http://repub.eur.nl/res/aut/459/ List of Publications en http://repub.eur.nl/static-eur/img/logo.png http://repub.eur.nl http://repub.eur.nl/res/pub/3563/ 1996-01-01T00:00:00Z To study the relationships between herpesvirus recently isolated from different pinniped species, antigenic and genetic analyses were performed. First, herpesviruses isolated from North American harbour seals (Phoca vitulina), a Californian sea lion (Zalophus californianus) and a European grey seal (Halichoerus grypus) were examined in an enzyme immunoassay (EIA) with a panel of monoclonal antibodies which had previously been shown to allow typing of herpesviruses from European harbour seals into two distinct virus types: phocid herpesvirus type-1 and type-2 (PhHV-1 and PhHV-2). The EIA data showed that all but one of the isolates from seals ranging in United States coastal waters were PhHV-2-like while the European grey seal herpesvirus was PhHV-1-like. Genetic characterization was facilitated by PCR analysis using primers based on conserved regions of the glycoprotein B and D (gB and gD) genes of the antigenically closely related canid (CHV) and felid (FHV) herpesvirus. Specific amplified products were obtained with five isolates antigenically characterized as PhHV-1-like but not with five PhHV-2-like isolates. Sequence analysis of the PCR products confirmed greatest similarity to members of the genus Varicellovirus of the Alphaherpesvirinae and in particular to CHV. Sequence analysis of two EcoRI fragments of the PhHV-2 genome (European isolate 7848) revealed greatest similarity to gammaherpesviruses and in particular equine herpesvirus-2. Although an unambiguous subgrouping was not feasible, this is the first evidence that PhHV-2 may be a putative gammaherpesvirus of pinnipeds. http://repub.eur.nl/res/pub/3531/ 1995-01-01T00:00:00Z Sequence analysis of the haemagglutinin protein (H) gene of the morbillivirus (PDV-2) isolated from a Siberian seal (Phoca sibirica) during the 1987/1988 epizootic in Lake Baikal revealed that it was most closely related to two recent isolates of canine distemper virus (CDV) from Germany and different from CDV vaccines currently in use in that region. The virus continued to circulate in seals in Lake Baikal after the 1987/1988 epizootic since sera collected from culled seals in the spring of 1992 were positive in morbillivirus ELISA tests, reacting most strongly with the CDV antigen. http://repub.eur.nl/res/pub/3501/ 1994-01-01T00:00:00Z Murine monoclonal antibodies (MAbs) were generated against phocid herpesviruses (PhHV 2557/Han88 and 7848/Han90) isolated from European harbour seals (Phoca vitulina), and against strains of both felid (FHV strain FVR 605) and canid herpesviruses (CHV isolate 5105/Han89). MAbs were characterized with respect to certain biological properties and used to outline antigenicity profiles of isolates of PhHV (n = 8), FHV (n = 7) and CHV (n = 3) in enzyme immunoassays employing fixed infected cells. A close antigenic relationship between herpesviruses derived from pinnipeds and terrestrial carnivores became evident: The majority of the MAbs was directed against epitopes which were expressed by at least two of the viral species tested. A number of MAbs detected epitopes which were conserved between all isolates of PhHV, FHV and CHV. A few MAbs recognized type-specific B-cell epitopes and facilitated the identification of single viral species. Moreover, the PhHV isolate 7848/Han90 was antigenically distinguishable both from seven other phocid herpesvirus isolates and from FHV or CHV. PhHV 7848/Han90 proved to be antigenically distinct from all other viruses tested when examined by cross neutralization utilizing various reconvalescent and hyperimmune sera. Although more data are needed to ensure that PhHV 7848/Han90 indeed is a new genuine seal herpesvirus, the preliminary clustering of two groups of phocid herpesvirus isolates, tentatively designated PhHV-1 (type isolate 2557/Han88) and PhHV-2 (represented by 7848/Han90), seems to be justified. By using selected MAbs an unambiguous identification and typing of herpesvirus isolates derived from marine mammals and terrestrial carnivores is significantly facilitated.