[The LMP1 oncogene sequence variations in patients with oral tumours associated or not associated with the Epstein Barr].

The role of the Epstein-Barr virus (EBV), a ubiquitous lymphotropic human herpesvirus type 4, in the etiology of nasopharyngeal carcinoma (NPC) is not fully understood. The mechanism of NPC carcinogenesis, associated with the virus, is also not clear. The objective of present investigation was to carry out comparative analysis of the structure of an LMP1 oncogene of EBV in viral isolates obtained from patients with two types of tumors of the oral cavity: (a) associated (i.e., NPC) and (b) not associated (other tumors of the same anatomical region, OTOC) with EBV. Comparative analysis of C-terminal regions of LMP1 variants that was based on a sequence analysis of LMP1 from tumor, blood and throat washing samples of NPC and OTOC patients showed that all structural characteristics of LMP1 in both groups of patients were genetically similar, and differences found between compared parameters were statistically insignificant. Thus, for the first time it has been revealed that in NPC and OTOC patients in Russia genetically related EBV strains with structurally similar LMP1 variants are persisting that are likely to reflect a polymorphism of the virus circulating in population. The findings allow us to suggest that in non-NPC-endemic regions of the world, which include Russia, the risk of NPC development does not depend on the EBVstrain and its variant of LMP1 so much, but mostly from the genetic predisposition of infected persons to the disease and the exposure to other, as yet unknown agents.

[LMP1 gene polymorphism in patients with Epstein-Barr virus-negative gastric carcinomas in Russia].

The investigation was undertaken to study the molecular characteristics of Epstein-Barr virus (EBV) LMP1 gene samples amplified from the tumor and intact tissues of patients with EBV-negative forms of gastric carcinoma (GC). The genetic structure of these samples determined by their sequencing was compared with that of the gene samples isolated from the cells of oropharyngeal washing specimens from the same patients with GC, as well as peripheral blood lymphocytes of patients with infectious mononucleosis (IM) and blood donors. The findings suggest that the samples of tumor tissue LMP1 from patients with GC have higher divergence than those from patients with IM and blood donors although no specific variants of the gene for GC were found. Comparison of LMP1 sequences from tumor tissue and cells of oropharyngeal washing specimens from the same patients with EBV-negative GC revealed the common LMP1 variant in 2 cases while they differed in 3 cases. The findings are an initial step in studying the role of EBV in the carcinogenesis of EBV-negative GC that is likely to be established by investigations on representative clinical material, by applying the up-to-date technologies.

[Mutations of the Epstein-Barr virus LMP1 gene mutations in Russian patients with lymphoid pathology and healthy individuals].

Epstein-Barr virus (EBV) is an etiological agent of a number of benign and malignant human diseases, such as infectious mononucleosis (IM), Hodgkin's lymphoma (HL), and non-Hodgkin's lymphoma (NHL). EBV latent membrane protein 1 (LMP1) gene (recognized as a viral oncoprotein) of various clinical and geographical origin was found to have different types of amino acid mutations affecting its biological activity. Since there was no information on the strain differences in LMP1 of EBV persisting in Russia, the authors made a sequence analysis of LMP1 samples amplified from the biological materials of Russian patients with IM, HL, and NHL and healthy individuals. The studies have shown that LMP1 variants of Russian origin are a mixed heterogeneous group containing both the earlier characterized and presumably new genetic variants. Among the point amino avid substitutions, the mutations S366T, F106Y, 185L, and E328Q associated with the enhanced transforming activity of a LMP1 molecule and its reduced cytotoxicity. There was no specific association between the certain Russian variants of LMP1 and the specific forms of the disease (IM, HL, and NHL).

[The distribution of HLA genes in Russian patients with germ cell tumors].

The correlation between DRB1, DQA1, and DQB1 genes of HLA class II, and the development of germ cell tumors (GCTs), as well as serological response to HERV-K proteins were investigated. Genomic DNA prepared from 99 GST patients was subjected to HLA typing by polymerase chain reaction (PCR) using the set of sequence specific primers (PCR-SSP). This set of primers made it possible to detect 14 specificities of DRB 1 locus, 12 alleles and groups of alleles of DQB 1 locus, and 8 alleles of DQA1 locus. Alongside with the definition of the occurrence of HLA markers in the total group of patients, the frequency of the occurrence of HLA-DR-DQ alleles was calculated in: 1) patients with different morphological forms of GSTs (seminomas and non-seminomas); 2) GCT patients producing or non-producing antibodies to Gag and/or Env HERV-K proteins. The comparison group consisted of 300 Moscow blood donors. The study did not reveal statistically significant differences in the frequency of the occurrence of DRB1, DQA1, and DQB1 alleles between the total group of GCT patients, its subgroup, and the control group. Thus, the data obtained demonstrated the absence of a strict correlation between the distribution of HLA class II alleles and GCT occurrence in the Russian population, as well as the ability of GCT patients to develop an antibody to HERV-K proteins, though more numerous observations are required to confirm this conclusion.

[LMP1 gene variants of Epstein-Barr virus in patients with some lymphoproliferative malignancies].

The samples of tumor biopsy, blood, and saliva from 10 patients with Hodgkin's disease, 10 patients with non-Hodgkin's lymphoma, and the blood samples of 20 donors were tested by polymerase chain reaction (PCR) for standard (wild) B95-8 and Cao-like (deleted) variants of the LMP1 gene. The paraffin sections of most PCR-tested tumors were also investigated by immunohistochemistry using the monoclonal antibodies S12 or 7D7 to detect the expression of the standard or Cao-like variants of LMP1 protein, respectively. It is suggested that Eptein-Barr virus (EBV) that contains the above deletion is not crucial for the development of the study lymphoproliferative malignancies. The fact that in some cases there is the Cao-like variant of LMP1 in the tumor biopsy specimen and its standard variant LMP1-B95-8 in the biological fluids of the same patient is very likely to suggest that the patient is infected with both types of the virus or there is genetic mutation(s) of EBV during viral carcinogenesis preceding or accompanying the development of a tumor.

[Search for HHV-8 associated diseases reservoir and spread paths of HHV-8 in Russia]. / Poiski HHV-8-assotsiirovannykh zabolevanii, rezervuara i putei rasprostraneniia HHV-8 v Rossii.

Summarized in the paper are study results of human herpesvirus type 8 (HHV-8) and of its association with Kaposi's sarcoma (KS). The data obtained denotes that the share of individuals producing the antibodies to HHV-8 in a majority of studied patients was low and ranged form 0 to 5.5%, which is indicative of a low degree of the virus spread in population. At the same time, a high share of persons with antibodies to HHV-8 was detected among HIV-infected homosexuals (71.4%), kidney recipients (26.0%) and among AIDS-KS patients (78.6%). It was also unexpectedly high among patients with T- and B-cell lymphomas (50%), encephalopathy (27.3%) and with stomach cancer (41.8%): the appropriate parameters were 7-12-fold higher versus healthy subjects. The HHV-8 markers, i.e. virus specific antibodies and/or nucleotide sequences of the virus, were detected in blood serum and ejaculate of a significant number of patients with different pathologies of the prostate. Such detection of viral markers in the above categories of patients is suggestive of that sexual contacts with such patients are decisive for the HHV-8 spread in population.

[Antibodies to herpesvirus type 8 in Kaposi's sarcoma patients and controls in Russia]. / Antitela k gerpesvirusu tipa 8 u bol'nykh sarkomoi Kaposhi i lits kontrol'nykh grupp v Rossii.

The purpose of the present study was to investigate the HH-8 seroprevalence among patients with Kaposi's sarcoma (KS), melanoma and gastric carcinoma (GC) as well as among renal recipients and blood donors. The obtained data revealed a high percentage of seropositive KS patients, which ranged from 83.6% in the classical disease type to 68.8% and to 71.4% in the immunosuppressive and AIDS-associated disease types, respectively. On the whole, the positive humoral response to HHV-8 reliably correlated with the positive findings if the viral genetic information in tumor tissue samplings. An unexpectedly high percentage of seropositive persons was found among the GC patients (41.8%) and among the renal recipients (26%), which is apparently predetermined by the immunosuppressive condition of such patients. Seroprevalence was found only in 4% of blood donors. Thus, the obtained data make it possible to conclude that KS cases, as diagnosed in Russia, are tensely associated with HHV-8 in spite of a low virus spread among the healthy population. Patients with pathology concomitant with a pronounced immunosuppression are characterized by a high prevalence of HHV-8 and belong to the category of persons with a KS risk.

[Molecular biological and clinical-morphological studies of gastric tumors associated with Epstein-Barr virus]. / Molekuliarno-biologicheskoe i kliniko-morfologicheskoe issledovaniia opukholei zheludka, assotsiirovannykh s virusom Epshteina-Barr.

The paper presents the results of the studies of gastric cancer (GC) associated with Epstein-Barr virus (EBV) among the patients residing in 4 geographical regions. In situ hybridization (ISH) techniques revealed that 49(11.4%) of the 430 examinees were EBV positive (EBV+), the virus-specific marker mRNA-1 of EBV, EBER-1) was found to be present in 80-100) of tumor cells. The proportion of EBV(+)-associated GC cases in different geographic regions ranged from 7.3 to 15%. These tumors were predominant in males (15%) as opposite to females (5.5%). Histological types most common among EBV+ tumors and their location in the stomach are also described. Serological findings indicated that the increased anti-EDV antibody response in 70% of GC cases coincided with the presence of the viral genetic information detected by ISH. In contrast to a humoral response to EBV, a humoral response to Helicobacter pylori was equal both in patients with EBV(+)- and EBV(-)-associated gastric tumors. Further molecular biological analysis of EBV isolates from virus positive and virus negative GC may answer the question whether there are really the so-called tumor and non-tumor variants of EBV.

[Detection and characterization of gastric carcinoma associated with epstein-barr herpes virus]. / Obnaruzhenie i kharakteristika opukholei zheludka, assotsiirovannykh s virusom gerpesa épstein-barr.

The present investigation was carried out to estimate the incidence of Epstein-Barr virus (EBV)-associated cases among gastric carcinoma (GC) patients in Russia. Carcinoma specimens from 184 patients with GC treated at the Cancer Research Center were investigated by EBV encoded RNA-1 (EBER-1) in situ hybridization. Seventeen (9.24%) cases showed uniform EBER-1 expression restricted to the carcinoma cells. Hybridized signals were not detected in the non-neoplastic gastric epithelium. EBV involvement was significantly more frequent among males, especially in the tumors belonging to less differentiated types (moderately differentiated tubular adenocarcinomas and poorly differentiated solid adenocarcinomas) and located in the upper stomach (cardia and middle part). Most EBV-positive GCs were characterized by great lymphoid compartment involvement. The findings of the distribution of EBV-positive. GCs by sex, site, and histology are similar to those in Japan; however, the detection rate of EBV-positive cases in Russia is higher than that in Japan (6.7%) and lower than that in the USA (16%).

[Features of adult T-cell leukemia virus reproduction in B-cell lines and it's interaction with the Epstein-Barr herpesvirus]. / Osobennosti reproduktsii virusa T-kletochnogo leikoza vzroslykh v B-kletochnykh liniiakh i ego vzaimodeistviia s gerpesvirusom Epshteina-Barr.

Interaction between human T-cell leukemia virus (HTLV) with B cells and Epstein-Barr virus (EBV) was studied by immunoblotting, immunofluorescence, virus isolation in permissive T-cell cultures, and polymerase chain reaction (PCR). HTLV-1 in vitro infects the B-cell cultures containing EBV but not EBV-negative cell lines. Productive infection of EBV+ B cells was associated with syncytium formation which led to the elimination of HTLV-1 producing cells. However, the remaining B-cell population contained gag, pol, and pX--the "silent" provirus sequences. HTLV-1 infection of B cells altered the expression of some latent proteins of EBV (EBNA-1, EBNA-2, EBNA-5, and LMP). The changes were represented by increase of molecular weight and/or appearance of additional proteins and were individual for each cell line. Alteration of EBV protein expression may change the functional activity of these proteins, but this hypothesis is to be tested.

[Variants of the interaction of the human T-cell leukemia virus (HTLV-I) with the B-cells of lymphoblastoid lines]. / Varianty vzaimodeistviia virusa T-kletochnogo leikoza cheloveka (HTLV-I) s B-kletkami limfoblastoidnykh linii.

B-cell lymphoblastoid lines which are known to be derived by in vitro inoculation of B-lymphocytes with Epstein-Barr herpes virus (EBV) were shown to be infected with HTLV-1. Three possible variants of HTLV-1 interaction with cells were demonstrated by immunoblot, polymerase chain reaction, and virus isolation: (1) prolonged productive infection; (2) infection of the cells manifested only by the presence of "silent" virus sequences; (3) temporary production of HTLV-1 (3.5 months) after the end of which genetic material persisted in the cells. The long-term productive HTLV-1 infection in EBV-infected B-cells was found to influence the functioning of EBV genome which was manifested by expression of two additional proteins of EBNA-5 group and by changes in the intensity and pattern of LMP and EBNA-2 proteins the functioning of which is associated with immortalizing and transforming properties of EBV.

[A study of sera positive and doubtful for antibodies to the human immunodeficiency virus for the presence of HTLV-I-specific antibodies]. / Issledovanie syvorotok, polozhitel'nykh i somnitel'nykh k virus immunodefitsita cheloveka, na nalichie HTLV-I-spetsificheskikh antitel.

The results of examinations for the presence of antibody to HTLV-I of 205 sera which were positive or indefinite (doubtful) with regard to HIV are presented. No evidence indicating simultaneous infection with HIV and HTLV-I viruses in 18 HIV-positive subjects was obtained. Antibodies to gag-proteins p19 and p28 HTLV-I were detected in one serum showing primary reactivity in screening for HIV antibodies. Problems of HIV and HTLV-I occurrence and sensitivity of screening test systems are discussed.

[Screening of sera from the adult populations of some USSR regions for antibodies to the human T-cell leukemia virus type I (HTLV-I)]. / Skrining syvorotok vzroslogo naseleniia nekotorykh regionov SSSR na antitela k virusu T-kletochnogo leikoza cheloveka I tipa (HTLV-I).

The results of serologic survey of 4118 residents of the USSR Far East from 16 to 82 years of age and 1037 blood donors for antibody to HTLV-I by the method of passive agglutination of gelatin particles coated with viral proteins are summarized. The portion of HTLV-1 seropositive subjects in the Khabarovsk Territory was 1.79% (25 out of 1391), in the Maritime Territory 2.2% (18 out of 801), in the Sakhalin Island 1.6% (26 out of 1557), and in Kamchatka 1.6% (6 out of 369). A discrete area of a higher number of positive cases was found among Nivkhi national group in the village of Nogliki in the Sakhalin Island: 6.4% (10 out of 155). In women, antibody to HTLV-1 was found twice as frequently as in men. Seropositives to HTLV-1 among blood donors in Moscow, the town of Komsomol'sk-na-Amure, and the town of Yuzhno-Sakhalinsk comprised 1.4%, 1.6%, and 5.45%, respectively. The occurrence of HTLV-1 infection among the normal population of the Far East and especially among blood donors attests to the expedience of wider seroepidemiological surveys of the population and especially donors for HTLV-I infection in other regions of the USSR as well.

[A mixed infection of lymphoid cell lines by the human T-lymphotropic retrovirus type I (HTLV-I) and the measles vaccine virus]. / Smeshannaia infektsiia limfoidnykh kletochnykh linii T-limfotropnym retrovirusom cheloveka I tipa (HTLV-I) i vaktsinnym virusom kori.

Interaction of HTLV-1 and vaccine strain of measles virus (VM-L16) in different T and B cell lines was studied. VM-L16 replicated in T and B cells with a cytopathic effect. At a multiplicity of infection of 1 TCD50 per 10 cells, all the cells in cultures died within 4-13 days. No effect of HTLV-1 on cell sensitivity to VM-L16 was demonstrated. HTLV-1 produced in various T-cell lines had different syncytium-forming activity in XC cell cultures. Cocultivation of C91/pL cells with XC cells led to the formation of multiple syncytia. HUT-102 cells had no such activity. Infection of these cell lines with VM-L16 did not change their properties. Another HTLV-1-infected cell line, MT-2, caused insignificant aggregation of XC cells. Infection of the latter with VM-L16 increased the number of racemations 8-fold, and they consisted of numerous adhesive cells. The cell adhesion, however, which is the first stage of syncytium formation did nor terminate in cytoplasm confluence. MT-2 nad XC cell lines may be used as model systems for the study of various factors influencing HTLV-1 activation.

[Detection of HTLV-I viral antibodies in donor blood samples]. / Obnaruzhenie antitel k virusu HTLV-I v obraztsakh donorskoi krovi.

Sera from 867 donors were tested for antibodies to the virus of T-lymphocyte leukemia of adults (HTLV-I) in parallel by indirect immunofluorescence on acetone-fixed cells of HUT-102 culture producing HTLV-I and by agglutination test using a commercial set ("Serodia-ATLA", Japan). Twelve (1.38%) out of 867 sera were positive in the agglutination test and only 7 of them in immunofluorescence test. The specificity of the results was verified by absorption experiments. The activity of the sera in the agglutination test disappeared completely after their absorption with HUT-102 culture cells but did not change after absorption with LLU cells producing no HTLV-I despite a low percent of virus infection, donor blood control for HTLV-I infection becomes mandatory.

[Effect of a mixed viral infection on the development of neoplasms induced by oncogenic viruses]. / Vliianie smeshannoi virusnoi infektsii na razvitie neoplazii, indutsirovannykh onkogennymi virusami.

Data are presented concerning the stimulating effect of vaccinia and herpes simplex type 2 viruses on the development of leukemia in BALB/C, C57BL/6, and AKR mice. Mixed infection with PAB-49 and Marek disease virus of brown leghorn chickens was shown to increase the frequency of lymphomas development.