Background: Enterococci possess capsular polysaccharide antigens that are the targets of opsonic antibodies. These antibodies are potential candidates for development as immunotherapy.
Material and methods: The present study analyzes the distribution of four capsular serotypes within a collection of 157 isolates of Enterococcus faecalis from four countries with different sites of clinical infection.
Results: By using a capsular polysaccharide-specific ELISA, 42% of the isolates were grouped into one of four serogroups, and another 9% showed cross-reactivity between two serotype-specific sera. Heterogeneity of serotype distribution by both geographical origin and infection site was observed.
Conclusion: Half of the strain collection could be typed with four serotype-specific sera. No serotype from a given country or infection site clearly predominated.