Another look


Methodology and good practices to integrate "regenerative medicine in compliance with the regulations.

Dr. Nicola Beneduce, MD Department of plastic and maxillofacial surgery. AP-HP Paris-Est Créteil


INTRODUCTION. PRP - Platelet Rich Plasma

PRP - Platelet Rich Plasma is a blood-derived biological product characterized by a high concentration of growth factors.

  • The Platelet-Rich PlasmaPRP, from which the acronym PRP is derived, is used therapeutically because of its unique ability to stimulate and facilitate tissue regeneration.
  • PRP has long been used in the medical fields of cardiac surgery, oral surgery, orthopedics, gynecology and facial plastic surgery, and continues to develop as a versatile therapy in dermatology.
  • PDGF (Platelet Derived Growth Factor): iIt has mitogenic and angiogenic action with up-regulation of other growth factors, stimulates fibroblasts and osteoblasts, induces cell differentiation and is a catalyst for the effects of growth factors on other cells such as macrophages. It also stimulates chemotaxis and its reticular structure facilitates the diapedesis of macrophages and fibroblasts. 2.
  • THE EGF (epidermal growth factor): It has the ability to induce proliferation and differentiation of mesenchymal and epithelial cells and also promotes angiogenesis. 3.
  • TGF (transforming growth factor): stimulates fibroblasts and pre-osteoblasts, inhibits epithelial and endothelial cells and is an important mediator of extracellular matrix formation. 4.
  • VEGF (Vascular Endothelial Growth Factor): stimulates monocyte migration through the endothelial layers and is one of the most important angiogenic factors. It induces an increase in the permeability of endothelial cells to proteins and other molecules; this permeability leads to the extravasation of fibrinogen and the formation of fibrin, which in turn induces the migration of fibroblasts.
  • FGF (Fibroblasts Growth Factor): They are powerful regulators of cell proliferation and fibroblast differentiation. It plays an important role in normal development and wound repair. It stimulates the proliferation of all cells of mesodermal origin and many cells of neuroectodermal, ectodermal and endodermal origin.
  • These cells include: fibroblasts, endothelial cells, osteocytes. They also play an important role in the formation of new endothelia.
  • Platelets are therefore comparable to cell reservoirs that release numerous growth factors that stimulate the reproduction of stem cells, mesenchymal cells, fibroblasts, osteoblasts and endothelial cells.
  • They also release other types of granules containing ADP, ATP, calcium ions, histamine, serotonin and dopamine that play a complex role in tissue modulation and regeneration.
  • Finally, they still contain lysosomal granules that may secrete various enzymes whose precise role in the healing process is not yet well understood.
  • Over the years, attention to PRI has grown to over 3000 articles in the last 5 years.


There are two different ways to prepare PRP: open-loop and closed-loop.

The open loop iThe use of unapproved kits, using conventional blood collection instruments, exposes the product to a high risk of contamination.

Approved closed-loop kits, on the other hand, eliminate this risk and also make preparation easier and more reliable. Although there is no clear consensus, the recommendation of the European institutions is to use approved closed-loop kits.

The preparation of PRP involves the collection of autologous venous blood (i.e., the patient's own), which is then centrifuged. The patient's blood is drawn, collected and centrifuged at different speeds until it separates into three layers: platelet-poor plasma (PPP), platelet-rich plasma (PRP) and red blood cells (RBC). The material with the highest specific gravity (PRP) will be deposited at the bottom of the tube and removed for use.



Human autologous PRP should be considered a blood product.

In order to better understand the context of the current European rules, it is necessary to differentiate between blood products for topical use and those used in cell therapy, which involve complex bioprocessing techniques for therapeutic cells. All rules have a common goal:

  • ensure the voluntary donation of a blood product;
  • self-sufficiency in blood, blood products and plasma derivatives;
  • ensure the health of donors and recipients;
  • the quality and safety of transfusion medicine procedures and products.


The preparation of autologous platelet concentrates is regulated by article L. 1221-8 of the public health code.

It is also authorized, pursuant to Article L. 1243-2, to withdraw and use autologous blood for therapeutic purposes within the framework of a single medical intervention without being stored or prepared within an organization or establishment.

  • This means that the procedure can be performed not only in a hospital setting, but also in your own practice.

The law therefore limits the use of PRP to treatments with a therapeutic purpose.

  • The prohibition on the use of CPAs for cosmetic purposes was reiterated in a ruling by the Conseil d'Etat dated November 4, 2015.
  • The ANSM recalled in a statement published on January 10, 2018 that the use of APCs is prohibited in France.

It is therefore the objective of the intervention (therapeutic or aesthetic) that determines the applicable regulations.

  • It is therefore up to the physician to determine the right indication. The most frequent and obvious example is certainly the treatment of alopecia.
  • In this case, it is the physician's duty and interest, before proposing a PRP treatment, to make a complete assessment in order to clinically frame the patient in a meticulous way and to certify at the same time the functional character of the proposed treatment.


  • Standardized preparation independent of the operator
  • Low volume of blood required
  • Closed system, no contact with the outside
  • Mechanical separation of PRP after 5 minutes centrifugation using a biologically inert thixotropic gel
  • Reversible anticoagulation with pharmaceutical grade sodium citrate solution at pH 7
  • Fast learning curve and ease of use
  • Operationally and clinically effective process
  • Facilitates and streamlines daily practice
  • Standardized and easily reproducible PRP
    RegenLab's specific gel separation technology ensures minimal variability
  • Platelet recovery > 80 %
  • High quality of the wafers
    Viable and functional platelets
  • Complete plasma recovery
    No loss of plasma growth factors and fibrinogen
  • Leukocyte-poor PRP
    Depletion ~ 96.7 % of pro-inflammatory granulocytes, leaving mainly lymphocytes and monocytes
  • Elimination of almost all red blood cells
    Depletion of ~ 99.7 % in erythrocytes




In the literature, we find many works on the treatment of alopecia with PRP that help us answer patients' questions.

The most common one is certainly whether PRP can increase hair density. The answer is: yes, by 10 to 20 %. PRP slows down hair loss, as well as increases hair thickness.

What we cannot do, however, and what must be clearly explained to our patients, is the creation of new hair follicles.

PRP should not be considered an alternative to hair transplantation, although it is often used as an adjuvant treatment in the postoperative period to maintain the result.

Not all patients with androgenetic alopecia can benefit from PRP treatment, but only those in Norwood stage I - II or III, due to the ineffectiveness of the product when injected into a hairless area.

The technique: 

  • It consists in inoculating in a subdermal plane, where the hair bulb is located, 0.1 ml per cm2.
  • Regarding the choice of material,
    • we prefer to use a 1 ml syringe, which allows us greater precision;
    • for the needle, we follow the theory of "the smaller the better", thus opting for a 32G/ 34G needle.
  • The goal, given that between 100 and 200 injections are performed per treatment, is to ensure that the patient suffers as little pain as possible and that bleeding is minimized.
  • Some physicians prefer the use of the gun, which allows for a faster and more precise inoculation.
  • This is because the gun is set to a fixed depth at which the device releases the PRP.

To prevent hair loss, it is recommended to inject at a depth of 4 mm, in order to reach the hair bulbs directly. In cases where the patient has a bad scalp, a double injection plane is used instead, deep (4 mm) and shallower (2 mm). Initially, one session per month is planned for three months, followed by a maintenance treatment every three months.


A less common but very popular indication, especially for women, is the treatment of dark circles.

  • In this case, 3 sessions of PRP are performed at 1 month intervals by injecting 1 ml on each side in the dermal and subdermal plane.
  • The results are maintained by two procedures each year.

The results are satisfactory and without risk. A combination of peeling or laser treatment may be indicated.


Excellent results have also been obtained in the treatment of keloid scars, refractory to corticosteroid treatment and surgery, by combining PRP and surgery.


Complications associated with this type of treatment, if the proper injection techniques are used, are extremely rare.

More common are side effects such as pain, erythema, swelling and, in the case of scalp treatment, headaches, for which scalp massages twice a day in the week following treatment should be planned.

RegenKit® - Surgery

With this kit, we can combine autologous thrombin with PRP. By combining 1 ml of thrombin with 10 ml of PRP, a gel product is obtained that is useful in many applications.

Indeed, it has a role of biological dressing with an indication of use in patients with delayed healing, or to increase the probability of taking a skin graft.

By some surgeons, it has been proposed and used as a filler to treat dark circles, while exploiting its regenerative and filling capabilities, being an extremely soft and malleable product.

Its composition also allows it to be used as a surgical glue, a trick long known by our digestive surgeon colleagues, who use it widely in digestive anastomoses.


Cellular Matrix

Cellular Matrix® tubes allow the preparation of of autologous platelet-rich plasma (RegenPRP®) partner to a non-crosslinked Hyaluronic Acid (HA) in a closed system.

Cellular Matrix® technology combines the synergistic effects of RegenPRP® and Hyaluronic Acid (HA).

Contains 2 ml of 20 mg/ml concentrated non-cross-linked HA (40 mg in total).  HA is produced by bacterial fermentation (free of animal proteins).

The presence of a separating gel inside ensures that the hyaluronic acid and PRP quota is not contaminated, so that the injected product is as pure as possible.


An excellent product for facial mesotherapy, it can be applied with the topping technique or with a dermaroller.

  • Also in this case, it is important to remember the need to frame the patient from a clinical point of view in order to establish the right indication, such as the treatment of acne sequelae.

This kit has a wide range of use in the gynecological field, which allows it to be used in the office thanks to its approval.

Two pathological conditions benefit from treatment with PRP enriched with hyaluronic acid: 

1. Postmenopausal genitourinary syndrome

2. Vulvovaginal atrophy in women with a history of breast cancer:

  • Indeed, approximately 55-75 % of women with breast cancer have been found to have vulvovaginal atrophy related to estrogen deficiency and chemotherapy treatment.
  • Due to these biological causes and psychological distress related to body image, a decrease in the quality of sexual life has been recorded in these patients.
  • It has also been observed that more than 30 % of patients do not complete hormonal treatment, which is often due to the side effects of the treatment itself, thus putting themselves at a higher risk of recurrence.
  • The procedure involves the topical application of an anesthetic gel and the administration of Kalynox to make the procedure as painless as possible.

3. Episiotomy scars are another indication in the gynecological field with a clear improvement in terms of aesthetics and function.


Aesthetic health based on scientific evidence

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