Treatment of Knee Osteoarthritis With Autologous Mesenchymal Stromal Cell Product (RegStem)

Inclusion Criteria: 1. Subjects who understand and sign the informed consent form for this study 2. Grade 2\~3 osteoarthritis according to the Kellgren-Lawrence grading scale with one-month X-ray 3. Age is 50\~75 years old 4. Postmenopausal women 5. VAS scores in 50 to 90 mm Exclusion Criteria: 1. Abnormal of liver and kidney: GOT and GPT \> 100 IU/L, BUN \>22 mg/dl and creatinine \> 1.2 mg/dl. 2. Positive serology for HIV, HTLV-1/2 and syphilis 3. Women who are pregnant or breast feeding 4. Serious pre-existing medical conditions: coagulation disorders, cardiovascular diseases (arrhythmias, myocardial infarction and surgery), renal diseases (chronic renal failure), liver diseases (cirrhosis), diabetes mellitus type I, cancer history. 5. Other joint diseases: knee deformity (knee varus greater than 10 degree or valgus greater than 20 degree), rheumatic arthritis, gouty arthritis, septic arthritis, serious meniscal tear, other autoimmune arthritis. 6. Skin inflammatory of knee 7. Knee pain caused by referred pain from spine disease or hip joint disease. Knee pain combined with pain from spine disease or hip disease. 8. Immunosuppressive state 9. Subjects who were injected with hyaluronic acid and PRP in the past 6 months 10. Body mass index (BMI) greater than 30 11. Have a history of allergic reaction of any medication 12. Participation in another clinical trial or treatment within 3 months 13. Other pathologic conditions or circumstances that difficult participation in this study according to PI's evaluations