Volume 76, Issue 3
  • ISSN: 0002-9637
  • E-ISSN: 1476-1645


Melanization is an immune response of mosquitoes that could potentially limit development. That mosquitoes rarely melanize in natural populations might result from immuno-suppression by the parasite, as has been observed in mosquitoes infected by . We tested this possibility in mosquitoes infected by by comparing the ability to melanize a Sephadex bead of infected mosquitoes, of mosquitoes that had fed on infectious blood without becoming infected, and of control mosquitoes fed on uninfected blood. Rather than being immuno-suppressed, infected mosquitoes tended to have a stronger melanization response than mosquitoes in which the infection failed and than control mosquitoes, possibly because of immune activation after previous exposure to invading parasites. This finding suggests that relies on immune evasion rather than immuno-suppression to avoid being melanized and confirms that natural malaria transmission systems differ from laboratory models of mosquito– interactions.


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  • Received : 13 Sep 2006
  • Accepted : 18 Nov 2006

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