Susceptibility of BALB/c-nu/nu Mice and BALB/c Mice to Equine Herpesvirus 9 Infection. (May 2014)

• Record Type: Journal Article
• Authors: El-Nahass, E.; El-Dakhly, Kh. M.; El-Habashi, N.; Anwar, Sh. I.; Sakai, H.; Hirata, A.; Okada, A.; Abo-Sakaya, R.; Fukushi, H.; Yanai, T.
• Is Part Of: Veterinary pathology. Volume 51:Number 3(2014:May)
• Page Start: 581
• Page End: 590
• Publication Date: 2014-05
• Subjects: Immunodeficiency -- Athymic nude mice -- Equine herpesvirus 9 -- Immunohistochemistry -- Virus infection -- Olfactory bulb -- Brain -- Nasal cavity; Veterinary pathology -- Periodicals; Pathology, Veterinary -- Periodicals; 636.089607
• DOI: 10.1177/0300985813493932
• Languages: English
• ISSNs: 0300-9858

Abstract

This study aimed to clarify the timing and infectivity of equine herpesvirus 9 (EHV-9) infection in BALB/c-nu/nu mice and their immunocompetent counterpart (BALB/c). Following intranasal inoculation with 10 5 PFU of EHV-9, specimens from 8 mice per group were collected at different times postinoculation (PI) and assessed using histopathology, immunohistochemistry for viral antigen, and quantitative real-time polymerase chain reaction for ORF30 gene expression. In BALB/c-nu/nu mice, EHV-9 antigen was abundant in olfactory epithelia of all inoculated animals, and in the olfactory bulb of 1 animal. In contrast, only 1 BALB/c mouse per time point had rhinitis, with mild to moderate immunopositivity starting from 12 to 48 h PI, followed by a gradual virus clearance at 72 h PI. Statistically, significant differences were noted in the immunohistochemistry reactions between the 2 mouse strains, indicating that BALB/c-nu/nu is more susceptible to infection. Relative expression levels of ORF30 gene in olfactory epithelia were significantly different between the 2 groups, with the exception of 12 h PI, when BALB/c-nu/nu animals showed dramatic increases in ORF30 gene expression level until 48 h PI, followed by a decline in expression level until the end of experiment. In contrast, the expression level in brains showed no differences between mouse strain except at 96 h PI. In both strains, the highest messenger RNA expression was detected at 48 h PI, followed by a decline in BALB/c mice, proving a rapid clearance of virus in BALB/c and a gradual slowing down of the increased expression levels in BALB/c-nu/nu.