Tissue specific distribution of Epstein-Barr virus (EBV) BZLF1 gene variants in nasopharyngeal carcinoma (NPC) bearing patients

Using EBV BNLF1 gene polymorphism, we have recently shown that, in NPC bearing patients, lymphocytes and tumor cells of the same individual were infected by different viruses. It appeared as a rule that EBV infection was by multiple strains in these immunocompetent, HIV negative patients. Our data did not detect any evident association between tumor cells and a particular BNLF1 variant. In the present paper, we extend our analysis to the BZLF1 gene of the viruses present in different sites of the same patients. Only two main variants of the BZLF1 gene were identified. Despite this very weak polymorphism of this locus, our results entirely confirm the very frequent occurrence of multistrain infections in these patients, and the presence of different EBV strains in tumor cells and lymphocytes from the same individual. However, in contrast to our results concerning the BNLF1 gene, the BZLF1 variants appeared to be cell type specific, one being associated mainly with epithelial or tumor cells and the other with lymphocytes. The possible reasons for this distribution are discussed.

Nosocomial outbreak of influenza virus A (H3N2) infection in a solid organ transplant department

BACKGROUND

There is a strong body of evidence in favor of influenza virus immunization in solid organ recipients. However, little attention has been devoted to other reservoirs, such as the patients' relatives and, at the time of hospital admission, to the healthcare workers.

METHODS

Analysis of the epidemiology of an outbreak of nosocomial influenza A in a solid organ transplant unit.

RESULTS

Four cases of influenza A virus infection were reported during a short 4-day outbreak in a 12 single-room transplant unit. None of the patients had been immunized against influenza. Three patients had not been visited by their relatives between admission and influenza infection. Three nurses, among the 27 healthcare workers, presented with clinical flu symptoms at times consistent with nosocomial transmission.

CONCLUSIONS

Because the prevention of influenza infection by vaccination warrants a global strategy to target the different reservoirs, we suggest that the modern policy of vaccinating solid organ patients should be extended both to their relatives and to the healthcare workers of transplant units.

Cytomegalovirus (CMV) prophylaxis by acyclovir in pre-transplant CMV-positive renal transplant recipients

Cytomegalovirus (CMV) infections, either primoinfection or reactivation, remain an important problem in organ transplantation. We therefore designed a prospective study in which pre-transplant CMV-positive renal transplant (RT) patients were randomized to receive for 3 months starting immediately after transplantation either acyclovir or nothing. Between April 1992 and January 1993, 53 cadaveric renal transplantations were performed in our institution. The immunosuppressive regimen included anti-thymoglobulins (ATG), azathioprine, steroids and cyclosporine A. Patients randomized in the acyclovir arm received the drug from day 1 to day 90 (D90) intravenously as long as the creatinine clearance was not above 10 ml/min and per os afterwards (3200 mg/day if the creatinine clearance was above 50 ml/min). CMV viraemia tests were systematically performed every 2 weeks until day 90 or when febrile episodes occurred. The patients were 53 adults who received a RT during the study period; 37 were included in the study of which 19 received acyclovir prophylaxis (group A) and 18, no prophylaxis (group B). The two groups did not significantly differ according to sex ratio, recipient's age, number of CMV-negative donors and number of days on ATG (10.76+/-6.16 vs. 8.28+/-4.21 days). There were significantly fewer viraemia episodes in group A (n = 6) than in group B (n = 13, P < 0.05); nevertheless, the percentage of symptomatic CMV viraemia was the same in both groups (35% vs. 38.5%). The onset of CMV viraemia occurred in the same period in both groups (39+/-13.8 days vs. 34.3+/-15 days; P = NS). The number of rejection episodes in the study period was the same in both groups (8 in each). We conclude from this prospective study that post-RT acyclovir prophylaxis reduces significantly the number of CMV viraemia episodes but does not delay their onset. Furthermore, it has no effect upon the percentage of symptomatic viraemias.

In nasopharyngeal carcinoma-bearing patients, tumors and lymphocytes are infected by different Epstein-Barr virus strains

Despite the fact that most adult humans worldwide are latently infected by the Epstein-Barr virus (EBV), only a very small percentage of them will develop an EBV-associated malignancy. We do not know whether this situation reflects the existence of more sensitive individuals or of particularly tumorigenic EBV strains. We postulated that if highly tumorigenic EBV strains did exist, they would be preferentially found in consistently EBV-associated tumors, such as nasopharyngeal carcinoma (NPC), and differ significantly from the strains present in other, non-pathological sites of the same patients. To test this hypothesis, we compared the BNLF1 gene of the EBV strains present in tumors and in "reservoir lymphocytes" of 6 NPC-bearing patients from Tunisia. Our results show that all of these patients were infected by more than 1 (and up to 7) EBV strains. Moreover, lymphocytes and tumor cells from the same individual were systematically infected by different viral strains. The origin and biological significance of these multistrain infections are discussed.

JC virus genotypes in France: molecular epidemiology and potential significance for progressive multifocal leukoencephalopathy

JC virus (JCV) induces progressive multifocal leukoencephalopathy (PML), especially in human immunodeficiency virus (HIV)-infected patients. Although JCV genotypes have primarily been associated with geographic patterns, a distinctive neuropathogenicity was recently attributed to genotype 2. A multicenter study was conducted to describe the distribution of JCV genotypes in France and to investigate correlations between genotypes and PML. Genotypes were determined by sequencing 494 bp in the VP1 capsid gene. Peripheral JCV was studied in 65 urine samples from 43 HIV-infected patients and from 22 control subjects. Genotypes 1, 4, 2, and 3 were detected in 52.3%, 30.8%, 12.3%, and 4.6% of the samples, respectively. In 56 brain or cerebrospinal fluid samples, PML-associated JCV of genotypes 1, 2, 4, and 3 was found in 66%, 19.7%, 8.9%, and 5.4%, respectively. Infection with JCV genotypes 1 or 2 was correlated with PML (odds ratio, 3.29). On the other hand, infection with JCV genotype 4 could represent a lower risk for PML.

Genomic variations in echovirus 30 persistent isolates recovered from a chronically infected immunodeficient child and comparison with the reference strain

Seven sequential isolates of echovirus type 30 (EV30) were recovered over 22 months from a child with severe combined immune deficiency syndrome. The nucleotide sequences of the 5' halves of the genomes (4,400 nucleotides) of the first (S1) and last (S7) isolates were determined and compared with that of the EV30 Bastianni reference strain, also determined in this study. In genome regions P1 and P2, 101 variations were identified between the two isolates. Synonymous differences far outnumbered nonsynonymous differences. Amino acid changes affected both capsid and nonstructural polypeptides (particularly 2B). The VP1 nucleotide sequences of the seven isolates were determined to analyze genome evolution during the chronic infection. In the phylogenetic tree, the seven isolates were directly related to the prototype strain in an individual monophyletic group, strongly suggesting that the chronic infection in the child arose from a single persistent EV30 isolate. Four lineages were observed in the persistent isolates. Isolates S2, S4, S5, and S6 were close relatives of one another, whereas isolates S1 and S3 formed individual lineages. Isolate S7, distantly related to all other isolates, formed the fourth lineage. These findings suggest the quasispecies nature of the genomes of the seven sequential EV30 isolates. Grouping of persistent isolates on the basis of replicative capacities was consistent with phylogenetic relationships. Overall, the results indicate that genetically related EV30 variants with different replicative capacities coexisted in a carrier state, probably in the gastrointestinal tract, during the infection of the child.

High Epstein-Barr virus serum load and elevated titers of anti-ZEBRA antibodies in patients with EBV-harboring tumor cells of Hodgkin's disease

Hodgkin's disease is commonly associated with EBV latent infection. The incidence of EBV reactivation (active infection or EBV infection with replicative cycle) was evaluated in a series of 30 patients with untreated Hodgkin's disease (except for one case with chronic lymphocytic leukemia) by quantitation of EBV DNA and titration of anti-ZEBRA antibodies in serum samples. DNA was detected in serum (>2.5 x 10(2) genomes/ml) in 15 of 30 patients and was more frequent in Hodgkin's disease with EBV-positive Reed-Sternberg cells (10/12) than in EBV-negative cases (5/18), (P< 0.01). Of interest was the demonstration that viremia correlated well with increased titers of anti-ZEBRA IgG and/or standard serological profiles of EBV reactivation (12/15), (P < 0.05). However the lack of EBV replicative cycle in Reed-Sternberg cells (negative for ZEBRA antigen and early antigen BHLF1) suggests that the viral replication occurs in a nonneoplastic cell compartment rather than in tumor cells. The measurement of EBV DNA loads and the titration of anti-ZEBRA antibodies shed new lights on the link between activation of EBV replication and Hodgkin's disease: these serological markers together with the determination of the EBV status of the tumor suggest that replication of the viral genome occurs with a decreased efficiency of the immune system, thus allowing progression of the tumor.

Prevalence of JC virus viraemia in HIV-infected patients with or without neurological disorders: a prospective study

Progressive Multifocal Leukoencephalopathy (PML) is a severe demyelinating disease, which is rapidly fatal and is due to JC virus (JCV) infection, which especially occurs in HIV-infected patients. To investigate JCV pathophysiology and to evaluate the predictive value of JCV detection in blood, we looked for JCV DNA in leukocytes and plasma of 96 patients without any neurological symptoms and 109 patients with neurological diseases, among whom 19 were suffering from PML. JCV genome was detected in about 18% of all patients, i.e. 15.6% of patients with central nervous system disorders except PML, 13.5% of patients without neurological symptoms and significantly more often in PML patients (47.6%). Both leukocytes and plasma were tested; in plasma, JCV DNA was found in 36.1% of positive patients and in cells in 80.5%. Surprisingly in seven instances only the plasma contained JCV genome. One-year follow-up of these patients showed that the absence of JCV DNA in blood was associated with a very low probability of developing PML (negative predictive value=0.99).

[Is laryngeal papillomatosis always juvenile?]

After recording an increased frequency of adult-onset recurrent respiratory papillomatosis, the authors propose a multicentric investigation. The aim of the investigation is to determinate the frequency of the new cases and their clinical form. The preliminary results confirm the increased frequency of the adult-onset form and show the possibility of a clinical form change.

CMV prophylaxis in high-risk renal transplant patients (D+/R-) by acyclovir with or without hyperimmune (CMV) immunoglobulins: a prospective study

In this prospective randomized study including 28 patients, we show that, in cytomegalovirus (CMV)-seronegative renal transplant recipients (R-) receiving a CMV-seropositive graft (D+), high doses of acyclovir (ACV, i.e. 3,200 mg/day) during the first 3 months after transplantation were as efficient as hyperimmune CMV immunoglobulins (CMV Igs) plus high doses of ACV regarding the prophylaxis of CMV primoinfection. Fifty-four percent of the patients in the ACV arm and 50% in the other arm presented at least one episode of viremia (n.s.). The incidence of CMV disease was 31% in the ACV group and 20% in the ACV + CMV Ig group (n.s.). By comparison with historical controls (no prophylaxis), we found that ACV with or without CMV Ig significantly delayed and significantly decreased the rate of CMV disease, although the severity score was not statistically different. Moreover, high doses of ACV were far less expensive than their combination with hyperimmune CMV Igs. Thus, until oral ganciclovir is available for the prophylaxis of primary CMV infection in renal transplant patients, we recommend the use of high doses of ACV for the first 3 months after transplantation in high-risk renal transplant patients, i.e. D+/R-.

[Chickenpox in pregnancy]

Chickenpox is rare during pregnancy (1 to 7 per 10,000). The infection can be severe for the mother and indirectly may affect the fetus. Before 20 weeks of amenorrhea, the varicella-zoster virus may be responsible for a rare embryofetopathy (incidence rate: 0.4 to 2%). After the 20th week of amenorrhea, fetal infection is not symptomatic, but it may lead to neonatal or infantile herpes zoster infection. During the perinatal period, a primary maternal infection may be responsible for severe neonatal varicella if delivery occurs prior to maternal antibody production. Practical guidelines are proposed according to the date of infection during pregnancy and prenatal diagnosis using amniocentesis and/or cordocentesis is discussed.

Efficacy and safety of lamivudine on replication of recurrent hepatitis B after cadaveric renal transplantation

BACKGROUND

The aim of this pilot study was to evaluate the efficacy and the safety of lamivudine therapy in hepatitis B virus (HBV)-positive/DNA-positive renal transplant recipients.

METHODS

Six HBV DNA-positive cadaveric renal transplant recipients ranging in age from 49+/-6 years were administered lamivudine, at 100 mg/day for a period of at least 6 months, on a compassionate-use basis. Lamivudine is the (-) enantiomer of 3'-thiacytidine, which is known to be a potent inhibitor of HBV replication. All of the patients but one were on cyclosporine-based immunosuppression.

RESULTS

The mean serum creatinine was 134+/-44 micromol/L. The mean duration of HBV infection was 230+/-54 months (156-288). All of the patients but one had high serum alanine aminotransferase levels (122+/-52 IU/L; range, 45-243). Histological evaluation showed the presence of either chronic active hepatitis (n=4) or cirrhosis (n=2). All of the patients but one were hepatitis B e antigen negative/hepatitis B e antibody positive, but none were coinfected with either hepatitis C virus or hepatitis D virus.

CONCLUSIONS

Lamivudine therapy was associated with (i) a normalization of alanine aminotransferase levels in four of five patients when these levels were increased at the beginning (n=5); (ii) a rapid disappearance of HBV DNA from the serum (detected by hybridization) in all of the patients; (iii) the negativity of HBV DNA by polymerase chain reaction in four patients; and (iv) no change in renal function and in proteinuria when present (one patient). Finally, no adverse effects were noted. When lamivudine therapy was stopped for four patients after 6 months, it was associated with a biochemical and virological relapse within the weeks that followed. Lamivudine therapy was therefore resumed for these patients.

Prevalence of antibodies to hepatitis C virus and correlation with liver disease in renal transplant patients

We studied the prevalence of hepatitis C virus (HCV) infection in 350 renal transplant (RT) patients with a functioning graft. The determination of HCV infection was based upon second-generation ELISA tests (ELISA-2, Abbott) confirmed by second-generation RIBA tests (RIBA-2, Chiron), including the proteins C22-3, C100-3, C33-C and 5-11. Three hundred and sixteen of these RT patients were on ciclosporin A (CsA) therapy with or without steroids (CS) and azathioprine (AZA); 34 received conventional immunosuppression. Eighty-seven RT patients were found to be HCV-positive (2.5%) when assessed by ELISA-2 tests; RIBA-2 was positive in 61 cases and 'indeterminate' in 26. Most of the HCV-positive patients had antibodies against C22-3 (94%), whereas antibodies against nonstructural antigens (C100-3, C33-C) were observed in 18 and 70% of cases, respectively. More than 88% of the HCV-positive patients were already HCV-positive before renal transplantation. Risk factors of developing HCV infection included: (i) the time on dialysis; (ii) the number of blood transufsions before transplantation, and (iii) the number of previous graft(s). There were significantly more HCV-positive patients among those on conventional immunosuppressive therapy (16 of 39) than among those on CsA (71 of 311; p < 0.02). Of those who where HCV-positive before transplantation, and for whom liver enzyme (LE) results were available (n = 68), 40 had either a normal or a transient increase in alanine aminotransferase (ALT) levels at that time, whereas 28 had a chronic increase in serum ALT +/- gamma-glutamyltranspeptidase levels. After transplantation, there was biochemical evidence of chronic liver disease in 33 patients (48.5%). Interestingly, 41 and 64% of those with respectively normal and increased LEs before transplantation presented with a biochemical chronic liver disease after RT. Surprisingly, 36% of those with a pretransplantation increase in ALT had normalized aminotransferase after transplantation. The daily doses of AZA, CS (i.e. prednisolone) were not statistically different between HCV-positive RT patients on conventional therapy (group A) and those on CsA (group B). Moreover, within each group, the daily doses of AZA, CS or CsA were not statistically different between those with a chronic increase in LEs and those with normal LEs. The percentage of HCV-positive RT patients with chronic abnormal LEs was not different between groups A and B. Surprisingly, the patients who were treated at least once for acute rejection with methylprednisolone pulses had a significantly lower incidence of chronic increases in LEs. Nine patients seroconverted for HCV after transplantation: 6 experienced a chronic increase in LEs. Finally, 7 of 87 patients were coinfected by HBV, all of them had a chronic increase in LEs. These results emphasize the fact that ALT alone cannot be used as a surrogate marker for chronic HCV infection in transplantation patients, thus a liver biopsy is required before and a few years after RT to assess liver damage in this population.

Intra-uterine fetal death following maternal varicella infection

The association of varicella and pregnancy is very rare since 90% of women of reproductive age are immune. In the literature, a fetal varicella syndrome has been described characterized by multiple congenital malformations. We report here a case of intrauterine fetal death following maternal varicella at 17 weeks amenorrhea, with virological proof of fetal contamination. Because of the rarity of this association and by the same token of the fetal contamination during maternal varicella, the management during pregnancy rests essentially on a valid ultrasonic surveillance.

Inflammatory pseudotumor of the liver. Evidence for follicular dendritic reticulum cell proliferation associated with clonal Epstein-Barr virus

We describe an "inflammatory pseudotumor" of the liver that, which on detailed investigation, proved that the spindle-cell component of this lesion is derived from follicular dendritic reticulum cells (FDRC). This contention is supported by morphologic observations and by immunophenotype. The FDRC population contain Epstein-Barr virus (EBV). It is known that FDRC express the EBV receptor CD21. In this particular case, the FDRC contained clonal EBV genomes, EBV RNA (EBER) transcripts, and expressed EBV latent membrane protein (LMP1). DNA sequencing of PCR products showed three point mutations compared with the standard LMP1 sequence of the EBV strain B95-8. The findings in this case corroborate those of other investigators concerning the possible role of EBV in the development of some inflammatory pseudotumors, including the recent production of functionally active EBV-transformed FDRC-like cell lines. This association could prove instructive in delineating the histogenesis of these tumors and further assist in making prognostic and therapeutic decisions.

Measurement by the polymerase chain reaction of the Epstein-Barr virus load in infectious mononucleosis and AIDS-related non-Hodgkin's lymphomas

A polymerase chain reaction (PCR) assay for the detection of Epstein-Barr virus (EBV) sequences in various clinical samples, especially peripheral blood leukocytes (PBL) and serum, was carried out and the results obtained were compared with specific EBV serology. One hundred seventy patients were enrolled in the study: 89 healthy blood donors, 22 asymptomatic patients, 36 individuals with primary EBV infection (including 19 patients with infectious mononucleosis [IM]), 22 HIV-infected subjects (including 4 with hairy oral leukoplakia, 3 with central nervous disorders, and 15 with non-Hodgkin's lymphoma). All the serum samples from the healthy blood donors were negative. In patients with IM and in AIDS-non Hodgkin's lymphoma (ARNHL), PCR was strongly positive in leukocytes (> 2,000 genome equivalents/10(4) cells), which was correlated with detectable amounts of EBV DNA in serum. The overall positivity rate of PCR in serum was 58.8%, 68%, and 73% of cases for non-IM primary EBV infections, IM, and ARNHL, respectively. In two cases of EBV primary infection, the viral DNA was detected in serum, respectively 1 month and 2 months before IgM positivity and IgG rise. In one case of ARNHL followed up for several months, PCR (viral load of 2,000 genome equivalents/10(4) cells) became positive concurrently with appearance of lymphoma. In immunocompromised individuals, PCR EBV, if carried out in larger prospective studies, could be considered as a tumor marker, useful for predicting EBV-driven lymphoma and follow-up therapy.

[Guillain-Barré syndrome associated with cytomegalovirus infection after kidney transplantation]

The Guillain-Barré syndrome associated with cytomegalovirus infection is a recognized entity of unknown pathogenesis. We observed two characteristic cases with acute polyradiculoneuropathy which occurred after renal transplantation. Both patients fulfilled the diagnostic criteria for Guillain-Barré syndrome: tetraparesis with diffuse areflexia and moderate sensorial signs, high protein level in cerebrospinal fluid without cellular reaction, slow or blocked nerve conduction and partial cure after several months delay. In two-thirds of such cases, the syndrome follows an episode of infection. Cytomegalovirus has been recognized as a possible association. The demyelinating polyradiculoneuropathy induced by cytomegalovirus has been reported essentially in immunodepressed patients infected with the human immunodeficiency virus in whom a pathogenic role for cytomegalovirus in peripheral nerves has been suggested. In our two cases, the cytomegalovirus infection occurred before onset of the acute polyradiculoneuropathy. In both cases, specific IgM antibodies and clear IgG positivization occurred before the first signs of neurological impairment even though neither the virus nor specific antibodies could be concomitantly detected in the cerebrospinal fluid. Despite the frequency of cytomegalovirus infections in transplant recipients, to our knowledge, only 9 cases of Guillain-Barré syndrome after transplantation have been reported and the exact mechanism remains to be ascertained. These two cases suggest that the onset of the Guillain-Barré syndrome after renal transplantation was closely related to cytomegalovirus infection. Adequate measures should be taken to quickly diagnose such cases in order to instore rapid treatment for the polyradiculoneuropathy. In addition, this particular situation of post-transplantation onset might help better understand the exact role of cytomegalovirus infection in the Guillain-Barré syndrome.

Epstein-Barr virus (EBV) replicative gene expression in tumour cells of AIDS-related non-Hodgkin's lymphoma in relation to CD4 cell number and antibody titres to EBV

OBJECTIVE

To determine whether activation of Epstein-Barr virus (EBV) replication in tumour cells of AIDS-related non-Hodgkin's lymphoma (ARNHL) is correlated with CD4+ cell counts and influences antibody response to EBV [anti-Z Epstein-Barr replicative activator (ZEBRA), anti-early antigen (EA), anti-viral capsid antigen (VCA)].

DESIGN

Retrospective study based on immunohistochemistry and in situ hybridization to detect EBV replicative gene products in tissue samples from patients affected by ARNHL and correlation with CD4+ cell counts and results of EBV serology (including anti-ZEBRA activity) in sera from the same patients.

METHODS

Seventeen out of 22 cases of ARNHL were selected for the presence of EBV [Epstein-Barr early region (EBER) RNA-positive]. Immunohistochemistry was performed with anti-ZEBRA, anti-EA-restricted, anti-VCA antibodies and in situ hybridization with BHLF1/NotI oligoprobes on tumour samples. Results were statistically correlated with those of CD4+ cell counts (17 out of 17) and with anti-EBV antibody titres (13 out of 17) assessed using standard immunofluorescence method and enzyme-linked immunosorbent assay procedure using recombinant ZEBRA protein and synthetic peptides as antigens.

RESULTS

BZLF1 (ZEBRA) or early gene products (EA-R and EA-D/BHLF1/NotI) were detected in a small proportion (< 0.01-5%) of tumour cells in eight of these 17 cases by immunohistochemistry and in situ hybridization. Demonstration of replicative gene expression did not correlate with either low CD4+ cell counts (P > 0.05) or anti-EBV antibody titres (P > 0.05). Anti-ZEBRA activity was not significantly increased in patients affected with ARNHL, the cells of which expressed replicative gene products (P > 0.05).

CONCLUSION

The degree of immunodeficiency does not clearly enhance replicative gene expression in tumour cells of ARNHL. EBV serology, including anti-ZEBRA activity, is not a reliable tool for predicting the occurrence of such proliferations.

Detection of Epstein-Barr virus messenger RNA in Reed-Sternberg cells of Hodgkin's disease by in situ hybridization with biotinylated probes on specially processed modified acetone methyl benzoate xylene (ModAMeX) sections

Microscopic intracellular detection of Epstein-Barr virus (EBV) messenger RNA in Reed-Sternberg cells of Hodgkin's disease (HD) was possible by in situ hybridization, in tissue sections prepared by a method termed modified acetone methyl benzoate xylene (ModAMeX). The ModAMeX method was initially developed for simultaneous optimal preservation of leucocyte differentiation antigens and morphology. Two biotinylated DNA probes, corresponding to the same BamHI-W (internal repeat) of the EBV genome were used. EBV mRNA was detected in neoplastic cells in 16 of 54 (30%) lymph node biopsy specimens from usual subtypes of HD (lymphocyte predominance, 0/5; nodular sclerosis, 4/22; mixed cellularity, 12/26; unclassified, 0/1). EBV mRNA was also detected in the lymph node biopsy of 1 additional human immunodeficiency virus (HIV)-related case of HD (mixed cellularity) and in 2 of 4 cases of B-cell lymphomas occurring in patients with acquired immunodeficiency syndrome (AIDS). In other non-Hodgkin's lymphomas, EBV mRNA was detected in only 1 of 41 cases. Cases of HD positive for EBV mRNA were immunostained by CD30 and CD15 antibodies. The hybridization signals were exclusively restricted to Reed-Sternberg cells and variants. When analyzed retrospectively, no statistically significant correlation emerged between hybridization findings, EBV serology, or disease outcome over the 3 years of the availability of ModAMeX technique. The findings support the contention of a direct role of EBV in the pathogenesis of HD, at least in some cases.

Identification of a novel EBV-induced membrane glycoprotein of 43 kDa with H667 MAb

Using purified B95-8 Epstein-Barr virus (EBV), a MAb designated H667 was produced. We demonstrated by indirect membrane immunofluorescence (IF) on six EBV producer cell lines and by immunoelectron microscopy that H667 reacted with a membrane antigen. H667 recognized a 43-kDa EBV protein (p43) as determined by immunoblotting using purified EBV from the six producer cell lines. Phosphonoacetic acid treatment of B95-8 cells was associated with the disappearance of p43, indicating that it was a late antigen. This antigen was shown to be a glycoprotein by incorporation of [14C]glucosamine and was shown to contain an N-asparagine-linked glycosyl group by its sensitivity to tunicamycin. It was named gp43. The H667 MAb inhibited B95-8 EBV cord blood lymphocyte transformation only when a low inoculum was used but failed to inhibit EA induction in Raji cells by P3HR1 EBV. Human sera reactivity against the gp43 antigen was studied. By the immunoblotting method, using H667 immunoaffinity chromatography-purified gp43, we showed that 70.9% of the human sera tested had antibodies directed against gp43. By IF blocking tests, we found that only 12.5% of the sera tested were reactive, indicating that the epitope corresponding to the H667 MAb was not the most immunogenic gp43 epitope.

Production of anti-B monoclonal antibodies (DBB.42, DBA.44, DNA.7, and DND.53) reactive on paraffin-embedded tissues with a new B-lymphoma cell line grafted into athymic nude mice

A new B-lymphoma cell line (DEAU-cell line) was established from a diffuse large-cell lymphoma (centroblastic type) and was successfully grafted in athymic nude mice. Monoclonal antibodies (MoAbs) were generated using splenocytes of DEAU-tumor bearing mice. Before the fusion experiments, cellular immunity of the mice bearing growing DEAU tumors was restored by injection of spleen cells from conventional Balb/C mice. Spleen cells from conventional Balb/C mice immunized with DEAU-cell line were also used for the generation of MoAbs. Four MoAbs (DBB.42 and DBA.44 from normal Balb/C mice, and DNA.7 and DND.53 from athymic nude mice) were investigated because they identified B-cell-associated antigens not destroyed by fixatives. DBB.42 recognized a pan-B cell-associated antigen (molecular weight (mol wt) = 45 Kd). DBA.44 detected a B-cell antigen (mol wt not determined) expressed on a subpopulation of B lymphocytes in the mantle zone of lymphoid follicles. DNA.7 also defined a B-cell antigen (43 Kd) mainly expressed on germinal center cells. Similarly, DND.53 recognized a B-cell antigen (two bands of mol wt 20 Kd and 35 Kd, respectively) mainly expressed on germinal center cells and mantle zone lymphocytes and interdigitating reticulum cells in the paracortical area. Major differences were found in the reactivities of these MoAbs on malignant lymphomas. DBB.42 was positive with almost all B-cell lymphomas and some T-cell lymphomas. Within the group of low-grade B-cell lymphomas, DBA.44 reacted principally with hairy-cell leukemia. DNA.7 reacted mainly with high-grade B-cell lymphomas with a weak positivity in low-grade B-cell lymphomas. DND.53 reacted with all but one B-cell lymphoma, cells of histiocytosis X, and Reed-Sternberg cells. These findings indicate that new MoAbs can be generated by using spleen cells from athymic mice bearing human tumors as well as by new lymphoid cell lines. The MoAbs so generated, as in the present study, are deemed potentially useful for the recognition of B-cell lymphomas in routine diagnostic histopathology. In addition, DND.53 could be of value for the diagnosis of histiocytosis X and the detection of Reed-Sternberg cells in Hodgkin's disease.

Characterization of a 75-kDa Epstein-Barr virus capsid protein using a new monoclonal antibody H250

A monoclonal antibody (mAb) designated H250, directed against an Epstein-Barr virus (EBV) capsid antigen, was obtained following immunization of BALB/c mice with naked particles from the producer cell line B95.8. This antigen was present in the producer lines B95.8, P3HR1, M81, RI and CA, and absent from the non-producer lines BJAB, Raji and 1022. H250 did not inhibit the transformation of cord blood lymphocytes by the B95.8 virus, nor did it inhibit EA induction on Raji cells by the P3HR1 virus. In addition, H250 showed no fluorescence on living B95.8 cells. This indicates that H250 does not recognize a membrane antigen. By indirect immunofluorescence, no fluorescence was observed on induced Raji cells or on PAA-treated B95.8 cells. Thus, H250 recognized a late antigen of the EBV virus replication cycle. Agglutination of naked virus by H250 showed it was directed against a capsid antigen. Positive fluorescence was observed on cells treated with tunicamycin, indicating that H250 recognized a protein. The molecular weight of this protein was obtained by Western blot and was approximately 75 kDa. The blocking tests carried out with H250 seemed to indicate that this Ab appeared late in patient sera during primary infection.

[Severe Epstein-Barr virus infection in an infant]

A 11 month-old boy, without any informative familial pedigree, was admitted for peritonitis after intestinal perforation, associated with signs of pseudolymphoma and histiocytic activation. He developed later unexplained gastrointestinal bleeding and interstitial pneumonitis, which spontaneously improved. All infectious and immunologic studies were negative. Epstein-Barr Virus was found in throat, lungs and blood, whereas the specific antibodies production was delayed. No abnormality was detected 18 months later, except for a disappearance of vaccinal antibodies.

Biochemical and ultrastructural findings in Epstein-Barr virus-transformed lymphoid cell lines from type 1 Gaucher disease

Lymphoid cell lines established by Epstein-Barr Virus (EBV)-transformation of peripheral blood B-lymphocytes from patients affected with type 1 Gaucher disease showed a severe deficiency of glucosylceramide-beta-glucosidase activity (residual activity around 15%-30% of control activity). Ultrastructural investigations showed, in these lymphoid cell lines from type 1 Gaucher disease, the presence of numerous membrane-bound inclusion bodies characteristic of Gaucher cells.

Epstein-Barr virus serology in bone marrow transplantations: a one-year retrospective study with detection of EBV IgM-VCA-specific antibodies

The specific antibody response to Epstein-Barr virus (EBV) antigens of 41 bone marrow transplant recipients with leukemia or aplastic anemia was examined retrospectively by immunofluorescence test (IF) over 1 year. We observed high titers (greater than 640) of IgG-viral capsid antigen (VCA) with emergence of IgG-early antigen (EA) and frequent absence or low levels of Epstein-Barr nuclear antigen (EBNA) antibodies. After absorption to remove rheumatoid factor (RF), five of the 41 recipients had IgM-VCA antibody to EBV, which appeared between weeks 26 and 48 after BMT and persisted for 1-4 months. No heterophil antibodies were detected in these sera, and none of the five recipients had a history of infectious mononucleosis.

Molecular forms of beta-N-acetylhexosaminidase in Epstein-Barr virus-transformed lymphoid cell lines from normal subjects and patients with Tay-Sachs disease

In whole leukocytes and in lymphocytes from normal subjects, the percentage activity of heat-stable beta-N-acetylhexosaminidase (30 +/- 5% and 45 +/- 5%, respectively) was higher than in the transformed lymphoid cell line (19 +/- 3%). In Tay-Sachs transformed cells as well as non-transformed beta-N-acetylhexosaminidase was almost completely heat-stable (95 - 98%). In the transformed cells from normal subjects, the beta-N-acetylhexosaminidase B (Hex B) activity (5% of total) was significantly lower than in blood lymphocytes (average 25 - 30% of total activity), whereas Hex A and Hex I were similar in the either cell type. Blood lymphocytes and lymphoid cell lines established from a Tay-Sachs patient lacked heat-labile Hex A and expressed high heat-stable Hex I and Hex B activities (3-6-fold). After neuraminidase treatment, Hex A peak sharpened while Hex I peaks switched to higher pI than normal Hex I, in the region of Hex B. PreHex A/S pI was not affected. Hydrolytic properties using the both substrates (4-methylumbelliferyl-2-acetamido-2-deoxy-beta-D-glucopyranoside and 4-methylumbelliferyl-2-acetamido-2-deoxy-beta-D-galactopyranoside) of each molecular form were similar in transformed and non-transformed cells. Data derived from the use of a mixture of substrates were consistent with the model which proposes a common active site for either substrate in the case of preHex A, Hex B and Hex I, but not for Hex A. Thus Epstein-Barr virus-transformed lymphoid cell lines represent an accurate model system for studies on Tay-Sachs disease.

Prospective study of Epstein Barr virus (EBV) infection during pregnancy

The serological EBV profile of 2752 pregnant women characterized in most cases a latent EBV carrier state. The pregnancy rarely reactived this latent infection. But mothers with an "active" EBV serology gave birth more frequently than others to still born or defective bodies. In six pregnancies with primary EBV infection, detected early, four presented a pathological delivery. Furthermore the follow up of the EBV profile in 719 mothers revealed a significant relation between defective births and persistent EA antibodies. The role of EBV has yet to be precisely defined but the early detection of anti-EA EBV antibodies should be considered as a risk indicator in the management of pregnancy.

The Epstein-Barr virus (EBV) in human pathology. II. Serologic profiles of EBV infections

Antibodies to EBV induced intracellular antigens, (VCA, EA, NA) and VCA-IgM antibodies have been investigated to define EBV serologic profile of 245 individuals. This profile was a first studied in EBV primary infections. In infectious mononucleosis, the efficiency of EBV serodiagnosis is lower than Paul Bunnel Davidsohn reaction (PBD) : primary infection profile is only characterised in 80% of the positive PBD infectious mononucleosis (IM). On the other hand, EBV antibodies are preponderant for diagnosis in other clinical manifestations of EBV primary-infection were PBD is not alwasy positive (47%). EBV antibodies of patients with various diseases and antibodies of normal subjects show different profiles. By interpretation of these profiles one discuss the possibility to characterize reinfection, and either latent or active persistant infection.