Short Vi-polysaccharide abrogates T-independent immune response and hyporesponsiveness elicited by long Vi-CRM <sub>197</sub> conjugate vaccine
Francesca Micoli, Stefanía P. Bjarnarson, Melissa Arcuri, Auður Anna Aradóttir Pind, Gudbjorg Julia Magnusdottir, Francesca Necchi, Roberta Di Benedetto, Martina Carducci, Fabiola Schiavo, Carlo Giannelli, Ivan Pisoni, Laura B. Martin, Giuseppe Del Giudice, Calman A. MacLennan, Rino Rappuoli, Ingileif Jónsdóttir, Allan Saul
Abstract
Significance Our results suggest a rational way of designing and developing an improved typhoid conjugate vaccine and, by extension, to conjugate vaccines in general: first, modify a T-independent polysaccharide so that it no longer induces a T-independent response, then conjugate the polysaccharide to a suitable carrier protein restoring immunogenicity, thus creating a pure T-dependent antigen that induces a strongly boostable and long-lived response at an early age.