cornea tissue engineering
y ganji
We are going to introduce new concepts in tissue engineering, every
week we can discuss about one subject and share new related articles.
for the first subject I choose cornea tissue engineering. you can find
some abstracts here, then in the first meeting we discuss about it, so
we can decide what subject is the best for us. if you need more
information about each of them please contact me or Mr. Raz.
Good Luck
In vivo evaluation of a novel scaffold for artificial corneas prepared
by using ultrahigh hydrostatic pressure to decellularize porcine
corneas
Shuji Sasaki,1,2,4 Seiichi Funamoto,3,4,5 Yoshihide Hashimoto,3,4,6
Tsuyoshi Kimura,3,4 Takako Honda,4,7 Shinya Hattori,4,7 Hisatoshi
Kobayashi,4 Akio Kishida,3,4,5 Manabu Mochizuki1
Abstract
Purpose: To evaluate the stability and biocompatibility of artificial
corneal stroma that was prepared by using ultrahigh hydrostatic
pressurization treatment to decellularize corneas.
Methods: The porcine cornea was decellularized by two methods, a
detergent method and an ultrahigh hydrostatic pressure (UHP) method.
Either 1% w/v Triton® X-100 or sodium dodecyl sulfate (SDS) was used
for the detergent method, and 10,000 atmospheres (atm; 7.6×106 mmHg)
was applied to the cornea for 10 min at 10 °C by a high-pressure
machine for the UHP method. Hematoxylin-eosin staining was performed
to confirm the removal of the corneal cells, and then decellularized
porcine corneal stroma was implanted into rabbit corneal pockets.
After eight weeks, the rabbit eyes were enucleated to examine the
tissue compatibility of the implanted stroma.
Results: Complete decellularization was confirmed only in corneas
treated by the UHP method, and little inflammation was seen when they
were implanted into the rabbit corneal pockets.
Conclusions: Porcine corneal stroma completely decellularized by the
UHP method has extremely high biocompatibility and is a possible
corneal scaffold for an artificial cornea.
A collagen-based scaffold for a tissue engineered human cornea:
Physical and physiological properties
Auteur(s) / Author(s)
DOILLON C. J. ; WATSKY M. A. ; HAKIM M. ; WANG J. ; MUNGER R. ;
LAYCOCK N. ; OSBORNE R. ; GRIFFITH M. ;
Résumé / Abstract
Stabilized collagen-glycosaminoglycan scaffolds for tissue engineered
human corneas were characterized. Hydrated matrices were constructed
by blending type I collagen with chondroitin sulphates (CS), with
glutaraldehyde crosslinking. A corneal keratocyte cell line was added
to the scaffolds with or without corneal epithelial and endothelial
cells. Constructs were grown with or without ascorbic acid. Wound-
healing was evaluated in chemical-treated constructs. Native,
noncrosslinked gels were soft with limited longevity. Crosslinking
strengthened the matrix yet permitted cell growth. CS addition
increased transparency. Keratocytes grown within the matrix had higher
frequencies of K+ channel expression than keratocytes grown on
plastic. Ascorbic acid increased uncrosslinked matrix degradation in
the presence of keratocytes, while it enhanced keratocyte growth and
endogenous collagen synthesis in crosslinked matrices. Wounded
constructs showed recovery from exposure to chemical irritants. In
conclusion, this study demonstrates that our engineered, stabilized
matrix is well-suited to function as an in vitro corneal stroma.
Revue / Journal Title
International journal of artificial organs ISSN 0391-3988
Source / Source
2003, vol. 26, no8, pp. 764-773 [10 page(s) (article)]
Corneal Reconstruction with Tissue-Engineered Cell Sheets Composed of
Autologous Oral Mucosal Epithelium
Kohji Nishida, M.D., Ph.D., Masayuki Yamato, Ph.D., Yasutaka
Hayashida, M.D., Katsuhiko Watanabe, M.Sc., Kazuaki Yamamoto, M.Sc.,
Eijiro Adachi, M.D., Ph.D., Shigeru Nagai, M.Sc., Akihiko Kikuchi,
Ph.D., Naoyuki Maeda, M.D., Ph.D., Hitoshi Watanabe, M.D., Ph.D.,
Teruo Okano, Ph.D., and Yasuo Tano, M.D., Ph.D.
ABSTRACT
Background Ocular trauma or disease may lead to severe corneal
opacification and, consequently, severe loss of vision as a result of
complete loss of corneal epithelial stem cells. Transplantation of
autologous corneal stem-cell sources is an alternative to allograft
transplantation and does not require immunosuppression, but it is not
possible in many cases in which bilateral disease produces total
corneal stem-cell deficiency in both eyes. We studied the use of
autologous oral mucosal epithelial cells as a source of cells for the
reconstruction of the corneal surface.
Methods We harvested 3-by-3-mm specimens of oral mucosal tissue from
four patients with bilateral total corneal stem-cell deficiencies.
Tissue-engineered epithelial-cell sheets were fabricated ex vivo by
culturing harvested cells for two weeks on temperature-responsive cell-
culture surfaces with 3T3 feeder cells that had been treated with
mitomycin C. After conjunctival fibrovascular tissue had been
surgically removed from the ocular surface, sheets of cultured
autologous cells that had been harvested with a simple reduced-
temperature treatment were transplanted directly to the denuded
corneal surfaces (one eye of each patient) without sutures.
Results Complete reepithelialization of the corneal surfaces occurred
within one week in all four treated eyes. Corneal transparency was
restored and postoperative visual acuity improved remarkably in all
four eyes. During a mean follow-up period of 14 months, all corneal
surfaces remained transparent. There were no complications.
Conclusions Sutureless transplantation of carrier-free cell sheets
composed of autologous oral mucosal epithelial cells may be used to
reconstruct corneal surfaces and can restore vision in patients with
bilateral severe disorders of the ocular surface.
Biofunctionalization of collagen for improved biological response:
Scaffolds for corneal tissue engineering
Xiaodong Duana, Christopher McLaughlinb, May Griffithb and Heather
Sheardowna
Abstract
Residual dendrimer amine groups were modified with incorporate COOH
group containing biomolecules such as cell adhesion peptides into
collagen scaffolds. YIGSR, as a model cell adhesion peptide, was
incorporated into both the bulk structure of the gels and onto the gel
surface. The effects of the peptide modified collagen gels on corneal
epithelial cell behavior were examined with an aim of improving the
potential of these materials as tissue-engineering scaffolds. YIGSR
was first chemically attached to dendrimers and the YIGSR attached
dendrimers were then used as collagen crosslinkers, incorporating the
peptide into the bulk structure of the collagen gels. YIGSR was also
attached to the surface of dendrimer crosslinked collagen gels through
reaction with excess amine groups. The YIGSR modified dendrimers were
characterized by H-NMR and MALDI mass spectra. The amount of YIGSR
incorporated into collagen gels was determined by 125I radiolabelling
at maximum to be 3.1–3.4×10−2 mg/mg collagen when reacted with the
bulk and 88.9–95.6 μg/cm2 when attached to the surface. The amount of
YIGSR could be tuned by varying the amount of peptide reacted with the
dendrimer or the amount of modified dendrimer used in the crosslinking
reaction. It was found that YIGSR incorporation into the bulk and
YIGSR modification of surface promoted the adhesion and proliferation
of human corneal epithelial cells as well as neurite extension from
dorsal root ganglia.
Keywords: Cornea; Collagen; Dendrimers; YIGSR; Nerve outgrowth;
Epithelialization