@article{mbs:/content/journal/jgv/10.1099/vir.0.82192-0, author = "Bestagno, Marco and Sola, Isabel and Dallegno, Eliana and Sabella, Patricia and Poggianella, Monica and Plana-Durán, Juan and Enjuanes, Luis and Burrone, Oscar R.", title = "Recombinant dimeric small immunoproteins neutralize transmissible gastroenteritis virus infectivity efficiently in vitro and confer passive immunity in vivo", journal= "Journal of General Virology", year = "2007", volume = "88", number = "1", pages = "187-195", doi = "https://doi.org/10.1099/vir.0.82192-0", url = "https://www.microbiologyresearch.org/content/journal/jgv/10.1099/vir.0.82192-0", publisher = "Microbiology Society", issn = "1465-2099", type = "Journal Article", abstract = "Small immunoproteins (SIPs) are single-chain molecules comprising the variable regions of an antibody assembled in a single polypeptide (scFv) and joined to the immunoglobulin heavy-chain dimerizing domain. To investigate the potential of these molecules to provide protection against enteric infections when supplied orally, SIPs were generated against Transmissible gastroenteritis virus (TGEV), a highly pathogenic porcine virus. Different variants of TGEV-specific SIPs were created, of ε and α isotypes, by exploiting the dimerizing domains εCH4 and αCH3 of human and swine origin. Transfected cells secreted these recombinant mini-antibodies efficiently, mainly as dimers stabilized covalently by inter-chain disulphide bridges. The specificity and functionality of the recombinant TGEV-specific SIPs were determined by in vitro binding, neutralization and infection-interference assays. The neutralization indices of the TGEV-specific SIPs were all very similar to that of the original TGEV-specific mAb, thus confirming that the immunological properties have been preserved in the recombinant SIPs. In vivo protection experiments on newborn piglets have, in addition, demonstrated a strong reduction of virus titre in infected tissues of animals treated orally with TGEV-specific SIPs. It has therefore been demonstrated that it is possible to confer passive immunization to newborn pigs by feeding them with recombinant SIPs.", }