Biomimetic analyses of interactions between macrophages and palmar fascia myofibroblasts derived from Dupuytren's disease reveal distinct inflammatory cytokine responses

Dupuytren's disease (DD) is a common and heritable fibrosis of the hand. It is characterized by the shortening and thickening of the palmar fascia into myofibroblastic nodules that can progress to palmar-digital contractures and permanent loss of dexterity. Molecular analyses of DD tissues and the presence of inflammatory cell infiltrates suggest a pathogenesis initiated by a proinflammatory fascial milieu that promotes myofibroblast activation and palmar fascia contractures. However, the relative contributions of vascular and/or tissue derived immune system cells and cytokine-sensitive stromal myofibroblasts to the development of this proinflammatory microenvironment are poorly understood. To gain insights into this process, we have developed and tested a collagen-based 3D tissue biomimetic co-culture system to assess paracrine interactions between THP-1-derived pro-inflammatory macrophages and primary human palmar fascia myofibroblasts (PFMs). We observed significant and reproducible impacts of collagen-adherent macrophage and PFM co-cultures on the cytokine gene expression profiles of these cells compared to their respective monocultures, and significant changes to the resulting cytokine milieu in their shared culture media, notably TNF and IL-6. Our findings are consistent with central roles for PFMs in cytokine production and immunoregulation of the pro-inflammatory milieu hypothesized to promote DD development.