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1.
The epithelial cells of the colonic mucosa of the animal have proved impossible to culture using standard tissue culture techniques. Immortalization of adult colonic epithelial cells has been unsuccessful due to the lack of DNA synthesis in these cells once they are isolated from the tissue. Recently an unique transgenic mouse bearing a temperature sensitive mutant of the known immortalizing gene, SV40 large T has become available. The advantage of this mouse is that the SV40 large T gene is expressed in every cell. Active immortalizing protein is produced in each cell at the permissive temperature. We have used colonic mucosa from these mice to initiate cultures of epithelial cells from the colon of adult mice. The cells grow readily at the permissive temperature but die within 7 days at the non-permissive temperature. The methods used to develop these cultures are described. 相似文献
2.
大鼠自体异体表皮细胞悬液混合移植的实验研究 总被引:3,自引:2,他引:1
目的 探讨自、异体表皮细胞悬液混合移植技术在创面修复中的应用。 方法 30只大鼠随机配成 15对后 ,分成细胞悬液移植组 (A组 ,10对 )和细胞膜片移植组 (B组 ,5对 )。取每只大鼠全厚皮 ,分离表皮细胞 ,并根据配对情况按 1∶1的细胞比例混合 ,体外常规培养。 4d后收获A组混合细胞悬液 ,14d后收获B组混合细胞膜片。将此细胞悬液和膜片分别转移至A、B组相应供体大鼠的去全厚皮创面。随后A组每对大鼠的创面交叉覆盖配对方的异体全厚皮 ;B组创面覆盖胶原膜及“优妥”敷料。比较移植后 2~ 3周两组的创面修复情况。 结果 术后 2~ 3周 ,A组创面大多愈合 ,表面光滑 ,与皮下连接紧密。术后第 5天 ,B组创面部分细胞膜片脱落 ,部分成活 ,膜片成活的创面后期再次出现小创面 ,经久不愈。 结论 自、异体表皮细胞悬液混合移植是一种可行的、体内构建皮肤、修复创面的方法。 相似文献
3.
烧伤血清刺激对大鼠肠上皮细胞结构和粘弹性的影响 总被引:1,自引:0,他引:1
目的 动态观察烧伤血清对体外肠上皮细胞 (IEC)骨架和细胞生物力学 (粘弹性 )的影响。 方法 培养大鼠肠上皮细胞株IEC 6 ,用烧伤血清刺激后 ,通过细胞骨架免疫组化、细胞ELISA法定量分析以及粘弹性测定技术 ,动态观察IEC致伤前后的变化。 结果 IEC在烧伤血清作用早期 ,骨架蛋白的表达即明显降低 ,微丝、微管蛋白阳性信号减弱 ,细胞粘弹性下降。 结论 细胞骨架的损伤可引起细胞脆性增加、粘弹性下降 ,导致细胞生物力学特性的改变。这种变化 ,可能直接参与烧伤后肠上皮细胞损伤的发生。 相似文献
4.
The ontogeny of circulating hemocytes and tumor cells in mollusks has been approached using monoclonal antibodies to normal cells. A monoclonal antibody, previously shown to identify an adhesion related protein (p130), has been used to define the reactivity of cells in tissues from normal soft-shell clams (Mya arenaria) and soft-shell clams with leukemia. Using immunoperoxidase technology, we have determined that hemocytes, connective tissue cells, and a subset of leukemia cells that are adherent share a cross-reactive epitope with cilia. 相似文献
5.
J. B. Matthews A. Pitigala-Arachchi I. J. Crane C. Scully S. S. Prime 《Virchows Archiv : an international journal of pathology》1988,413(6):521-528
Summary The development of oral epithelial expression of Ia antigens and its relationship to the presence of IL-2r+ (CD25+) cells was investigated in rats treated with the water soluble carcinogen 4-nitroquinoline-N-oxide (4NQO). Acetone fixed frozen sections of the palate and tongue were stained using an indirect immunoperoxidase technique and monoclonal antibodies to rat Ia (I-A & I-E) and IL-2 receptor. After 4 weeks 4NQO treatment all rats expressed oral epithelial Ia but thereafter (2–9 months) expression was present in only 20–40% of animals. Epithelial expression of Ia by histologically normal, dysplastic and neoplastic epithelium was always associated with the presence of an underlying inflammatory cell infiltrate containing CD25+ cells. Overall there were significantly more CD25+ cells in tissue specimens containing Ia+ epithelium compared with Ia– epithelium. Furthermore, during the first 4 weeks of carcinogen treatment, a significant positive correlation was found between the CD25+ cell density and occurrence of focal epithelial Ia expression. These results, together with analysis of the T cell, NK cell, macrophage and B cell content of the infiltrates induced by 4NQO, suggest that the CD25+ cells represent activated T cells. Thus, our results in this experimental model are consistent with the idea that epithelial expression of Ia is the result of production of IFN- by locally activated T cells. 相似文献
6.
目的:观察Nd:YAG激光治疗上皮植入性虹膜囊肿的疗效。方法:治疗前详细了解囊肿与周围组织的关系,首先激穿囊肿前壁,使腔内液体引流,然后降低能量,照射囊肿后壁及周围组织,以尽可能破坏上皮细胞,减少复发。激光治疗单脉冲能量为0.4MJ,每次治疗总量为20~35MJ。结果:所有治疗眼的视力均有不同程度提高。经术后6个月~1年的随访观察,未见明显复发。结论:激光治疗上皮植入性虹膜囊肿,既可破坏囊壁的上皮细胞,又可避免和减少囊肿邻近组织的损伤及反应,以尽可能多地保留和恢复有效视功能,以避免患者因再次手术所带来的痛苦,疗效满意 相似文献
7.
The fate of ocular surface epithelial cells in response to injury of the cornea was examined. Corneal epithelial cells were labeled during DNA synthesis with [3H]thymidine 1 h prior to wounding. A 3-mm diameter epithelial defect was made in the center of the rat cornea, with the basement membrane remaining intact. Within 12 h of abrasion, labeled cells were detected in the regenerating surface. At 18 h, there was a 2.7- and 17-fold increase of labeled basal and suprabasal cells, respectively, in the epithelium adjacent to the wound, and at 24 and 30 h there was an excessive number of cell layers (up to 7) at the margin of the abrasion. Re-epithelialization progressed as a gradient of cell layers that became diminished towards the center of the wound. Completion of layers 1, 2, 3, and 4 were recorded at 24, 30, 36, and 72 h, respectively. No changes in the labeling index of the limbus or conjunctiva were noted. These results suggest that processes of centripetal and vertical migration, as well as events related to cell division, in the uninjured corneal surface are not impeded by wounding of the corneal epithelium. However, wound healing appears to require cells with a basal phenotype, presumably because of this cell type's migratory capability. 相似文献
8.
K. R. Clark J. A. Kirby N. Baker A. L. Givan B. K. Shenton G. Proud T. W. J. Lennard R. M. R. Taylor 《Transplant international》1991,4(4):210-214
A novel in vitro assay of renal epithelium tight junction function was used to assess the efficacy with which rabbit anti-thymocyte globulin (ATG) blocks epithelium damage mediated by lymphokine-activated killer (LAK) cells. It was found that LAK cells lysed renal epithelial cells poorly in standard chromium-release assays but that they caused a rapid, and almost total, reduction in trans-epithelium monolayer resistance, indicating tight junction failure and, hence, loss of tissue function. LAK cell-mediated cytolysis of the sensitive K562 cell line was completely blocked in the presence of ATG at a concentration of 200 g/ml. Addition of ATG at this concentration to damaged renal cell monolayers in the presence of LAK cells allowed the trans-monolayer resistance to recover rapidly to levels approaching the values recorded before initial addition of LAK cells. On this basis it seems likely that the rapid restoration of renal function frequently observed after appropriate rescue therapy during episodes of acute rejection may reflect subtle changes in tissue function rather than recovery from widespread graft cell cytolysis. 相似文献
9.
Toll-like receptor (TLR) is an important pattern recognition receptor (PRR) which participates in innate immunity and regulates adaptive immunity. TLR can be expressed in immune cells and malignant tumors recognize conservative molecular structure, mediate response of inflammation, tissue injury and repair, which plays an important role in the process of tumor. Research results about some molecules and signal pathways of TLR demonstrate that it can act anti or pro-tumor dual functions, which has an extensive prospects in prevention and treatment of tumor. 相似文献
10.