Related Study On Androgen-Secreting Tissue Construction For Test's Shape With Tissue Engineering Technique

BackgroundBecause of congenital disease, environmental pollution, anabatic working pressure and increased aging population, the morbidity of hypoandrogenism increased greatly year after year. Regretfully, there was no safety and affective therapy method aimed at this disease. The testes are very important for an adult man. Because 95% androgen of the body originally secreted by testis Leydig cells (LCs), some researchers attempt to treat the hypoandrogenism by allogeneic testis transplantation and LC transplantation. But allogeneic testis transplantation had the disadvantage of graft rejection, losing testosterone secreting function rapidly and ethnical problems. And, LC transplantation had the disadvantage of limited source, losing function and short of appropriate growth microenvironment. These disadvantages limited their generalization in clinic. So, seeking of a new kind of method to produce endogenous androgen and be in response to the physiologic regulation of the body would become a new way to solve this kind of disease. The development of tissue engineering provided the possibility of reconstruction of this kind of tissue.At present, the report about androgen-secreting tissue construction was relatively limited. Although some studys primarily approved the technical feasibility of constructing the androgen-secreting tissue with TE technique, while after transplanted into bodies, the hormone level maintained of construct tisssue and the structure but it were not the shape of testis for the shape of transplanted structure and the cells transplanted into bodies did not been labelled ,How could we resolve it ?With relation to the above question, this study aimed to resolve the problem of the cells labeled and to study the possible to form a tissue with testis shape and the long-term outcome of the construct after transplanted into syngenic rats.ObjectiveBy the research of biological characteristic of seed cells, this study aimed at exploring the possibility of labeled the co-culture cells with QDs and them used for androgen-secreting tissue construction and furthermore, to construct the androgen-secreting tissue which would maintain the secreting ability for longer times and with testis shape and structure in vivo and in vitro of syngenic rats. Methods1. Co-culture of testes somatic cells: testes tissue was digested by collagenase, filtrated by200 mesh screen, centrifuged and cultured for 24 hours. All cells got by attachment method were co-cultured testes somatic cells.2. Labell the cells with QDs3. Preparation of castrated and transplanted rat model: cut bilateral testis completely and maintain the epididymides as the castrated rat model.4. Transplantation into syngenic castrated rats and function evaluation of the construct: According to the type of transplant, the rat models were divided into 4 groups, (1) castrated alone (control group); (2) co-culture somatic cells+ PGA/PLA group; (3) co-cultured somatic cells +Medpor+ PGA/PLA group. (4)Medpor+PGA\PLA group. Gathering passage one co-cultured testes somatic cells, and then seeded into the precast PGA/PLA scaffold and Medpor+PGA\PLA scaffold respectively by the same cell density, after 2 hours, the constructs were transplanted into the perididymis spatium of the corresponding groups. Observe the tissue formation, PGA/PLA degradation and the vascularization of the construct tissue. Assay the serum testeosterone level of the transplanted rats by heart puncture.ResultsPartâ… The cells fluorescent labels:The co-cultured testis somatic cells labeled with QDs were easy to label. The quantum dots in the cells were brighter, more stable and do not leak out of cells. The quantum dots in the cells were inherited by the daughter cells.Partâ…¡The androgen-secreting tissue construction with testis shape1. In vivo construction and biological evaluation of explants: At 3 month after transplantation, the construct of PGA\PLA+cells group could not maintain the shape and volume. The construct of Medpor+PGA\PLA+cells group still had the original shape and size, with tenacious testosterone. The section of them showed good and homogeneous tissue formation. Histology showed that the transplant was mainly made up of inter-fibrous interval and nested cell mass with good vascularization in it. At 6 month, the construct of PGA\PLA+cells group was smaller than that of Medpor+PGA\PLA+cells group. At 6 month, the transplant was difficult to maintain high level testosterone while in Medpore+PGA\PLA+cells groups, the transplant still had good shape. After transplanted 12 weeks, the serum testosterone of these two groups were high than that of simple castrated groups (P<0.05), Serum testosterone level of PGA\PLA+cells groups could maintained till 24 weeks after transplantation, and higher than that of simple castrated groups and Medpor+PGA\PLA+cells groups(P<0.05).ConclusionThe research result showed: And QDs labeling opened up new possibilities for long-term monitoring of the co-cultured testis somatic cells. We established an improved LC isolation method, which could meet the request of seed cells with large quantity and good function. The co-cultured somatic cells with the testis shape cell-scaffold construct had good testosterone secreting ability and it could maintain the secreting ability for longer times(3 months) in syngenic Wister rats.