RT Journal Article SR Electronic T1 Oral administration of an anti-CfaE secretory IgA antibody protects against Enterotoxigenic Escherichia coli diarrheal disease in a non-human primate model JF bioRxiv FD Cold Spring Harbor Laboratory SP 748442 DO 10.1101/748442 A1 Matteo Stoppato A1 Carlos Gaspar A1 James Regeimbal A1 Gladys Nunez A1 Serena Giuntini A1 Melissa A. Gawron A1 Jessica R. Pondish A1 Joseph C. Martin III A1 Matthew Schneider A1 Zachary A. Schiller A1 Mark S. Klempner A1 Lisa A. Cavacini A1 Yang Wang YR 2019 UL http://biorxiv.org/content/early/2019/08/28/748442.abstract AB Enterotoxigenic Escherichia coli (ETEC) is a leading cause of diarrhea-associated illness in developing countries. There is currently no vaccine licensed to prevent ETEC and the development of an efficacious prophylaxis would provide an intervention with significant impact. Recent studies suggested that effective protection could be achieved by inducing immunity to block colonization of ETEC. Here, we evaluated the efficacy of secretory (s) IgA2 and dimeric (d) IgA2 of an anti-colonization factor antigen antibody, 68-61, in the Aotus nancymaae non-human primate (NHP) ETEC challenge model via oral and parental delivery. Thirty-nine animals were distributed across 3 groups of 13, and challenged with 5.0×1011 cfu of H10407 on Day 0. Group 1 received a dIgA2 68-61 subcutaneously on day 0. Group 2 received a SIgA2 68-61 orally on days −1, 0, and +1, and Group 3 received an irrelevant SIgA2 antibody orally on days −1, 0, and +1. All animals were observed for symptoms of diarrhea, and stools were collected for ETEC colony counts. SIgA2 treatment significantly lowered the attack rate, resulting in a protective efficacy of 71.4% (p=0.025) in Group 2 as compared to Group 3. Anti-CfaE dIgA2 treatment group reduced the diarrheal attack rate, although the reduction did not reach significance (57.1%; P=0.072) as compared to the irrelevant SIgA2 Group 3. Our results demonstrated the feasibility of oral administration of SIgA as a potential immunoprophylaxis against enteric infections. To our knowledge, this is the first study to demonstrate the efficacy of administrated SIgA in a non-human primate model.