Role of Type 1 Fimbriae in the Pathogenesis of Salmonella Infections: Twenty Five Years of Personal Research

Type 1 fimbriae are surface structures produced by all Salmonella serovars. It is generally accepted that these appendages play an important role in early stages of Salmonella infections, being responsible for the attachment and colonization of gut mucosa by the pathogens. Nevertheless, despite many years of research, their exact role in the pathogenesis of infections caused by these bacilli remains far from fully understood. The same applies to the role of the FimH adhesin of type 1 fimbriae, which directly contributes to their adhesive properties. In this review article, I summarize the major findings on FimH adhesins from different Salmonella serovars (Enteritidis, Gallinarum, Choleraesuis, Dublin, and Abortusovus), the result of 25 years of research on this topic. Our studies focused on the adhesive properties of these adhesins, including their interactions with specific ligands and the identification of cellular receptors, as well as their role in Salmonella host specificity.