Journal: bioRxiv
Article Title: The N-terminal region of malaria vaccine candidate Plasmodium falciparum asparagine-rich merozoite antigen is immunodominant and targeted by polyreactive antibodies
doi: 10.64898/2025.12.11.693633
Figure Lengend Snippet: A) Plasma samples were obtained from P. falciparum -unexposed individuals living in the U.S. who were convalescent COVID-19 patients (n = 7), healthy blood donors (n = 8), systemic lupus erythematosus (SLE) patients (n = 10), or rheumatoid arthritis (RA) patients (n = 8). In all plots, the horizontal dashed line indicates the cut-off for reactivity to PfARMA (MFI = 2.6 × 10 3 ), which equals the average MFI + three standard deviations of reactivity to the other six merozoite antigens among samples from non-autoimmune donors (convalescent COVID-19 patients and healthy blood donors). Differences in reactivity to the various merozoite antigens were tested for statistical significance using a Kruskal-Wallis test, followed by comparisons between PfARMA and all other antigens using Dunn’s post-hoc test, which reports P values that have been corrected for multiple comparisons (n = 6). ** P < 0.01; *** P < 0.001. B) Dose-dependent reactivity of IgG purified from plasma of a P. falciparum -naïve U.S. donor with high anti-PfARMA IgG reactivity to PfMSP1, full-length PfARMA, and fragments of PfARMA, as measured by ELISA. IDR, intrinsically disordered region; FD, folded domain. C) Total plasma IgG concentration plotted against PfARMA IgG reactivity for P. falciparum -naïve individuals and P. falciparum -exposed individuals. The line shows the best-fit using simple linear regression, with 95% confidence intervals. D) Reactivity of recombinant IgG1, IgG2, IgG3, and IgG4 with specificity for a different P. falciparum antigen to PfARMA and PfMSP1.
Article Snippet: The plasmid encoding full-length PfARMA (PF3D7_1136200-bio, Addgene #47730) was modified to introduce a 6× His tag at the C-terminus.
Techniques: Clinical Proteomics, Purification, Enzyme-linked Immunosorbent Assay, Concentration Assay, Recombinant