Human spontaneous laryngeal carcinoma HEp-2 cells are chronically infected with SRV-1 virus, a variant of simian type D retrovirus.

A type D retrovirus chronically persisting in HEp-2 cells from human laryngeal carcinoma was analyzed by PCR and sequenced. This virus is most similar to SRV-1 and probably represents one of its subtypes.

[Detection of markers of the human T-cell leukemia virus in patients with T-cell lymphoma and Kaposi's sarcoma]. / Obnaruzhenie markerov virusa T-kletochnogo leikoza cheloveka u bol'nykh T-kletochnoi limfomoi i sarkomoi kaposhi.

Nine patients with Kaposi's sarcoma and five suffering from T-cell lymphoma have been examined. Antibodies to HTLV-1 were not found in these patients. The primary cellular cultures were isolated from blood and lymph nodes of the patients. Viral particles (type C) were found in the culture obtained from the patient with lymphoma of T-cell origin. DNAs from the primary cellular cultures from patients with lymphoma or sarcoma contained the sequences homologous to gag-gene of HTLV-1. The data suppose the patients with T-cell lymphoma and Kaposi's sarcoma to carry HTLV-1 virus.

[Antinuclear, anticentromere and anti-ScL-70 antibodies in rheumatic diseases]. / Antinuklearnye, antitsentromernye, anti-ScL-70 antitela pri revmaticheskikh zabolevaniiakh.

Methods are described that are used for the titration of antinuclear, anticentromere, and anti-Scl-70 antibodies in systemic scleroderma, systemic lupus erythematosus, and rheumatoid arthritis: indirect immunofluorescence with various antigenic substrates (sections of fresh-frozen rat liver and Hep-2 cell culture), counter-current immunoelectrophoresis, isolation of Scl-70 antigen. Use of Hep-2 cells as a substrate for indirect immunofluorescence was found clinically and diagnostically more effective since it permitted the detection of anticentromere antibodies and anti-Scl-70. Nucleolar, mottled, homogeneous, marginal immunofluorescence types were observed when rat liver sections and Hep-2 cells were used for substrates. Anticentromere antibodies and anti-Scl-70 were isolated significantly more frequently in systemic lupus erythematosus or rheumatoid arthritis.

[Antibodies to the structural and nonstructural gag-coded proteins of type-D retroviruses in patients with lymphadenopathy]. / Antitela k strukturnym i nestrukturnym gag-kodiruemym belkam retrovirusov tipa D u bol'nykh limfoadenopatiiami.

Screening of antibodies to structural and nonstructural gag gene-coded proteins in humans with lymphadenopathy and AIDS was performed by means of radioimmunoprecipitation (RIP) and western blotting. Pr78gag precursor of gag-coded proteins of type-D retrovirus from Hep-2 cells served as an antigen in RIP tests. Total number of sera (of humans with lymphoadenopathy) under RIP analysis was 18 and one sera of AIDS patient. Six of them reacted with Pr78gag and one out of one AIDS serum. Over 80 sera samples of humans with lymphadenopathy have been tested by means of western blotting with proteins of Mason-Pfizer monkey virus as antigens. Antibodies to p27 (major internal protein of Mason-Pfizer monkey virus) were detected in 12 sera samples of those with lymphadenopathy (dilution 1:100) and in 9 out of 12 sera of AIDS patients (dilution 1:100-1:400). Results obtained make it possible to predict that type-D retroviruses are associated with acquired immunodeficiency syndrome and generalized lymphadenopathy and could play some role in development of this illness in humans.

[Antibodies against structural proteins of carlaviruses in human and other mammals]. / Antitela k strukturnym belkam karlavirusov u cheloveka i drugikh mlekopitaiushchikh.

The study of four isolates of chrysanthemum B-virus (CVB) has shown the virus to have a single 40 Kd structural protein able to dissociate under the definite conditions forming the truncated (for 3 and 6 Kd) polypeptides having preserved their whole antigenic determinants. The human plasma is shown to contain antibodies reacting with the structural protein B-BX and, approximately 10 times weaker with the structural protein of another carlavirus, potato M-virus. Interaction of antibodies with CVB is found to take place due to F(ab)2 fragments. The analogous reaction with the proteins of other plant viruses or retroviruses has never been registered. Antibodies reacting with CVB protein are also present in the plasma of green monkey, rabbit, mouse and goat but in lesser quantities than in human plasma. Two possible explanations are proposed for the presented data, either immunization of mammalians by the protein or peptide containing its antigenic determinant, or the accidental coincidence of CVB antigenic determinant with some viral, bacterial or fungal determinant widespread in mammalians.

[Antibodies to the structural proteins of the chrysanthemum B-virus in normal human plasma]. / Antitela k strukturnym belkam B-virusa khrizantemy v normal'noi plazme cheloveka.

Electrophoretic analysis of the protein composition of chrysanthemum B virus (ChrBV), a member of the carlavirus family, performed in 7.5-15% gradient polyacrylamide gel with 0.1% SDS revealed the presence in the preparation of two proteins with molecular weights of 34,000 and 37,000. The densitometric treatment showed their ratio approximating 2:1. Antibodies to these proteins were detected in a pool of normal human plasma and in individual human sera by the immune blotting test. No antibodies to ChrBV proteins were found in goat and rabbit sera. Normal human plasma contained no antibodies to structural proteins of tobacco mosaic, cucumber mosaic, and rock-cress mosaic viruses. It is presumed that the presence of antibody to ChrBV proteins may be associated either with casual structural relationship of viral and some cellular (serum) proteins or with immunization of man with ChrBV or immunologically related carlavirus(es).

[Advantages and disadvantages of silver staining of proteins in polyacrylamide gel]. / Dostoinstva i nedostatki metoda okraski serebrom belkov v poliakrilamidnom gele.

Sensitivity of protein staining with Serva blue G-250 (Coomassie brilliant blue G-250 analogue) in polyacrylamide gel was determined. It has been shown that protein staining with 0.1% Serva blue G-250 results in the recovery of 80 to 35 ng of single protein, that is almost 10 times higher than reported previously for Coomassie brill. blue G-250 (or R-250) staining. The comparison of the sensitivity of Serva blue G-250 protein staining in PAAG and AgNO3 has shown that AgNO3 staining was approximately 18-30 (but not 100 times, as it had been thought before) times more effective for the majority of proteins under study. Silver staining of some proteins, for instance ribonuclease and a number of retrovirus-specific structural proteins, was of lower efficacy. Thus, to obtain reliable results protein electrophoresis in PAAG should be followed by both staining procedures.

[Nonstructural glycosylated polyproteins coded for by the gag gene of retrovirus type D expressed on the plasma membrane]. / Nestrukturnye glikozilirovannye poliproteiny, kodiruemye genom gag retrovirusa tipa D, ékspressirovany na plazmaticheskoi membrane.

Studies of virus-specific proteins of type D retroviruses by radioimmunoprecipitation (RIP) using various radioactive precursors demonstrated in HEp-2 cells producing these retroviruses the presence of two glycosylated gag-coded polyproteins with molecular weights of 78 K and 90 K. The same polyproteins were found by lactoperoxidase iodination and RIP on the plasma membrane of the cells. Comparative studies of these glycoproteins by the limited proteolysis method showed the sites for trypsin action in them to be located in similar places of protein bases which indicated their structural relationship. It is suggested that glycosylated gag-coded polyproteins of retroviruses (including type D retroviruses) play the role of receptors for certain mitogens the seizure of which stimulates cell proliferation.

[High-resolution electrophoresis in a new polyacrylamide-gel block]. / Vysokorazreshaiushchii élektroforez v novom bloke poliakrilamidnogo gelia.

A new gel block for electrophoretic separation is offered. When viewed frontally, the block has a form of a trapezium. During electrophoresis a gradient of voltage is formed in such a block, as a result of which the mobility of macromolecules to be separated markedly decreases. The combination of the block with polyacrylamide gel gradient makes it possible to raise the resolving power of electrophoresis up to 300-400 dalton. The new gel block can be applied successfully to the performance of fine biochemical assays and molecular-biological studies of proteins, glycoproteins and nucleic acids.

[Processing of proteins coded by the gag gene of retrovirus type D from HEp-2 cells]. / Protsessing belkov, kodiruemykh genom gag retrovirusa tipa D iz kletok HEp-2.

The early products of translation of the gag gene of retrovirus type D from HEP-2 cells were studied. The radioimmunoprecipitation test in the pulse-chase modification showed the proteins, products of the gag gene translation of this retrovirus, to be formed from polyprotein with a molecular weight of 78000. The use of serine proteinases inhibitors revealed 2 additional polyproteins with molecular weights of 37000 and 33000. The authors suggest a probable scheme of Pr78 processing which includes an initial cleavage of this polyprotein in two parts (37000 and 33000, respectively) followed by formation of viral structural proteins from these parts upon further cleavage.

[Further study of spontaneous virus production using transplantable HEp-2 cells as a model]. / Dal'neishee izuchenie spontannoi virusnoi produktsii na modeli perevivaemykh kletok HEp-2.

Two maxima of optic density were observed at zones of gravity 1.27 g/ml and 1.15-1.16 g/ml by sedimentation equilibrium in sucrose gradient of cultural fluid, obtained from the transplantable cells of the HEP-2 strain and concentrated by ultracentrifugation. These fractions thus isolated were tested for presence of RNA- and DNA-dependent DNA-polymerase. The structures with the density of 1.15-1.16 g/ml were identified with the oncornaviruses on the basis of characteristics flotating density, presence of RNA-dependent DNA-polymerase. Analyses of products of RNA- and DNA-dependent polymerases reaction, flotating density of oncornaviral nucleotides in sucrose and CsCl gradients are presented. The optimal conditions for reverse-transcriptase reaction of virions of D type viruses are characterized.

[Detection of oncornavirus type D in continuous breast cancer cells]. / Ubnaruzhenie onkornavirusa tipa D v perevivaemykh kletkakh raka grudnoi zhelezy.

An oncornavirus immunologically similar to oncornaviruses type D previously isolated from human continuous cells was detected in continuous cells of mammary cancer (SH3). The culture produces structures having densities of 1.18--1.19 and 1.22 g/ml which contain high molecular RNA (68S) and reverse-transcriptase activity. The similarity of this virus with other oncornaviruses was also demonstrated in molecular hybridization experiments.

[Differentiation of type D virus from continuous human cells (Il'in-Bykovskii virus) and Mason-Pfizer monkey virus by the antigens of the viral envelopes]. / Differentsiatsiia virusa tipa D iz perevivaemykh kletok cheloveka (virusa Il'ina-Bykovskogo) i obez'ian'ego virusa Mezon-Pfaizera po antigenam virusnykh obolochek.

For differentiation of Ilvin-Bykovsky virus (IBV) and monkey Meson-Pfeizer virus (M-PMV) the method of virus neutralization with antibodies against the envelope virus antigen was used. The viruses were cultivated in similar human embryo cells. The results of the virus neutralization were determined by presence or absence of the gs-antigen in the infected cells. The antiserum to M-PMV envelope antigens did not neutralize the IBV antigen. It has been concluded that IBV and M-PMV differ by their envelope antigens and should be regarded as different viruses.