Assessment of cathepsin D and L-like proteinases of poultry red mite, Dermanyssus gallinae (De Geer), as potential vaccine antigens.
Vaccination is a feasible strategy for controlling the haematophagous poultry red mite Dermanyssus gallinae. A cDNA library enriched for genes upregulated after feeding was created to identify potential vaccine antigens. From this library, a gene (Dg-CatD-1) encoding a 383 amino acid protein (Dg-CatD-1) with homology to cathepsin D lysosomal aspartyl proteinases was identified as a potential vaccine candidate. A second gene (Dg-CatL-1) encoding a 341 amino acid protein (Dg-CatL-1) with homology to cathepsin L cysteine proteinases was also selected for further study. IgY obtained from naturally infested hens failed to detect Dg-CatD-1 suggesting that it is a concealed antigen. Conversely, Dg-CatL-1 was detected by IgY derived from natural-infestation, indicating that infested hens are exposed to Dg-CatL-1. Mortality rates 120 h after mites had been fed anti-Dg-CatD-1 were significantly higher than those fed control IgY (PF<0·01). In a survival analysis, fitting a proportional hazards model to the time of death of mites, anti-Dg-CatD-1 and anti-Dg-CatL-1 IgY had 4·42 and 2·13 times higher risks of dying compared with controls (PF<0·05). Dg-CatD-1 and L-1 both have potential as vaccine antigens as part of a multi-component vaccine and have the potential to be improved as vaccine antigens using alternative expression systems.
Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, Midlothian EH26 0PZ, Scotland, UK. Kathryn.Bartley@moredun.ac.uk
Kathryn
K
Bartley
John F
JF
Huntley
Harry W
HW
Wright
Mintu
M
Nath
Alasdair J
AJ
Nisbet
D000595:Amino Acid Sequence; D000818:Animals; D000906:Antibodies / Q000097:blood; D000941:Antigens / Q000235:genetics / Q000276:immunology; D002402:Cathepsin D / Q000235:genetics / Q000276:immunology*; D056668:Cathepsin L / Q000235:genetics / Q000276:immunology*; D002645:Chickens / Q000469:parasitology; D005260:Female; D008924:Mite Infestations / Q000276:immunology / Q000469:parasitology / Q000517:prevention & control / Q000662:veterinary*; D008925:Mites / Q000201:enzymology* / Q000276:immunology; D008969:Molecular Sequence Data; D011201:Poultry Diseases / Q000276:immunology / Q000517:prevention & control*; D011994:Recombinant Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D017422:Sequence Analysis, DNA; D014612:Vaccines / Q000276:immunology*
D000906:Antibodies; D000941:Antigens; D011994:Recombinant Proteins; D014612:Vaccines; D056668:Cathepsin L; D002402:Cathepsin D