Serine protease inhibitors have been recognized as key components of parasite secretions and have been implicated in parasite survival through their capacity to inhibit host enzymes, either normally present in the microenvironment and/or secreted by immune effector cells (see, for example, [26]).
Here we studied the effects of immunopathology on infection-induced host mortality rate and lifetime transmission potential – key components of parasite fitness – using the rodent malaria model, Plasmodium chabaudi chabaudi.
The sterol biosynthetic pathway in Trypanosomatidae is an attractive target for the development of antiparasitic agents because ergosterol and related 24-alkyl sterols are essential components of parasite cell membranes.
The first experiment reviewed here showed that one component of parasite virulence is host condition dependent: preadult survival.
Another key component of parasite fitness which has attracted attention in theoretical studies is the evolution of parasite-induced harm to the host, or virulence (Bull 1994).
We explored the effect of immunopathology on key fitness components of the parasite – infection-induced mortality and lifetime transmission potential – using the rodent malaria parasite, Plasmodium chabaudi chabaudi.
On the other hand, our data suggest that the transcriptional downregulation of the pfmdr1-containing amplicon on chromosome 5 (in 106/1 and FCB pfmdr1_3′KD ) might affect parasite physiology, notably through the reduced expression of genes coding for multiple transporters and components of the parasite digestive vacuole, such as ABC and drug/metabolite transporters and V-type ATPases.
Consequently, virulence will result in trade-offs between different components of the parasite's fitness.
The results presented here are the first reported findings regarding the simultaneous interaction of these pathogens in cells that have the potential to kill and control both infections, and identify cruzipain as one of the components of the parasite that interferes with the HIV-1 replication cycle.
This relatively heterogeneous functional category is well represented in the POSP subset and includes proteins implicated in host cell attachment/invasion (10), components of the parasite antioxidant system (2) and members of the LCCL family (5).
