Table 1.

Analysis of cell surface marker expression by flow cytometry after transfection (%, $\overline{X}\mathrm{\hspace{0.17em}\hspace{0.17em}}\pm \mathrm{\hspace{0.17em}\hspace{0.17em}}\mathrm{S}\mathrm{D}$).

Group	N	CD29	CD44	CD34	CD45
hBMSC P3	5	98.10 ± 1.10	94.99 ± 1.00	0.32 ± 0.12	1.78 ± 0.44
hPPE-hBMSC	5	99.08 ± 0.55	95.07 ± 2.35	0.43 ± 0.40	1.48 ± 0.45
pBABE-hBMSC	5	98.99 ± 0.59	93.37 ± 2.36	0.57 ± 0.35	1.82 ± 0.49
F value	—	2.368	1.141	0.815	0.796
P value	—	0.136	0.352	0.466	0.474

Cultured hBMSC, pBABE-hBMSC, and hPPE-hBMSC at passage 3 were analyzed for CD 29, 34, 44, and 45 expression using FACS. The lack of CD 34 and 45 expression and presence of CD 29 and 44 expressions indicate a mesenchymal stem cell lineage after transfection. hPPE, human proenkephalin; hBMSC, human bone marrow stem cell; pBABE-hBMSC, the pBABE-hBMSC group; hPPE-hBMSCs, the hPPE-hBMSC group.