Autologous Graft Material Research Articles

Use of biosynthetic prosthesis (Omniflow II®) to replace infected infrainguinal prosthetic grafts - first results

The current treatment standard of infected infrainguinal prosthetic vascular grafts includes total graft explantation and autologous vascular reconstruction. In the absence of appropriate autologous venous graft material prosthetic grafts with increased bacterial resistance can be used, whereas reinfection rates are still higher than after autologous reconstruction. Biosynthetic grafts have shown low postoperative infection rates when used as elective bypass material. Their higher resistance to bacterial infection could make them an alternative to replace infected prosthetic grafts in the absence of autologous material. Between November 2009 and April 2011, 7 patients with infected infrainguinal prosthetic grafts (Szilagyi 3; 3 supragenicular and 4 infragenicular reconstructions) presented to our institution. There were 4 early (< 3 months after implantation) and 3 late infections (> 3 months after implantation. All grafts were explanted and replaced by biosynthetic grafts (Omniflow II®), because the patient had no suitable peripheral vein for complete autologous replacement. In 2 cases a composite graft with greater saphenous vein was done. In 6 cases microbiological cultures from intraoperatively obtained species were positive. The initial broad spectrum antibiotic therapy was continued according to the antibiogram for 6 to 12 weeks. There was no early or late reinfection during follow up (mean 9 months, range 4 - 20 months). During follow up we observed graft occlusions in 3 patients (1 due to kinking of the bypass, 1 due to progressive artheriosclerotic occlusion of the outflow vessels and 1 iatrogenic by external compression with a pressure cuff during arthroscopy). There were no early or late major amputations. One patient died with pneumonia 11 months postoperatively. In the absence of appropriate autologous material biosynthetic grafts seem to be a possible alternative to replace infected infrainguinal grafts. The different mechanical properties of biosynthetic grafts may be of certain disadvantage in infragenicular reconstructions.

Mixture of hyaluronic acid, chondroitin 6 sulphate and dermatan sulphate used to completely regenerate bone in rat critical size defect model

Skeletal bone losses are mainly filled with autologous graft or artificial materials. Osteoblasts are essential to maintain bone homeostasis and bone repair through a matrix synthesis. We have previously demonstrated that adherence and regenerative matrix composition are fundamental to bone healing, even in critical situations. In this work the critical size defect technique was used to evaluate the systemic activity on bone regeneration of a novel mixture of extracellular polysaccharides. A 5mm diameter hole was made in each parietal bone of male Wistar rats. The right parietal bone hole was filled with a mixture of hyaluronic acid, chondroitin 6 sulphate, and dermatan sulphate mixed with 2.5% NaCl solution, while the left hole was left free of material and untreated and considered as control. Twenty-one days after surgery, the holes and surrounding tissues were examined visually, using X-rays, and by histological staining. Using the matrix substitute, bone healing was almost complete after 21days in the treated hole and always complete in the control side due to some systemic effect. Neovascularization was also observed along with organized trabecular bone on both sides. No abnormal bone growth or connective tissue abnormalities were noted. At the end of the experiment, 95.1% (±3.2) bone healing (n=20) was observed on the treated side; conversely, healing bone and histological structure were better on the control side.

Ostéotomies de repositionnement de l’os zygomatique

The main morphological sequels of zygomatic bone fractures are lack of zygomatic projection and enopthalmia. They may be corrected by zygomatic osteotomy which is a difficult operation because of modified anatomic landmarks. Onlay bone or alloplastic grafts are preferred. Zygomatic osteotomies are performed through three surgical approaches: superior palpebral, sub-ciliary, and upper vestibular, followed by repositioning with osteosynthesis micro-plates. They allow reconstruction with an adequate projection in three dimensions. Surgery is usually associated with a bone graft of the orbital floor. Zygomatic osteotomy is a simple, reproducible technique, but it requires a good bone exposure. The esthetic results are satisfactory with an uneventful outcome. This surgical procedure is a good alternative to isolated techniques of autologous bone grafting or alloplastic material reconstruction which have sometimes disappointing and short lasting results due to graft resorption.

Osteoconductivity and osteoinductivity of NanoFUSE® DBM

Bone graft substitutes have become an essential component in a number of orthopedic applications. Autologous bone has long been the gold standard for bone void fillers. However, the limited supply and morbidity associated with using autologous graft material has led to the development of many different bone graft substitutes. Allogeneic demineralized bone matrix (DBM) has been used extensively to supplement autograft bone because of its inherent osteoconductive and osteoinductive properties. Synthetic and natural bone graft substitutes that do not contain growth factors are considered to be osteoconductive only. Bioactive glass has been shown to facilitate graft containment at the operative site as well as activate cellular osteogenesis. In the present study, we present the results of a comprehensive in vitro and in vivo characterization of a combination of allogeneic human bone and bioactive glass bone void filler, NanoFUSE(®) DBM. NanoFUSE(®) DBM is shown to be biocompatible in a number of different assays and has been cleared by the FDA for use in bone filling indications. Data are presented showing the ability of the material to support cell attachment and proliferation on the material thereby demonstrating the osteoconductive nature of the material. NanoFUSE(®) DBM was also shown to be osteoinductive in the mouse thigh muscle model. These data demonstrate that the DBM and bioactive glass combination, NanoFUSE(®) DBM, could be an effective bone graft substitute.

Endoscopic skull base surgery and its impact on sinonasal‐related quality of life

Endoscopic skull base surgery (ESBS) is considered a minimally-invasive surgical modality with less morbidity and patient discomfort. Quality-of-life (QOL) assessments provide a patient-reported estimate of well-being that may be clinically relevant. Although the sinonasal tract is integral to ESBS, the change in sinonasal-related QOL with ESBS has not been well studied. The aim of this study was to prospectively assess QOL before and after ESBS using validated outcome measures. Consecutive adult patients undergoing ESBS for anterior skull base lesions were prospectively enrolled from a tertiary referral center. Each patient was asked to complete the 22-item Sinonasal Outcome Test (SNOT-22) and the Anterior Skull Base Questionnaire (ASBQ) preoperatively, and again at 3 weeks, 6 weeks, 12 weeks, 6 months, and 1 year postoperatively. Eighty-five patients were included for study, 44.7% of whom underwent ESBS for nonpituitary pathology. Mean SNOT-22 scores transiently worsened in the early postoperative period, and significantly improved at 1 year after surgery (p < 0.01). Gross-total tumor resection and use of autologous grafting materials were associated with improved SNOT-22 scores at later time points (p < 0.05). Type of reconstruction, tumor pathology, and functionality did not affect QOL scores. Correlation between SNOT-22 and ASBQ scores was good at all time points (r < -0.50). Cerebrospinal fluid leak and other complications were uncommon. ESBS does not have a detrimental long-term effect and is associated with ultimate improvement in sinonasal-related QOL. Short-term impairments of sinonasal-related QOL are predictable and self-limited. Prospective assessment using sinonasal-related and site-specific QOL instruments provide complementary information about ESBS outcomes.

Bone and cartilage harvesting techniques in rhinoplasty

Maintaining structural integrity during rhinoplasty often necessitates adding support to the nose. Autologous grafting material is the safest and most reliable source of this structural support. A variety of sources in the body can serve as donor sites for such grafts. The most common sites are septal cartilage, auricular conchal cartilage and rib cartilage. Less common sites include tragal cartilage, calvarial bone and iliac bone. This article reviews the surgical techniques for accessing, harvesting, and modifying these grafts for use in rhinoplasty.

Improved adhesion of human cultured periosteal sheets to a porous poly(L‐lactic acid) membrane scaffold without the aid of exogenous adhesion biomolecules

Human cultured periosteal sheets, which are developed from small excised periosteum tissue segments (PTSs) in culture dishes by simple expansion culture, have been applied as a promising autologous osteogenic grafting material for periodontal regenerative therapy. However, the weak initial adhesion of PTSs to dish surfaces often hampers cellular outgrowth and limits the number of preparations. To correct this weakness and still avoid the use of animal-derived adhesion biomolecules, we have developed a novel, biodegradable, porous poly(L-lactic acid) (pPLLA) membrane. Freshly excised PTSs bound well to the highly porous pPLLA membrane, possibly due to the presence of semihemispheric 20-30 μm diameter openings on the upper surface. Global gene expression analysis demonstrated that periosteal sheets cultured on pPLLA membranes upregulated expression of many adhesion molecules. Osteogenic induction stimulated the production of proteoglycans by these cells and concomitantly enhanced their expansion and penetration into the deep pore regions of the membrane in parallel with the progression of in vitro mineralization. These findings suggest that our pPLLA membranes not only facilitate initial adhesion, primarily mediated by adsorbed proteins, but also enhance biological adhesion by inducing endogenous adhesion molecules in periosteal sheet cultures. Therefore, the efficacy of periosteal sheets in therapy should be greatly enhanced by using this new pPLLA membrane.

Methods of Cell-Based Bone Regeneration-Mini Review

The requirement for bone tissue grafting exists in a wide range of clinical conditions involving surgical reconstruction, following trauma or other pathological conditions, particularly in the limbs, spine and skull. The amount of bone tissue required for grafting and the destination of the graft material affect the origin of the grafting material. There are serious disadvantages in the use of various grafting sources, such as autografts, allografts and inorganic bone substitutes. The possibility of enhanced generation of a sufficient amount of autologous metabolically active bone, with high bone inductive and bone conductive properties, for implantation should resolve the difficulties and complications of the currently used bone grafting techniques. For this purpose, several methods based on bone generating cells implantation on osteoinductive matrices in vivo and in vitro were proposed and submitted for patent registration. Several patents describe the possibility for autologous bone grafting material generation, either in vitro, from bone generating cells cultured on inorganic matrix prior to implantation, or by direct implantation of mesenchymal cells into the bone gap in vivo. Currently there is not enough evidence as to which approach is advantageous for a clinical use. The reason for this uncertainty is the lack of clinical experimental data for both methods. Keywords: Bone, bone graft, bone regeneration, in vitro, in vivo, mesenchymal stem cells, tissue engineering, osteoblast

Association cellules–matériaux pour thérapies cellulaires osseuses

Although autologous or allogenous bone grafting materials are widely used to repair skeletal tissue, their limitations induce surgeons to look for more advanced therapies such as tissue engineering. However, bone tissue engineering still lacks proofs of clinical efficacy, possibly due to the inadequate design of the tissue-engineered constructs in relation to the natural tissue. Our aim is therefore to design an engineered construct that mimics the three main components of bone (osteoblastic cells, collagen extracellular matrix and apatite crystals). Human bone marrow contains mesenchymal stem cells that differentiate into osteoblasts. These osteoprogenitors have been cultured on calcium phosphate ceramics producing collagen extracellular matrix in vitro and inducing ectopic bone tissue formation in vivo. Cellulosic hydrogels associated to calcium phosphate particles have been used for preparing injectable bone substitutes. These injectable materials are particularly attractive for delivering osteoprogenitor cells in to bone defects using minimal invasive surgery. Bone tissue engineering using autologous MSC and biomaterials may become in future an attractive approach for the reconstruction of large bone defects in orthopaedic, spine and maxillo-facial surgeries.

Current status of the surgical management of Peyronie's disease

Surgery is the standard treatment for patients in the chronic phase of Peyronie's disease. Reconstructive surgeries function by either shortening the convex side of the tunica albuginea (Nesbit procedure, Yachia technique and penile plication) or lengthening the concave side by incision of the plaque with subsequent grafting. Tunical shortening procedures are ideal for men with good erectile capacity, penile curvatures less than 60° and predicted postprocedural length loss of less than 20% of erect penis length. Tunical lengthening procedures with grafting are indicated in patients with severe penile length loss, curvatures greater than 60° and prominent hourglass deformities. Saphenous vein and tunica albuginea are the most commonly used autologous graft materials. Cadaveric or bovine pericardium and 4-layer small intestinal submucosa are promising nonautologous tissues. Penile implantation of a prosthesis is the standard procedure in men with erectile dysfunction who do not respond to conservative treatment. If residual penile curvature is less than 30° after implantation, no further treatment is required. However, residual curve of greater than 30° can be straightened with manual modeling. Additional procedures such as penile plication, the Nesbit procedure, or grafting can be performed if modeling fails to correct the residual deformity.

Tibial plateau fractures: Internal fixation with locking plates and the MIPO technique

Proximal tibial fractures are difficult lesions to treat because of the involvement of the articular surface, the often occurring comminution, and the precarious condition of the soft tissues, especially following high-energy trauma. Aim of the treatment is to restore the congruence of the articular surface supporting the tibial plateau cartilage which is usually depressed; to fix the fracture with a stable device; to allow early rehabilitation. We present our treatment strategy, utilising closed or open reduction and internal fixation, angle-stable polyaxial plates, immediate osteointegration, when necessary, with autologous bone graft or other osteoconductive material augmented with autologous platelet gel. Surgery is soft-tissue dependent in terms of timing, and it is usually performed directly or under supervision of an experienced surgeon utilising, whenever possible, a tissue sparing technique. A cohort of 58 proximal tibial fractures, surgically treated, from January 2004 to June 2007, was retrospectively reviewed. Fractures were classified according the OTA/AO classification. The assessment of the functional outcome with the use of the Rasmussen score identified good to excellent results in 78% of the cohort 12 months post-surgery. Internal fixation with locking plates, following the principles of MIPO (Minimally Invasive Percutaneous Osteosynthesis), provides satisfactory fracture reduction with good results regarding the mid-term clinical outcome.

Recycling the Dorsal Hump: A Simple Technique to Prevent Dorsal Irregularities in Primary Rhinoplasty

Sir: Dorsal nasal irregularities are common aesthetic deformities following primary and secondary rhinoplasty, especially in patients with thin nasal dorsal skin. The authors present a simple technique of obtaining autologous graft material, by collecting the remnants of rasped osseocartilaginous dorsum, which is used as a routine in their rhinoplasty practice. The authors prefer open rhinoplasty in all patients. After transcolumellar and infracartilaginous incisions, a distally subperichondrial and proximally subperiosteal pocket is developed over the osseocartilaginous dorsum. A nasal dorsum rasp is introduced into this space and the dorsal hump is removed by rasping alone. During rasping, tiny fragments of bone and cartilage are produced from the breakdown of osseocartilaginous dorsum (Fig. 1). These particles are collected meticulously from the surface of the rasp by drying the rasp on a piece of gauze or from the pocket with an atraumatic forceps. Aspiration of blood by the assistant is not allowed at this stage. Hemostasis is achieved by sponges, and these sponges are also preserved for collecting any particles attached on them. When all particles are gathered and dried over a piece of gauze, a solid “meatball” of osseocartilaginous graft material is obtained (Fig. 2). This graft material is placed on the osseocartilaginous dorsum just before closure of incisions, and the nose is taped and splinted.Fig. 1.: Tiny fragments of bone and cartilage are formed by rasping the nasal dorsum.Fig. 2.: These particles are gathered into a “meatball” composite graft.This technique, which was used as a routine in 562 primary open rhinoplasties between 2002 and 2008, simply eliminated postoperative dorsal nasal irregularities in our rhinoplasty practice. Prevention of dorsal irregularities that may occur even in the most experienced hands is much easier than treating them. The authors believe that in primary rhinoplasty of patients with thin dorsal nasal skin, a maneuver that adjusts the smoothness and softness of nasal dorsum should be a part of the routine. Many techniques have been suggested in attempts to prevent visible sharp edges of dorsal nasal structures, most of which involve placement of soft, smooth, pliable grafts of autologous or alloplastic origin such as fat, diced cartilage, fascia, bone chips, AlloDerm (LifeCell Corp., Branchburg, N.J.), polytetrafluoroethylene patches, silicone sheets, and Vicryl (Ethicon, Inc., Somerville, N.J.) mesh.1–4 Our technique is simply about returning the rasped osseocartilaginous hump to where it belongs. Absence of additional donor-site morbidity is a major advantage over most autologous graft options. Lower cost and avoidance of infectious complications are advantages over alloplastic materials. Prolonged edema, which is common after contouring with dermis grafts or AlloDerm, is not seen with this technique. No envelope or wrapping is necessary. The adequacy of graft material obtained with this technique may be a subject of curiosity. In our opinion, the higher level of control that is provided by rasp removal of dorsum diminishes the amount of material that is necessary to camouflage subtle irregularities in primary rhinoplasty. In cases where additional volume is desired, especially in secondary rhinoplasties, remnants of septal, conchal, or costal cartilages that are left on the table after placement of grafts can be rasped on the table and added to the meatball. DISCLOSURE Neither of the authors has a financial conflict of interest to disclose with regard to the content of this article. Aycan Kayikçioğlu, M.D. Ozan Bitik, M.D. Hacettepe University Faculty of Medicine Department of Plastic, Reconstructive, and Esthetic Surgery Ankara, Turkey

Use of titanium mesh in laryngotracheal reconstruction: an experimental study on rabbits

Titanium mesh may be an alternative material to be used in laryngotracheal reconstruction. Twenty New Zealand rabbits were divided into two groups. Group A underwent laryngotracheoplasty with titanium mesh-buccal mucosa-muscle complex, and Group B received auricular cartilage grafts. All animals survived without complications. The animals were killed at 60 days, and laryngotracheal regions were evaluated. There was no subglottic collapse at physiologic and supraphysiologic negative airway pressures in Group A and mild-moderate collapse in Group B. Macroscopically the average antero-posterior and lateral diameters were not statistically different among two groups. Light microscopic examination revealed no fibrosis, necrosis or new cartilage formation in both groups. Inflammation and granulation were more pronounced in Group A. The lumens in both groups were moderately obstructed. Reconstruction of the upper airway with titanium mesh may be used in very selected cases where autologous grafting materials are inadequate and unsatisfactory.

Abdominal fat harvest technique and its uses in maxillofacial surgery

Abdominal fat harvest and augmentation to the maxillofacial region is a relatively inexpensive, safe, and readily available procedure. The use of abdominal fat free transfer has been well documented for cosmetic, trauma, and temporomandibular joint reconstruction. Fat is the closest we have to an ideal filler, it is readily available and inexpensive, it is autologous and therefore lacks a host immune response, it is safe and noncarcinogenic, and it is easily acquired with a minimally invasive procedure. Abdominal fat donor site is the most commonly used owing to ease of access and availability of fat stores. Complications are rare and easily managed in the office. Free abdominal fat harvest is a predictable surgical technique that allows the maxillofacial surgeon access to autologous graft material that is ideal for multiple facial procedures.

Surgical and minimally invasive treatments for Peyronieʼs disease

Peyronie's disease is a relatively common condition affecting men with estimates of current prevalent rates ranging from 1 to 4%. However, it has no clear management protocols, primarily due to a lack of high quality evidence in support of treatment options. This article aims to review the recent published literature on management strategies for Peyronie's disease. Intralesional interferon therapy has shown to result in significant improvement in Peyronie's disease plaques and curvature. Intralesional verapamil and extracorporeal shock wave therapy may help retard the progression of disease. Acellular, extracellular matrix-based grafts provide durable long-term satisfactory results in men requiring complex reconstruction. Further clinical trails are warranted to evaluate the role of oral systemic therapies for early Peyronie's disease. Injection therapy, primarily with interferon, seems to be the most promising treatment for early stage Peyronie's disease. For men with established plaques, surgery using either plication or grafts forms the mainstay. There is an increasing trend to use autologous graft material that is commercially available and avoids donor site complications from autologous tissue.

Venous Resection in Urological Surgery

Complete removal of retroperitoneal and pelvic tumors may require resection or ligation of major retroperitoneal, pelvic and mesenteric venous structures. We provide an overview of venous anatomy and collateral drainage, and review the veins that can be safely resected. We reviewed major anatomical texts, and performed a directed MEDLINE literature search of retroperitoneal, pelvic and mesenteric venous anatomy. Resection and reconstruction of these vessels were also reviewed with an emphasis on collateral blood flow and post-resection sequelae. The infrarenal inferior vena cava, iliac veins, left renal vein, lumbar veins, inferior mesenteric vein and splenic vein may be resected or ligated without reconstruction. Resection of the right renal vein results in renal demise in the majority of instances. The portal vein may not be resected without reconstruction. Venous reconstruction may be performed with autologous or synthetic graft material. Most major veins in the body can be safely resected or ligated with minimal sequelae. However, it is imperative to understand venous anatomy and collateral blood flow to minimize intraoperative and postoperative complications.

Abdominal Sacrocolpopexy: Anatomic Outcomes and Complications With Pelvicol, Autologous and Synthetic Graft Materials

In abdominal sacrocolpopexy (ASC), a graft is used to secure the apex of the prolapsed vagina to the anterior longitudinal ligament of the sacrum. This retrospective cohort study enrolled women having ASC (abdominal sacrohysteropexy or abdominal sacral colpoperineopexy) in the years 2001–2005. Synthetic mesh was used in 52% of 259 ASC procedures; porcine dermis (Pelvicol) in 39%; and autologous fascia in 9%. Patients in whom synthetic mesh was used were older than others, more likely to have had hysterectomy, and likelier to be postmenopausal. Concomitant surgery was performed least often in the synthetic mesh group. Postoperative follow-up averaged 1.1 years. The primary outcome was anatomical failure of ASC at the apical compartment. Rates of apical failure were 11% when Pelvicol was used, 7% with autologous fascia, and 1% with synthetic mesh. All 7 reoperations necessitated for apical prolapse were in the Pelvicol group. Intraoperative and immediate postoperative complications were comparably frequent in the 3 treatment groups. Intraoperative problems included cystotomy in 6% of patients, enterotomy in 1.5%, and a single ureteral injury. Erosions occurred in 11% of the Pelvicol group. Similar numbers of reoperations for graft-related complications were required in all groups. The most common such complications were granulation tissue formation and erosion. These results show that ASC is likelier to fail when Pelvicol is used rather than synthetic mesh or autologous fascia. In addition, using Pelvicol did not lessen the risk of graft-related complications in this study population.

Abdominal sacrocolpopexy: anatomic outcomes and complications with Pelvicol, autologous and synthetic graft materials

The purpose of this study was to compare anatomic outcomes and graft-related complications (GRCs) for abdominal sacrocolpopexy (ASC) with Pelvicol (CR BARD, Murray Hill, NJ), autologous fascia, and synthetic grafts. This is a retrospective cohort study of ASC from 2001-2005. We reviewed anatomic outcomes and GRCs. Apical failure was defined as >stage 0. Of 259 ASC procedures, Pelvicol was used in 102 procedures (39%); synthetic mesh in 134 procedures (52%), and autologous fascia in 23 procedures (9%). Mean postoperative follow up was 1.1 years. Apical failure by graft group were Pelvicol 10 (11%), synthetics 1 (1%), and autologous 1 (7%; P = .011). All 7 reoperations for apical prolapse were in the Pelvicol group. GRCs occurred in 16% of the cases, with a higher proportion of erosions in the Pelvicol group (11% vs 3% and 4%; P = .045). Reoperations as a result of GRC were similar between groups. ASC is more likely to fail with Pelvicol than with synthetic or autologous grafts. The use of Pelvicol did not reduce graft-related complications in this population.

Catcher's mask cranioplasty for extensive cranial defects in children with an open head trauma: a novel application of partial cranioplasty

In children who have suffered a severe, extensive head trauma, cranioplasty is complicated because allografting is not advisable in pediatric patients and the amount of available autologous materials is limited. To overcome these problems, we employed a combination of autologous rib grafts and calvarial grafts for partial cranioplasty. We named this partial cranioplasty technique 'catcher's mask cranioplasty'. Rib grafts were placed mimicking a baseball catcher's mask to obtain maximum strong coverage of the defect. Calvarial grafts were used to achieve a smooth forehead contour. Islands of osteoanagenesis were also used. These autografts were of sufficient strength, esthetically satisfactory, and no patient developed sinking skin flap syndrome. Catcher's mask cranioplasty is a useful technique to successfully reconstruct the skull in pediatric patients with extensive cranial defects and an insufficient amount of autologous graft material.

The peritoneal cavity as a bioreactor for tissue engineering visceral organs: bladder, uterus and vas deferens

Our objective was to produce avascular, myofibroblast-rich tissue capsules for use as autologous grafts for hollow, smooth muscle-walled visceral organs-bladder, uterus and vas deferens. To produce tissue for grafting, templates of the appropriate shape were implanted in the peritoneal cavities of rats or rabbits. After 2-3 weeks, the templates were removed, the encapsulating myofibroblast-rich tissue harvested and grafted to replace resected segments of bladder, vas deferens or uterus of the same animals in which the tissue was grown. Bladder grafts showed 100% patency after 14 months and had developed a morphology similar to normal bladder. Tubes of myofibroblast tissue grafted unilaterally into resected rabbit vasa deferentia developed a morphology resembling native tissue, with sperm in the ejaculate indicative of normal function. At 12 weeks after grafting, uterine graft tissue had increased in thickness and developed the morphology of normal uterus, with endometrium overlying several layers of smooth muscle cells (myometrium-like) which were interspersed with collagen fibrils; grafted uterine horns supported embryos to the late stages of gestation. This study shows that myofibroblast tissue produced in the peritoneal cavity is sufficiently plastic to permit differentiation of cells into bladder, vas deferens or uterine smooth muscle. As a method for producing autologous graft material for repair/replacement of these organs, this approach has many benefits over conventional and current tissue-engineering strategies.