Extended Data Fig. 8: Local release of BA-modified IgG.
a) Representative confocal images illustrating fluorescence recovery and photobleaching (FRAP) experiments. Fluorescence recovery was quantified by monitoring the return of fluorescence signal in the bleached region over 10 min using a 640 nm excitation laser. The white scale bar in the bottom left represents 40 μm. b) FRAP data (n=3 for each group) was fit to a first-order exponential equation to extract the FRAP half-time (t1/2) and the mobile fraction (Mf). Loading BA-modified IgG in SABER hydrogels reduced the Mf and increased the t1/2, suggesting that the rate of payload diffusion in these samples is slower. We observed minimal differences between IgG labeled with 11.4 BAs per antibody (IgG high) and 2.4 BAs per antibody (IgG low), demonstrating that the degree of labeling may not play a large role in controlling the rate of diffusion. All data were well-modeled by the first-order exponential equation and had R2 values above 0.95 except for SHA-E2 + IgG high (denoted with an asterisk), which was poorly fit by this model and thus extracted parameters may not accurately describe the data. c) In vivo release data of IgG with low and high degrees of BA modeling was modeled with a first-order exponential equation to determine the half-life (t1/2) and burst release from the site of injection. All SABER hydrogels had a moderate burst release of 20% but significantly extended the t1/2 of the antibody at the injection site. All fits adequately modeled the data (R2 > 0.95). All numerical data in this figure is presented as the mean value of four replicates ± 95% confidence interval.
