Macrophage Paracrine Signalling Differentially Affects Fibroblast-Induced Collagenous Tissue Remodelling

Factors secreted by M1 macrophages resulted in reduced tissue compaction compared to M2a/M2c macrophages in an in vitro model of tissue remodelling, suggesting a diminished capacity for fibroblasts to remodel the extracellular matrix. Importantly, factors to polarize macrophages and serum are regarded as confounding factors in studying the effect of paracrine signalling by macrophages on tissue remodelling.