title: Effect of vaccination with a recombinant metalloprotease from Haemaphysalis longicornis.
abstract: We report the cloning, expression and characterization of an Haemaphysalis longicornis metalloprotease (named HLMP1). The gene encodes a predicted 550 aminoacid protein with similarity to metalloproteases of the reprolysin family. The protein sequence contains a signal sequence, the zinc-binding motif (HEXXHXXGXXH) common to metalloproteases and a cysteine-rich region. Reverse transcription-PCR expression analysis indicates the presence of mRNA in the salivary gland of larva, nymph and adult ticks. Rabbit repeatedly infested with H. longicornis recognized rHLMP1, suggesting that the immune-response against HLMP1 is naturally induced through the feeding of ticks. Vaccination of rabbit with rHLMP1 produced protective immunity against ticks, resulting in 15.6 and 14.6% mortality in nymph and adult ticks, respectively. This work provides information to understand the tick's defense system, and offers new insights to develop strategies to block this defense system with an anti-tick vaccine based on a metalloprotease.
authors.affiliation: Department of Disease Control, Graduate School of Veterinary Medicine, Hokkaido University, Kita 18, Nishi 9, Sapporo 060-0818, Hokkaido, Japan.
authors.forename: Saiki
authors.initials: S
authors.lastname: Imamura
authors.forename: Itabajara
authors.initials: I
authors.lastname: da Silva Vaz
authors.forename: Satoru
authors.initials: S
authors.lastname: Konnai
authors.forename: Shinji
authors.initials: S
authors.lastname: Yamada
authors.forename: Chie
authors.initials: C
authors.lastname: Nakajima
authors.forename: Misao
authors.initials: M
authors.lastname: Onuma
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Ohashi
mesh_terms: D020816:Amino Acid Motifs; D000818:Animals; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000378:metabolism; D005247:Feeding Behavior; D026863:Ixodidae / Q000201:enzymology* / Q000235:genetics / Q000276:immunology; D007814:Larva / Q000201:enzymology / Q000276:immunology / Q000378:metabolism; D045726:Metalloproteases / Q000737:chemistry / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D009758:Nymph / Q000201:enzymology / Q000276:immunology / Q000378:metabolism; D010802:Phylogeny; D017434:Protein Structure, Tertiary; D012333:RNA, Messenger / Q000378:metabolism; D011817:Rabbits; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012469:Salivary Glands / Q000201:enzymology / Q000378:metabolism; D013984:Tick Infestations / Q000517:prevention & control*; D014614:Vaccines, Synthetic
chemical_list: D018076:DNA, Complementary; D012333:RNA, Messenger; D014614:Vaccines, Synthetic; D045726:Metalloproteases