Esophageal tissue engineering: A new approach for esophageal replacement

Table 1 Overview of in vivo transplantation of acellular matrices

Animal model (n)			Results		Ref.
	Scaffold type	Size	Scaffold regeneration	Clinical course
Canine (19)	Collagen with silicon stent (not removed)	5 cm circumferential gap, cervical esophagus	Partial epithelial regeneration	26% mortality	[28]
Canine (26)	Collagen with silicon stent (removed between 2 and 8 wk)	5 cm circumferential gap, cervical esophagus	Epithelial regeneration, no stenosis	0% mortality when stent dislodged after 4 wk (n = 4)	[29]
Canine (7)	Collagen with silicon stent (removed at 6 wk)	10 cm circumferential gap, cervical esophagus	Epithelial and partial muscular regeneration, no stenosis	29% mortality	[30]
Canine (43)	Collagen with silicon stent (removed either at 2, 3 or 4 wk)	5 cm circumferential gap, cervical esophagus	Epithelial and muscular regeneration, no stenosis	0% mortality when stent was removed at 4 wk (n = 16)	[31]
Canine (9)	Collagen with silicon stent (removed at 4 wk)	5 cm circumferential gap, thoracic esophagus	Epithelial but no muscular regeneration, mid-portion stenosis	11% mortality	[32]
Canine (14)	Collagen with silicon stent (removed at 4-8 wk) +/- OMPx	5 cm circumferential gap, thoracic esophagus	Epithelial regeneration, mid-portion stenosis	11% mortality in control group, 80% in OMPx group	[33]
Canine (15)	Extracellular matrix scaffold from either small intestine (n = 12) or urinary bladder submucosa (n = 3)	5 cm semi-circumferential or 5 cm circumferential, cervical esophagus	Mucosal and muscular regeneration. Stenosis in case of complete circumferential defects	0% mortality	[44]
Pigs (10)	Elastin based acellular biomaterial patch (from porcine aorta)	2-cm circular defect, abdominal esophagus	Mucosal and muscular regeneration	0% mortality. No complications reported in treatment groups	[43]
Canine (12)	Urinary bladder matrix scaffold	Complete transection with replacement of endomucosa with matrix	Mucosal and muscular regeneration	0% mortality. No complications reported in treatment groups	[48]
Rats (67)	Small intestinal submucosa patch graft	Semi-circumferential defect, cervical or abdominal esophagus	Mucosal and muscular regeneration at 150 d	94% survival at 150 d	[50]
Rats (85)	Small intestinal submucosa patch graft, or tube interposition	Semi-circumferential defect or segmental esophageal excision	Tube interposition unsuccessful. Mucosal and muscular regeneration at 150 d in patch-group	100% survival for patch-group (and no complications reported), 0% survival for tube interposition group at 28 d	[52]
Rats (27)	Gastric acellular matrix scaffold	Patch defects, abdominal esophagus	Mucosal regeneration seen at 2 wk. No muscular regeneration seen up to 18 mo	11% complication rate	[49]
Pigs (14)	Small intestinal submucosa (tubular)	4-cm defect, cervical esophagus	Prosthesis not found either macroscopically or histologically	Only 1 pig survived the full 4 wk study. The other pigs have to be sacrificed prematurely due to severe stenosis	[51]
Human (5)	Porcine small intestinal mucosa	8-cm to 13-cm en-bloc resection of mucosa and submucosa for superficial carcinoma	Restoration of normal mucosa as early as 4 mo	Strictures; perforation in one patients	[45]
Human (1)	Porcine small intestinal mucosa	5 cm × 3 cm defect cervical esophagus	Intact esophagus with normal calibre	No complications encountered	[46]