Romero-Saavedra, FelipeLaverde, DianaKalfopoulou, ErmioniMartini, CeciliaTorelli, RiccardoMartínez Matamoros, DianaSanguinetti, MaurizioHuebner, Johannes2019-11-052019-11-052019-07-09F Romero-Saavedra, D Laverde, E Kalfopoulou, C Martini, R Torelli, D Martinez-Matamoros, M Sanguinetti, J Huebner, Conjugation of Different Immunogenic Enterococcal Vaccine Target Antigens Leads to Extended Strain Coverage, The Journal of Infectious Diseases, Volume 220, Issue 10, 15 November 2019, Pages 1589–1598, https://doi.org/10.1093/infdis/jiz3570022-18991537-6613http://hdl.handle.net/2183/24230[Abstract] Enterococci have emerged as important nosocomial pathogens due to their resistance to the most commonly used antibiotics. Alternative treatments or prevention options are aimed at polysaccharides and surface-related proteins that play important roles in pathogenesis. Previously, we have shown that 2 Enterococcus faecium proteins, the secreted antigen A and the peptidyl-prolyl cis-trans isomerase, as well as the Enterococcus faecalis polysaccharide diheteroglycan, are able to induce opsonic and cross-protective antibodies. Here, we evaluate the use of glycoconjugates consisting of these proteins and an enterococcal polysaccharide to develop a vaccine with broader strain coverage. Diheteroglycan was conjugated to these 2 enterococcal proteins. Rabbit sera raised against these glycoconjugates showed Immunoglobulin G titers against the corresponding conjugate, as well as against the respective protein and carbohydrate antigens. Effective opsonophagocytic killing for the 2 sera was observed against different E. faecalis and E. faecium strains. Enzyme-linked immunosorbent assays against whole bacterial cells showed immune recognition of 22 enterococcal strains by the sera. Moreover, the sera conferred protection against E. faecalis and E. faecium strains in a mouse infection model. Our results suggest that these glycoconjugates are promising candidates for vaccine formulations with a broader coverage against these nosocomial pathogens and that the evaluated proteins are potential carrier proteins.engAtribución-NoComercial-SinDerivadas 3.0 Españahttp://creativecommons.org/licenses/by-nc-nd/3.0/es/VaccineGlycoconjugateCarrier proteinCapsular polysaccharideDiheteroglycanEnterococcal proteinsEnterococcus faecalisEnterococcus faeciumOpsonophagocytic assayMouse infection modeljournal articleopen access