Adipose-derived regenerative cells (ADRC) will be extracted from lipoaspirate by enzymatic digestion. 10 mL of autologous ADRC suspension injected intramuscularly, close to the site of muscle injury. All patients will receive cell therapy. This is a single arm study with no control.

Fat tissue obtainment:

Subjects will undergo liposuction under local anesthesia. In this procedure, Ringer's solution with the anesthetic lidocaine and vasoconstrictor adrenaline infused into the adipose compartment to minimize blood loss and contamination of the tissue by peripheral blood cells. 15 minutes later a hollow blunt-tipped 3 mm cannula introduced into the subcutaneous space through small (0.5 cm) incision. The cannula attached to syringe and under gentle suction moved through the adipose compartment, mechanically disrupting the fat tissue. Aspirate volume - approximately 150-200 cc. Procedure time - 30 minutes.

ADRC isolation:

Harvested adipose tissue will be processed according to patent pending technology based on enzymatic digestion, washing and concentration of cell pellet in 10.5 ml of normal saline. Obtained ADRC divided into 2 portions. First portion (0.5 mL) used for counting, viability and sterility assessment. The second portion (10 ml) placed into sterile syringe for injection.

Autologous ADRC administration

10 mL of autologous ADRC suspension will be injected intramuscularly, close to the site of muscle injury. 10 to 20 injections (0.5 to 1.0 mL each) will be performed so as to infiltrate the injured muscle.

Inclusion Criteria:

• Patients with critical lower limb ischemia, with resting pain wich can't be adequately managed by opioid analgetics and/or foot ulcers or necrosis, with II-4, III-5 и IV-6 stages of chronic arterial failure according to Rutherford's classification
• Ankle-brachial index less than 0.4 and/or ТСрО2 less than 30 mm Hg
• Patients with lower limbs' arteries lesions revealed by angiography uneffectiveness or impossibility of limb's revascularisation or patient's refusal of the procedure
• Patient is familiar with Participant information sheet
• Patient signed informed consent form

Non-inclusion Criteria:

• Contraindications for local anesthesia or history of allergy for local anesthetics
• Systemic glucocorticoid and/or immunosuppressant therapy
• Any condition that might limit compliance (dementia, mental disorders, narcotic drug or alcohol abuse etc.)
• Participation in other clinical trials (or administration of investigational drugs) during 3 months prior inclusion
• Patients with malignant tumors including postoperative period, patients receiving chemotherapy and/or radiotherapy
• Clinically significant abnormalities in results of laboratory tests
• Patient received anticoagulants at least 12 hours prior the liposuction
• Medical history of heterotopic ossifications
• Patients prescribed for glycoprotein inhibitors treatment

Exclusion Criteria:

• Patient's refusal from the further participation in trial
• Chronic kidney disease IV- V stages (creatinine clearance < 30 mL/min estimated by Cockcroft-Gault formula)
• Confirmed syphilis, HIV, hepatitis B or C infections

Dropout Criteria:

• Indications for the amputation of the limb