Rabinovitz B C, Vilte D A, Larzábal M, Abdala A, Galarza R, Zotta E, Ibarra C, Mercado E C, Cataldi A
Instituto de Patobiología, Instituto Nacional de Tecnología Agropecuaria (INTA), Argentina.
Instituto de Biotecnología, Instituto Nacional de Tecnología Agropecuaria (INTA), Argentina.
Vaccine. 2014 Jun 24;32(30):3823-9. doi: 10.1016/j.vaccine.2014.04.073. Epub 2014 May 5.
Escherichia coli O157:H7 is responsible for severe intestinal disease and hemolytic uremic syndrome (HUS), a serious systemic complication which particularly affects children. Cattle are the primary reservoir for E. coli O157:H7 and the main source of infection for humans. In this study, we evaluated the ability of transferred maternal colostral antibodies against γ-Intimin C280 and EspB, to protect young weaned calves from E. coli O157:H7 infection. Hyperimmune colostra were obtained by immunization of pregnant cows with a mix of the mentioned antigens. All vaccinated cows mounted a significant IgG response against γ-Intimin C280, and EspB in sera and colostra. Colostrum-fed calves also exhibited high serum IgG titers against γ-Intimin C280 and EspB along with a rise in mucosal γ-Intimin C280-specific IgG antibodies at recto-anal junction and ileum. Additionally, 70 day-old calves received a challenge with E. coli O157:H7 but no reduction in total bacterial shedding or frequency of E. coli O157:H7 excretion from these calves was observed. Most tissue samples showed granulocyte focal infiltrations of the lamina propria and enterocyte erosion. In conclusion, up to the 70th day, the passively acquired γ-Intimin-C280 and EspB-IgG antibodies present in sera and recto-anal mucosa reached a titer insufficient to reduce EHEC O157 shedding and damages of experimentally inoculated young calves.
大肠杆菌O157:H7可引发严重的肠道疾病和溶血尿毒综合征（HUS），这是一种严重的全身性并发症，尤其会影响儿童。牛是大肠杆菌O157:H7的主要宿主，也是人类感染的主要来源。在本研究中，我们评估了经转移的母体初乳抗体针对γ-紧密素C280和EspB保护断奶幼犊免受大肠杆菌O157:H7感染的能力。通过用上述抗原混合物免疫怀孕母牛获得超免疫初乳。所有接种疫苗的母牛血清和初乳中均对γ-紧密素C280和EspB产生了显著的IgG反应。初乳喂养的犊牛血清中针对γ-紧密素C280和EspB也表现出高IgG滴度，同时在直肠-肛门交界处和回肠黏膜γ-紧密素C280特异性IgG抗体有所增加。此外，70日龄的犊牛受到大肠杆菌O157:H7攻击，但未观察到这些犊牛的总细菌排泄量或大肠杆菌O157:H7排泄频率降低。大多数组织样本显示固有层有粒细胞灶性浸润和肠上皮细胞侵蚀。总之，直至第70天，血清和直肠-肛门黏膜中被动获得的γ-紧密素C280和EspB-IgG抗体滴度不足以减少实验接种的幼犊中肠出血性大肠杆菌O157的排泄和损伤。
