Bone marrow stem cell autologous transplant could become a promising new frontier in the hand of vascular specialists for the treatment of peripheral artery occlusive disease.
Since it is a minimally invasive, reproducible, cheap and apparently safe procedure, it could be the milestone of a completely new approach toward end-stage critical limb ischaemia before the need of amputation, a study conducted in Italy concluded.
“Whether this method will be useful, reliable and widely acceptable in clinical practice still remains to be confirmed by larger series and longer follow-up, but preliminary results are quite satisfactory. I hope that in the future we will be able to further improve our results by labelling stem cells with metallic nanoparticles and targeting them to the affected limb with magnetic fields,” said Alessandro Schiavetta, Departament of Vascular Surgery, Santa Corona Hospital, Pietra Ligure, Italy, principal investigator of the study ‘New frontiers in the endovascular treatment of critical limb ischaemia: the autogenous transplant of bone marrow stem cells’.
Bone marrow stem cells keep a high proliferative potential and can be committed to different tissues and cellular lines. Among haematopoietic stem cells, endothelial progenitor cells are able to repair endothelial damage and promote angiogenesis and vasculogenesis. The bone marrow stem cells collection and injection in the affected leg may improve peripheral blood supply by generating angiogenesis processes.
The multicentre, phase II, single-arm study started in October 2008 at Naples University (Prof Vincenzo Sica) and S Corona Hospital (Pietra Ligure, Savona, Italy). The study will enrol 38 patients with very short walking distance, rest Pain or peripheral ischaemic lesions, where traditional or endovascular therapies have failed or are not indicated, between October 2008 and October 2010. Comorbidities comprehend in many cases diabetes, hypertension, and myocardial ischaemia.
Procedures are performed in operation room. Bone marrow stem cells (100cc) are collected through posterior iliac crest puncture, filtered through a dedicated kit and then reinfused in common femoral artery in 40 minutes, with a 4F introducer. A second transplant is performed 45 days later. All patients are given oral arginine for four months after transplant, and all patients undergo basal duplex scan, contrast-enhanced magnetic resonance or computed tomography scan and/or digital subtraction angioplasty and transcutaneous oximetry with scheduled follow-up at three, six and 12 months.
To date, the group has performed 38 procedures in 19 legs – 18 patients (mean age 70 years, range 45–81), without any complications. One patient with previous coronary artery bypass graft developed a non-fatal myocardial infarction four months after the procedure. During follow-up (mean 150 days, range 42–381) of the first 13 patients treated, the investigators noted a 64% of patients responding to the treatment, with measurable increase of peripheral TcpO2 in 77% of cases (ten of thirteen), healing of ischaemic lesions and a noticeable increase of walking distance beginning three months after transplant.
Co-authors of the study are Stefano Pagliari, Department of Vascular Surgery, Gennaro Marino, Department of Immuno-haematology and Blood Transfusion Medicine, and Lorella Lanza, Department of Histology and Pathological Anatomy, Santa Corona Hospital.