Combined use of released proteins and lipopolysaccharide in enzyme-linked immunosorbent assay for serologic screening of Yersinia infections.

An ELISA for the screening of serum antibodies to Yersinia species was developed using plasmid-encoded released proteins of Yersinia enterocolitica O:8 and lipopolysaccharide of Y. enterocolitica O:3 as a combined antigen. Of 43 sera from patients infected with one of six different Yersinia serotypes, 40 (93%) were positive in this assay. When tested using six serotype-specific ELISAs with the corresponding Yersinia bacteria as antigens, 38 (88%) were positive. This screening ELISA detects antibodies to all virulent yersiniae in one assay and offers the possibility for diagnosis of infections caused by Yersinia serotypes seen only occasionally and not usually included in the serotype-specific ELISAs. Thus, this ELISA offers a substantial advantage by saving time and money in routine laboratory work.