TGF-β and TNF-α Signaling Crosstalk in Human Coronary Artery Cells

Transforming growth factor-β1 (TGF-β1) and tumor necrosis factor-α (TNF-α) are central regulators of vascular inflammation and remodeling in coronary artery disease. However, their cell-type-specific and context-dependent effects in primary human coronary artery endothelial cells (ECs) and vascular smooth muscle cells (VSMCs) remain incompletely defined. Primary human coronary artery endothelial cells (pHCAECs) and smooth muscle cells (pHCASMCs) were stimulated with TGF-β1 (10 ng/mL), TNF-α (100 ng/mL), or their combination. Canonical SMAD2/3 activation, Krüppel-like factor 11 (KLF11) expression, cytoskeletal and junctional remodeling, vascular cell adhesion molecule-1 (VCAM-1) expression, migration dynamics (wound healing and confluent assays), and endothelial tube formation were assessed using immunofluorescence microscopy, live-cell imaging, and quantitative trajectory analysis. Both cytokines were associated with increased nuclear pSMAD2/3 signal in ECs and VSMCs, consistent with functional interplay between inflammatory and TGF-β-related signaling pathways. In pHCAECs, TNF-α robustly induced VCAM-1 functional expression and disrupted VE-cadherin continuity, whereas TGF-β1 primarily promoted cytoskeletal remodeling without strong inflammatory activation. TGF-β1 increased endothelial migration velocity and accumulated distance. In contrast, TNF-α preferentially enhanced Euclidean displacement and directional persistence, shifting the migratory pattern toward more directed movement most evident under combined TGF-β1 + TNF-α stimulation. Notably, TGF-β1 significantly reduced endothelial tube formation, indicating impaired network organization rather than proangiogenic activity. In pHCASMCs, TGF-β1 enhanced migratory activity, particularly in confluent monolayers, whereas TNF-α enhanced directional displacement. KLF11 was induced by TGF-β1 in both pHCAECs and pHCASMCs. In pHCAECs, TNF-α also increased KLF11 and co-stimulation promoted nuclear enrichment, whereas in pHCASMCs TNF-α alone was not effective and combined treatment amplified the TGF-β1 response, supporting cell-type-specific integration of inflammatory and TGF-β-dependent signals. TGF-β1 and TNF-α differentially regulate the inflammatory activation and migration of primary human coronary vascular cells in a cell-type- and structural-context-dependent manner. TGF-β1 enhances migratory force generation, whereas TNF-α reinforces directional polarization, and their integration determines effective vascular repair dynamics. Canonical SMAD2/3 activation does not uniformly predict functional outcome, and KLF11 was identified as a context-sensitive transcription-associated factor showing differential nuclear localization in response to cytokine stimulation, representing a hypothesis-generating observation for future mechanistic studies.