Researchers have employed two complementary approaches, to identify 27 novel extracellular antigens secreted by Plasmodium falciparum at asexual blood stages1. The study provides insight into the malaria immune evading mechanisms and could lead to development of new drug and inhibitors that can block immune evasion by the parasite.

The two approaches used by the researchers are a two dimensional gel electrophoresis/mass spectrometry and liquid chromatography/tandem mass spectrometry (LC-MS/MS).

The success of malaria parasite in human host depends on a series of intricate and highly evolved adaptations that enables the parasite to evade destruction by the host immune system. The efficiency with which the parasites avoid clearance and persists in host is probably determined by surface and secretory antigens.

"Many of the identified antigens are predicted extracellular proteins that interact with cell surface proteins to down regulate immune responses and signaling," says one of the authors Pawan Malhotra.

Preliminary functional characterization of two novel antigens, PfSel-1 & PfSel-2 revealed that these antigens down-regulate expression of cell surface Notch signaling pathway in host cells.