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R E Marschang

Publications and source records attributed to R E Marschang.

8 recordsLinked to original sources

Comparison of 16 chelonid herpesviruses by virus neutralization tests and restriction endonuclease digestion of viral DNA.

A total of 16 chelonid herpesviruses that were isolated between 1992 and 1998 were compared with one another on the basis of serology and restriction enzyme digestion patterns of viral DNA. The viruses stem from tortoises of three different species in four different European countries and the United States of America. The majority of the isolates were similar to one another. One isolate, however, differed strongly from all others both serologically and in the restriction cleavage pattern of its DNA, showing that there are at least two different sero- and genotypes of herpesviruscs that infect tortoises.

Animals↗

Enzyme-linked immunosorbent assay for detecting herpesvirus exposure in Mediterranean tortoises (spur-thighed tortoise [Testudo graeca] and Hermann's tortoise [Testudo hermanni]).

An enzyme-linked immunosorbent assay (ELISA) was developed for the detection of antibodies to a herpesvirus associated with an upper respiratory tract disease in Mediterranean tortoises [spur-thighed tortoise (Testudo graeca) and Hermann's tortoise (Testudo hermanni)]. This serodiagnostic test was validated through a hyperimmunization study. The mean of the A(405) readings of the plasma samples collected at time zero of the hyperimmunization study plus three times the standard deviation was used as the cutoff for seropositivity in tortoises. ELISA results were compared to serum neutralization (SN) values for the same samples by using the McNemar test. The results obtained by SN and ELISA were not significantly different (P > 0.05). This new ELISA could be used as an important diagnostic tool for screening wild populations and private and zoo collections of Mediterranean tortoises.

Animals↗

Virus isolation and vaccination of Mediterranean tortoises against a chelonid herpesvirus in a chronically infected population in Italy.

A chelonid herpesvirus was isolated from a group of tortoises in Italy with a history of increased mortality and upper digestive and respiratory tract disease. The isolated virus was inactivated with formalin and used to prepare a nonadjuvanted vaccine and a vaccine adjuvanted with aluminum hydroxide. 57 tortoises, 26 Testudo hermanni, 25 T. graeca, and 6 T. marginata, were included in the study. The animals were vaccinated 3 times at 45 day intervals. Blood was collected from the animals 14 days prior to the first vaccination, and on day 0, 25, 45, 90, 113 and 369 after the first vaccination. Plasma antibody titers to the homologous chelonid herpesvirus were determined using a virus neutralization test (VNT). No significant rise in antibody titer was noted in the vaccinated animals. Antibody titers measured dropped below the cutoff-level sporadically in all positive animals. Repeat serological testing may therefore be necessary in order to detect seropositive animals.

Adjuvants, Immunologic↗

Detection of chelonid herpesvirus DNA by nonradioactive in situ hybridization in tissues from tortoises suffering from stomatitis-rhinitis complex in Europe and North America.

Chelonid herpesvirus (ChHV) infection in tortoises associated with stomatitis-rhinitis complex is a severe, mostly epizootic disease characterized by proliferative and diphtheroid-necrotizing glossitis, pharyngitis, rhinitis, and tracheitis, often occurring with pneumonia and encephalitis. The UL5 gene from a German ChHV isolate was used to generate a digoxigenin-labeled 307-base-pair DNA probe by polymerase chain reaction (PCR). ChHV DNA was detected in paraffin-embedded tissues of five naturally infected tortoises (two Afghan tortoises [Testudo horsfieldii], USA; two Hermann's tortoises [Testudo hermanni], Switzerland; one T. hermanni, Germany) by means of in situ hybridization (ISH) and PCR. Distribution of ChHV DNA exhibits many characteristics of alphaherpesvirus but also some characteristics of betaherpesvirus infections. The amino acid sequence of a portion of the ChHV UL5 homolog exhibited more than 50% similarity to alphaherpesvirus UL5 proteins. Nuclear hybridization signals were detected in epithelial cells of the lingual mucosa and glands. Furthermore, ChHV DNA was observed in tracheal epithelium, pneumocytes, hepatocytes, the renal tubular epithelium, cerebral glia cells and neurons, and intramural intestinal ganglia. ChHV DNA in endothelial cells of many organs underlines the systemic character of the disease. Importantly, ChHV DNA was detected by ISH in multiple tissues of tortoises originating from different geographic provenances. This indicates a high degree of conservation of the UL5 gene fragment among viruses prevalent in tortoises on different continents. With the described ISH, a molecular biological tool is available for rapid and specific diagnosis of ChHV infections and, more importantly, comparative pathogenetic studies of ChHV isolates from geographically unrelated regions.

Animals↗

Isolation and characterization of an iridovirus from Hermann's tortoises (Testudo hermanni).

A virus was isolated from tissues of 2 diseased Hermann's tortoises (Testudo hermanni) and preliminarily characterized as an iridovirus. This conclusion was based on the presence of inclusion bodies in the cytoplasm of infected cells, sensitivity to chloroform, inhibition of virus replication by 5-iodo-2'-desoxyuridine and the size and icosahedral morphology of viral particles. The virus was able to replicate in several reptilian, avian and mammalian cell lines at 28 degrees C, but not at 37 degrees C. Restriction enzyme analysis showed resistance of the ral DNA to digestion with HpaII due to methylation of the internal cytosine at CCGG sequences. Part of the genomic region encoding the major capsid protein was amplified by PCR and subjected to sequence analysis. Comparative analysis of the obtained nucleotide sequence revealed that the isolate is closely related to frog virus 3, the type species of the genus Ranavirus.

Amino Acid Sequence↗

Paramyxoviral and reoviral infections of iguanas on Honduran Islands.

Thirty-five free-ranging healthy spiny-tailed iguanas (31 Ctenosaura bakeri, 4 C. similis) and 14 green iguanas (Iguana iguana rhinolopha) were caught and held in captivity for 2 days. Blood was collected from all animals and their sera were evaluated for antibody titres against reptilian reoviruses, reptilian paramyxoviruses, and avian paramyxovirus-1 (PMV-1). Cloacal and pharyngeal swabs also were collected and examined for viral content by incubation on chicken embryo fibroblasts (CEF) and terrapene heart cells (TH-1). No virus was isolated from the pharyngeal and cloacal swabs on CEF and TH-1. Twenty-three (47%) of 49 sera samples tested positive for reptilian reoviruses by virus neutralization tests. Twenty (41%) of 49 samples had antibodies against one reptilian PMV isolate by virus neutralization tests and 3 (9%) of 34 by hemagglutination inhibition tests. No antibodies were detected against the other PMV isolate of reptilian origin nor against avian PMV-1. This is the first description of serum antibodies against reptilian reoviruses and PMV in wild iguanas.

Animals↗

Herpesviruses in tortoises: investigations into virus isolation and the treatment of viral stomatitis in Testudo hermanni and T. graeca.

Various studies were done during a spontaneous outbreak of stomatitis-rhinitis-complex (mouth rot) in a collection of Mediterranean land tortoises (21 Testudo hermanni, Hermann's tortoises, and three Testudo graeca, spur-thighed tortoises) in southern Germany. These studies were intended to help diagnose the causative agent, establish a possible diagnostic method in vivo and provide information on the efficacy of aciclovir and ganciclovir against chelonian herpesviruses. Thirteen T. hermanni and no T. graeca died within a period of 6 weeks following the introduction of one apparently healthy T. graeca. Two of the dead Testudo hermanni were submitted for post-mortem examination. In addition, blood samples from 11 of the 12 tortoises still surviving at the beginning of this study were cultured for virus content and for the presence of neutralizing antibodies to chelonian herpesviruses and swabs from conjunctiva, pharynx and cloaca were cultured for the presence of viruses. Herpesviruses were isolated from tissues of the two dead Testudo hermanni (tongue, intestine, trachea, lung, spleen, heart and brain). Peripheral leukocytes from one of 11 blood samples were positive for herpesvirus isolation, indicating viremia in at least one animal. Nine of 11 pharyngeal swabs but none of the conjunctival and cloacal swabs yielded herpesviruses. Circulating neutralizing antibodies were present in two of two tested T. graeca, but absent in all of the nine samples from T. hermanni. Aciclovir and ganciclovir were effective when tested in vitro against one of the herpesvirus isolates.

Acyclovir↗