Identification of Shigella and enteroinvasive Escherichia coli strains by a virulence-specific, monoclonal antibody-based enzyme immunoassay.
BALB/c mice were immunised with water extracts made from an Escherichia coli K-12 strain harbouring the shigella invasion plasmid, and hybridomas secreting antibodies specific to invasion plasmid-coded antigens were selected. On Western blots, antibodies produced by one of these clones (MAIC-1) recognised a protein of 43 kDa, which is the molecular mass of invasion plasmid coded antigen C (IpaC). When used in enzyme immunoassay against whole bacterial cells or against proteins secreted by actively growing bacteria, MAIC-1 clearly differentiated between invasive and non-invasive strains. Testing 123 enteroinvasive and 139 non-enteroinvasive strains the MAIC-1 based assay proved to be highly specific and sensitive in recognising enteroinvasive isolates. This test could be an inexpensive and rapid alternative to cumbersome virulence assays and a helpful technique in identifying Shigella or enteroinvasive Escherichia coli isolates.
Floderus
E
E
Department of Clinical Bacteriology, Karolinska Institute, Huddinge Hospital, Sweden.
Pál
T
T
Karlsson
K
K
Lindberg
A A
AA
D000818:Animals; D000911:Antibodies, Monoclonal; D000942:Antigens, Bacterial / Q000032:analysis; D004405:Dysentery, Bacillary / Q000175:diagnosis* / Q000382:microbiology; D004926:Escherichia coli / Q000145:classification* / Q000276:immunology / Q000472:pathogenicity; D004927:Escherichia coli Infections / Q000175:diagnosis* / Q000382:microbiology; D006168:Guinea Pigs; D007124:Immunoenzyme Techniques; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D012760:Shigella / Q000145:classification* / Q000276:immunology / Q000472:pathogenicity; D014774:Virulence
D000911:Antibodies, Monoclonal; D000942:Antigens, Bacterial