Comparative study of mannose-binding C-type lectin isolated from channel catfish ( Ictalurus punctatus) and blue catfish ( Ictalurus furcatus)

• Published in: Fish & shellfish immunology Vol. 23; no. 6; pp. 1152 - 1160
• Main Authors: Ourth, Donald D., Narra, Madhu B., Simco, Bill A.
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01-12-2007
• Subjects: Animals; Blotting, Western; Chromatography, Affinity - veterinary; Comparison; Edwardsiella ictaluri; Edwardsiella ictaluri - immunology; Freshwater; Guinea Pigs; Ictaluridae - immunology; Ictalurus furcatus; Ictalurus punctatus; Ictalurus species; Immunoglobulin G - biosynthesis; Immunoglobulin G - metabolism; Isolation; Mannose-binding lectin; Mannose-Binding Lectin - blood; Mannose-Binding Lectin - chemistry; Mannose-Binding Lectin - isolation & purification; Mannose-Binding Lectin - metabolism; Species Specificity; Isolation; Comparison; Mannose-binding lectin; Ictalurus species
• ISSN: 1050-4648; 1095-9947
• DOI: 10.1016/j.fsi.2007.03.014

Mannose-binding C-type lectin (MBL) was isolated from channel catfish (
Ictalurus punctatus) NWAC 102 and 103 strains, blue catfish (
Ictalurus furcatus) D+B and Rio Grande strains, hybrid catfish (channel catfish female NWAC 103
×
blue catfish male D+B) sera, and purified by affinity chromatography from channel catfish Norris strain serum. Reduction of purified channel catfish MBL with 2-ME yielded a single band of 62
kDa by SDS–PAGE and Western blot analysis using guinea pig anti-MBL IgG as primary antibody. Channel catfish NWAC 102 strain, channel catfish NWAC 103 strain and hybrid catfish sera had molecular masses of 63
kDa for MBL. Blue catfish (D+B strain) serum MBL had a molecular mass of 66
kDa. Rio Grande blue catfish serum MBL had a molecular mass of 65
kDa. Amino acid composition analysis (mol%) of the affinity-purified channel catfish MBL found a high content of serine present. Functional binding studies of channel catfish and blue catfish MBLs binding to
Edwardsiella ictaluri were done using a dot-immunoblot ELISA method. A dot-immunoblot ELISA binding assay was done to compare nine different strains and species of channel catfish and blue catfish for their levels of serum MBL. Blue catfish had higher levels of MBL than did the various strains of channel catfish tested. MBL could be used as a genetic marker for selection of disease resistance in the different strains of catfish used in aquaculture. This study describes the presence of serum MBL in catfish and evidence for a C-type lectin complement pathway of innate immunity.