Epstein-Barr virus encoded BALF1 gene is transcribed in Burkitt's lymphoma cell lines and in nasopharyngeal carcinoma's biopsies.

BACKGROUND: The Epstein-Barr virus (EBV) encodes two anti-apoptotic cellular Bcl2 homologs, BALF1 and BHRF1. BHRF1 has an anti-apoptotic activity but is rarely expressed in nasopharyngeal carcinoma (NPC). However, BALF1 is not yet well characterized. OBJECTIVES: The objective of the study was to characterize BALF1 gene. First, the search of its transcriptional expression in EBV-positive B cell lines, EBV-positive Burkitt's lymphoma's cell lines and nasopharyngeal carcinoma's biopsies. Second, the examination of its anti-apoptotic activity in serum dependent assays. STUDY DESIGN: We first analysed the transcriptional expression of BALF1 by reverse transcriptase DNA polymerase chain reaction (RT-PCR) method. For the analysis of its anti-apoptotic activity, we transfected NIH3T3 cells with pBABE-BALF1 expression plasmid and studied serum dependence of these transfectants. RESULTS: BALF1 expression was detected in the latent stage and increased more significantly during the lytic phase in IgG-treated AKATA and TPA-SB-treated P3HR1-TK negative cell lines. As its expression was not affected by the inhibitor of viral DNA synthesis, this gene does not belong to late gene family. When analysed its transcription in Burkitt's lymphoma (BL)-derived cell lines and NPC biopsies, all BL-derived cell lines and more than 80% of NPC biopsies transcribed this gene. The study of serum dependence of BALF1-transfected NIH3T3 cells showed: with 10% of serum, BALF1 transfectants grew significantly more higher cell density than vector alone transfected NIH3T3 cell lines and with 1% of serum, BALF1 transfectants were capable of growing, but with about 40% reduced rate in comparison with those with 10% serum, while vector alone transfected NIH3T3 cells could not almost grow. CONCLUSION: BALF1 gene was transcribed in EBV-associated tumor cells. BALF1 could render cells to serum independent. These results suggest that BALF1 gene could play its role in EBV oncogenesis.

Expression of BARF1 gene encoded by Epstein-Barr virus in nasopharyngeal carcinoma biopsies.

We reported previously that the EBV BARF1 open reading frame encodes a Mr 31,000-33,000 protein (p31) with potential transforming and oncogenic properties. This gene was found capable of transforming both: (a) the rodent fibroblast lines Balbc/3T3 and NIH3T3 into cells producing aggressive tumors in newborn rats; and (b) the human EBV-negative B-cell line Louckes into cells leading to small tumors, which disappeared 3 weeks after injection. Our recent study showed that BARF1 ORF expression may confer the property of immortalization to primary kidney epithelial cells (M. X. Wei et al., Oncogene, 14: 3073-3081, 1997). Because this suggested that BARF1 could be involved in epithelial malignancy, we investigated its transcriptional and translational expressions in Algerian nasopharyngeal carcinoma (NPC) biopsies by reverse transcription-PCR and immunoblotting using rabbit polyclonal antisera prepared against two synthetic peptides corresponding to distinct, predicted epitopes of the BARF1 protein (NGGVMKEKD, amino acids 172-180, and GKNDKEE, amino acids 203-209). The BARF1 ORF was found to be transcribed and translated in >85% of our NPC biopsies, with high p31 protein level detected in several NPC patient biopsies as well as in NPC-derived xenografts. Our observation of BARF1 expression in a large proportion of NPC epithelial cells suggests that this EBV gene might play an important role in the malignant transformation of human epithelial cells in vivo.

Different distribution of H1-H2 Epstein-Barr virus variant in oropharyngeal virus and in biopsies of Hodgkin's disease and in nasopharyngeal carcinoma from Algeria.

In a previous study of Epstein-Barr virus (EBV) strains in North African nasopharyngeal carcinoma (N PC) biopsies, we have found that the viral strain present was of A/F/W'-I'/Xhol kept/H1-H2 type, while the strain associated with Chinese NPC was the A/"f"/W'I'/Xhol lost/H type. Using the restriction fragment length polymorphism (RFLP) and PCR-RFLP methods, the present study analyzed the H1-H2 variant in different clinical samples from Algeria, including the saliva of healthy EBV-positive individuals and patients with NPC or Hodgkin's disease (HD), as well as HD biopsies and lymphoblastoid cell lines (LCLs) established from the oropharyngeal virus-infected cells. Our results demonstrate that, in contrast to the H1-H2 variant found in NPC biopsies, the H genotype was dominant in HD biopsies. Moreover, H genotype was also dominant in the oropharynx of healthy EBV-positive individuals, of patients with NPC and with HD. Our results clearly indicate that in North Africa the EBV strain present of NPC biopsies is different from that shed in the oropharynx. This may suggest a specific distribution of the H1-H2 variant in the NPC epithelial tumor, whereas the H genotype is dominant in HD biopsies and in the oropharynx. The specific association of both viral strains with these 2 distinct diseases in North Africa may reflect a difference in tumorigenicity.

[Immunocapture-hemagglutination technique]. / La technique d'immunocapture hémagglutination.

Virus specific IgM antibodies are very useful for the diagnosis of primer infection by the rubella and parotidis viruses. ELISA is the method usually used to detect IgM antibodies. The reactives and in some laboratories the apparatus are not always available. We carried out a serological method based on the immunocapture inhibition of hemagglutination of theses viruses by positive sera. 39 sera and 80 sera collected from patients and healthy population have been respectively studied to detect antirubella and antiparotidis IgM. The test appeared as sensitive and specific as the immunocapture IgM ELISA.

[Introduction to a study of specific antibodies (IgG and IgM) detection with ELISA in the diagnosis of poliomyelitis]. / Introduction à une étude sur la détection des anticorps spécifiques (IgG et IgM) par ELISA dans le diagnostic de la poliomyélite.

Samples of single sera collected from 38 patients with different clinical diagnosis were studied in order to perform ELISA techniques with the purpose of detecting poliomyelitis IgG and IgM antibodies. The résults were compared through antibody titration by neutralization test. 21 pairs of sera from infants suffering from acute flaccid paralysis were studied by ELISA-IgM, ELISA-IgG and neutralization test. Stool samples were collected from 20 of the latter patient. Wild poliovirus type 1 was isolated in 8 cases. ELISA-IgM technique was positive in 14 cases. The true positive poliomyelitis diagnosis was based on the persistence of flaccid paralysis 60 days after the onset and on wild poliovirus isolation with significant increase in antibody level. 16 cases were classified as poliomyelitis, 2 cases as non poliomyelitic paralysis and 3 cases as undetermined. 16 out of the 18 well established diagnosis were in agreement (88.8%) with the detection or not of IgM antibodies by ELISA. The specificity of these IgM ELISA antibodies was examined by studying 11 cases of lymphocytic meningitis. Cross reaction in serological responses between polioviruses and coxsackieviruses was observed. These cross reactions should be evaluated by studying a greater number of cases. The poliovirus ELISA-IgM is a sensitive, economical and rapid method to be used in poliomyelitis diagnosis to complete the neutralizing test and virus isolation.

Transcriptional expression of Epstein-Barr virus genes and proto-oncogenes in north African nasopharyngeal carcinoma.

Cases of nasopharyngeal carcinoma (NPC) from North Africa show an unusual bimodal age distribution. As elsewhere, the tumor is closely associated with the presence of Epstein-Barr virus (EBV). The expression of EBV genes and c-onc genes was studied in biopsy specimens from tumors at different clinical stages from 11 young (10 to 30-year-old) and 11 adult (30 to 65-year-old) patients. It was found that the two age groups do not differ in their pattern of gene expression, that there is a tendency for later stage biopsies to express more viral and c-onc transcripts, and that samples expressing larger numbers of EBV genes also tend to express many different c-onc specificities.

Purified recombinant EBV desoxyribonuclease in serological diagnosis of nasopharyngeal carcinoma.

To evaluate applications of highly purified recombinant EBV DNAase in the diagnosis and prognosis of NPC, we tested sera from patients with NPC, other EBV-associated diseases and EBV-seropositive and -seronegative healthy subjects by immunoblotting and DNAase inhibitory assay. The results were compared with those obtained by the conventional immunofluorescence assays against the EBV-specified early antigens and capsid antigens. The antigenic specificity of the immunoblotting assay for IgG antibody against the viral enzyme, but not that for the IgA antibody, was correlated with DNAase-inhibitory activity of the sera and their titers of IgG antibodies against the viral early antigens. Purified IgA as well as IgG from NPC sera inhibited enzyme activity with similar efficiency. The use of highly purified viral DNase has increased the sensitivity of detection of the corresponding antibodies by immunoblotting, with the IgG antibody being detected in all but one, and IgA antibody in all but 2, of the 174 NPC sera tested. The IgG antibody was also commonly detected in the other groups of control sera, while the IgA antibody was detected in about 10% of African Burkitt's lymphoma and Algerian Hodgkin's lymphoma patients and less than 3% of the other control subjects. These results suggest that IgA antibody against recombinant EBV DNAase may be useful in the diagnosis of NPC, but the level of this antibody did not appear to be related to clinical stages of this cancer.

Epstein-Barr virus genotypes in NPC biopsies from north Africa.

The genotypes of Epstein-Barr virus (EBV) were investigated in North African nasopharyngeal carcinoma (NPC) biopsies, nasopharyngeal chronic inflammation (NCI) biopsies, and saliva of healthy individuals from Algeria and Tunisia where there is an intermediate incidence of NPC. The prevalence of A-type virus in NPC, NCI biopsies and saliva of healthy individuals was found in these regions by means of a PCR assay. Restriction enzyme polymorphism analysis by Southern blotting revealed that all North African EBV variants have a conserved restriction site on BamHI W'-I' and XhoI LMP gene. No additional BamHI enzyme site on the BamHI-F fragment was observed; however, the presence of an extra BamHI site on the BamHI-H fragment giving 2 HI and H2 fragment-like EBV M-ABA strains was found. All EBV strains present in NPC or NCI biopsies at all ages were homogeneous in these polymorphisms and no correlation was observed between the EBV genotypes from NPC patients and clinical stages of the cancer. These characteristics revealed a significant difference between the EBV variants common in Chinese NPC and those in North African NPC.

Co-existence of the A and B types of Epstein-Barr virus DNA in lymph node biopsies from Algerian patients with Hodgkin's disease and non-Hodgkin's lymphoma.

The association of Epstein-Barr virus (EBV) with Hodgkin's disease (HD) and non-Hodgkin's lymphoma (NHL) was examined in Algerian patients. The DNA extracted from fresh lymph node biopsies of 17 HD and five NHL was analysed by polymerase chain reaction (PCR). Fifteen out of 17 biopsies (88%) from HD contained EBV genome. Viral type analysis showed the coexistence of A and B types of EBV in 14 biopsies (93%), and the sole presence of A type virus in one biopsy. Among five NHL biopsies examined, four biopsies contained both A and B types of EBV, while one revealed A type-virus only. This co-infection of Algerian HD and NHL patients does not seem to be related with any histologic form of these diseases. The analysis of viral types in the saliva from 12 Algerian healthy individuals revealed six EBV positives with only one A type. Two types of lymphoma in Algeria therefore are closely associated with EBV, and are characterized by coinfection with A and B types of EBV.

[Detection of human papillomavirus (H.P.V.) DNA in genital lesions using molecular hybridization]. / Détection du DNA des virus du papillomme humain (H.P.V.) dans les lésions génitales par hybridation moléculaire.

Detection of human papilloma virus in genitals lesions by molecular hybridization. Some H.P.V. types are sexually transmitted and infect genital organs. We have used molecular hybridization to examine the distribution of H.P.V. 6 or II and H.P.V. 16 in benign, premalignant and malignant genital lesions from 344 patients. The frequency of H.P.V. 16 positive cases increases as the cervical lesions progress to malignancy: 57/78 are positive (73%) in the carcinomas, 29/83 are positive (35%) in mild or moderate dysplasia. The majority of benign condylomata acuminata harbors DNA of other types, namely H.P.V. 6 and II.

Chlamydial genital infection in Algiers: a sero-epidemiological survey.

Using a microimmunofluorescence test, the prevalence of antichlamydial immunoglobulin (Ig) G in 720 people in Algiers was studied. 34 (36%) of women with low genital infection, 28 (30%) of 91 patients attending a cancer screening clinic, and 44 (100%) of prostitutes had antichlamydial IgG at a titre greater than or equal to 1:16. Among 180 women seeking a rubeola test, 48 (26.6%) had IgG titres greater than or equal to 1:16. 144 infants less than 3 months old were also tested and 16.6% of them had IgG titres greater than or equal to 1:160; 20 (20.7%) of 97 men with chronic urethritis had IgG titres greater than or equal to 1:16. Antibody titres suggesting active disease in prostitutes, patients attending the cancer screening clinic and women with low genital infection were found in 95%, 11% and 17% respectively.

[Acute respiratory infections of viral origin in the children of Algiers, Algeria based on a seroepidemiological study]. / Les infections respiratoires aiguës d'origine virale chez les enfants à Alger--Algérie, à travers une étude séro-épidémiologique.

401 double serum samples from 0 to 14 year old children with acute respiratory diseases (ARD) were analysed in view to establish the viral etiology. 198 (49.4%) out of the 401 were positive. The syncytial respiratory virus (SRV) was the most frequent (29.8%) among the positives, followed by the parainfluenzae virus type 3 (24.7), the influenza A virus (23.7%), the parainfluenzae type 1 (8.5%), the influenza B (7%) and the parainfluenza type 2 (2%). Seven samples out of 109 were positive for adenovirus. The SRV infections were very frequent before one year of age and after six. The parainfluenza virus type 3 was found mostly during the second year of life and was different in this from the types 1 and 2 prevalent after the age of six. The SRV is responsible for subglottic ARD (73%), as well as the parainfluenza virus type 3 (68.5%), the influenza virus types A (69%) and B (61.5%). On the contrary, the parainfluenza viruses types 1 (70%) and 2 (67%) attacked especially the upper respiratory tract. Studies were also worked out on the effects of season, sex, antibiotherapy, as well as on the viruses most incriminated in hospitalization.

[Genital Chlamydia infections. A seroepidemiologic study in Algiers]. / Les infections génitales a Chlamydia. Etude séroépidémiologique a Alger.

The prevalence of anti-Chlamydia antibodies was studied among 329 patients divided into 5 groups, 34 (36%) of the women with a low genital infection have antibodies at a titre greater than 16 versus 12 (17%) of the patients attending the women's clinic for routine pelvic examination. 44 (100%) of 44 prostitutes had antibodies greater than 16 meanwhile only 2 (7%) of 30 women attending an obstetric clinic had antibodies greater than 16. Titres suggesting active chlamydial infection were found in prostitutes (95%), women with low genital infection (17%) and patients attending a cancer screening clinic (11%). In other hand, using immunofluorescence test with monoclonal anti Chlamydia trachomatis antibodies, 20 (45.5%) of the prostitutes were found antigen positive.

[Comparative study of immunologic techniques applied to the detection of herpes simplex virus (HSV)]. / Etude comparative des techniques immunologiques appliquées a la détection des virus herpes simplex (HSV).

Indirect immunofluorescence (IF), immunoperoxidase (IP) and seroneutralization tests were compared for detection and identification or Herpes simplex virus (HSV), directly in tissue smears or in cells inoculated with clinical materials. Detection and clear differentiation between the two HSV serotypes were obtained using rabbit immunoglobulin cross-absorbed with heterologous virus antigen. Immunofluorescent staining with specific monoclonal antibodies is as sensitive and more rapid than standard Vero cell cultures, for the laboratory diagnosis of HSV.

[Optimal detection of herpes simplex virus in clinical specimens preserved in transport media]. / Détection optimale du virus herpes simplex dans les échantillons cliniques conserves en milieu de transport.

The sensitivity of the methods used for HSV detection depends upon the stage and the transport of the collected lesions. High detection rates are achieved with early vesicular lesions rather with ulcers and scabs . Since HSV is heat-labile and to avoid loss of infectivity, specimens should be collected in transport medium and inoculated as soon as possible on the cell cultures.

[Evaluation of molecular hybridization tests and DNA restriction enzyme analysis for the detection and typing of herpes simplex virus (HSV)]. / Evaluation des tests d'hybridation moléculaire et d'analyse d'ADN a partir des enzymes de restriction pour la détection et le typage des virus herpes simplex (HSV).

Restriction enzyme analysis of DNA and blot hybridization tests were applied for the identification of 90 herpes simplex viruses isolated. The results obtained by those methods correlated completely with typing by monoclonal antibodies in an indirect immunofluorescent assay.

[Herpes simplex virus infections in Algiers]. / Infections a virus herpes simplex a Alger.

The purpose of this study was to determine the prevalence of herpes simplex virus antibodies among the population in Algiers. Anti-bodies to HSV1 are acquired rapidly between the ages of 1 and 6 years and 81.25% of the population is HSV1 seropositive by 15 years of age. Patients suffering from genital disorders possess HSV type 2 antibodies at a rate significantly higher (p less than 0.001) than in the control group.

Polio outbreak in Algeria: epidemiological, virological and vaccinational aspects.

During a poliomyelitis outbreak (October 1983) in El Oued territory (Algeria) 28 cases were diagnosed. All the patients were under 4 years old. The ratio of females to males was 0.33. No deaths occurred during this epidemic. 25 of the 28 polio cases were diagnosed by cell culture and 81% were polio type 1. The epidemiological survey established that the epidemic was due to the insufficiency of vaccination coverage, since the consumption of antipolio vaccine in the epidemic area had dropped by 25% from 1982 to 1983. 7 of the 28 polio cases had been given at least 3 injections of vaccine at the correct intervals. 5 of 8 vaccine samples from the epidemic area had an insufficient titre of polio type 1. These observations showed that the nature of the vaccine, whether killed or live virus, was less important for controlling poliomyelitis than providing medical and sanitary facilities to ensure good vaccination coverage.