Autologous adipose-derived regenerative cells (ADRC) extracted using Celution 800/CRS System (Cytori Therapeutics Inc) from a portion of the fat harvested from the patient's front abdominal wall. ADRC will be administered one-time intraarticularly. This is a single arm study with no control. All patients receive cell therapy.

Patients with verified diagnosis knee joint osteoarthritis (degenerative damage of knee articular cartilage) will undergo knee arthroscopic debridement. 28 days later patients will will undergo liposuction from front abdominal wall under local anesthesia. After that autologous ADRC will be extracted using Celution 800/CRS System (Cytori Therapeutics Inc) from harvested adipose tissue. Extracted ADRC will be administered one-time intraarticularly.

Inclusion Criteria:

• Pain in the knee joint during more than a half day assessed by VAS (score more than 40 mm)
• At least three of the following 6 criteria: 50 years of age or older, stiffness lasting less than 30 minutes, crepitus, bony tenderness, bony enlargement, no warmth to the touch
• Patient is able to walk without assistance
• Patient is familiar with Participant information sheet
• Patient signed informed consent form

Non-inclusion Criteria:

• Medical history of endoprosthetic knee replacement
• Medical history of lower extremity osteotomy
• Medical history of knee surgery (including arthroscopy) during preceding 1 year prior to enrollment
• Medical history of intraarticular injections during preceding 6 months prior to enrollment
• Secondary osteoarthritis of the knee joint: posttraumatic osteoarthritis (developed after clinically significant injury), intra-articular fractures, clinically significant varus or valgus deformities of lower limbs, septic arthritis, joint's inflammatory disorders, gout, advanced chondrocalcinosis, Paget's disease, ochronosis, acromegaly, hemochromatosis, Wilson's disease, primary synovial osteochondromatosis, osteonecrosis, hemophilia
• Patients prescribed for immunosuppressive treatment
• Medical history of systemic autoimmune and inflammatory diseases
• Significant weight loss (> 10% of body weight in the previous year) of unknown etiology
• Medical history of venous thromboembolism or estimated high risk of venous thromboembolism
• Patients prescribed for systemic corticosteroids or other medications treatment with proven impact on bone or cartilage tissue metabolism
• Clinically significant abnormalities in results of laboratory tests
• Any conditions limiting compliance (dementia, neuropsychiatric disease, drug and 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.
• Patient's activated partial thromboplastin time exceeds normal levels more than 1,8 times
• Patients prescribed for anticoagulants treatment or patient received anticoagulants at least one hour prior lipoaspiration
• Medical history of heterotopic ossifications
• Patients prescribed for glycoprotein inhibitors treatment

Exclusion Criteria:

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

Dropout Criteria:

• Pregnancy