National Institute of Animal Health (NIAH)

Topics in Animal Health Research 2010

04. Longistatin, a newly identified substance that accelerates blood feeding

Japanese

  Ixodid ticks are serious blood-sucking ectoparasites that are essentially dependent on blood meals from hosts for survival. The feeding mechanism of hard ticks, however, is complex and differs from that of blood-sucking insects that suck blood rapidly and directly from blood vessels. Hard ticks suck blood for a long period (5-10 days or more) by making a large blood pool beneath the skin. Although mammalian hosts are protected by strong blood-clotting machineries, ticks manage to keep the blood in fluid state and to maintain a blood pool until a full blood meal is secured. However, very little is known about the antihemostatic mechanisms by which ticks cleverly manipulate the host's blood-clotting cascade and make blood meals available. Here, we show that longistatin, a salivary gland protein identified from the tick Haemaphysalis longicornis, can efficiently manipulate the host's blood-clotting machineries, such as fibrinogen, fibrin, and plasminogen, and can help prevent the cascade of blood clotting. In conclusion, longistatin plays a crucial role in the blood-feeding success of hard ticks and can be a novel therapeutic target against ticks and tick-borne diseases, including human occlusive cardiovascular diseases such as thrombosis.
(Research Team for Zoonotic Diseases)

References:

  • Anisuzzaman M. et al. (2010) Int. J. Parasitol. 40: 721-729
  • Anisuzzaman M. et al. (2011) PLoS Pathog. 7: e1001312

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