Biomedical Engineering Reference
In-Depth Information
an aerosol (Wood
et al
., 2006). This non-cultured cell suspension can be generated
using a ReCell autologous cell harvesting device with early evidence of efficacy
(Wood
et al
., 2007). Soaking Integra in a cell suspension harvested using the
ReCell system appears to have the same self-organizing effect (Wood
et al
., 2007)
as cell suspensions centrifuged within a seeded scaffold (Orgill
et al
., 1998).
Seeding dermal scaffolds with autologous keratinocytes is required to acceler-
ate the kinetics of organ regeneration, but is not required to affect the outcome
itself (regeneration versus repair) (Yannas, 2005a). In spite of allowing a one-step
technique, scaffolds seeded with keratinocytes still induce only partial skin
regeneration, mainly owing to the fact that the regenerated tissue still lacks
appendages (Yannas, 2005a, b). Hair follicles can be implanted into Integra by
micrografting techniques to re-epithelialize the area and allow hair growth (Navsaria
et al
., 2004), but add morbidity and do not guarantee an adequate cosmetic result.
Recently it has been shown that bulge cells, from hair follicles, not only
contribute to the epidermis (up to 25% of the cells) during wound healing (Ito
et al
.,
2005; Lavker and Sun, 2003), but after isolation, when combined with neonatal
dermal cells, regenerate new hair follicles, epidermis and sebaceous glands
(Blanpain
et al
., 2004; Morris
et al
., 2004). Since many surface markers of bulge
cells have been recently isolated (Mitsiadis
et al
., 2007; Ohyama
et al
., 2006;
Rochat
et al
., 2007), including CD200 and FRIZZLED receptor on human bulge
cells by laser capture microdissection and microarray analysis for gene expression,
the stage is set to isolate bulge cells to seed collagen matrices and regenerate
appendages in one step with dermis and epidermis (Cotsarelis, 2006a, b).
13.4 References
Blanpain C, Lowry WE, Geoghegan A, Polak L and Fuchs E (2004). 'Self-renewal,
multipotency, and the existence of two cell populations within an epithelial stem cell
niche'.
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Butler CE, Orgill DP, Yannas IV and Compton CC (1998). 'Effect of keratinocyte seeding
of collagen-glycosaminoglycan membranes on the regeneration of skin in a porcine
model'.
Plast Reconstr Surg
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101
, 1572-9.
Butler CE, Yannas IV, Compton CC, Correia CA and Orgill DP (1999). 'Comparison of
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replacements'.
British Journal of Plastic Surgery
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Compton CC, Butler CE, Yannas IV, Warland G and Orgill DP (1998). 'Organized skin
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in vivo
from collagen-GAG matrices seeded with autologous
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Cotsarelis G (2006a). 'Epithelial stem cells: a folliculocentric view'.
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J Clin Invest
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Ito M, Liu Y, Yang Z, Nguyen J, Liang F, Morris RJ and Cotsarelis G (2005). 'Stem cells in
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Nature Medicine
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