A multivalent mRNA-LNP vaccine protects against <i>Clostridioides difficile</i> infection.

Abstract

<i>Clostridioides difficile</i> infection (CDI) is an urgent public health threat with limited preventative options. In this work, we developed a messenger RNA (mRNA)-lipid nanoparticle (LNP) vaccine targeting <i>C. difficile</i> toxins and virulence factors. This multivalent vaccine elicited robust and long-lived systemic and mucosal antigen-specific humoral and cellular immune responses across animal models, independent of changes to the intestinal microbiota. Vaccination protected mice from lethal CDI in both primary and recurrent infection models, and inclusion of non-toxin cellular and spore antigens improved decolonization of toxigenic <i>C. difficile</i> from the gastrointestinal tract. Our studies demonstrate mRNA-LNP vaccine technology as a promising platform for the development of novel <i>C. difficile</i> therapeutics with potential for limiting acute disease and promoting bacterial decolonization.