Development and evaluation of an immunochromatographic strip for rapid detection of porcine hemagglutinating encephalomyelitis virus

Abstract

BackgroundThe incidence of PHE among pigs in many countries is on the rise, and it has caused great economic losses to the pig industry. Therefore, the development of a sensitive, specific, and easily-performed assay is crucial for the rapid detection and surveillance of PHE-CoV infection and transmission.ResultsAn immunochromatographic strip was developed for the detection of PHE-CoV. The colloidal gold-labeled MAb 4D4 was used as the detection reagent, and the MAb 1E2 and goat anti-mouse IgG coated the strip's test and control lines, respectively. The immunochromatographic strip was capable of specifically detecting PHE-CoV with a HA unit of 2 within 10 min. Storage of the strips at room temperature for 6 months or at 4°C for 12 months did not change their sensitivity or specificity. Using RT-PCR as a reference test, the relative specificity and sensitivity of the immunochromatographic strip were determined to be 100% and 97.78%, respectively. There was an excellent agreement between the results obtained by RT-PCR and the immunochromatographic strips (kappa = 0.976). Additionally, there was a strong agreement between the sandwich enzyme-linked immunosorbent assay (ELISA) and immunochromatographic strips (Kappa = 0.976). When the immunochromatographic strips were used for diagnosing PHE-CoV infection in the Jilin Province, the PHE-CoV-positive rate ranged from 61.54% in the Jilin district to 17.95% in the Songyuan district.ConclusionsBased on its high specificity, sensitivity, and stability, the immunochromatographic strip would be suitable for on-site detection of PHE-CoV for surveillance and epidemiological purposes.

Identification and genetic characterization of porcine hemagglutinating encephalomyelitis virus from domestic piglets in China

“…Paraffin sections of cerebral cortex samples from deceased mice inoculated with the PHEV-JT06 isolate were positive for PHEV in the cytoplasm of nerve cells by IHC assay using a mouse anti-PHEV monoclonal antibody ( Fig. 4) [13]. Mice in the control group survived normally.…”

“…Cerebral cortex samples from deceased mice inoculated with the PHEV-JT06 isolate were soaked with ethyl alcohol and dimethylbenzene, embedded in paraffin for 60 minutes, and pretreated with 4 % hydrogen peroxide solution for 30 minutes. The samples were treated with normal goat serum for 3 hours and incubated overnight with mouse anti-PHEV monoclonal antibody [13]. The staining procedure was performed according to the kit instructions.…”

“…In China, PHEV was first reported in 1986; then, several outbreaks of encephalomyelitis in piglets caused by PHEV were reported [9,10]. Several serological surveys revealed a high positive rate of PHEV infections in Jilin and Liaoning provinces [12,13]. Therefore, PHEV infections are widespread in China, at least in the northeast part of the country.…”

The evidence of porcine hemagglutinating encephalomyelitis virus induced nonsuppurative encephalitis as the cause of death in piglets

“…Paraffinembedded sections of brain that had characteristic microscopic lesions were examined by hematoxylin-eosin staining. Selected paraffin sections for PHEV antigen detection by immunohistochemistry (IHC) tests were treated with normal goat serum for 1 hour and anti-HEV 67N monoclonal antibody (Chen et al 2012) (diluted 1:100) overnight; then, the staining procedure was performed according to the kit instructions.…”

The evidence of porcine hemagglutinating encephalomyelitis virus induced nonsuppurative encephalitis as the cause of death in piglets

“…In China, PHEV infection first occurred in Beijing in 1985, and the outbreaks caused enormous economic losses for the pig industry ( Chen et al, 2012 ; Dong et al, 2014 ; Gao et al, 2011 ). Here we report that there is a suspected outbreak of PHEV infection on a farm in Changchun of Jilin Province, in 2014, resulting in serious economic losses.…”