Oral immunization with aLactobacillus casei-based anti-porcine epidemic diarrhoea virus (PEDV) vaccine expressing microfold cell-targeting peptide Co1 fused with the COE antigen of PEDV

Abstract

Lactobacillus casei delivering the COE antigen of PEDV conjugated with a M cell-targeting peptide Co1 as an immune adjuvant is a promising oral vaccine candidate for PEDV.

Recombinant Lactobacillus casei Expressing Capsid Protein VP60 can Serve as Vaccine Against Rabbit Hemorrhagic Disease Virus in Rabbits

“…Recombinant L. casei pPG-eGFP-VP60/LC393 induced a higher level of sIgA compared with that induced by the inactivated virus vaccine, indicating that L. casei pPG-eGFP-VP60/LC393 was more efficient at eliciting mucosal immune responses, and there were almost no significant differences of sIgA and IgG antibody levels in the experimental animals administered with pPG/L. casei 393 and PBS, which have been confirmed in our previous studies [31,35,51]. Previous studies also have shown that oral vaccines elicit stronger mucosal immune responses than do injected vaccines [46].…”

“…The multiple immunization procedure of recombinant Lactobacillus was employed in this study was due to the amounts of recombinant Lactobacillus adhered to the intestinal mucosa were decreased with the time [57]. The immune effect of the multiple immunization procedure of recombinant Lactobacillus has been confirmed in the previous studies [31,35]. The rabbits were immunized with inactivated vaccine according to the instruction.…”

“…As an oral vaccine vector, L. casei offers many advantages, such as increased safety, resistance to the harsh GI environment, robust capacity for intestinal colonization, and nonspecific immunoadjuvant effect [47][48][49]. Previously, live vector-based oral vaccines were constructed using LC393, a promising strain of L. casei that can deliver antigenic material to the mucosa and express numerous targeted proteins, such as VP2 protein of porcine parvovirus (PPV), glycoprotein E2 of bovine viral diarrhea virus (BVDV), spike protein (S) of transmissible gastroenteritis virus (TGEV), and core neutralizing epitope (COE) antigen of porcine epidemic diarrhea virus (PEDV) [35,[50][51][52]. Oral vaccination with these vaccines can efficiently induce mucosal, humoral, and cellular immune responses, indicating that LC393 is an excellent vector for use in oral vaccines.…”

“…Currently, there is increasing interest in the development of L. casei oral vaccines, and this approach is significant for the effective induction of a mucosal immune response [30]. The results to date have been confirmed that the safety and the effectiveness of L. casei were used as the oral vaccine vehicle, which were extensively used in protecting individuals against a variety of pathogens [31][32][33][34][35][36][37].…”

“…Serum, nasal washes, vaginal lotions, tears, and fecal samples were obtained on days 0, 7, 14, 21, 28, and 35 after immunization, and were stored at −20 • C until use. Fecal samples were pretreated according to a previously published method [35].…”