enzyme linked immunosorbent assay elisa kit  (Cusabio)

Journal: Frontiers in Immunology

Article Title: R21/Matrix-M malaria vaccine drives diverse immune responses in pre-exposed adults: insights from a phase IIb controlled human malaria infection trial

doi: 10.3389/fimmu.2025.1620365

Figure Lengend Snippet: Assessment of complement fixation activity and IgG avidity post-R21/Matrix-M vaccination and sporozoite challenge. Semi-immune adults vaccinated with R21/Matrix-M were tested for C1q fixation by NANP and C-terminal antigens ( A and B respectively). Individual and median [IQR] OD 450nm responses are shown. The positivity cutoff was the mean plus three standard deviations of day 0 (horizontal dashed line). The avidity index was determined as the molar concentration of NaSCN required to reduce OD405 to 50% of the value observed in the absence of NaSCN. (C) Avidity to full-length R21, (D) avidity to NANP, and (E) avidity to the C-terminus. Samples with negative antigen-specific total IgG responses by ELISA or insufficient antibody levels for avidity testing at a given time point were excluded from the analysis. Individual avidity responses are displayed alongside the group median and ±95% CI to illustrate variability and overall trends in avidity over time. The Kruskal-Wallis non-parametric test with Dunn’s multiple comparisons was used to assess differences between time points. The challenge day is represented by the red dashed vertical line. *P < 0.05.

Article Snippet: Plates were washed and 40μl of recombinant human complement C1q (Calbiochem) diluted to 10 μg/ml in casein was added and incubated for 30 min at 37°C.

Techniques: Activity Assay, Concentration Assay, Enzyme-linked Immunosorbent Assay