The Characterization of Immunoprotection Induced by a cDNA Clone Derived from the Attenuated Taiwan Porcine Epidemic Diarrhea Virus Pintung 52 Strain.
Journal
Viruses
Journal Volume
10
Journal Issue
10
Date Issued
2018
Author(s)
Kao, Chi-Fei
Chiou, Hue-Ying
Chang, Yen-Chen
Hsueh, Cheng-Shun
Jeng, Chian-Ren
Tsai, Pei-Shiue
Cheng, Ivan-Chen
Pang, Victor Fei
Abstract
The porcine epidemic diarrhea virus (PEDV) poses a great threat to the global swine industries and the unreliable protection induced by the currently available vaccines remains a major challenge. We previously generated a genogroup 2b (G2b) PEDV Taiwan Pintung 52 (PEDVPT) strain, PEDVPT-P96, and determined its promising host immune response against the virulent PEDVPT-P5 strain. To study the attenuation determinants of PEDVPT-P96 and establish a PEDVPT-P96-based recombinant vector as a vaccine platform for further antigenicity modification, iPEDVPT-P96, a full-length cDNA clone of PEDVPT-P96, was established. Comparing to the parental PEDVPT-P96 virus, the iPEDVPT-P96 virus showed efficient replication kinetics with a delayed decline of viral load and similar but much more uniform plaque sizes in Vero cells. In the 5-week-old piglet model, fecal viral shedding was observed in the PEDVPT-P96-inoculated piglets, whereas those inoculated with iPEDVPT-P96 showed neither detectable fecal viral shedding nor PEDV-associated clinical signs. Moreover, inoculation with iPEDVPT-P96 elicited comparable levels of anti-PEDV specific plasma IgG and fecal/salivary IgA, neutralizing antibody titers, and similar but less effective immunoprotection against the virulent PEDVPT-P5 challenge compared to the parental PEDVPT-P96. In the present study, an infectious cDNA clone of an attenuated G2b PEDV strain was successfully generated for the first time, and the in vitro and in vivo data indicate that iPEDVPT-P96 is further attenuated but remains immunogenic compared to its parental PEDVPT-P96 viral stock. The successful development of the iPEDVPT-P96 cDNA clone could allow for the manipulation of the viral genome to study viral pathogenesis and facilitate the rapid development of effective vaccines. ? 2018, MDPI AG. All rights reserved.
SDGs
Other Subjects
complementary DNA; live vaccine; neutralizing antibody; virus antibody; virus vaccine; animal; blood; Chlorocebus aethiops; Coronavirus infection; feces; genetics; immunology; pig; Porcine epidemic diarrhea virus; reverse genetics; serodiagnosis; swine disease; Vero cell line; veterinary medicine; virology; virus genome; virus load; virus shedding; Animals; Antibodies, Neutralizing; Antibodies, Viral; Cercopithecus aethiops; Coronavirus Infections; DNA, Complementary; Feces; Genome, Viral; Neutralization Tests; Porcine epidemic diarrhea virus; Reverse Genetics; Swine; Swine Diseases; Vaccines, Attenuated; Vero Cells; Viral Load; Viral Vaccines; Virus Shedding
Type
journal article