Project Title


Application of Leukocyte- and Platelet-Rich Fibrin as a Stimulator of Angiogenesis in Patients Undergoing Revascularization Due to Critical Limb Ischemia

Acronym


ARISTOTLE

Agreement Number


Agreement No. 2020/ABM/01/00078

Funding Institution

Medical Research Agency

Principal Investigator

Prof. Zbigniew Gałązka, MD, PhD

Total Funding Awarded 

8,676,067.60 PLN

Project Objective

Obliterative atherosclerosis of the lower limb arteries is a commonly occurring civilization-related disease within the group of cardiovascular disorders. It is associated with high morbidity, elevated mortality rates, and a significant reduction in patients' quality of life. It is estimated that approximately 202 million people worldwide are currently affected by this condition, and in many cases, disease progression may lead to limb amputation. Reported prevalence rates vary in the literature from 4.3% to 57%, depending on diagnostic criteria, age, and risk factors in specific population groups. Advanced age, male gender, coexisting diabetes, and tobacco use are significantly associated with increased risk of developing the disease.

Currently, the first-line treatment includes endovascular procedures or surgical bypass grafting. Although the technical success of these treatments is relatively high, long-term outcomes regarding limb salvage and limb-loss-free survival remain unsatisfactory. Previous attempts to use mesenchymal stem cell therapy have not significantly improved limb salvage rates; however, they were applied only in patients with no remaining options for revascularization.

The formation of a new vascular bed—angiogenesis—is a complex and multifactorial process. Despite the ability to culture various stem cells responsible for angiogenesis—including endothelial progenitor cells (EPCs), hemangiopericytes (HPCs), and mesenchymal stem cells (MSCs)—the initiation of a consistent and predictable angiogenic response in critically ischemic tissues has not been achieved.

Potential reasons for this failure include:

1. implantation of single-lineage cells despite the complex and not fully understood mechanisms of cellular and protein interactions during angiogenesis,
2. donor cell anergy resulting from chronic inflammation in generalized atherosclerosis,
3. implantation of cells that, due to lack of access to blood and metabolic substrates, die before initiating angiogenesis,
4. implantation of allogeneic cells, which are rapidly rejected by the host, preventing any therapeutic effect.

Meanwhile, a number of recent experimental studies have demonstrated the strong angiogenic potential of leukocyte- and platelet-rich fibrin (L-PRF) in initiating the development of new vascular networks. L-PRF is an autologous medicinal product, obtained directly from the patient’s blood by centrifuging platelets and leukocytes to separate them from red blood cells and suspending them in a fibrin gel. This autologous product has properties that induce angiogenesis, accelerate wound healing, and modulate immune responses.

It is expected that, in addition to restoring temporary vessel patency, this approach will significantly accelerate secondary angiogenesis in the ischemic limb and reduce the perivascular inflammatory response triggered by the revascularization procedure itself. We hypothesize that this will significantly prolong the asymptomatic or minimally symptomatic phase of the disease, which will in turn result in higher limb salvage rates and potentially lower mortality in this patient group.

The aim of the study is to develop novel interventional strategies for the treatment of critical lower limb ischemia using the L-PRF medicinal product..