Salivary gland thrombostasin isoforms differentially regulate blood uptake of horn flies fed on control- and thrombostasin-vaccinated cattle.
Thrombostasin (TS) is an anticlotting protein found in saliva of Haematobia irritans (horn flies). The polymorphic nature of the ts gene was first associated with success of horn flies blood feeding on a laboratory host, New Zealand White rabbits. In this study, we report results of similar studies testing blood uptake of horn flies feeding on a natural host, cattle. These studies confirmed the association of ts genotype with blood uptake of horn flies and showed that it was host species specific. In contrast to rabbits, blood uptake volumes of homozygous ts10 horn flies were lower than those of other ts genotypes when fed on control (ovalbumin-vaccinated) cattle. Cattle vaccinated with recombinant protein isoforms, rTS9 or rTB8, resisted horn fly feeding by yielding lower blood volumes compared with flies feeding on control cattle. The specific impact of vaccination, however, varied by ts genotype of flies. Cattle vaccinated with isoform rTS9 resisted flies of ts2, ts9, and tb8 genotype. Vaccination with isoform rTB8 produced resistance to ts8, ts9, and tb8 genotype flies. Horn flies of genotype ts10 were not affected by vaccination with either TS isoform and fed as well on rTS9- and rTB8-vaccinated as on control-vaccinated cattle. These experimental results confirm the efficacy of vaccines targeting horn fly salivary proteins and provide new insight into the dynamics of horn fly-cattle interactions in nature.
Cupp
Mary S
MS
Department of Entomology and Plant Pathology, 301 Funchess Hall, Auburn University, Auburn, AL 36849, USA. cuppmar@auburn.edu
Cupp
Eddie W
EW
Navarre
Christine
C
Zhang
Dunhua
D
Yue
Xin
X
Todd
Latora
L
Panangala
Victor
V
D000595:Amino Acid Sequence; D000818:Animals; D000906:Antibodies / Q000097:blood; D002417:Cattle; D005247:Feeding Behavior; D005260:Female; D007300:Insect Control / Q000379:methods*; D019476:Insect Proteins / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D008969:Molecular Sequence Data; D009117:Muscidae / Q000235:genetics* / Q000276:immunology* / Q000502:physiology; D020033:Protein Isoforms; D011817:Rabbits; D012469:Salivary Glands / Q000378:metabolism; D014611:Vaccination; D014614:Vaccines, Synthetic / Q000276:immunology*
D000906:Antibodies; D019476:Insect Proteins; D020033:Protein Isoforms; C439004:Thrombostasin protein, Haematobia irritans; D014614:Vaccines, Synthetic