A Safety and Efficacy Study of Autologous Bone Marrow Derived Mesenchymal Stem Cells in Critical Limb Ischemia

Inclusion Criteria: * Age from 20 to 80 years * Patients with resting pain or ulceration of limb (Rutherford's class: II-4, III-5 or III-6) * Ankle Brachial Pressure Index (ABPI) ≤ 0.6 or TCPO2 ≤ 60mmHg in the foot * Patients who were unsuitability for percutaneous transluminal angioplasty or a bypass operation * Patients who are not expected other treatments for at least 6 months * Patients who can agree to participate in the clinical trial by oneself or by one's legal representative * Patients who can conduct the clinical trial according to the protocol Exclusion Criteria: * Buerger's disease * History of hematologic disease * Patients who are at risk of embolism due to atrial fibrillation * Primary hematologic disease, including hypercoagulable states * Entrapment syndrome * Patients with osteomyelitis * Patients whose blood serum AST(Aspartate transaminase)/ALT(Alanine Transaminase) rates are more than three times the normal maximum rate, or whose creatinine rates are more than 1.5 times the normal maximum rate * Patients with history of anaphylaxis to gentamicin * Patients with hypersensitivity of bovine-derived ingredients * Patients with chronic heart failure, Glomerular disease and Obstructive pulmonary disease * Patients with Stroke or transient ischemic attack within 6 months prior to registration * Patients tested positive for HIV(Human Immunodeficiency Virus), HCV(Hepatitis C Virus), HBV(Hepatitis B Virus) and Syphilis * Patients with history of aorta and artery bypass operation, or angioplasty within 2 months recently * Patients in need of a immediate amputation and have a potentially life-threatening complications of critical ischemia * Patients with history of cell therapy * Type I diabetes * Uncontrolled diabetes mellitus (HgbA1C\>8%) * Uncontrolled hypertension * Has a medical record of solid cancer, or diagnosed with solid cancer and currently receiving cancer treatment * Positive of tumor markers test(AFP((Alpha fetoprotein), CEA(Carcinoembryonic antigen), CA15-3(Cancer antigen 15-3 for breast cancer) and PSA(Prostate-specific antigen), or have received a diagnosis of cancer based on National cancer screening program * Pregnancy, possible candidate for pregnancy or lactating women * Infectious disease * Administrating of immunosuppressive agents, corticosteroid formulation and cell toxicity formulation, or requiring administration of the test period * Patients already enrolled in another clinical trials or completed within 3 months * Patients who cannot adapt to the protocol and follow-up observation * Patients who has experienced drug abuse for the past 1 year * Patients with any disease or condition which the investigator fell would interfere with trial or the safety of the subject