responsible for the susceptibility or resistance of these cells to Coxsackie B3 virus, homogenates and filtrates of the susceptible cells were inoculated into resistant ones and vice versa. Inoculation of the resistant cell homogenates into the susceptible cells at various intervals after virus inoculation did not inhibit virus development.

[Experimental myocardiopathy caused by the herpesvirus].

Mice weighing 18--20 g were inoculated with herpes simplex virus type I. The rate of pathological changes in the myocardium was found to depend on the route of virus inoculation and the time of heart examinations in the infected animals. The development of myocardiopathies was not determined by the virus dose used in the test.

[Relationship of the characteristics of the chromosome set in human cell cultures to the production and antiviral action of interferon].

The role of chromosomes 2, 5, 16, and 21 in production and effect of human interferon was checked in human diploid cells, human heteroploid cells J-96 and clone J-41 thereof. The J-41 cells were found to have a lower number of chromosomes 2 as compared to the other cells under study; J-41 cells produce less interferon than the other cells. Most J-41 cells lack chromosome 21.

[Relationship between group G chromosomes, especially chromosome 21, and the sensitivity of human cells to Coxsackie B viruses].

The R-method of differential chromosome staining by length was applied to comparative karyological studies on the culture of J 96 human cells susceptible to enteroviruses, and on the J 41 cell line derived from this culture and possessing high specific resistance to Coxsackie B viruses. Karyotype of the J 41 cell line was shown to be deprived of chromosome G21 (P less than 0.0001).

[Formation of heterosymplasts in human reticular cell cultures].

The cell fusion has been studied in human reticular cell cultures J-96 and J-41 treated with the Sendai virus or with polyethylene glycol 1000 and 6000. The J-96 cells have a high alkaline phosphatase activity, in J-41 cells the enzyme is not detectable. No heterogenous alkaline phosphatase activity was seen in the protoplasm of symplasts 18 hours after virus cell fusion.