Use of monoclonal antibodies in the indirect fluorescent antibody technique (IFA) for the diagnosis of Edwardsiella ictaluri*

Abstract

Forty-five channel catfish, Ictalurus punctatus (Rafinesque), fingerlings were inoculated with Edwardsiella ictaluri to determine the usefulness of monoclonal antibodies for indirect fluorescent antibody techniques for confirming clinical diagnosis of enteric septicaemia of catfish. Bacteriological and indirect fluorescent antibody results were compared statistically and found to correlate in 90 3% of the cases. A method for incorporating monoclonals for indirect fluorescent antibody into the speciation of Edwardsiella ictaluri and the use of monoclonal antibodies in diagnosis is described.

Comparison of Edwardsiella ictaluri isolates from different hosts and geographic origins

“…In addition, they reported consistently different plasmid profiles (two plasmids of 4.0 and 3.5 kb) and failure of the monoclonal antibody (Ed9) (Ainsworth et al . ), raised against a Mississippi catfish isolate of E. ictaluri , to react with the zebrafish isolate. Contrary to the aforementioned, Soto et al .…”

“…Hawke et al (2013) demonstrated that isolates from zebrafish comprised a unique phenotypic group exhibiting weaker motility, autoaggregation in broth and a slightly different API 20E code (420400). In addition, they reported consistently different plasmid profiles (two plasmids of 4.0 and 3.5 kb) and failure of the monoclonal antibody (Ed9) (Ainsworth et al 1986), raised against a Mississippi catfish isolate of E. ictaluri, to react with the zebrafish isolate. Contrary to the aforementioned, Soto et al (2012) did not report any observable phenotypic differences between E. ictaluri from tilapia and E. ictaluri from catfish.…”

Edwardsiellosis Caused by Edwardsiella ictaluri in Laboratory Populations of Zebrafish Danio rerio

“…Separated samples were transferred to a polyvinylidene fluoride membrane using the iBlot Dry Transfer System (Life Technologies). The membrane was incubated with the Ed9 lipopolysaccharide (LPS) monoclonal antibody raised against the ATCC 33202 isolate of E. ictaluri, donated by Dr. Jerold Ainsworth, Mississippi State University (Ainsworth et al 1986), diluted 1:8 in tris-buffered saline containing 0.1% Tween-20 (Bio-Rad Laboratories, Hercules, California). Horseradish peroxidase-conjugated goat anti-mouse antibody (Thermo-Fisher Scientific,× Rockford, Illinois) was used to label the Ed9 antibody with Super-Signal West Pico chemiluminescent substrate (Thermo-Fisher Scientific).…”

The Edwardsiella ictaluri O polysaccharide biosynthesis gene cluster and the role of O polysaccharide in resistance to normal catfish serum and catfish neutrophils

“…Ampicillin-resistant Ed. ictaluri were transferred onto nitrocellulose membranes by colony lifts, and colony blots were done as previously described ) using the mAb Ed9 (Ainsworth et al, 1986), which is specific for Ed. ictaluri OPS.…”