With malaria and other vector-borne diseases, we're faced
with problems of not having effective vaccines and insecticide-resistant
vectors. But it seems that mosquitoes do a great job of controlling infection
in their own bodies.
A new study has found that mosquitoes ramp up their immune
system after drinking blood to help fight off the parasites that blood might
contain.
Michael Povelones, an assistant professor in the University of Pennsylvania's
School of Veterinary Medicine, who co-authored the study said that, "This
appears to be a new mechanism by which the mosquito is anticipating a parasite
infection. If we can use that information to our advantage, we might be able to
find new avenues of preventing mosquitoes from transmitting disease."
Scientists already knew that a group of molecules called leucine-rich repeat
immune proteins were important players in mosquitoes' immune defence.
Povelones and colleagues earlier reported that two of these LRIMs, LRIM1 and
APL1C, are part of a signalling pathway akin to the human complement system,
which coordinates immune response through a cascade of signalling interactions.
In mosquitoes, LRIM1 and APL1C helped target malarial parasites for
destruction. In the latest study, the scientists wanted to gain a deeper
understanding of what the other identified LRIM proteins - there are at least
two dozen - did for mosquito immunity.
From their tests, one protein, LRIM9, stood out. When it was
blocked, parasite levels in the mosquitoes increased three-fold.
Researchers found that adult females had the highest
expression levels of LRIM9, with more than 20 times the amount of LRIM9 as
adult males. Adult females are the only mosquitoes that drink blood.
They noted that LRIM9 may help the mosquito immune system
recognise pathogens and may also recruit or interact with other immune system
components. The study was published in the Journal of Innate Immunity.
Source: Medindia
Careers
