Chemistry-Driven Dissection of Malaria Immunity and Resistance: Multiplex Antibody Analysis and Mechanistic Inhibition Studies

Abstract

This dissertation discusses the dissection of antimalarial immunity and resistance, with an emphasis on chemistry-driven tools for antibody analysis and parasite inhibition. Malaria remains a major global health burden, and despite the availability of frontline therapeutics, widespread resistance and incomplete immune protection underscore the urgent need for new strategies. To address these challenges, this work integrates chemical biology approaches to interrogate antibody responses, evaluate drug efficacy, and characterize host-parasite interactions during the erythrocytic life cycle.First, bead-based multiplexing assays were developed and optimized as a platform for the simultaneous analysis of antibody responses against multiple malaria antigens. By applying advanced coupling chemistries and addressing limitations in antigen production and orientation, this platform enabled high-throughput, sensitive, and reproducible profiling of naturally acquired immunity. These innovations provide an improved chemical framework for antigen prioritization and vaccine candidate evaluation. Second, mechanistic growth inhibition assays (GIAs) were employed to investigate parasite susceptibility to small molecules, monoclonal antibodies, and patient sera. Using well-characterized compounds such as Tartrolon E, DSM265, and artemisinin as pharmacological benchmarks, these assays established a robust comparative system for evaluating inhibitory potency. Parallel studies with monoclonal antibodies targeting key invasion ligands (MSP1, AMA1, EBA175) highlighted distinct inhibitory profiles and stage-specific vulnerabilities, while patient sera from a malaria-endemic region revealed protective capacity that complements drug and antibody-mediated mechanisms. Finally, resistance studies focused on dihydroorotate dehydrogenase (DHODH) inhibitors, a promising class of antimalarials. Cross-resistance analyses of DSM265-resistant P. falciparum mutant lines against a panel of novel DHODH inhibitors revealed susceptibility patterns. These findings provide critical insights into drug-target interactions and resistance evolution, informing future drug design strategies. Together, this dissertation demonstrates how chemical tools and mechanistic assays can be harnessed to dissect the molecular basis of antimalarial immunity and drug resistance. The integration of multiplex immunoassays, pharmacological profiling, and resistance mapping establishes a versatile framework for advancing vaccine development, drug discovery, and malaria research.