posted on 2021-11-12, 18:36authored byEmily
B. Lurier, Victoria A. Nash, Hannah S. Abee, Tamar B. Wissing, Carlijn V.C. Bouten, Anthal I.P.M. Smits, Kara L. Spiller
Biotin–avidin
interactions have been explored for decades
as a technique to functionalize biomaterials, as well as for in vivo targeting, but whether changes in these interactions
can be leveraged for immunomodulation remain unknown. The goal of
this study was to investigate how biotin density and avidin variant
can be used to deliver the immunomodulatory cytokine, interleukin
4 (IL4), from a porous gelatin scaffold, Gelfoam, to primary human
macrophages in vitro. Here, we demonstrate that the
degree of scaffold biotinylation controlled the binding of two different
avidin variants, streptavidin and CaptAvidin. Biotinylated scaffolds
were also loaded with streptavidin and biotinylated IL4 under flow,
suggesting a potential use for targeting this biomaterial in vivo. While biotin–avidin interactions did not
appear to influence the protein release in this system, increasing
degrees of biotinylation did lead to increased M2-like polarization
of primary human macrophages over time in vitro,
highlighting the capability to leverage biotin–avidin interactions
to modulate the macrophage phenotype. These results demonstrate a
versatile and modular strategy to impart immunomodulatory activity
to biomaterials.