Stromal Vascular Fraction and Platelet-rich Plasma injectable to promote dermal wound healing.

Already 1980*s, the clinical observation has been made that adipose tissue
transfer, also known as fat grafting, lipografting or lipofilling, can improve
skin quality and reduce scarring. Since then, many case reports have described
the seemingly beneficial effect of lipofilling on scar appearance. Also, in
several retrospective and prospective clinical trials it has been investigated
if scarring is reduced after lipofilling and/or if this is superior over
placebo treatment.

In controlled and reproducible setting of different animal models, light has
been shed on the mechanism behind the scar appearance improving and pain
reducing properties of lipografting. In animal models, after radiation,
radiation dermatitis can develop, which eventually can give rise to fibrotic
skin, with epidermal thickening and irregular collagen deposition in the
dermis. In clinical studies on lipofilling as an anti-scarring treatment,
outcome is measured either by improvement of scar appearance, or in case of
painful scars, by decrease in pain. The effectiveness of lipofilling for
improvement of scar appearance has been investigated in fourteen case reports
or clinical trials. Overall, all fourteen case reports or clinical trials
report amelioration of scar appearance after lipofilling. Efficacy of
lipofilling as means for pain reduction, was investigated in seven case reports
or studies. Overall, all seven studies report a reduction of pain after
treatment of painful scars with lipofilling.

We are particularly interested in the Stromal Vascular Fraction (SVF)
injectables, which contains adipose tissue derived stem cells (ASCs). ASCs are
mesenchymal stem cells from adipose tissue, which can be easily isolated from
lipoaspirate, where they probably are adjacent as pericytes or periadventitial
cells to little blood vessels. In animal wound healing models, where ASCs were
used to speed up wound healing (25-28) it was observed that ASCs improved the
wound healing rate and smaller fibrotic areas remained after wound healing.
Furthermore, the quality of the epidermis increased, and the gene expression of
the pro-fibrotic markers **-smooth muscle actin* and *transforming growth
factor-*1* decreased while the gene expression of anti-fibrotic fibroblast
growth factor and pro-angiogenic vascular endothelial growth factor increased.
(27) Together, this indicates that in vivo administered ASCs, suppress the
formation of a dermal scar, through augmented wound healing.

Moreover, we believe that the addition of SVF to Platelet-rich Plasma (PRP)
will ameliorate current results of PRP injection into dermal wounds. Thus far,
positive effects of PRP in combination with fat grafts or ASCs on wound healing
and tissue recovery have been shown in human trials (29-31), as well as the use
of PRP as a treatment of chronic and soft tissue ulcerations. In all mentioned
applications, PRP showed to have a positive influence on tissue recovery and
regeneration. In vitro, Willemsen et al. showed that ASCs responded in a
dose-dependent way to PRP addition. Addition of PRP resulted in a decrease of
several paracrine genes, which is relevant to tissue repair and thus wound
healing. (38)

To date, none of the published clinical trials regarding PRP and or
SVF/lipografting for wound healing purposes have been performed in a proper
randomized clinical setting. Therefore, we set up a randomized double blind
clinical trial to prevent scar formation using a substance of adipose tissue:
the stromal vascular fraction, after a mamma reduction (NL55651.000.16). In
this trial, we and participating patients have witnessed improved wound healing
rates in the wound of the breast which has been treated with the stromal
vascular fraction as compared to the placebo group. Unfortunately, in this
study, we only focus on the evaluation of scar formation after 6 months and 12
months postoperative. To objectify these results, we set up a new randomized
double blind clinical trial to improve wound healing rates after a mamma
reduction. In this trial, we focus on the early wound healing phase up to 52
weeks postoperative.

To quantify clinical and histological changes of the skin in promoting early
wound healing when SVF + PRP injectable is used as treatment in comparison to
SVF and PRP alone.

Double blind randomized controlled multi-clinical trial

All patients will randomly receive all treatments in one part of four
predesigned equal parts of the two caudal scars of the mamma reduction wise
pattern. Two equal parts per breast: 1) SVF + PRP (0.1 ml per 0.1 cm2 wound
surface), 2) SVF (0.1 ml per 0.1 cm2 wound surface), 3) PRP (0.1 ml per 0.1 cm2
wound surface) and 4) 0.9% NaCl (0.1 ml per 0.1 cm2 wound surface). Each of the
four different treatments will be applied in a surface area of 1cm by 5cm: part
A is the lateral 5 cm2 starting from the most lateral part of the wound on the
left side, part B is the medial 5 cm2 starting from the most medial part of the
wound on the left side, part C is the medial 5 cm2 starting from the most
medial part of the wound on the right side and part D is the lateral 5 cm2
starting from the most lateral part of the wound on the right side.

During the operation, two 0.2 cm biopsies (into the dermal fat layer) will be
taken out of the resected (normal) skin. After every mamma reduction there will
be some resected skin leftovers. Subjects will already be under full
anaesthesia at the time of the first biopsies and preparation and injection of
the SVF and PRP injectable and/or 0,9% NaCl injectable.
After a period of 2 weeks, 6 weeks, 12 weeks and 52 weeks postoperative each
participant and observer will complete the POSAS Questionnaire for each part of
the scar of each breast (i.e. four questionnaires per consult per patient) and
scars will be photographs in a standardized fashion. Four biopsies (into the
dermal fat layer) will be taken after 6 weeks and 12 weeks, 1 from each part of
the scar of each breast. Each postoperative biopsy will be taken within the
borderline between normal skin and scar, with a maximum size of 0.2 cm.
Subjects will be under local anaesthesia at the time of the second and third
biopsies. The duration of the follow-up moments is estimated at respectively
10, 30, 30 and 10 minutes. The duration of the operation is estimated at 2
hours (1.5 hours for the mamma reduction and half an hour for liposuction,
concentrating the SVF and PRP, and injecting it into the wound edges). Blood
will be drawn before the operation and concentrated during the surgical
procedures. Potential risk of the included subject is low: PRP has been in use
as an adjuvant since 1985. No health risks or (serious) adverse events have
been reported(39) to this date. PRP is currently used for several applications
in domestic and foreign hospitals.
Using SVF as treatment has not ever increased health risks nor has showed to
increase adverse events of any kind to this date.