bioRxiv Science⌕ Search

Biology subjects

Wang, L. T.

Publications and source records attributed to Wang, L. T..

5 recordsLinked to original sources

Natural malaria infection elicits rare but potent neutralizing antibodies to the blood-stage antigen RH5

Plasmodium falciparum RH5 is the most advanced blood-stage malaria vaccine candidate and is under evaluation for efficacy in endemic regions, emphasizing the need to study the underlying antibody response to RH5 during natural infection. Here, we found that RH5-reactive B cells were rare in malaria-exposed individuals despite repeated infections over multiple years. RH5-specific monoclonal antibodies isolated from these individuals were extensively mutated but mostly targeted non-neutralizing epitopes, in contrast to antibodies from RH5-vaccinated, malaria-naive individuals. However, infection-derived MAD8-151 and MAD8-502 were among the most potent neutralizers out of 186 antibodies isolated from both cohorts and target the same epitopes as the most effective vaccine-induced antibodies. Binding to basigin receptor-proximal epitopes was the primary factor governing the potency of RH5-specific antibodies from both natural infection and vaccination, followed by the strength of binding. These results indicate a clear strategy for the development of next-generation RH5 vaccines for use in malaria-endemic regions.

immunology↗

Analysis of the Diverse Antigenic Landscape of the Malaria Invasion Protein RH5 Identifies a Potent Vaccine-Induced Human Public Antibody Clonotype

The highly conserved and essential Plasmodium falciparum reticulocyte-binding protein homolog 5 (PfRH5) has emerged as the leading target for vaccines that seek to protect against the disease-causing blood-stage of malaria. However, the features of the human vaccine-induced antibody response that confer highly potent inhibition of malaria parasite invasion into red blood cells are not well defined. Here we characterize over 200 human IgG monoclonal antibodies induced by the most advanced PfRH5 vaccine. We define the antigenic landscape of this molecule, and establish epitope specificity, antibody association rate and intra-PfRH5 antibody interactions are key determinants of functional anti-parasitic potency. In addition, we identify a germline gene combination that results in an exceptionally potent class of antibody and demonstrate its prophylactic potential to protect against P. falciparum parasite challenge in vivo. This comprehensive dataset provides a framework to guide rational design of next-generation vaccines and prophylactic antibodies to protect against blood-stage malaria.

immunology↗

The light chain of the L9 antibody is critical for binding circumsporozoite protein minor repeats and preventing malaria

L9 is a potent human monoclonal antibody (mAb) that preferentially binds two adjacent NVDP minor repeats and cross-reacts with NANP major repeats of the Plasmodium falciparum circumsporozoite protein (PfCSP) on malaria-infective sporozoites. Understanding this mAbs ontogeny and mechanisms of binding PfCSP to neutralize sporozoites will facilitate vaccine development. Here, we isolated mAbs clonally related to L9 and showed that this B-cell lineage has baseline NVDP affinity and evolves to acquire NANP reactivity. Pairing the L9 kappa light chain (L9{kappa}) with clonally-related heavy chains resulted in chimeric mAbs that cross-linked two NVDP, cross-reacted with NANP, and more potently neutralized sporozoites compared to their original light chain. Structural analyses revealed that chimeric mAbs bound the minor repeat motif in a type-1 {beta}-turn seen in other repeat-specific antibodies. These data highlight the importance of L9{kappa} in binding NVDP on PfCSP to neutralize SPZ and suggest that PfCSP-based immunogens might be improved by presenting [≥]2 NVDP.

immunology↗

Association of SRB1, ITGB2 gene polymorphisms with coronary heart disease in Chinese Han population

BackgroundPrevious studies in mice and humans have implicated the lipoprotein receptor SRB1 in association with atherosclerosis and lipid levels. In our previous proteomics research, the expression of ITGB2 has differences between epicardial and subcutaneous adipose tissue. However, the association between the reported variants and risk of coronary heart disease (CHD) was not confirmed.\n\nMethodsWe conducted a case-control study consisted of 496 CHD patients and 367 controls. The two groups are adjusted for age, sex, body mass index, diabetes status and the proportion of dyslipidemia. The genotypes and allele frequency of variants rs838880,rs5888,rs5889 in SRB1 and rs235326,rs2070947,rs2070946 in ITGB2 were determined using Sequenom Mass-ARRAY technology.\n\nResultsThe genotypes frequencies of all the six SNPs were consistent with Hardy-Weinberg Equilibrium test. For gene SRB1 rs838880, there was a significant difference in the alleles frequency(p=0.017), genotype frequency(p=0.0028), recessive model (p=0.000672) between CHD group and control group. For gene ITGB2 rs2070947, there was a significant difference in the recessive model (p=0.03). By comparing the clinical and serum metabolic indexes of SNP sites by genotype we find that among three genotypes of SRB1 rs5888,there were significant difference in the level of dyslipidemia history and serum LPA, among three genotypes of ITGB2 rs235236,there were significant difference in the levels of serum HDL,APOA1 and hypertension history, among three genotypes of ITGB2 rs2070947,there were significant difference in the level of serum APOA1,hsCRP.\n\nConclusionsOur findings indicated that SNP rs838880 of gene SRB1 and rs2070947 of gene ITGB2 are associated with the risk of CHD in Chinese han population.

genetics↗

Mapping The Malaria Parasite Drug-Able Genome Using In Vitro Evolution And Chemogenomics

Chemogenetic characterization through in vitro evolution combined with whole genome analysis is a powerful tool to discover novel antimalarial drug targets and identify drug resistance genes. Our comprehensive genome analysis of 262 Plasmodium falciparum parasites treated with 37 diverse compounds reveals how the parasite evolves to evade the action of small molecule growth inhibitors. This detailed data set revealed 159 gene amplifications and 148 nonsynonymous changes in 83 genes which developed during resistance acquisition. Using a new algorithm, we show that gene amplifications contribute to 1/3 of drug resistance acquisition events. In addition to confirming known multidrug resistance mechanisms, we discovered novel multidrug resistance genes. Furthermore, we identified promising new drug target-inhibitor pairs to advance the malaria elimination campaign, including: thymidylate synthase and a benzoquinazolinone, farnesyltransferase and a pyrimidinedione, and a dipeptidylpeptidase and an arylurea. This deep exploration of the P. falciparum resistome and drug-able genome will guide future drug discovery and structural biology efforts, while also advancing our understanding of resistance mechanisms of the deadliest malaria parasite.\n\nOne Sentence SummaryWhole genome sequencing reveals how Plasmodium falciparum evolves resistance to diverse compounds and identifies new antimalarial drug targets.

genomics↗