Table 2.

Myogenic Differentiation of Human Muscle Progenitor Cells Cultured on Muscle-Extracellular Matrix-Hyaluronic Acid-Heparin Gels, Compared to Those on Other Gels

	Blank	Matrix gel	HA-HP gel	Muscle-ECM-HA-HP gel	Kidney-ECM-HA-HP gel	Liver-ECM-HA-HP gel
Under phase contrast microscopya
Myofibrils	+	+	2+	3+	3+	3+
Myotubes	+	2+	3+	4+	3+	3+
Immunoflurorence stainingb
Myf5	2+	1+	1+	3+	3+	3+
MyD	1+	2+	2+	4+	3+	2+
Desmin	2+	1+	1+	4+	2+	3+
Myosin	1+	2+	2+	3+	2+	2+

The percentage of positive cells was scored as follows: 0 = no staining; 1+ = 0–25%; 2+ = 26–50%; 3+ = 51–75%; and 4+ = 75% above assessed immunofluorescent staining, triple samples. Both stained cells per section and the percentage of the area stained compared to the total area were calculated by computerized image analysis.

^aMyogenesis was evaluated by myofusion index in parent cells and thickness of myotubes 72 h after induced differentiation under phase contrast microscope.

^bThe numbers of the nuclear expressing Myf5 and MyD per mm and the numbers of the cells expressing desmin and myosin were determined under immnuoflurorence microscope.

ECM, extracellular matrix; HA, hyaluronic acid; HP, heparin.