Modeling of the Interaction of Plasma-Polymerized Pyrrole with Immunoglobulin M (IgM) by Biocomputational Tools

When entering the bloodstream, any exogenous biomaterial is covered by proteins, forming a coating known as protein crown. The opsonization of these biomaterials depends on the formation of the protein crown, within which immunoglobulin M (IgM) is the first antibody expressed during the primary immune response. It has been reported that plasma-polymerized pyrrole (PPPy)-coated biomaterials promote cell adhesion due to molecular interactions established between extracellular matrix proteins and amino groups (NH2) present on the PPPy surface. In this project, we model the interaction of a PPPy structure with a binding site of an IgM model through computational studies such as molecular docking, molecular dynamics, and binding energy. These studies allowed us to conclude that the binding between IgM and PPPy is favorable and driven by electrostatic interactions. Our results suggest that the immune system will be able to recognize PPPy-coated biomaterials, possibly unleashing an opsonic response. Our results should be considered in the design of PPPy-coated scaffolds for use in tissue engineering.