Article

Surface antigens of Plasmodium falciparum gametocytes--a new class of transmission-blocking vaccine targets?

HPA Malaria Reference Laboratory, Department of Infectious & Tropical Diseases, London School of Hygiene & Tropical Medicine, Keppel Street, London WC1E 7HT, United Kingdom.
Molecular and Biochemical Parasitology (impact factor: 2.55). 09/2009; 166(2):93-8. DOI:10.1016/j.molbiopara.2009.03.007
Source: PubMed

ABSTRACT The re-establishment of elimination and eradication on the malaria control agenda has led to calls for renewed effort in the development of parasite transmission-blocking interventions. Vaccines are ideally suited to this task, but progress towards an anti-gamete transmission-blocking vaccine, designed to act on parasites in blood-fed mosquitoes, has been slow. Recent work has confirmed that the surface of the gametocyte-infected erythrocyte presents antigens to the host immune system, and elicits specific humoral immune responses to these antigens, termed gametocyte surface antigens (GSAs). Likely candidate molecules, including antigens encoded by sub-telomeric multi-gene families, are discussed, and a hypothetical group of parasite molecules involved in spatial and temporal signal transduction in the human host is proposed, the tropins and circadins. The next steps for development of anti-gametocyte transmission-blocking vaccines for P. falciparum and the other human malaria species are considered.

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Keywords

anti-gamete transmission-blocking vaccine
 
anti-gametocyte transmission-blocking vaccines
 
antigens
 
antigens encoded
 
elicits specific humoral immune responses
 
eradication
 
gametocyte surface antigens
 
gametocyte-infected erythrocyte presents antigens
 
host immune system
 
Likely candidate molecules
 
next steps
 
P. falciparum
 
parasite transmission-blocking interventions
 
parasites
 
temporal signal transduction
 
tropins
 
Vaccines
 

Colin J Sutherland