Plasma growth factors are proteins found in tissues and are responsible for the repair of damaged tissue, in diseases such as tendinopathies, meniscal lesions or corneal and vascular ulcers, or alopecia, among others.
Plasma growth factors: what are they?
Within what is known as Regenerative Medicine, growth factors are proteins of extraordinary diffusion through the tissues, either of leukocyte or platelet origin, commonly known as “Platelet-rich plasma”. This technique has the local or systemic function, depending on the form of clinical application, to act on the cellular reproductive cycle. In this way, it induces their proliferation, as well as the differentiation of cells in various stages of maturation towards mature elements, in addition to manufacturing new blood vessels, being able to repair ischemic or malfunctioning tissues due to a defect in cellular oxygenation.
How plasma growth factors are obtained
Nowadays, growth factors are found in granules called alpha, within the cytoplasm of platelets, and in other similar granules in leukocytes, especially in their mononuclear fraction.
They are obtained through a systematic process of centrifugation of whole blood, which allows finally obtaining a concentrate rich in one cell type or another. Currently, the scientific literature recognizes 6 procedures for obtaining plasma growth factors. One of them, called Alcaraz, Oliver et al 2014, was designed by the author of this article. The technique has been recognized by the European Society of Hematology, given its scientific and technical rigor, and has been widely reproduced throughout the world for being the one that produces the highest platelet and leukocyte yield. It was recently presented in the United States at a conference on experts in therapeutic procedures applied to certain clinical cases, receiving the prize for the best oral communication.
In the case of a plasma rich in platelet growth factors, the scientific consensus considers it to be of high quality when it contains platelet values above 1,000,000/mm3. As for plasma rich in leukocyte growth factors, it is considered effective when the leukocyte content exceeds 20,000/mm3, 80% of which must be mononuclear cellularity.
Growth factors of either origin can be activated either with 1% calcium gluconate or with bovine thrombin, to activate them when administered locally.
Differences between the growth factor procurement technique and the stem cell procurement technique
Growth factor and stem cell procurement techniques are not the same. The techniques for obtaining stem cells of different origin are fundamentally experimental, which are developed, for the most part, in the context of clinical trials and under rigorous sterile conditions in what are called clean rooms, of which there are very few in Spain, especially in third level hospitals.
What is often advertised as plasma enriched with stem cells is not true either. In peripheral blood the quantity of circulating stem cells is practically negligible and complex cell mobilization procedures are necessary to increase their number in the bloodstream to levels useful for treatment, such as hematopoietic progenitor transplantation.
Obtaining growth factors must also be carried out under extremely aseptic conditions, either in a laminar flow hood if an open technique is used, or in a closed system using specific kits with the correct European Economic Community certification.
Who can undergo treatment with plasma growth factors?
To ensure the suitability of this procedure, an exhaustive clinical history must be taken, with a systematic anamnesis and physical examination, in addition to a complete serological, biochemical and hematological analytical control, after which the hematology specialist will consider whether or not the patient is suitable for treatment.
There are a series of contraindications for the use of this therapy:
– pregnant patients
– concomitant treatment with antiplatelet or anticoagulant drugs.
– patients with hemopathies or coagulopathies
– patients with active infectious or oncological processes.
Fields of application of growth factors
New clinical applications for this type of therapy are appearing every day. Those specialties where there is more clinical evidence for its use are Traumatology and Dentistry.
Uses of plasma growth factors and results obtained
This technique is increasingly used for a multitude of clinical applications. Of these, the most common where there is the most scientific evidence is in Traumatology, for the treatment of incipient arthropathies, tendinopathies or meniscopathies, as well as in Dentistry, for the repair of the dental alveolar bed.
Other emerging fields where it is beginning to be used, although scientific studies in the form of well-structured clinical trials are still needed, are General Surgery, for the treatment of ulcers in diabetic patients or vascular ulcers, Ophthalmology, for the repair of corneal ulcers, and Dermatology, for the treatment of certain types of alopecia.
The results obtained, depending on the assigned clinical application, are intended to improve cellular oxidative functionality in the administered tissue, repairing the damaged ischemic tissue in a secondary way.
Side effects of plasma growth factors
Like any medical treatment, it is not exempt from producing side effects, especially of allergic origin (fever or skin rash) or mechanical, such as a small hematoma at the puncture or administration site.
However, as it is an autologous concentrate that comes from the patient himself, there are no problems of rejection.
How to ensure the quality of growth factors
This treatment has been considered a drug since 2013 and, since June 2015, there has been an obligatory registration at the Spanish Medicines Agency of those centers producing plasma growth. These must specify the responsible physician, as well as the clinical application where it is used and the procedure for obtaining it.