Malaria Flashcards
1
Q
Outline the lifecycle of Malaria
A
- Female anopheles mosquito delivers sporozoites into the blood
- Merozoites release invasion proteins that bind to RBC receptors
- Parasitovorous vacuole absorbs parasite into cell
- Perforin-like-proteins lyse RBC membrane, causing egress of new merozoites.
- Gametogenesis occurs in mosquito when taken up
2
Q
How does sickle cell anaemia protect from Malaria?
A
- HbAS decreases the habitability inside RBCs, especially under low oxygen tension
- Decreased endothelial adherence due to reduced parasite protein expression
- Increased removal of RBCs by spleen clears the parasite more than normal
3
Q
What host protein does P. Vivax require in order to invade human red cells?
A
Duffy antigen receptor for chemokines (DARC)
4
Q
How does the disruption of the cytoskeletal network associated with HbS and HbC deter the pathogenesis of Malaria?
A
Parasites rely on host-derived cytoskeletal proteins to traffic essential parasite proteins to the RBC membrane.
5
Q
What blood group systems offer malarial protection?
A
ABO, Duffy, S-sU
6
Q
How may HbAS assist in malarial immunity?
A
Prolonged subclinical/mild parasitaemia is often seen in children with HbAS infected with P. falciparum. This provides the host with sufficient opportunity to develo[ humoral immunity against the infection.
