Maj Magdalena, Fake Gina M, Walker John H, Saltzman Ryan, Howard John A
Department of Biological Sciences, California Polytechnic State University, San Luis Obispo, CA 93407, USA.
Applied Biotechnology Institute, Cal Poly Tech Park, San Luis Obispo, CA 93407, USA.
Vaccines (Basel). 2021 Nov 30;9(12):1416. doi: 10.3390/vaccines9121416.
To investigate whether oral administration of maize-produced S antigen can provide passive immunity to piglets against porcine epidemic diarrhea virus (PEDV), 16 pregnant sows were randomly assigned to one of four treatments: (1) injection of PEDV vaccine (INJ), (2) maize grain without S protein (CON), (3) maize grain containing low dose of S antigen (LOV) and (4) maize grain containing a high dose of S antigen (HOV). Vaccines were administered on days 57, 85 and 110 of gestation. Sows' serum and colostrum were collected at farrowing and milk on day 6 post-challenge to quantify neutralizing antibodies (NABs) and cytokines. Piglets were challenged with PEDV 3-5 d after farrowing, and severity of disease and mortality assessed on day 11 post-challenge. Disease severity was lower in LOV and INJ compared with HOV and CON, whereas the survival rate increased in piglets from LOV sows compared with HOV and CON ( ≤ 0.001). Higher titers of NABs and lower levels of cytokine granulocyte-macrophage colony-stimulating factor in sows' milk were positively correlated with piglet survivability ( ≤ 0.05). These data suggest that feeding S protein in corn to pregnant sows protects nursing piglets against PEDV.
为了研究口服玉米生产的S抗原是否能为仔猪提供针对猪流行性腹泻病毒（PEDV）的被动免疫，16头怀孕母猪被随机分配到四种处理之一：（1）注射PEDV疫苗（INJ），（2）不含S蛋白的玉米粒（CON），（3）含有低剂量S抗原的玉米粒（LOV）和（4）含有高剂量S抗原的玉米粒（HOV）。在妊娠第57、85和110天接种疫苗。在分娩时收集母猪的血清和初乳，并在攻毒后第6天收集乳汁，以定量中和抗体（NABs）和细胞因子。仔猪在分娩后3 - 5天用PEDV攻毒，并在攻毒后第11天评估疾病严重程度和死亡率。与HOV和CON相比，LOV和INJ组的疾病严重程度较低，而与HOV和CON相比，LOV组母猪的仔猪存活率增加（≤0.001）。母猪乳汁中较高滴度的NABs和较低水平的细胞因子粒细胞 - 巨噬细胞集落刺激因子与仔猪存活率呈正相关（≤0.05）。这些数据表明，给怀孕母猪喂食玉米中的S蛋白可保护哺乳仔猪免受PEDV感染。
