Tissue engineering trachea is an artificial trachea with biological activity, which is constructed in vitro by using tissue engineered principle and technology, and is a tracheal prosthesis for replacing large circumferential defect of the trachea. The course of its construction is as follows. First, seeding cells are cultured and expanded in vitro. Then they are collected, counted and seeded onto the biomaterial scaffold of tissue consistent and biodegradation. Finally, the biomaterial-cells construction is implanted into bio-reaction device or one’s subcutaneous layer. The tissue engineering trachea could be constructed after cultured certain times. Compared with other artificial trachea, the tissue engineering trachea has more advantages, such as nonimmunogenicity, no side-effects related to foreign graft materials, and biologic activity. This will bring some hope to look for an appropriate graft material. However, the study about it is still faced with some difficult problems, such as vascularized trachea, culturing in vitro, and prevention of infection in trachea prosthesia. So there will be long time for tissue engineering trachea to apply clinical tracheal transplantation successfully. This assay has reviewed the study about tissue engineering trachea from three sides——the source of seeding cells, the research about biomaterial scaffold, and the construction of tissue engineering trachea.
Objective To investigate effect of the removal of epithelium and mixed glands from the tracheal allografts on the graftimmunosuppression. Methods Fresh untreated tracheal allografts， cryopreserved tracheal allografts, and 10 off-epithelium tracheal allografts were obtained from 25 male SD rats. Fresh untreated tracheal allografts(40) were divided into 4 groups and dipped respectively in the solution of protease ⅩⅣ in 0, 0.1, 0.3 and 0.5 mg/ml at 4℃ for 12 hours. Thirty recipient male SD rats were randomly and equally divided into group A (fresh untreated tracheal allografts), group B(cryopreserved tracheal allografts), and group C(offepithelium tracheal allografts). The transplanted allografts were implanted into the abdominal cavity of other rats by being embedded in the greater omentum. Twenty-one days after transplantation, the tracheal graft segments were surgically removed, and then were initially fixed in cold 10% neutral buffered formalin solution for hematoxylineosin staining. Histological observation and lymphocyte infiltration were performed on the grafts to evaluate rejection. Results The 0.3 mg/ml protease ⅩⅣ could remove the epithelium and mixed glands of the grafts completely, but did no damage to cartilage. The cartilages of each group all survived and were revascularized. The lumens of group A were filled with granulation and necrosis tissue. In contrast, group B was filled with a few granulation tissues and group C was not at all. The number of lymphocyte infiltration in group A, B, and C was 29.16±2.69/HP, 15.17±2.19/HP, and 11.56±0.87/HP respectively. There was significant difference between group A and both group B and group C (Plt;0.05), and there was significant difference between group B and group C (Plt;0.05). Therefore, the grade of graftrejectionwas group Agt;group Bgt;group C. Conclusion The 0.3 mg/ml protease ⅩⅣ can completely remove the epithelium and mixed glands of grafts at 4℃ for 12 hours, and it preserves the normal structure of cartilage. The antigenicity of tracheal grafts can be greatly reduced by removing the epithelium and by the cryopreservation. The prior tracheal allograft in the omentum is feasible for the revascularization of the grafts.
OBJECTIVE: To compare the effect of several types of rib rings with intercostal muscles for the replacement of trachea in thorax. METHODS: The surface layer of the third rib of dogs were ripped off and curved into triangular, quadrilateral and polygonal form. These three types of rib rings with intercostal muscles were used to replace a segment of trachea in thorax. RESULTS: The stability of triangular rib ring was very well, but stricture of ring were often happened because of its smaller internal diameter. These stability of quadrilateral rib ring was the worst. The polygonal rib ring presented the biggest diameter and good stability compared to the other two kinds of rings. If silicone tube was supplemented in the polygonal rib ring, the quality of artificial trachea was excellent. CONCLUSION: The rib rings with intercostal muscles are successfully used for replacing the defect of trachea in canine thorax. The polygonal rib rings have the best quality in the three types of rib ring for tracheal replacement.
In vivo transplantation of tracheal grafts utilizes natural environment in vivo to improve cell adhesion, growth and scaffold properties, which can not only promote graft revascularization, but also induce immune tolerance and increase postoperative survival rate. Decellularized trachea with stem cells covering the outside layer and airway epithelial cells covering the inside layer can achieve complete mucosa re-epithelialization, cartilage cell growth and revascularization, using own body as a natural bioreactor to boost the maturity of tissue engineered trachea. Then transplantation at a normotopic in situ positioning is performed. This transplantation strategy provides a promising approach for the treatment of long-segment tracheal defects. This review focuses on the significance and research progress of constructing tissue engineered trachea in vivo.
Objective
To construct a new composite artificial trachea and to investigate the feasibility of trachea repair and reconstruction with the new composite artificial trachea transplantation in dogs.
Methods
The basic skeleton of the new composite artificial trachea was polytetrafluoroethylene vascular prosthesis linked with titanium rings at both ends. Dualmesh was sutured on titanium rings. Sixteen dogs, weighing (14.9 ± 2.0) kg, female or male, were selected. The 5 cm cervical trachea was resected to prepare the cervical trachea defect model. The trachea repair and reconstruction was performed with the new composite artificial trachea. Then fiberoptic bronchoscope examination, CT scan and three-dimensinal reconstruction were conducted at immediate, 1 month, and 6 months after operation. Gross observation and histological examination were conducted at 14 months to evaluate the repair and reconstruction efficacy.
Results
No dog died during operation of trachea reconstruction. One dog died of dyspnea at 37, 41, 55, 66, 140, and 274 days respectively because of anastomotic dehiscence and artificial trachea displacement; the other 10 dogs survived until 14 months. The fiberoptic bronchoscope examination, CT scan and three-dimensinal reconstruction showed that artificial tracheas were all in good location without twisting at immediate after operation; mild stenosis occurred and anastomoses had slight granulation in 6 dogs at 1 month; severe stenosis developed and anastomosis had more granulation in 1 dog and the other dogs were well alive without anastomotic stenosis at 6 months. At 14 months, gross observation revealed that outer surface of the artificial trachea were encapsulated by fibrous connective tissue in all of 10 dogs. Histological examination showed inflammatory infiltration and hyperplasia of fibrous tissue and no epithelium growth on the inner wall of the artificial trachea.
Conclusion
The new composite artificial trachea can be used to repair and reconstruct defect of the trachea for a short-term. Anastomotic infection and dehiscence are major complications and problems affecting long survival.
ObjectiveTo improve the knowledge of primary tracheobronchial lymphoma.MethodsTwo patients with primary tracheobronchial lymphoma admitted to First Affiliated Hospital Guangxi Medical University in 2013 and in 2016 were analyzed retrospectively, and related literatures were reviewed. Chinese National Knowledge Infrastructure, Wanfang database and VIP database were searched by using " trachea lymphoma” or " bronchus lymphoma” as keywords. Meanwhile, databases including PubMed, Ovid Medline and Embase database were retrieved with " Trachea” or " Bronchus” AND " Lymphoma” as keywords. Seventy-two cases of primary tracheobronchial lymphoma were reported, the clinical feature, imaging feature, pathological feature, treatment and prognosis of 72 cases were analyzed.ResultsThe two patients were both females. The chief complaints included cough and dyspnea. The tissue biopsy under bronchoscope was the main diagnostic method. On histopathology, one case was diagnosed grade B cell lymphoma, another was diagnosed mantle cell lymphomas. After chemotherapy, the symptoms were relieved and never relapsed in the follow-up period until October 2016. Literature review found 72 patients with primary tracheobronchial lymphoma with women being the majority (47 cases, 65.28%). The patients aged from16 to 82 years with a median age of 51 years, and nine cases (12.5%) of the patients aged from 16 to 30 years. The specific clinical symptoms were cough and dyspnea. Pulmonary function prompted obstructive dysfunction of pulmonary ventilation. The chest CT scan showed consolidation shadow in trachea and bronchus with or without pulmonary atelectasis. Neoplasms could be found by bronchoscopy. Mucosa-associated lymphoid tissue (MALT) lymphoma was the most common pathological characteristic (36.11%). Mantle cell lymphomas has not been reported currently.ConclusionsPrimary tracheobronchial lymphoma is one of the rare airway tumors. Its clinical features, imaging examinations and bronchoscopic characteristics are not specific, which can be easily confused with lung cancer. It also can cause life-threatening airway obstruction. The bronchoscopy play an important role in diagnosis of primary tracheobronchial lymphoma, while the diagnosis is confirmed by histopathological examination. The main pathology type is MALT lymphoma. The prognosis is good.
Objective To review the research advances of the tracheal prosthesis. Methods The articles concerned in recent years were extensively reviewed. Results There were still many arguments about the use of tracheal substitutes. Avariety of artificial trachea had been designed and assessed, but so far none of them had been satisfactory for clinical use. The failures were mainly due to their high mortality and incidence of complication such as prosthetic defluvium, granuloma formation, local infection, air leakage, anastomotic stenosis or obstruction. Conclusion The major causes of the poor effectiveness by the use of tracheal prosthesis are closely related to its biological compatibilities. The selected biomaterials and the design of prosthesis hold the key to a breakthrough in research and clinical use of tracheal prosthesis.
In tracheal resection and reconstruction, a technically demanding, complex, and high-risk procedure, management of the anastomotic site significantly impacts postoperative outcomes and long-term quality of life. However, comprehensive studies detailing perioperative anastomotic management strategies in tracheal reconstruction remain scarce. This review summarizes perioperative management strategies for tracheal reconstruction, covering preoperative assessment, surgical techniques, and other key aspects. It also highlights future research directions and challenges, aiming to provide clinicians with a systematic guide to perioperative management in tracheal reconstruction.
Objective To summarize our clinical experience of side-slide tracheoplasty in surgical management of bridging bronchus associated with congenital tracheal stenosis(CTS) and congenital heart disease (CHD).
Method We retrospectively analyzed the clinical data of 8 bridging bronchus patients associated with CTS and CHD underwent tracheoplasty in our hospital from January 2010 through June 2015. There were 3 males and 5 females at age of 19.6±9.1 months and weight of 9.9±5.4 kg in our hospital. It was found that main tracheal associated with intermediate bronchus stenosis in 4 patients. Complete tracheal rings or bronchial rings were identified in all cases. Less than 50% normal tracheal size was found in all patients. Correction of CHD and tracheoplasty were done under cardiopulmonary bypass at the same stage. The technique of side-slide tracheoplasty was used in all patients.
Results Average cardiopulmonary bypass time was 64.0±24.1 min. Average aortic clamp time was 14.0±18.1 min. No operative death occurred in hospital. The average duration of postoperative hospital stay was 20 d. Follow-up was completed in 8 patients. The duration of follow-up was 1 month to 5 years. Tracheal granulation occurred in one patient after six weeks of postoperation. The clinical symptoms improved significantly in the remaining patients.
Conclusions Bridging bronchi has special anatomical features. The technique of side-slide tracheoplasty can be used to correct bridging bronchus associated with CTS with satisfactory outcomes.
ObjectiveTo investigate the clinical features of primary tracheal or pulmonary malignant glomus tumor (MGT).MethodsA patient with primary tracheal MGT was reported. Wanfang, CNKI, Embase, Ovid, Cochrance and PubMed databases were searched with key words "tracheal malignant glomus tumor" and " pulmonary malignant glomus tumor” both in English and in Chinese for literature of primary tracheal or pulmonary MGT. Their clinical manifestations, imaging findings, bronchoscopic findings, pathological findings, especially immunohistochemical characteristics, diagnosis and differential diagnosis, treatment, and prognosis of primary tracheal or pulmonary MGT were summarized.ResultsThis male patient who manifested as cough, chest tightness, shortness of breath and dyspnea was diagnosed as tracheal MGT and received a treatment of radiofrequency ablation and cryotherapy under bronchoscopy. He refused to receive the chemotherapy and died after two months with a lung metastases. A total of 17 cases of primary tracheal or pulmonary MGT were retrieved in 16 articles, of which 5 were primary in the trachea and 12 were primary in the lung. Their clinical manifestations, imaging findings, and bronchoscopic findings were non-specific. The diagnosis relied on pathology, especially immunohistochemical staining. The preferred treatment of tracheal MGT may be surgical resection, the prognosis was acceptable. Treatment of lung MGT included lobectomy or airway interventional treatment and its prognosis was poor. The treatment of primary tracheal or pulmonary MGT needed early treatment. Because the curative effect of airway interventional treatment and chemotherapy was dubious, surgical plan should be first considered.ConclusionsBoth of primary tracheal and primary pulmonary MGT are rare. They usually lack specific clinical manifestations, laboratory tests, and imaging, and are easy to be misdiagnosis or miss diagnosis. The diagnosis can be confirmed by the results of biopsy for pathological analysis, especially by the immunohistochemical staining analysis. The treatment of tracheal and pulmonary MGT need further study.
