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The sodium salts of 2-difluoromethyl-phenyl-alpha-ketoside of N-acetyl-neuraminic acid (compound 1) and of 4-difluoromethyl-2-methoxy-phenyl-alpha-ketoside of N-acetylneuraminic acid (compound 2) were designed as potential mechanism-based inhibitors of sialidase. In vitro both of these compounds competitively inhibited the sialidases of Clostridium perfringens and of influenza virus A/HK/1/68. Inhibition was irreversible with the sialidase of Clostridium perfringens whereas it was reversible with that of A/HK/1/68. Compound 2 did not inhibit the hemagglutinin of the virus but exhibited significant anti-influenza activity when added to the medium of Madin-Darby canine kidney (MDCK) cells infected by influenza virus. In non-infected MDCK cells no inhibition of cellular sialidase was observed. Compound 2 did not block primary infection, but inhibited the release of progeny virus from infected cells. Even after 8 passages in its presence, no resistant strains were detected. Because of its high Ki (8 x 10(-5) M) compared to the low Ki (1' x 1(-10) M) of 4 guanidino-Neu 5 Ac 2en and its reversible inhibition of viral sialidase, its development as an anti-influenza agent is no longer envisaged. Nevertheless, as a mechanism-based irreversible inhibitor of the bacterial enzyme, it could at least be useful for investigating the intrinsic role of sialidase in infections caused by this strain.

The relationship between oxidative stress and neuronal cell death has been suggested for many years. To understand the influence of oxidative stress on neuronal cell death, we investigated the influence of oxidative stress on DEV cells, a human glial cell line. Using enterovirus infection and/or malnutrition to induce oxidative stress, our results demonstrate that those stressors severely influence the antioxidant defense system in DEV cells. Although the expression of mitochondrial manganese superoxide dismutase (MnSOD) in DEV cells was significantly increased in acute infection with viral and nutritional stress, in persistent infection and nutritional stress, the expression of the MnSOD was drastically downregulated. We believe that this downregulation of MnSOD expression in the chronic stress model is due to repression of antioxidant defense. The downregulation of the MnSOD expression may lead to an increase of free-radical production and thus explain why the cells in the chronic stress model were more vulnerable to other oxidative stress influences. The vulnerability of DEV cells to additional stress factors resulted in progressive cell death, which may be analogous to the cell death in neurodegenerative diseases.

Rapid and efficient uptake of glutamate via the high-affinity glutamate transporter EAAT2 is important for limiting glutamate-mediated excitotoxicity involved in neuronal death. Furthermore, there is evidence of altered glutamate uptake and catabolism in motor neuron diseases. Such a defect has been reported in amyotrophic lateral sclerosis, the major motor neuron disease, and was associated with impairment in EAAT2 processing. We recently reported the presence of enterovirus genome specifically in the anterior horn of amyotrophic lateral sclerosis cases, suggesting the involvement of a chronic/persistent enterovirus infection in amyotrophic lateral sclerosis. To investigate a putative link between enterovirus infection and the glutamate-mediated excitotoxicity observed in amyotrophic lateral sclerosis, we developed an in vitro model consisting of a human glial cell line infected with ECHOvirus 6, one of the enteroviruses with sequences closely related to those detected in patients with amyotrophic lateral sclerosis. In these glial cells, an ECHOvirus 6 chronic infection was established, resulting in altered extracellular glutamate uptake. This correlated with an aberrant splicing of the EAAT2 pre-messenger ribonucleic acid and a significant loss of EAAT2 protein expression, similar to that observed in patients with amyotrophic lateral sclerosis. These results provide convincing evidence that an enterovirus chronic/persistent infection may alter glial glutamate uptake and catabolism. As enteroviruses are extremely common human pathogens, they may act as a trigger in the development of certain motor neuron diseases, such as amyotrophic lateral sclerosis.

H3N2 and “avian-like” H1N1 subtypes have circulated in European pigs since the mid- to late 1970s. Following reassortment to acquire six internal genes of the H1N1 viruses in the early 1980s, the H3N2 viruses have evolved to produce antigenically distinguishable variants. Sw/Finistere/127/99, isolated from a pig in January 1999, was shown to be closely related in antigenic and genetic characteristics to contemporary human A/Sydney/5/97-like viruses, and may represent the emergence of another “human-like” virus in European pigs. The H1N1 viruses circulating in pigs in France have evolved gradually over the past 20 years, but are in general closely related to early isolates such as Sw/Finistere/2899/82. An antigenically distinct variant, represented by Sw/Ille et Vilaine/1455/99, represents a significant drift from other recent French H1N1 viruses. Most of the H1N2 reassortant viruses isolated in France and Italy since 1997 were shown to be genetically similar to the H1N2 viruses which have become prevalent in the U.K., but to exhibit significant variation in antigenicity. Genetic reassortment between H1N2 and H1N1 viruses has also contributed to the recent increase in diversity of viruses circulating in pigs in Europe, and emphasizes the potential difficulties in controlling influenza by vaccination. Since most of these swine viruses are resistant to amantadine, they provide an increasing pool of amantadine-resistant M genes for potential incorporation into future human viruses.

The pathophysiology of chronic hepatitis in rabbits infected with coxsackievirus B5 (CVB5), (strain Mitchell) was investigated. Three-week-old male New Zealand White rabbits were inoculated intraperitoneally with 1 x 10(5) plaque forming units of virus. Every 3 months for 15 months postinoculation (p.i.) groups of animals were sacrificed for the following tests: interleukin (IL)-6, tumor necrosis factor-alpha (TNF-alpha) and interleukin (IL)-beta cytokine levels by enzyme-linked immunosorbent assay (ELISA); splenic natural killer (NK) cell function; sequence of a 154-bp section of the 5' noncoding region; antihepatocyte autoantibodies; histologic examination; in situ polymerase chain reaction (ISPCR) of the liver; neutralizing antibody response to CVB5; and viral cultures of liver, spleen, blood, brain, heart, skeletal muscle, and pancreas samples. Histologic evidence of hepatocyte necrosis was evident at each time point, although few inflammatory cells were seen. Liver samples were positive at each time by ISPCR, with viral nucleic acid localized to hepatocyte cytoplasm. Other cells in the liver did not stain. No hepatocyte autoantibodies were detected, and there was no elevation of intrahepatic cytokine levels compared to uninfected controls. There were no mutations in the virus over time. A vigorous neutralizing antibody response to CVB5, Mitchell was generated, but splenic natural killer (NK) function and numbers of splenic NK cells were significantly decreased. Virus culture was positive at 3 months, but negative at further time points. Cultures were negative at 3 months for the other tissues tested. Thus, CVB5, Mitchell causes a chronic hepatitis in rabbits, with virus limited to hepatocyte cytoplasm and no evidence of autoimmunity.

The use of polymerase chain reaction (PCR) for the detection of cytomegalovirus (CMV) in bronchoalveolar lavages (BAL) of immunocompromised patients was evaluated. Firstly, PCR was compared to conventional cell culture (CCC) and shell vial assay (SVA) in 65 BAL received in our laboratory on a routine basis. Sensitivity and specificity of the PCR were 100% and 87.2% respectively. The PCR method was then applied to the monitoring of 55 BAL from nine lung transplant recipients. The data illustrate the excellent sensitivity of PCR. However the predictive value of the test for the occurrence of a symptomatic infection was weak.

Resume La place des virus dans l'etiologie des rhinopharyngites et otites aigues chez l'enfant de 0 a moins de 5 ans a ete evaluee au cours d'une enquete prospective effectuee sur 2 sites (Bordeaux et Lyon) dans l'hiver 1995–96. Les enfants vus en medecine de ville ou en consultation hospitaliere ont subi un prelevement nasopharynge achemine au laboratoire dans un milieu de transport et examine par des tests immunologiques et par mise en culture rapide. Aux 116 prelevements obtenus dans cette enquete (ORPHE), essentiellement dans les consultations hospitalieres, nous avons pu ajouter des prelevements effectues en medecine de ville dans le cadre des reseaux de surveillance de la grippe (GROGS). Globalement, 34,4 % des 285 patients atteints de rhinopharyngite febrile avaient une infection virale (Influenza A, B, VRS, Parainfluenza, ADV, Rhinovirus, Echovirus, HSV) et 29,1 % des 141 patients presentaient une otite ou une otalgie. Les otites a virus Influenza A et a VRS ont naturellement coincide avec les epidemies. Ces resultats sont en accord globalement avec les quelques donnees de la litterature. Les differences d'incidence observees tiennent : au recrutement des enfants, a leur âge, aux variations epidemiologiques des virus et a la performance des tests virologiques. Leur qualite pourrait etre amelioree par l'usage des techniques d'amplification genique. La mise en evidence de virus dans le liquide d'oreille moyenne, les infections experimentales animales, et chez l'homme adulte, confortent les hypotheses pathogeniques : le virus seul peut causer une OMA, frequemment il y a association virus + bacterie pathogene (sans qu'il y ait forcement suppuration), et l'infection virale est a l'origine de l'infection bacterienne par son action sur les cils des cellules, et en favorisant la colonisation bacterienne. La prevention par vaccination de l'infection virale chez l'enfant (grippe) a reduit significativement l'incidence de l'OMA en periode d'epidemie de grippe. Mycoplasma pneumoniae est associe a des rhinopharyngites et a des otites dans 3,5 % des cas et il est frequemment detecte en association avec des virus. Chlamydia pneumoniae n'a ete detecte que 3 fois.

The current study compares the sensitivity of RNA extraction using magnetic beads versus that of a standard extraction method. Streptavadin-coated magnetic beads were labelled with a biotinylated, enterovirus-specific oligonucleotide. RNA was extracted using labelled beads or guanidium thiocyanate-phenol-chloroform from 1, 0.1 and 0.01 TCID50/100 microliters of stock coxsackievirus types A9 and B3, echovirus type 11, enterovirus type 70 and poliovirus type 1. Each strain was tested three times. RNA extraction using magnetic beads was50% faster than the standard method. The RNA was amplified using RT-PCR, and the products were detected using agarose gel electrophoresis; 6/15 and 7/15 samples at an initial concentration of 0.01 TCID50/100 microliters were detected using magnetic beads or standard extraction, respectively. Negative-stain electron microscopy was used to determine that 0.01 TCID50/100 microliters of coxsackievirus B3 contained approximately 3 genomes. Thus, use of magnetic beads labelled with an enterovirus-specific oligonucleotide was less toxic, more rapid and as sensitive as the current standard RNA extraction method.

Thirteen laboratories participated in blind tests of a panel of 20 coded cerebrospinal fluid specimens (7 uninfected samples, 3 samples infected with 1 50% tissue culture infective dose [TCID50]/0.1 ml [nonenterovirus strains], and 10 samples infected with 10, 1, or 0.1 TCID50/0.1 ml [three different enterovirus serotypes]) on the Amplicor enterovirus PCR assay (Roche Diagnostic Systems). The panel was also evaluated by in-house PCR (two nested-PCR and three one-step PCR assay) or tissue culture (eight laboratories). The viral load was shown to influence greatly the sensitivity of the assay. The average sensitivity of the Amplicor test ranged from 67 to 98% for viral titers of 1 to 10 TCID50/0.1 ml, respectively; titers of 0.1 TCID50/0.1 ml resulted in a sensitivity of only 16%. The overall specificity of the Amplicor test was 98%. The Amplicor assay compared favorably to the five in-house PCR tests (no significant difference in either sensitivity or specificity) and was much more sensitive than tissue culture (P < 0.001), even for high viral loads. It was easy to perform, rapid (about 6 h), well-standardized, and appeared to be suitable for the diagnosis of enterovirus meningitis on a routine basis in laboratories trained in molecular biology techniques.

SUMMARYAn epidemiological study of hepatitis A and enteroviruses was conducted in a military diving training school, by evaluating the viral contamination of water using an ultrafiltration concentration technique, and assessing seroconversion and the presence of virus in stool specimens obtained from 109 divers and 48 controls. Three of 29 water specimens were positive for enterovirus by cell culture and 9 by molecular hybridization. There was little or no risk of virus infection during the training course (49 h exposure) because there was no significant difference between divers and controls for both viral isolation and seroconversion. However, a higher percentage of coxsackievirus B4 and B5 seropositive divers suggests that these were more exposed during previous water training. No hepatitis A virus (HAV) detection and no seroconversion to HAV was observed. The rate of HAV seropositive subjects was 17% in this 24·5-year-old population

Ten sequential post-treatment herpes simplex virus type 1 (HSV-1) isolates were obtained from an immunocompromised patient whose infection, during prolonged treatment, became unresponsive to acyclovir (ACV). Of the ten isolates, eight later isolates were resistant in vitro to ACV and ganciclovir (DHPG), but remained sensitive to 9-β-D-arabinofuranosyladenine (ara-A) and phosphonoformate (PFA). Biochemical characterization of plaque-purified clones of the resistant isolates revealed an altered thymidine kinase (TK) substrate specificity phenotype. The comparative nucleotide sequence analysis of polymerase chain reaction (PCR)-amplified DNA encoding the TK genes of one sensitive and two resistant clones showed a single mutation at nucleotide 527. This change would result in a substitution of arginine by glutamine at residue 176 of the polypeptide, a mutation previously observed in a laboratory isolated variant, SC16 Tr7 (Darby et al., 1986).

The relative importance of the host immune response to various antigenic and functional sites on the HN glycoprotein of Sendai (6/94) virus for protection in vivo, was evaluated in mice passively immunized with monoclonal antibodies to HN and then intranasally challenged with infectious virus. Five neutralizing monoclonal antibodies reacting with distinct antigenic sites and exhibiting different reactivity patterns were selected. All of them were able to prevent entirely the growth of virus in the lungs of experimental animals injected with appropriate dilutions of monoclonal antibody. The calculation of correlation coefficients between the reduction of virus in the lungs of immunized mice and the amount of antibody, expressed in terms of hemagglutination inhibition, hemolysis inhibition or neutralizing units, showed a high degree of correlation (r = 0.89) with neutralization and a lack of correlation (r = 0.44) with hemagglutination inhibition. In parallel a minimum threshold value for protection equivalent to 2 x 10(3) neutralizing units per mouse was determined independently of the mechanism(s) by which monoclonal antibodies mediated the neutralization of the infectivity. On the HN glycoprotein of Sendai (6/94) virus we could not individualize a critical site for successful immune recognition by antibodies although the characteristics of an "ideal protective monoclonal antibody" have also been defined.

A simplified and rapid micromethod based on restriction endonuclease analysis of radiolabelled varicella-zoster virus (VZV) DNA is described and applied to strains for comparison. This procedure is cheaper and less time consuming than that requiring viral nucleocapsid purification (macromethod). The micromethod is suitable for routine DNA analysis of VZV isolates, allows differentiation of vaccine strain from wild strains, and provides evidence for variability of wild strains.

Enteroviruses were specifically detected in crude clinical specimens or in cell cultures in which the viruses were amplified by dot hybridization by using poliovirus type 1-derived, subgenomic radiolabeled cRNA probes (riboprobes). The sensitivity of this test varied from 2.5 to 33%, when clinical specimens without cell culture were examined, and was about 85% in cell culture lysates. The specificity of the test was 90 to 100%. The riboprobe corresponding to the 5'-noncoding sequence specifically detected the majority of enteroviruses (56 of 57 tested); the riboprobe derived from the VPI capsid region hybridized with the three poliovirus serotypes and with some coxsackieviruses type A and with echovirus type 7. Echovirus 22 did not hybridize with any riboprobe. In stool specimens, nasal aspirates, and cerebrospinal fluids from patients with meningitis, only one type of virus was identified in different clinical samples from the same patient by the seroneutralization test. Hybridization allowed the detection of enteroviral RNAs easily in stool specimens and nasal aspirates but with a low efficiency in cerebrospinal fluids without amplification of the viruses in cell cultures.

Adaptation of MDCK cells to serum-free conditions was performed using UltraMDCK medium (BioWHITTAKER).

Herpes simplex virus (HSV) infections are very common in the general population and among immunocompromised patients. Acyclovir (ACV) is an effective treatment which is widely used. We deemed it essential to conduct a wide and coordinated survey of the emergence of ACV-resistant HSV strains . We have formed a network of 15 virology laboratories which have isolated and identified, between May 1999 and April 2002, HSV type 1 (HSV-1) and HSV-2 strains among hospitalized subjects. The sensitivity of each isolate to ACV was evaluated by a colorimetric test (C. Danve, F. Morfin, D. Thouvenot, and M. Aymard, J. Virol. Methods 105:207-217, 2002). During this study, 3,900 isolated strains among 3,357 patients were collected; 55% of the patients were immunocompetent. Only six immunocompetent patients excreted ACV-resistant HSV strains (0.32%), including one female patient not treated with ACV who was infected primary by an ACV-resistant strain. Among the 54 immunocompromised patients from whom ACV-resistant HSV strains were isolated (3.5%), the bone marrow transplantation patients showed the highest prevalence of resistance (10.9%), whereas among patients infected by human immunodeficiency virus, the prevalence was 4.2%. In 38% of the cases, the patients who excreted the ACV-resistant strains were treated with foscarnet (PFA), and 61% of them developed resistance to PFA. The collection of a large number of isolates enabled an evaluation of the prevalence of resistance of HSV strains to antiviral drugs to be made. This prevalence has remained stable over the last 10 years, as much among immunocompetent patients as among immunocompromised patients.

Three subtypes of influenza A viruses, H1N1, H1N2 and H3N2, co-evolve in pigs in Europe. H1N2 viruses isolated from pigs in France and Italy since 1997 were closely related to the H1N2 viruses which emerged in the UK in 1994. In particular, the close relationship of the neuraminidases (NAs) of these viruses to the NA of a previous UK H3N2 swine virus indicated that they had not acquired the NA from H3N2 swine viruses circulating in continental Europe. Moreover, antigenic and genetic heterogeneity among the H1N2 viruses appeared to be due in part to multiple introductions of viruses from the UK. On the other hand, comparisons of internal gene sequences indicated genetic exchange between the H1N2 viruses and co-circulating H1N1 and/or H3N2 subtypes. Most genes of the earlier (1997–1998) H1N2 isolates were more closely related to those of a contemporary French H1N1 isolate, whereas the genes of later (1999–2000) isolates, including the HAs of some H1N2 viruses, were closely related to those of a distinct H1N1 antigenic variant which emerged in France in 1999. In contrast, an H3N2 virus isolated in France in 1999 was closely related antigenically and genetically to contemporary human A/Sydney/5/97-like viruses. These studies reveal interesting parallels between genetic and antigenic drift of H1N1 viruses in pig and human populations, and provide further examples of the contribution of genetic reassortment to the antigenic and genetic diversity of swine influenza viruses and the importance of the complement of internal genes in the evolution of epizootic strains.

Summary. "Sapporo-like viruses" (SLVs) and "Norwalk-like viruses" (NLVs) are an important cause of acute gastroenteritis in humans. While NLVs have been genetically classified into three major genetic groups consisting of 17 genetic subgroups, a classification of SLVs into comparable genetic groups remains to be determined. In an attempt to classify both SLVs and NLVs uniformly, the sequences of 2 SLV strains newly detected from French infants were analysed together with the published sequences of 9 SLV and 19 NLV strains. Distance and phylogenetic analyses were conducted on the sequences of the capsid gene, RNA polymerase gene, 3' open reading frame (3'ORF), ORF overlapping the capsid gene, and 3' untranslated region (3'UTR). The histogram showing frequency distribution of pairwise distances and the topology of the phylogenetic tree demonstrated that SLVs and NLVs could be classified uniformly on the basis of the entire capsid sequences and that the 11 SLV strains could be genetically classified into 3 major genetic groups, genogroups I, II and III, comprised of 5 genetic subgroups. The differentiation of the 11 SLV strains into these genetic groups was also maintained in the 4 remaining genome regions, while the sequences at the junction between the RNA polymerase and capsid genes were shown to be genogroup-specific.

Objective: To investigate the possible association of persistent enterovirus (EV) infection with the development of ALS. Background: Although ALS is a clinically well-defined motor neuron disease, little is known about the etiology and pathogenesis of the sporadic cases. Among the different causes that have been hypothesized, conflicting results have been reported about the possible role of persistent enteroviral infection. Methods: Reverse transcriptase-PCR (RT-PCR) and direct RT in situ PCR (RT-IS-PCR) were performed in formaldehyde-fixed spinal cord samples of 17 patients with confirmed ALS and 29 control subjects with no history of motor neuron disease. When obtained, PCR products were sequenced subsequently. Results: Using direct RT-IS-PCR, EV nucleic acid sequences were detected in 15 (88.3%) of 17 patients with ALS compared to 1 (3.4%) of 29 control subjects. PCR products were located in neuronal cell bodies of the anterior horns of the spinal cord. The RT-PCR products obtained in 13 of the 17 patients with ALS showed between 94% and 86% homology with echovirus 7 sequences. Conclusion: The 88.3% rate of detection of enterovirus (EV) nucleic acids in the neuronal cell bodies within the gray matter of the spinal cord of patients with ALS strongly suggests association between persistent EV RNA and ALS. Further work is required to confirm that the persisting EV sequences we detected are somehow involved in the development of ALS.

International audience; Zur Bewertung der Effizienz eines standardisierten Test-Kits für den Nachweis von Enterovirusgenom in Abwasser wurde in drei Laboratorien eine multizentrische Studie durchgeführt. Einundzwanzig Proben von jeweils 20 Liter Abwasser wurden vor und nach der Konzentration mittels Glaswolle untersucht. Jede Probe wurde sowohl mit Hilfe des Amplicor®-Kits als auch mit in den einzelnen Laboratorien unabhängig entwickelten Methoden untersucht.Nach den Ergebnissen eignet sich das Amplicor®-Kit gut zum Nachweis von Enterovirusgenom in behandeltem Abwasser. Die Ergebnisse sind vergleichbar mit denjenigen, die in den beteiligten Laboratorien mit Hilfe semi-nested RT-PCR erzielt wurden. Allerdings ist die Amplicor®-Kit-Methode einfacher und hat den Vorteil Standard zu sein, was sich für Vergleichsstudien als nützlich erweist.Während der Untersuchung wurde festgestellt, daß sich infektiöse Viren und Virusgenome besser nachweisen lassen, wenn bei der Analyse konzentrierte Proben verwandt werden; A multi-centric study was carried out in three laboratories, to evaluate the efficiency of a standardized kit for the detection of enterovirus genome in wastewater. Twenty one samples of 20 liters of wastewater were analyzed before and after concentration through glass wool. Each sample was analyzed with the Amplicor® kit as well as with techniques developed independently in each laboratory.The results show that the Amplicor® kit is well suited to the detection of enterovirus genome in treated wastewater. The results may be compared to those obtained with semi-nested RT-PCR techniques used in each laboratory. However, the Amplicor® kit technique is more simple and has the advantage of providing a standardized technique useful for comparative studies.During this work it was observed that the sensitivity of the detection of infectious viruses and virus genome was improved when concentrated samples were used for analysis.

A protocol for the in situ polymerase chain reaction (IS-PCR) detection of viral nucleic acid in the heart tissue of four-to-five-week-old CD1 mice infected with coxsackievirus B3 (CBV3) Nancy strain is described. To compare the effects of formalin concentration on the IS-PCR process, two different concentrations (10 and 37%) were employed. Using 37% formalin, 25 PCR cycles were sufficient and a permeabilization step could be omitted. However, postfixation of tissues with 4% paraformaldehyde and 100% ethanol after the deparaffinization, reverse transcriptase and amplification steps was required in order to minimize artefacts. When the tissues were fixed in 10% formalin, postfixation with 4% paraformaldehyde was not required, but a permeabilization step had to be employed and 40 cycles of PCR amplification were needed. To detect the PCR product in the 10% formalin-fixed samples, incubation with 0.3 U/ml of an anti-digoxigenin antibody conjugated to alkaline phosphatase was performed for 90 min. When 37% formalin-fixed samples were used, the concentration of the antibody conjugate had to be increased to 3 U/ml and the exposure time was decreased to 30 min. Enterovirus (EV) nucleic acid was detected in the cytoplasm of myocytes. Thus, IS-PCR was successful in localizing EV nucleic acid in the cytoplasm of myocytes in mice infected with a cardiotropic strain of CBV3. Using this technique, 10% formalin-fixed tissues gave better results than 37% formalin-fixed tissues.

As far as digestive adenocarcinoma are concerned, only surgical exeresis means curative treatment: for digestive unresectable adenocarcinoma, prognosis remains poor and 5 year survival rate are from 0 to 5% (1). Interesting results have been achieved throught immunotherapy but systemic use of immune drugs is limited by severe toxicity (2). To avoid toxicity of systemic immunotherapy, the idea of a local immunotherapy through gene transfer has been designed.

Using different strategies, three mouse hybridoma lines (IgGl, IgG2a, IgM), were adapted to grow in three different serum-free media (BioWHITTAKER): UltraCULTURETM, U1traDOMATM and UltraDOMA-PFTM. According to the characteristics of clones, adaptation to UltraDOMATM and UltraDOMA-PFTM started from UltraCULTURETM and/or FBS-DMEM grown cells. Cell growth, antibody producing activity on a per cell basis and karyological analysis were regularly checked all along the adaptation procedure and over a several month period after transferring cells to serum-free conditions. Results are discussed with respect to the cell line, the cell generation number and the definition of the cell culture environment.

Samples collected in 1987 and 1988 in Brittany from influenza-infected swine made it possible to isolate and antigenically characterize two H1N2 recombinant viruses (Sw/France/5027/87 and Sw/France/5550/88). The former virus was cloned and reinoculated to swine to allow reproduction of the disease and reisolation of a strain similar to the original one. The serodiagnostic tests carried out on both the original sera and those from the experimentally infected animals confirmed that the virus was actually type Sw/H1N2.

HPV infections are induced by a wide range of HPV types affecting squamous stratified epithelia. The possible role of HPV types and the prevalence of antibodies to early HPV oncoproteins may be of major importance as markers for invasive cancer. However, antibody response to HPV is still poorly documented. Recently, seroepidemiologic studies have reported the incidence of antibodies against HPV 16 E4 and E7 proteins in healthy control population and in patients with cervical. cancer, using either fusion protein or synthetic peptides as antigens and a solid phase enzyme linked immunosorbent assay (ELISA) or Western blot (Jochmus-Kudielka et al, 1989, 1992, Mann et al, 1990, Reeves et al, 1990, Jenison et al, 1990, 1991 Muller et al, 1990, 1992, Krchnak et al, 1990, Kochel et al, 1991, Suchankova et al, 1991, 1992, Kanda et al, 1992, Gallaway, 1992).The aim of our study was to detect and quantitate anti-HPV 16 E7 IgG in sera of patients with HPV-induced lesions using an ELISA test developed with a peptide chosen in E7 region (aa 41-aa 60), which cross reacts with HPV types 6 and 18 (Krchnak et al, 1990,) in order to determine the incidence of these antibodies in natural. infection of the normal. population and immunosuppressed patients as compared to women with genital. lesions.

SUMMARY Using both serum-supplemented DMEM and serum-free UltraCULTURE” media (BioWHITTAKER), we have shown that the unstability of mouse hybridomas was dependent 1) on the clonal line, 2) on the culture medium. Employing UltraCULTURE” medium during long-term cultivation of hybridomas, not only prevented the loss of antibody productivity of “unstable clones” but allowed to overcome the degenerating phenomenon initiated by previous cultivation of cells in traditional medium (1). Such a phenomenon was correlated with the selection, in UltraCULTURE” growth conditions, of secreting cells with high chromosome number (> 60 chr.) and increasing chromosomal abnormalities (double-minutes).

Enteroviruses are common pathogens responsible for a wide spectrum of systemic infections. Conventional diagnosis of these infections relies on the isolation of viruses in cell culture and their identification by seroneutralization with polyclonal or monoclonal antibodies. Among enteroviruses, coxsackieviruses B have been involved as causative agents for viral myocarditis. Most of the time, in the case of cardiac pathologies, viral isolation is negative. Molecular biology techniques appear to be an alternative to conventional diagnosis and could supply evidence for the direct implication of enteroviruses in these severe pathologies. In this paper, we describe a murine experimental model of infection with the presumed highly cardiopathogenic coxsackie-virus B type 3. A kinetics of infection was observed for a period of 31 days, and the classical virological markers (viral isolation from feces and heart biopsies, seroconversion) were monitored and compared by means of molecular techniques (molecular hybridization, polymerase chain reaction [PCR]). In this 31-day period, the detection of coxsackievirus B type 3 RNA in the heart was possible only by using two successive seminested PCRs. After 9 to 11 days of active viral replication, when all other virological markers were negative, positive PCR signals were obtained, which supports the hypothesis of a shift to persistent enteroviral infection.

The Directigen Flu-A is an enzyme immunoassay for detecting in 15 min the influenza A nucleoproteinic antigen directly from specimens after passive adsorption on a cellulose membrane. The test was assessed using 160 frozen (−20°C) specimens collected during the 1988–1989 A/H1N1 influenza epidemic and the 1989–1990 A/H3N2 epidemic. Compared to the ELISA immunocapture test, the sensitivity of the commercial test was 87.8% and the specificity was 97.6%. When compared to isolation of viruses on LLCMK2 cells and/or chicken embryo, the sensitivity was 84%. No cross-reaction was found with other respiratory disease viruses. The feasibility, practicability and rapidity of the test make it a test of choice for rapid diagnosis of influenza A.

For the past 2 years, a survey network was established for the screening of acyclovir (ACV)-resistant clinical isolates of herpes simplex virus (HSV). Among 889 strains tested for in vitro ACV sensitivity, 14 HSV-1 and 6 HSV-2 were resistant to ACV concentrations exceeding 3 micrograms/ml. These resistant isolates were most often obtained after prolonged ACV treatment of severely immunocompromised patients. For five patients, the emergence of ACV-resistant virus correlated with treatment failure. In particular, a decrease in the in vitro sensitivity to ACV was observed for eight successive HSV-1 isolates from one immunodeficient patient undergoing therapy. All ACV-resistant isolates were studied for their sensitivity to different antiherpetic compounds and showed various cross-sensitive and -resistant patterns. The examination of viral populations by plaque autoradiography procedures frequently revealed their heterogeneity in terms of thymidine kinase (TK) phenotype and allowed the detection of various proportions of TK-positive (TK+), TK-deficient (TKD), or TK-altered (TKA) viruses. Our data underline the importance of monitoring the emergence of drug-resistant virus during the course of antiviral therapy, and the need for the detection and characterization of TK mutants in clinical specimens. The routine examination of drug sensitivity of HSV isolates provides useful information to clinicians for the management of ACV treatment in the hope of preventing ACV-resistant mutants from becoming predominant in mixed viral populations.

The aim of the study was to evaluate the virological parameters associated with the severity of cytomegalovirus (CMV) disease in renal and simultaneous renal and pancreatic transplantation. The association of the viral profile and the severity of the viral disease was analysed taking into account different confounding variables susceptible to linkage with the severity of the CMV infection and the viral parameters. All the patients transplanted between 1 January 1989 and 31 December 1990, a total of 242, were prospectively followed by viral cultures in blood and urine and by serological methods using the detection of CMV-specific IgM and the complement fixation (CF) test. The samples were taken systematically each week for the first month and then at day 90, 180 and every 6 months and also in cases of clinical manifestations related to viral disease. CMV infection was diagnosed virologically by the presence of viraemia, viruria, IgM, or a significant rise in CMV antibody titre in CF. CMV disease was classified as asymptomatic, mild (fever and/or leukopenia), moderate (fever, leukopenia and liver abnormalities), severe (CMV pneumopathy and/or gastrointestinal disease) or fatal. The incidence of CMV infection was 65% (157/242): 32% asymptomatic, 36% mild, 30% moderate and 2% severe. The presence of IgM was associated with the severity of CMV disease: 51.4% of moderate and severe CMV infections in the group with IgM versus only 16% in the group without IgM (P < 0.0001). The risk of having severe or moderate CMV disease was 3.28 times higher in patients with positive IgM. However the serological changes in CF were not significantly associated with the severity of the viral disease since 34.6% of the patients with CF changes had a severe form versus 20.8% in the group without CF modification. Viruria was significantly associated with moderate or severe infection: 43.6% of the patients with viruria had severe infection versus only 12.5% in the patients without viruria (P < 0.0002). The risk of having moderate or severe CMV disease was 3.48 times higher in the patients with viruria. Viraemia was also associated with more severe CMV infection: 48.6% of moderate or severe CMV infection in the group of patients with viraemia versus 19% in the group without viraemia (P < 0.0001). The risk of having severe or moderate CMV infection was 2.58 times higher in the patients with viraemia. Viraemia was not more associated with severe CMV infection than viruria. Using the maximum likelihood ratio method and the logistic regression model, CMV-specific IgM, viruria and viraemia were each shown to be associated with the severity of CMV disease and the addition of one parameter to the other(s), whatever the type (except the CF changes) and whatever the order of this addition, did not remove the link between the severity and IgM, viruria and viremia. The incidence of severe and moderate CMV disease increased with the number of positive viral parameters (PVP) from 2% of moderate and severe infections in the group with one PVP, to 28% in the group with two PVP, to 39% in the group with three PVP and 68% in the group with four PVP (trend, 35.95; P < 0.0001). Taking the absolute risk of the group of patients without IgM, viruria or viraemia as the basal level, the observed relative risk of severe CMV infection varied from 6.45 in the group with positive IgM without viruria or viraemia, to 10.74 in the group with positive IgM and viruria without viraemia and to 22.5 in the group with the three positive parameters IgM, viruria and viraemia. The different potential confounding factors (recipient and donor serology, renal or renal and pancreatic transplantation, DR compatibility, rejection before CMV infection) did not modify the link between the viral profile and the severity of CMV disease. This study suggests that the severity of CMV disease might be linked to the overspread of the virus as well as to the consequences of a CMV-specific humoral immune response.

In organ transplantation, virus transmitted by the donor is associated with a higher risk of severe primary infection after transplantation in the seronegative recipient. In this study, the risk of hepatitis-C virus (HCV) transmission by the kidney was determined, and the morbidity in the recipient assessed. Serum samples from all kidney donors of our Transplantation Unit between 1983 and 1988 were screened for antibodies to anti-HCV by first enzyme-linked immunosorbent assay (Ortho ELISA) and positive samples were confirmed by a second-generation ELISA and the CHIRON RIBA HCV test. Of the 164 kidney donors whose sera were available, five were positive (3%) and all of them were positive with the RIBA test. Liver function was normal in the five donors. Seven recipients received a renal transplant from the anti-HCV-positive donors. Two patients had a follow-up too short to draw any conclusions. Two patients remained anti-HCV-negative up to 36 and 48 months, respectively, but one of them had chronic hepatitis. One patient was anti-HCV-positive before transplantation and remained positive over the 4-year follow-up. The two last patients seroconverted and acute hepatitis occurred at 16 and 101 days after transplantation, respectively. In both cases, no peroperative or postoperative transfusion was given and no other cause of hepatitis could be determined. A cirrhotic evolution was observed within 15 and 36 months in both cases. Thus HCV can be transmitted by a kidney transplant and cadaveric donors positive for anti-HCV antibodies should be excluded from kidney donation.

Epidemiological studies were carried out in Yaounde and in Ngaoundere from 1984 to 1986, in an attempt to develop adequate methods of collecting blood from small children and of diagnosing measles appropriate to conditions in the field. Alternative methods were necessary since classical methods used in modern laboratories are unsuitable in rural regions. Each study was carried out on a representative sample of 6- to 36-months-old infected children seen at consultation. This group was chosen because it suffers the highest mortality rate. The blood was obtained by digital puncture on blotting paper because venepuncture required sterile equipment and also the establishment of a cold chain for transporting the samples to the laboratory. The first criteria examined were the relative titers of sera taken by finger prick. Four serological techniques were used: indirect immunofluorescence (IIF), indirect immunoperoxidase (IIP), hemagglutination inhibition (HAI) and ELISA. Antimeasles antibodies were detected in 12% of infected children using IIF and in 18% using IIP. When sera were examined by HAI the percentage of positives was 54% and by ELISA 75%. These results clearly indicate that ELISA is the most effective and practical technique for diagnosing measles under field conditions.

Clinical isolates of influenza A viruses identified during outbreaks in two winters were tested for their rimantadine susceptibilities by an enzyme-linked immunosorbent assay modified from that described previously by Belshe et al. (R. B. Belshe, B. Burk, F. Newman, R. L. Cerruti, and I. S. Sim, J. Virol. 62:1508-1512, 1988). The infectivity titer and the 50% inhibitory concentration of rimantadine were calculated for each virus. Of 105 influenza virus A isolates tested, 28 influenza A/H1N1 isolates from the 1988 and 1989 outbreak and 77 influenza A/H3N2 isolates from the outbreak in following year, were susceptible to the antiviral action of rimantadine.

Resume L'enquete serologique (tests HR et IH) porte sur un echantillonnage representatif de la production porcine en Bretagne. L'infection grippale qui n'avait atteint que le tiers des elevages en 1977 diffuse dans 80% des elevages en 1978 et 60% en 1979: le pourcentage d'infectes dans l'effectif controle est passe de 13,5 a 50% puis 36,5%. L'etude de l'infection grippale en fonction du rang de portee et de la specificite des anticorps detectes montre que: —Des virus apparentes a A/PC avaient circule avant 1975. —Des virus apparentes a A/PC/73 et A/VIC/75 ont diffuse dans l'hiver 1975–1976; puis dans l'hiver 1977–1978 apparaissent des infections par des virus portant des antigenes HA apparentes a A/Tex/77. —On trouve, des mai 1978, quelques animaux portant des anticorps anti H1N1. Il n'est detecte aucun anticorps vis-a-vis des souches porcines apparentees a A/Swine/31 et 61. Pour A/NJ/76 des anticorps sont detectes par hemolyse radiale dans 7/25 elevages a partir de mai 1978.

Resume Une epidemie de grippe equine est survenue en France en Automne 1978 et s'est etendue progressivement a l'ensemble du territoire au cours du premier semestre 1979. Elle correspond a la reapparition du virus influenza A equi 2 alors que depuis 1973 il n'y avait que des foyers isoles dus au virus A equi 1. Ce virus A equi 2 n'est pas un variant de la souche A equi 2 Miami 63 et des souches A equi 2 isolees anterieurement en France. La vaccination s'est montree souvent incapable de proteger les chevaux contre cette infection.

A technique for quantitativly evaluating flue antibodies using the passive Hemolysis of sheep red blood cells sensitized by influenza virus is described (Single Radial Hemolysis in agar medium). Compared with Hemagglutination inhibition, this test appears to be equally specific and at the same time better suited for measurement of small amounts of antibodies, in the horse. The test has been used to determine serodiagnosis after infection as well as post-vaccinal immune reactions., Une technique d’évaluation quantitative des anticorps grippaux basée sur l'hémolyse passive d'hématies de mouton sensibilisées par le virus grippal est décrite (hémolyse radiale en milieu gélosé). Comparé à l'inhibition de l’hémagglutination le test paraît également spécifique mais plus apte à apprécier les faibles taux d’anticorps. Il a été utilisé pour déterminer les séro-conversions chez les chevaux convalescents et les réactions immunitaires post-vaccinales., Fontaine M.-P., Fontaine M., Aymard M., Nafti K. Technique d’hémolyse radiale pour la mesure des anticorps anti-influenza chez le cheval. In: Bulletin de l'Académie Vétérinaire de France tome 134 n°1, 1981. pp. 105-112.

Resume Les infections ORL virales de l'enfant sont frequentes. De larges enquetes epidemiologiques ont montre que certains virus avaient un tropisme preferentiel ; les Rhinovirus sont les principaux responsables des rhumes et les virus Parainfluenza sont les plus frequents agents des laryngites aigues. Les pharyngites et angines sont plus souvent d'origine virale que bacterienne : les “virus respiratoires” (Influenza A, RSV, ADV, et Parainfluenza) sont responsables d'epidemies de pharyngites et d'otites moyennes. Dans la surdite, les virus ont aussi un role dominant : la surdite neurosensorielle bilaterale provient d'infections congenitales par le virus de la rubeole et le Cytomegalovirus (CMV). Dans la surdite “soudaine”, de nombreux virus ont ete incrimines : ceux des meningites virales, des Oreillons, de la Rubeole, le virus Influenza B, le virus Varicello-zonateux, le CMV et l'EBV. Parmi les manifestations tumorales, le papillome larynge a HPV est rare. Le role etiologique des virus dans les affections ORL a ete argumente sur des donnees epidemiologiques, mais c'est la presence du virus, de ses antigenes dans les cellules des divers organes qui prouve sa multiplication locale et son role pathogene direct.

Summary The frequency and severity of CMV infections in kidney, bone marrow, heart transplant recipients, in polytransfused patients, in immunodeficiencies and in newborns with congenital or peri-natal infection prompted clinical trials of immunoglobulins (Ig) with anti-CMV activity. Among the various methods for titrating Ig of plasmatic or placental origin, polyvalent or hyperimmune, ELISA would be the most sensitive assay and the neutralizing reaction might be the better reflection of a protective effect. In kidney transplantation, two non-randomized clinical trials have suggested a curative effect in association to other treatments, especially when given early. In bone marrow transplantation, three randomized studies have shown a prophylactic effect on incidence of symptomatic infections, interstitial pneumonias due to CMV, but only in seronegative patients not treated with leucocyte transfusions. No effect was observed on the time of infection, the survival of patients, the incidence of surinfections or graft versus host disease. The prophylactic effect of anti-CMV Ig in kidney and heart transplantation as well as in newborns has still to be documented in randomized trials. The possible clinical benefit for the patients and the mode of preparation of effective anti-CMV antibodies need further investigations.

A rapid and sensitive colorimetric assay has been developed to evaluate the sensitivity of herpes simplex viruses (HSV) to antiviral agents. The chessboard titration of viruses and antiviral drugs and the automatic reading and analysis of the data allows objective and accurate results to be rapidly obtained. Virus sensitivity was expressed as an ED50 value which was the concentration of drug (micrograms/ml) reducing viral cpe by 50%. The ED50 values of antiviral drugs [acetylguanosine (ACV), idoxuridine (IDU), deoxycytidine (IDC) and bromovinyl deoxyuridine] for several HSV reference strains were determined and the method was then applied to clinical specimens. The selection of ACV and IDU resistant mutants was performed on a cloned sensitive HSV 1 ocular strain. We observed cross-resistance between ACV and IDU for the mutants isolated. The resistance to thymidine-kinase-dependent antiviral agents varied in inverse ratio to the thymidine kinase activity induced by HSV strains.

The Blood Transfusion Centers (B.T.C.) are mainly concerned with the selection of CMV infection free blood donors, the screening of the anti CMV antibody high titre plasma donors and the evaluation of specific anti CMV Immunoglobulin preparations. Various serological methods could be used but they are of different value depending the purposes of the B.T.C. The neutralization test (Nt), with the addition of complement is specific and detects the protecting AB against the glycoproteins of the viral envelope. The complement fixation test (CF) using extracts of CMV infected cells as antigen largely varies in its sensitivity according to the quality of the antigen. In any case, the CF test is not sensitive enough to detect a latent CMV infection in a certain percentage of the non immunosuppressed adults, but could be used for the selection of anti CMV antibody high titres carriers. Three sensitive methods: passive haemagglutination, indirect immunofluorescence and indirect ELISA tests, might be used for the detection of latent CMV infections. They detect various AB against various internal and external components of the CMV. They are submitted to various sources of errors. The sensitivity of the indirect IF test is mainly restricted by the quality of the antigen preparation, its specificity by the presence of anti cells antibodies in the sera, the Fc receptors in the antigens and the specificity of the conjugates. The indirect ELISA which is submitted to the same causes of errors is a highly sensitive test, easy to perform, reagents are available, and automatic processors have been developed. When compared with the previous techniques, the ELISA test is suitable for the screening of CMV free donors, when it is performed with an highly sensitive antigen. It could be also used for the screening of high antibody titre carriers: its correlation with the CF test is quite good (r = 0,82). When comparatively applied to the titration of Immunoglobulins preparations, made from plasmas or placentas, for either IM or IV administration, the Elisa test gives AB titres different from those obtained with Nt and indirect IF. The calibration of a standard Immunoglobulin reagent is urgently needed and double blind clinical assays of the protective effect of various preparations of specific anti CMV Immunoglobulins have to be promptly designed.

A simple, indirect enzyme immunoassay using purified enterovirus adsorbed on to nitrocellulose has been developed for screening monoclonal antibodies to enteroviruses. The sensitivity of the assay ranged from 10 ng to 1 μg of viral protein and was 10- to 50-fold more sensitive than conventional EIA on microplates. This simple, sensitive and specific assay proved to be a useful and practical tool for detecting monoclonal antibodies which would not be found in a conventional EIA screening procedure.

Summary Different strains of influenza virus H3N2 and H1N1 (Swine) were isolated from foetuses and stillbirths of naturally infected sows during 1981–83 and 1984 outbreaks in Brittany. The significance of these isolates is discussed.

In order to improve the knowledge of the humoral immune response to CMV infection, we developed an immunoblotting technique which allowed a better analysis of the changes in the pattern of anti CMV-polypeptides IgM. We examined 234 sera belonging to 27 renal allograft recipients developing a primary or recurrent CMV infection and 12 non infected recipients. Thus we found that 11 main anti CMV-polypeptides IgM antibodies were present in over 25% of the infected patients. They reacted with proteins whose molecular weights ranged from 32K to 205K. We showed that anti-p 45-47 IgM antibodies were present in 100% of CMV infected recipients and never in the non-infected population. They appeared very early in the course of the infection (5.43 weeks post-graft for primary infection and 5.00 weeks for recurrent ones) and, therefore, constitute a good marker of active infection. Two other CMV-specific IgM antibodies (anti-p 60-64 and anti-p 100) were found exclusively in the course of primary infections. Anti-p 60-64 IgM was observed at a high frequency (57.1%) and with a mean delay of 6.57 weeks post-graft. Therefore, the anti-p 60-64 IgM detection could be helpful for the diagnosis of primary infection. In almost 100% of both primary and recurrent infections, we observed anti-p 140 and anti-p 38 IgM antibodies. Only about 50% of non-infected patients had low levels of anti-p 140 and anti-p 38 IgM. The follow-up of recurrent infections showed that the anti CMV-polypeptides IgM antibodies appeared earlier than in primary infection. When we compared anti-p 45-47 IgM detection by immunoblotting and anti-CMV IgM detected by ELISA we observed that immunoblotting permitted the diagnosis 2.5 weeks earlier for primary infection, and 1 week earlier for recurrent infection, than ELISA. In addition, the detection of anti-p 45-47 IgM antibodies also occurred earlier than virus excretion.

Resume En utilisant la methode de l'hemolyse radiale, on a observe que chez les porcs ont diffuse jusqu'en 1979 a la fois des souches apparentees a A/Port-Chalmers/73 et A/Victoria/75. Les anticorps anti A/Texas/77 sont apparus chez les porcs en meme temps que chez les humains (avril 1978). On n'a detecte d'infection a souches apparentees a A/Swine ni chez l'homme, ni chez les porcs. Des anticorps anti A/H1N1 et A/New Jersey/76 ont ete detectes essentiellement chez les animaux ayant deja des anticorps anti A/Port Chalmers/73 et/ou A/Victoria/75 et/ou A/Texas/77. Il existe une correlation pour la frequence et la specificite des anticorps anti influenza A entre les porcs et les eleveurs. Le renouvellement rapide des porcs dans les elevages permet la persistance des souches d'influenza A dans ce reservoir et des echanges reciproques avec le reservoir humain qui se traduit par un profil immunitaire antigrippal des eleveurs significativement different de celui des autres groupes humains apparies, etudies.

A study is carried on in a group of 16 commercial breeding-finishing units in Brittany (France). The aim of this study is to try to reveal the persistence of activity of the Influenza Virus within these intensive units after an acute epizootic. In each farm two batches of pigs are selected, individually identified and followed from suckling period to slaughter. Serological controls are conducted every month on the same pigs. Both Influenza and Aujeszky's disease antibodies are apprehended. Furthermore nasal swabs and lungs are submitted to analysis for virus isolation purposes and data are collected from each herd for epidemiological studies. Influenza passive H.I. Antibodies rapidly decrease in the piglets. Later a seroconversion is observed in 10% of the investigated piglets. These pigs belong to 4 herds. The conversion happens usually after 3 months of age. All attempts to isolate the virus failed. Special herd conditions may be associated with a persistence of the viral activity inside the units between epizootics: bad demography (unbalance in the breeding stock), inadequate hygiene policy in the fattening house (with permanent arrivals of pigs coming from subsequent batches of sows), a high prevalence of respiratory and specially pulmonary enzootic diseases. A seroconversion against Aujeszky's disease is pointed out in 3 out of the 4 herds concerned with Influenza virus activity suggesting that closely the same conditions may be related both to influenza and Aujeszky's disease virus activity.

The thermal stability and the effect of guanidine on the hemagglutinin and neuraminidase of three strains of mumps virus were compared. The heat inactivation of hemagglutinin resulted in the concomitant loss of neuraminidase. The effect of guanidine at various molarities showed that the neuraminidase was more sensitive than the hemagglutinin and a selective inactivation was obtained after exposure to 1.5 M guanidine. However differences in sensitivity of both activities (hemagglutinin and neuraminidase) to heat and guanidine inactivations were observed among strains and correlated with differential susceptibility to non-specific inhibitors of the strains.

59 sera of 10 immunosuppressed renal allograft recipients who experienced recurrent cytomegalovirus (CMV) infection were analyzed by enzyme-linked immunosorbent assay (ELISA) for CMV IgA antibodies and by the complement-fixation (CF) test. A significant rise of CF titer was evident 4-53 weeks post-transplantation. 9 patients produced CMV IgA in high titers at about the time of CF antibody rise was observed. 1 patient did not produce IgA antibodies to CMV. In 3 of the 9 patients, specific CMV IgA antibodies were detected before the rise if CF titer was demonstrated. CMV IgA antibodies were found to persist for as long as 6 weeks post-transplantation. The potential application of ELISA detection of CMV-specific IgA antibodies as an early indication of CMV infection in kidney transplant patients is discussed.