Table 5.

The differences in transforming growth factor-β and (myo)fibroblasts in normal, hypertrophic, and keloid scars

Factors	Normal scar	Hypertrophic scar	Keloid scar
TGF-β	↑TGF-β1	↑↑TGF-β1	↑↑TGF-β1
	↓TGF-β3/TGF-β1	↑TGF-β2	↑↑TGF-β2
		↓↓TGF-β3	↓↓TGF-β3
		↓↓TGF-β3/TGF-β1	↓↓TGF-β3/TGF-β1
Fibroblasts	↑Cell number	↑↑Cell number	↑↑Collagen I
		↑↑α-SMA	↑α-SMA
		↑↑Proliferation	↑↑Proliferation
		↓↓Apoptosis
		↑TGF-β1
		↑↑Collagen I
Myofibroblasts	Absent	Present	Absent
MMP/TIMP activity	↑MMP-1, 2 and 9	↓MMP-1, 2 and 9	↑↑MMP-2
	↓TIMP-1	↑TIMP-1	↑TIMP-1

TGF, transforming growth factor; SMA, smooth muscle actin; ↑increase; ↓decrease.