Antigenic variation at the infected red cell surface in malaria

Area of Science:

• Parasitology
• Immunology
• Molecular Biology

Background:

• Many pathogens have evolved immune evasion strategies to ensure long-term host survival.
• Clonal antigenic variation is a common immune evasion mechanism used by pathogens like Plasmodium, Trypanosoma, and Borrelia.

Purpose of the Study:

• To review the history and recent data on antigenic variation in malaria parasites.
• To focus on Plasmodium falciparum, the causative agent of severe human malaria.

Main Methods:

• Review of historical and current scientific literature on antigenic variation.
• Analysis of gene families encoding surface molecules involved in immune evasion.
• Emphasis on Plasmodium falciparum as a model system.

Main Results:

• Antigenic variation relies on the sequential expression of diverse surface molecules from multicopy, nonallelic gene families.
• These molecules are targets of the host's humoral immune response.
• In Plasmodium, some variant surface molecules are also critical virulence factors.

Conclusions:

• Antigenic variation is a key survival strategy for Plasmodium falciparum, complicating host-parasite interactions.
• Understanding this mechanism is crucial for developing effective malaria control strategies.