POTENTIAL ANTIGENTS FOR MALARIA VACCINE: A NEW HOPE FOR MALARIA ELIMINATION

Abstract

Malaria is a dangerous mosquito-borne disease caused by Plasmodium parasite. The disease
threatens more than half of the world's population. Malaria prevention and treatment rely on
synthetic medications, but the parasites have evolved resistance to all classes of drugs advised.
This, together with the high prevalence of malaria in the developing world, highlights the urgent
need for vaccine development. The purpose of this paper was to review the current level of
knowledge on various Plasmodium antigens that can elicit the appropriate immune response.
Several malaria vaccine candidates are moving forward, with more than 30 in advanced
preclinical or clinical phases of development. However, only the RTS,S/AS01 vaccine has
completed Phase III testing and got a favourable regulatory assessment. Pre-erythrocytic
Vaccines (PEVs), Blood-Stage Vaccines (BSVs), and Transmission-Blocking Vaccines are the
three types of malaria vaccines (TBVs). The majority of PEV research is currently focused on
the development of subunit vaccines against parasite proteins such as the Pf circumsporozoite
protein (PfCSP), the thrombospondin-related adhesion protein (TRAP), and the liver stage
antigen (LSA). BSVs attack the parasite's blood stages. Two of the most likely BSV candidates
are P. falciparum merozoite surface protein-1 (PfMSP1) and P. falciparum Apical Membrane
Antigen-1 (PfAMA1). The most advanced contender is Plasmodium falciparum Reticulocytebinding
protein homolog 5 (PfRH5). TBVs interfere with the parasite's sexual development in
the vector. Pfs25, P230, P48/45, Pfs2400, Pfg 27, Ps28, and Ps21 proteins are powerful antigens
in TBVs because they are found at various phases of the parasite's growth while in the mosquito.
With the availability of many various antigens, a malaria vaccine could be developed in the near
future. More study into the practical application of these antigens is needed in order to produce a
malaria vaccine quickly.