Chronic wound healing by fetal cell therapy may be explained by differential gene profiling observed in fetal versus old skin cells
Introduction
Considerable interest and research has been dedicated to the understanding of wound healing and the associated process. Whereas adult cutaneous wounds heal more slowly and with scar formation to restore tissue integrity, fetal skin, in utero, is observed to have rapid and scar-less tissue repair characterized by regeneration of an organized dermis with normal appendages and by a relative lack of inflammation. (Beanes et al., 2002, Bullard et al., 2003, Cass et al., 1997, Adzick and Lorenz, 1994, Armstrong and Ferguson, 1995, Dang et al., 2003, Lorenz et al., 1995). Fundamental differences between fetal and adult skin and the fetal and adult skin wound environment may be important in inducing efficient tissue repair. Chronic wounds, more specifically leg ulcers, are a major health concern. Patient’s suffering has long been underestimated and recent evaluations of quality-of-life reveal that patients with leg ulcers have complaints that are substantial and similar to those previously reported for patients with chronic obstructive pulmonary disease, osteoarthritis or angina (Kahn et al., 2004). Costs are considerable and were calculated to exceed 0.5 billion euros/year in Germany and the direct cost of leg ulcers in the UK were calculated at 400 million euros a year (Hafner et al., 1999). Similarly in the United States, estimations are as high as 3 billion dollars for treatment of all forms of leg ulcers. Important variables for cost differences between countries are the frequency of bandage changes and duration of time for each bandage change (Ragnarson and Hjelmgren, 2005). Etiological treatment of venous ulcers is mandatory in order to prevent relapse. Compression therapy is the cornerstone of venous ulcer treatment and high rates of healing (up to 83% in 6 months) may be obtained by different techniques (Booza et al., 2005). However, such results are not obtained by all teams, and considerable biases of recruitment do exist. In countries with a high standard of health care and a good prevention of venous insufficiency, resistant ulcers are more and more frequent and present as a difficult therapeutic challenge (Chaby et al., 2006, Marklund et al., 2000).
Local methods for accelerating healing are based on modern wound dressings. However, there is no evidence in the literature that their use really improves the healing rate of venous ulcers (Booza et al., 2005). Therefore, there is an urgent need for new techniques in the treatment of refractory leg ulcers.
New biological therapies for wound healing have significantly advanced including growth factors, skin substitutes, gene and stem cell therapies as well as tissue engineering. The origin of cell choice, their interaction with a biomaterial and the simplicity of preparation is extremely important for eventual therapeutic usage.
Autologous skin fibroblasts and substitutes of various nature have been used on leg ulcers to date (Limat et al., 1996, Uccioli, 2003, Caravaggi et al., 2003, Cavallini, 2007) with different degrees of efficiency. Major drawbacks are that production time is long since patient tissues are necessary for processing. Allogenic skin substitutes using foreskin tissue (Dermagraft®, Apligraf® and Orcel®) have shown decreased healing times for diabetic foot ulcers, other ulcers and non-weight bearing wounds (Falanga et al., 1998, Marston et al., 2003). The production time is long and we have recently shown high differences in gene expression of banked fetal and foreskin cells used in tissue engineering (Hirt-Burri et al., 2008) which could be, in part, responsible for differences of efficiency seen in the clinic to date.
As banked fetal skin fibroblasts have been previously shown to efficiently induce tissue repair in burns and in acute wounds (Hohlfeld et al., 2005, de buys Roessingh et al., 2006, Quintin et al., 2007), it was of interest to look at the effect on recalcitrant leg ulcers with different etiologies in the elderly to see if a full clinical trial would be of merit. In this Phase I safety clinical study, we particularly wanted to evaluate the tolerance of multiple treatments with fetal cell biological bandages and interaction with the chronic wound environment. With these specifically banked fetal skin cells used in tissue engineering, we performed microarray analysis to identify differences on the molecular level between specific gene clusters compared to old skin cells, banked in the same manner, which could give some insight into significant parameters involved in efficient wound healing.
Section snippets
Skin donations and cell bank synthesis
Cell lines established in the University Hospital of Lausanne from a fetal skin biopsy at 14 weeks of gestation (14 week male fetal skin;14 wFS) obtained after pregnancy termination with informed and written consent and approval from the local Medical School Ethics Committee. Normal skin from an old male donor (75 yr old skin; 75 yOS) was obtained in the Department of Dermatology in the University Hospital of Lausanne from a non-sun-exposed skin site (buttocks) also with informed consent and
Preliminary assessment of fetal skin constructs on chronic wounds
In a total of 9 patients treated with fetal cell therapy from 3 to 31 weeks concerning 13 ulcers, we were able to see 8 ulcers closed completely, 4 with significant amelioration in size but not complete closure and 1 which was lost to follow-up because the patients estimated that there was a substantial improvement. We present the detail of 4 patients herein as we have completed data including venous (Duplex) and arterial investigations (ABI and duplex) described according to CEAP
Discussion
In the clinical setting, we have seen practical advantages of fetal cell therapy applied to preliminary patients with chronic wounds (Ramelet et al., 2001). The cells are able to exert promoting effects on adhesion, proliferation and migration of existing cells as the repaired wounds tend to heal gradually and the skin is much less atrophic. Also, the pain alleviation following fetal construct application was universal. In other studies using other autologous and allogenous grafting techniques (
Acknowledgments
The authors wish to thank Baxter (Switzerland) for the donation of the matrix (TissueFleece®) for these studies. We also thank Drs. Zwahlen and Poussin for helpful discussions on micro-array analysis. These studies were supported by the Foundation for Orthopedics for Swiss Romande and a grant from Nestlé (Switzerland) for working on aging.
References (57)
- et al.
Ontogeny of the skin and the transition from scar free to scarring phenotype during wound healing in the pouch young of the marsupial Monodelphis domestica
Dev. Biol.
(1995) - et al.
Down-regulation of decorin, a transforming growth factor-beta modulator, is associated with scarless fetal wound healing
J. Pediatr. Surg.
(2001) - et al.
Pleiotrophin induces formation of functional neovaculature in vivo
Biochem. Biophys. Res. Commun.
(2005) - et al.
Fetal wound healing current perspectives
Clin. Plast. Surg.
(2003) - et al.
Developmental roles of the glypicans
Cell Develop. Biol.
(2001) - et al.
Revision of the CEAP classification for chronic venous disorders: consensus statement
J. Vasc. Surg.
(2004) - et al.
Tissue engineered fetal skin constructs for paediatric burns
Lancet
(2005) - et al.
Relationship between clinical classification of chronic venous disease and patient-reported quality of life: Results from an international cohort study
J. Vasc. Surg.
(2004) - et al.
Transforming growth factor beta (TGF-beta) induces fibrosis in a fetal wound model
J. Pediatr. Surg.
(1988) - et al.
Expression profiling of aging in the human skin
Exp. Gerontol.
(2006)
Successful treatment of chronic leg ulcers with epidermal equivalents generated from cultured autologous outer root sheath cells
J. Invest. Dermatol.
Analysis of relative gene expression data using real-time quantitative PCR and the 2−ΔΔCT method
Methods
Hyaluronic acid modulates proliferation, collagen and protein synthesis of cultured fetal fibroblasts
Matrix
Differential expression of fibromodulin, a transforming growth factor-β modulatore, in fetal skin development and scarless repair
Am. J. Path.
Fibulins 3 and 5 antagonize antiogenesis in vivo
Cancer Res.
Cells, matrix, growth factors and the surgeon: the biology of scarless fetal wound repair
Ann. Surg.
Estrogen modulates cutaneous wound healing by downregulating macrophage migration inhibitory factor
J. Clin. Invest.
Confocal microscopic analysis of scarless repair in the fetal rat: defining the transition
Plast. Reconstr. Surg.
Human wound contraction: collagen organization, fibroblasts, and myofibroblasts
Plast. Reconstr. Surg.
Efficacy of modern dressings in the treatment of leg ulcers: a systematic review
Wound Rep. Reg.
Fetal wound healing: current biology
World J. Surg.
HYAFF 1-based autologous dermal and epidermal grafts in the treatment of noninfected diabetic plantar and dorsal foot ulcers
Diabetes Care
Scar wars: implications of fetal wound healing for the pediatric burn patient
Pediatr. Surg.
Autologous fibroblasts to treat deep and complicated leg ulcers in diabetic patients
Wound Rep. Reg.
Refractory venous or arteriovenous leg ulcers: a multifactorial origin
Dermatol. Surg.
Profiling of genes differentially expressed in a rat of early and later gestational ages with high-density oligonuclotide DNA array
Wound Rep. Regen.
Increased vascular endothelial growth factor in hypoxic fetal wounds
Surg. Forum
Development and Characterization of a fetal skin bank for tissue engineering and its clinical application for acute and chronic wounds
Cell Transplant.
Cited by (62)
Glycogen-based hydrogels
2023, Polysaccharide Hydrogels for Drug Delivery and Regenerative MedicineFetal wound healing
2020, Wound Healing, Tissue Repair, and Regeneration in DiabetesA randomized, double-blind, phase I clinical trial of fetal cell-based skin substitutes on healing of donor sites in burn patients
2019, BurnsCitation Excerpt :Considering the fact that fetal skin wounds heal rapidly and regenerate faster compared to adults, it is presumed that fetal cells hold the key for tissue regeneration [12,13]. Several studies have shown that compared to adult fibroblasts, fetal fibroblasts possess greater proliferative and migratory capacity, larger amounts of extracellular matrix deposition and different growth factors [14–16]. Given the importance of fetal fibroblasts in accelerating fetal wound healing, researchers have tried to mimic the fetal wound healing conditions by using fetal cell-based skin substitutes [12,15].
Foetal cell therapy in treatment of burns and wounds
2019, Comprehensive BiotechnologyEstablishing a Xenograft Model with CD-1 Nude Mice to Study Human Skin Wound Repair
2024, Plastic and Reconstructive Surgery
- 1
Present address: Department of Pediatric Surgery, University Hospital, Lausanne.
- 2
These authors contributed equally in this study.