Blood–retinal barrier breakdown in experimental coronavirus retinopathy: association with viral antigen, inflammation, and VEGF in sensitive and resistant strains

Journal of Neuroimmunology
Volume 119, Issue 2, 1 October 2001, Pages 175-182

Stanley A. Vinores, Yun Wang, Melissa A. Vinores, Nancy L. Derevjanik, Albert Shi, Diane A. Klein, Barbara Detrick, John J. Hooks

Abstract

Intraocular coronavirus inoculation results in a biphasic retinal disease in susceptible mice (BALB/c) characterized by an acute inflammatory response, followed by retinal degeneration associated with autoimmune reactivity. Resistant mice (CD-1), when similarly inoculated, only develop the early phase of the disease. Blood–retinal barrier (BRB) breakdown occurs in the early phase in both strains, coincident with the onset of inflammation. As the inflammation subsides, the extent of retinal vascular leakage is decreased, indicating that BRB breakdown in experimental coronavirus retinopathy (ECOR) is primarily due to inflammation rather than to retinal cell destruction. Vascular endothelial growth factor (VEGF) is upregulated only in susceptible mice during the secondary (retinal degeneration) phase.

Keywords

Coronavirus, Blood–retinal barrier, Vascular endothelial growth factor, Retinopathy

Reduced Macrophage Infiltration and Demyelination in Mice Lacking the Chemokine Receptor CCR5 Following Infection with a Neurotropic Coronavirus

Virology
Volume 288, Issue 1, 15 September 2001, Pages 8-17

William G. Glass, Michael T. Liu, William A. Kuziel, and Thomas E. Lane

Abstract

Studies were performed to investigate the contributions of the CC chemokine receptor CCR5 in host defense and disease development following intracranial infection with mouse hepatitis virus (MHV). T cell recruitment was impaired in MHV-infected CCR5−/− mice at day 7 postinfection (pi), which correlated with increased (P ≤ 0.03) titers within the brain. However, by day 12 pi, T cell infiltration into the CNS of infected CCR5−/− and CCR5+/+ mice was similar and both strains exhibited comparable viral titers, indicating that CCR5 expression is not essential for host defense. Following MHV infection of CCR5+/+ mice, greater than 50% of cells expressing CCR5 antigen were activated macrophage/microglia (determined by F4/80 antigen expression). In addition, infected CCR5−/− mice exhibited reduced (P ≤ 0.02) macrophage (CD45highF4/80+) infiltration, which correlated with a significant reduction (P ≤ 0.001) in the severity of demyelination compared to CCR5+/+ mice. These data indicate that CCR5 contributes to MHV-induced demyelination by allowing macrophages to traffic into the CNS.

Keywords

chemokine, chemokine receptor, demyelination, multiple sclerosis, macrophage, neuroimmunology

Regular Articles Variation of the sequence in the gene encoding for transmembrane protein M of canine coronavirus (CCV)

Molecular and Cellular Probes
Volume 15, Issue 4, August 2001, Pages 229-233

A. Pratelli, V. Martella, G. Elia, N. Decaro, A. Aliberti, D. Buonavoglia, M. Tempesta and C. Buonavoglia

Abstract

A nucleotide variability in the sequence of the gene encoding for the transmembrane protein M of canine coronavirus (CCV) is described. A total of 177 faecal samples from pups with enteritis were analysed by a PCR and n-PCR specific for CCV. Four samples, collected from a dog presenting a long-duration shedding of CCV, and a sample from another diarrhoeic dog, were found positive by PCR but negative by n-PCR. Sequence analysis of the samples revealed silent nucleotide substitutions in the binding site of the internal primer used for the n-PCR. Moreover, the nucleotide substitutions occurring over the whole fragment of the five samples analysed were similar.

Keywords

canine coronavirus, M protein, variation

Comparison of the sialic acid binding activity of transmissible gastroenteritis coronavirus and E. coli K99

Virus Research
Volume 75, Issue 1, May 2001, Pages 69-73

Christel Schwegmann, Gert Zimmer, Teruo Yoshino, Marie-Luise Enss, Georg Herrler

Abstract

Transmissible gastroenteritis coronavirus (TGEV) and Escherichia coli K99 are both enteropathogenic for pigs with infections being most severe in neonate animals. For both microorganisms, a sialic acid binding activity has been shown to be an essential pathogenicity factor. Here we demonstrate with haemagglutination and haemagglutination-inhibition assays that TGEV and E. coli K99 differ in their sialic acid binding activities with respect to the type and amount of sialic acid residues required on the erythrocytes surface as well as with respect to the type of sialoglycoconjugate preferentially recognized. Intestinal mucins from piglets (12–14 days old) and adult animals were shown to inhibit TGEV to the same extent. From our results we conclude that E. coli K99 and TGEV interact with different sialoglycoconjugates to establish an intestinal infection. The implications for the enteropathogenicity of TGEV are discussed.

Keywords

TGEV, E. coli K99, Sialic acid, Mucins, Glycolipids

Orchitis in a Cat Associated with Coronavirus Infection

Journal of Comparative Pathology
Volume 124, Issues 2–3, February 2001, Pages 219-222

O. G. Sigurdardottir, Ø. Kolbjørnsen and H. Lutz

Abstract

A case of severe, pyogranulomatous and necrotizing orchitis in a cat, which later succumbed to systemic feline infectious peritonitis (FIP), is described. The 3·5-year-old cat, positive for feline immunodeficiency virus infection, presented with a left testicular enlargement. A few months after castration the animal was humanely destroyed due to declining health. Post-mortem examination revealed inflammatory lesions in abdominal organs and in the brain compatible with FIP. Infection was confirmed with a reverse transcriptase–polymerase chain reaction test and by immunohistochemical demonstration of coronavirus antigen in the affected tissues, including the left testicle. FIP is usually a systemic disease. However, lesions and presenting clinical signs in a single organ system such as the brain are not uncommon. The results of this case study indicate that orchitis, although rare, should be on the list of lesions of FIP.

Keywords

coronavirus antigen, orchitis, feline infectious peritonitis,