A spike-specific whole-porcine antibody isolated from a porcine B cell that neutralizes both genogroup 1 and 2 PEDV strains

Abstract

Porcine epidemic diarrhea (PED), caused by an alpha coronavirus, is a highly contagious disease and causes high morbidity and mortality in suckling piglets. Isolating PEDV neutralizing antibodies from porcine B cells is critical to elucidate the development of PEDV neutralizing antibodies and the protective mechanism of PEDV infection. Here, we described the isolation of a PEDV-neutralizing antibody from the B cell of a vaccinated pig. The antibody, named PC10, was demonstrated to target the conformational epitope of PEDV spike protein, specifically bind to the infected cells of PEDV genogroup 1 and 2 strains, and potently neutralize PEDV infection. PC10 neutralized PEDV infection through interfering with the viral life stages after cellular attachment instead of blocking the attachment of PEDV to cells. These results suggest that PC10 could be a promising candidate for passive protection and inform PEDV vaccine design because of its specificity and substantial neutralization potency.

The S Gene Is Necessary but Not Sufficient for the Virulence of Porcine Epidemic Diarrhea Virus Novel Variant Strain BJ2011C

“…The S proteins of the highly virulent variants of PEDV have multiple amino acid insertions, deletions, and substitutions relative to the classic PEDV strains (e.g., CV777) (20). Since S protein is critically involved in PEDV entry, assembly, and induction of neutralizing antibodies (30,33,38,40,(54)(55)(56), the mutations likely have an influence on the virulence of PEDV. This idea is partly supported by recent studies of PEDV S protein large deletion mutants that were isolated from either cell culture (strain TC-PC177; cell adapted) (57) or swine farms (strain TTR-2) (58).…”

Neutralizing antibodies against porcine epidemic diarrhea virus block virus attachment and internalization

“…Additionally, for other nAbs, infection can be blocked through inhibiting critical intracellular processes, for example rotavirus transcription [17], nuclear translocation of human papilloma virus DNA [18], adenoviral uncoating [19], or measles virus assembly [20]. Several studies demonstrated that spike mAb can neutralize PEDV [21][22][23][24][25][26]. These studies mainly focused on locating the neutralizing domains of PEDV S protein, however, the mechanisms by which spike nAb neutralize the virus have not been defined completely.…”

Development of whole-porcine monoclonal antibodies with potent neutralization activity against classical swine fever virus (CSFV) from single B cells

“…The neutralization activity of the mAbs HK24 and HK44 against CSFV was tested via an immunofluorescence assay as described previously (54). Briefly, PK-15 cells were grown to 30-40% confluence in complete DMEM containing 10% FBS on 96-well plates at 37°C in 5% CO 2 .…”