不同剂量碘对大鼠胸腺CK19阳性上皮细胞的影响

目的研究摄入不同剂量碘化钾后胸腺细胞角蛋白19阳性(CK19 )上皮细胞的变化。方法取断乳后1个月的Wistar大鼠,随机分为6组:低碘组、适碘组、5倍碘组、10倍碘组、50倍碘组、100倍碘组,分别给予不同浓度的碘化钾。饲养6个月后,测定血清甲状腺激素水平,胸腺上皮细胞免疫组化染色。结果与适碘组相比,100倍碘组和低碘组的T4、T3和rT3均显著降低(P<0.05),并且可见这两组的胸腺上皮细胞局限性增生;50倍碘组、100倍碘组和低碘组胸腺CK19 上皮细胞的体密度和面数密度显著降低(P<0.01);其余各组未见明显异常。结论长时间的摄碘异常(碘缺乏、碘过量)可使大鼠甲状腺激素水平降低,从而导致胸腺CK19 上皮细胞减少,胸腺退化。     

甲状腺激素缺乏对大鼠胸腺CK19阳性上皮细胞的影响

目的探讨甲状腺激素缺乏对大鼠胸腺CK19^ 上皮细胞的影响。方法将断乳1月龄的Wistar大鼠分为2组：正常组饲以正常饲料，饮用自来水；低碘组饲以低碘饲料，饮用去离子水。实验3个月及6个月后，测定各组大鼠的胸腺指数、血清甲状腺激素及胸腺CK19^ 上皮细胞的体密度和面数密度。结果实验3个月后，低碘组大鼠的胸腺指数、T4显著降低，而CK19^ 上皮细胞的体密度和面数密度未见明显变化；实验6个月后，低碘组大鼠的T3、T4显著降低，胸腺CK19^ 上皮细胞的体密度的面数密度显著降低。结论甲状腺激素缺乏可使大鼠胸腺严重退化，CK19^ 上皮细胞减少。     

低碘大鼠胸腺上皮细胞的异质性研究

目的 探讨胸腺上皮细胞的异质性及甲状腺功能降低时大鼠胸腺上皮细胞的变化。方法 将断乳后1月的Wistar大鼠分为2组：正常组饲以正常饲料，饮用自来水；低碘组饲以低碘饲料，饮用去离子水。饲养3个月后测定各组大鼠血清甲状腺素及胸腺指数，同时对大鼠胸腺进行透射电镜观察。结果 低碘组大鼠血清甲状腺激素及胸腺指数显著降低。胸腺上皮细胞发生了3种变化：(1)细胞角蛋白增多；(2)囊泡增大和(或)小泡增多；(3)细胞降解。结论 不同部位的胸腺上皮细胞对甲状腺功能低下的反应不同。     

艾迪注射液联合化疗对中晚期NSCLC患者外周血肿瘤细胞CK19-mRNA表达的影响

目的探讨艾迪注射液联合化疗对中晚期非小细胞肺癌（NSDLD）患者外周血肿瘤细胞细胞角蛋白（CK19）-mRNA表达的影响。方法将40例中晚期NSCLC患者随机分为两组,观察组22例用紫杉醇、顺铂化疗＋艾迪注射液治疗,对照组18例用紫杉醇、顺铂化疗。用逆转录聚合酶链式反应技术检测两组化疗2周期后外周血肿瘤细胞CK19-mRNA相对表达量,并观察其疗效及生存期。结果两组治疗前后比较、观察组与对照组比较,CK19-mRNA相对表达量均有统计学差异（P均〈0．05）;观察组化疗有效率及生存率均优于对照组（P〈0．05）。结论艾迪注射液可能通过下调NSDLD患者外周血肿瘤细胞CK19-mRNA表达量而起到化疗增效的作用。     

不同剂量碘摄入对缺碘大鼠甲状腺肿复原的影响

目的了解不同剂量碘摄入对甲状腺肿复原的影响。方法将Wistar大鼠复制成低碘性甲状腺肿模型后，随机分为适、中、高不同剂量的补碘组及碘油组进行补碘干预实验，在开始后的1，2，4，8，12，24周时分别测量甲状腺湿重、血清激素及甲状腺抗氧化能力。结果各补碘组在1周后甲状腺重量较低碘组(LI)均有明显降低，血清TT4明显增高，但不同补碘组之间无明显差异；血清TT4与LI组无明显差别。各补碘组甲状腺抗氧化能力均较稳定，始终维持在补碘1周时的水平；而LI组谷胱甘肽过氧化物酶(GSH-Px)活性在24周时明显降低，丙二醛(MDA)含量显著升高。结论补充不同剂量的碘对甲状腺肿的复原、甲状腺激素水平的改善以及抗氧化能力的提高都有显著的效力。本实验未发现高剂量碘摄入给甲状腺组织带来明显负面影响。     

低碘和高碘对大鼠甲状腺细胞凋亡的影响

目的 研究低碘和高碘对大鼠甲状腺细胞凋亡的影响。方法 利用病区的低碘粮食喂养大鼠，同时饮用不同质量浓度的加碘水，复制低碘和高碘动物模型，于20周后在光、电镜下观察甲状腺形态结构改变，原位末端标记方法对甲状腺细胞凋亡进行检测。结果 与对照组相比，低碘和高碘组甲状腺凋亡细胞数明显增多。结论 低碘和高碘均诱发大鼠甲状腺细胞凋亡，进而调节甲状腺的形态结构和功能。其中以低碘组作用明显，提示细胞凋亡过度是引起低碘和高碘性甲状腺功能低下的重要原因。     

过渡型CK19阳性表达细胞的研究

目的探讨慢性乙型肝炎患者肝组织过渡型CK19阳性表达细胞与肝癌前病变的关系。方法用LSAB免疫组织化学染色方法观察慢性乙型肝炎患者肝组织CK19的表达，每3个月对患者检查B超和血清甲胎蛋白，随访至1年。结果肝组织出现卵圆细胞分化为肝细胞的过渡型CK19阳性表达细胞的患者，大多数出现血清甲胎蛋白的明显升高。随访至1年，有1例患者出现小肝癌，1例出现肝实质低回声结节。结论过渡型CK19阳性表达细胞有可能作为一种新的肝癌前病变的病理学标志。     

扁桃体鳞状细胞癌中CK7 CK19和p16的表达关系研究

目的 分析细胞角蛋白7(CK7)、细胞角蛋白19(CK19)和p16INK4a蛋白(p16)在扁桃体鳞状细胞癌(TSCC)组织及癌周隐窝上皮和表面上皮中的表达关系,探讨其在人乳头状瘤病毒(HPV)感染相关扁桃体癌变机制中的作用.方法 选择2015-07～2018-01广西医科大学第一附属医院耳鼻喉头颈外科收治的17例T...     

妊娠期大鼠不同程度碘缺乏对胎鼠碘代谢和甲状腺功能的影响

目的 研究妊娠期大鼠不同程度碘缺乏对胎鼠碘代谢和甲状腺功能的影响.方法 40只Wistar雌性大鼠按体质量随机分为4组,每组10只,均食用低碘饲料(含碘量为50μg/kg);重、中、轻度缺碘(SID、MoID、MiID)组和正常碘(NI)组饮用含不同剂量碘化钾(0、54.9、163.8、381.7μg/L)的自来水(含碘量为8μg/L),每日总碘供给量分别为1.24、2.50、5.00、10.00μg.喂养3月后与按NI组条件饲养的Wistar雄性鼠交配,以妊娠20 d孕鼠和胎鼠为研究对象,过硫酸铵消化砷铈催化分光光度法测定孕鼠尿碘和胎鼠羊水含碘量,碱灰化砷铈催化分光光度法测定孕鼠血碘和胎盘组织含碘量,化学发光法测定孕鼠血清及胎鼠羊水甲状腺激素水平,检测并观察孕鼠和胎鼠的甲状腺质量及大体变化.结果 ①孕鼠尿碘、血碘,胎鼠羊水碘均随碘供给量减少呈降低趋势.NI、MiID、MoID、SID组孕鼠尿碘中位数分别为353.7、115.9、26.9、0μg/L,组间比较差异有统计学意义(χ2=32.884,P<0.01);MoID、SID组[(29.4±18.6)、(11.7±7.0)μg/L]孕鼠血碘明显低于NI组[(49.1±23.0)μg/L,P<0.05或<0.01).与NI组[(65.4±41.2)μg/L,(0.35±0.14)μg/g]比较,MiID、MoID、SID组胎鼠羊水碘[(48.3±23.1)、(29.2±14.7)、(19.5±6.7)μg/L]呈降低趋势,胎盘组织碘[(0.57±0.26)、(0.53±0.34)、(0.53±0.15)μg/g]呈升高趋势,但组间比较差异均无统计学意义(P>0.05).②SID组孕鼠血清TT4[(14.3±4.1)mmol/L]和FT4[(10.8±3.6)pmol/L]明显低于NI组[(28.4±19.3)nmol/L,(20.2±8.0)pmol/L,P<0.05或<0.01],而FT3/FT4比值(0.34±0.16),甲状腺绝对质量[(48.4±22.7)mg]和相对质量[(144±76)mg/kg]明显高于NI组[(0.16±0.02)、(19.5±3.1)mg,(66±10)mg/kg,P<0.01];MiID、MoID组TT4[(25.5±13.1)、(22.1±6.1)nmoL/L]和FT4[(18.6±8.4)、(18.5±4.1)pmol/L]与NI组比较,有降低趋势,FT3/FT4比值(0.17±0.06、0.19±0.04),甲状腺绝对质量[(25.0±8.9)、(27.0±5.7)mg]和相对质量[(78±25)、(84±19)mg/kg]与NI组比较,有增高趋势,但组间比较差异均无统计学意义(P>0.05);SID组孕鼠甲状腺明显充血肿大,MiID、MoID组轻度肿大.③SID组胎鼠羊水FT4[(1.07±0.87)pmol/L]低于NI组[(2.38±1.55)pmoVL],FT3/FT4比值(1.96±0.61)高于NI组(0.50±0.18),组间比较差异均有统计学意义(P<0.05或<0.01);MiID、MoID组FT4[(2.77±0.90)、(2.35±0.76)pmol/L]、FT3/FT4比值(0.46±0.15、0.61±0.21)与NI组比较,差异均无统计学意义(P>0.05);SID组胎鼠甲状腺有明显充血肿大,MiID、MoID组仅见轻度充血,其大小与NI组相似.结论 重度碘缺乏使孕鼠及其胎鼠均发生了明显甲状腺功能减退症,而轻度碘缺乏通过代偿可使胎儿甲状腺激素维持正常水平,中度碘缺乏对母亲和胎儿均有不同程度的负面影响.     

检测老年胃癌患者腹腔灌洗液CK19、CEA mRNA的临床意义

目的 观察细巢式逆RT-PCR检测老年胃癌患者腹腔冲洗液瘤细胞胞角蛋白19(CK19)、癌胚抗原(CEA)的临床价值.方法 收集45例进展期老年胃癌和8例胃良性病变患者腹腔冲洗液200 ml,其中100 ml行RT-PCR检测CK19、CEA mRNA,另100 ml用于HE染色细胞学检查,胃癌细胞SGC7901为阳性对照.结果 45例老年胃癌病人腹腔冲洗液中CK19 mRNA的阳性表达率为55.6%(25/45);CEA mRNA的阳性表达率为51.1%(23/45);CK19、CEA mRNA的联合检测阳性率为62.2%(28/45).细胞病理学检查45例胃癌病人有8例腹腔冲洗液中发现肿瘤细胞,阳性率为17.8%(8/45),且此8例CK19、CEA mRNA检测结果均为阳性.CK19、CEA mRNA阳性率与肿瘤胃壁浆膜受侵、淋巴结转移和胃癌分期明显相关(P＜0.05).结论 腹腔冲洗液中CK19、CEA mRNA检测胃癌细胞敏感性高.初步临床观察显示此方法对于早期诊断胃癌患者腹腔种植有一定价值.     

Human thymic epithelial cells produce interleukin-3

Interleukin-3 (IL-3) is a hematopoietic growth factor suggested to be produced by activated T lymphocytes. Meanwhile, supernatants from human thymic stroma could promote the proliferation of myeloid stem cells. Thus, we investigated whether IL-3 accounts for this activity. Therefore, human thymic epithelial cells (TEC), fibroblasts, and adherent cells were isolated, and their culture supernatants assayed for myeloid colony promotion. Only supernatants from thymic epithelial cells supported colony-forming unit growth in semisolid media. This effect decreased following anti-IL-3 monoclonal antibody addition to these cultures. Furthermore, in situ hybridization showed the presence of IL-3 mRNA in epithelial cells. Effect of TEC culture conditions on IL-3 production by these cells was also studied. Together, these data show that IL-3 production is not the exclusive property of human activated T lymphocytes.     

Regenerative capacity of adult cortical thymic epithelial cells

Involution of the thymus is accompanied by a decline in the number of thymic epithelial cells (TECs) and a severely restricted peripheral repertoire of T-cell specificities. TECs are essential for T-cell differentiation; they originate from a bipotent progenitor that gives rise to cells of cortical (cTEC) and medullary (mTEC) phenotypes, via compartment-specific progenitors. Upon acute selective near-total ablation during embryogenesis, regeneration of TECs fails, suggesting that losses from the pool of TEC progenitors are not compensated. However, it is unclear whether this is also true for the compartment-specific progenitors. The decline of cTECs is a prominent feature of thymic involution. Because cTECs support early stages of T-cell development and hence determine the overall lymphopoietic capacity of the thymus, it is possible that the lack of sustained regenerative capacity of cTEC progenitor cells underlies the process of thymic involution. Here, we examine this hypothesis by cell-type-specific conditional ablation of cTECs. Expression of the human diphtheria toxin receptor (hDTR) gene under the regulatory influence of the chemokine receptor Ccx-ckr1 gene renders cTECs sensitive to the cytotoxic effects of diphtheria toxin (DT). As expected, DT treatment of preadolescent and adult mice led to a dramatic loss of cTECs, accompanied by a rapid demise of immature thymocytes. Unexpectedly, however, the cTEC compartment regenerated after cessation of treatment, accompanied by the restoration of T-cell development. These findings provide the basis for the development of targeted interventions unlocking the latent regenerative potential of cTECs to counter thymic involution.     

Wnt4 regulates thymic cellularity through the expansion of thymic epithelial cells and early thymic progenitors

Thymus atrophy is the most common immunopathology in humans, and its occurrence is hastened by several factors that coalesce in patients receiving chemotherapy and most of all in recipients of hematopoietic cell transplantation. We have shown previously that posthematopoietic cell transplantation thymic function was improved by retroviral overexpression of Wnt4 in donor hematopoietic cells. Here, by using both conventional and conditional null mutant mice, we show that Wnt4 regulates steady-state thymic cellularity by a thymic epithelial cell (TEC)-dependent mechanism. The absence of Wnt4 suppressed fetal and postnatal thymic expansion and resulted in decreased TEC numbers, an alteration of the medullary-to-cortical TEC ratio, and a disproportionate loss of the most immature cKit(hi) thymocyte precursors. Wnt4 also is implicated in the maintenance of adult thymopoiesis, although the impact of its deletion once thymic involution has been initiated is more subtle. Together, our results show that Wnt4 controls thymic size by modulating TEC expansion and the earliest, TEC-dependent steps of thymocyte development both in the fetal and postnatal thymus. Wnt4 and its downstream signaling pathways could thus represent interesting candidates to improve thymic output in subjects with thymic atrophy.     

TGF-beta signaling in thymic epithelial cells regulates thymic involution and postirradiation reconstitution

The thymus constitutes the primary lymphoid organ responsible for the generation of naive T cells. Its stromal compartment is largely composed of a scaffold of different subsets of epithelial cells that provide soluble and membrane-bound molecules essential for thymocyte maturation and selection. With senescence, a steady decline in the thymic output of T cells has been observed. Numeric and qualitative changes in the stromal compartment of the thymus resulting in reduced thymopoietic capacity have been suggested to account for this physiologic process. The precise cellular and molecular mechanisms underlying thymic senescence are, however, only incompletely understood. Here, we demonstrate that TGF-β signaling in thymic epithelial cells exerts a direct influence on the cell's capacity to support thymopoiesis in the aged mouse as the physiologic process of thymic senescence is mitigated in mice deficient for the expression of TGF-βRII on thymic epithelial cells. Moreover, TGF-β signaling in these stromal cells transiently hinders the early phase of thymic reconstitution after myeloablative conditioning and hematopoietic stem cell transplantation. Hence, inhibition of TGF-β signaling decelerates the process of age-related thymic involution and may hasten the reconstitution of regular thymopoiesis after hematopoietic stem cell transplantation.     

Functional Fas expression in human thymic epithelial cells

Fas, a cell surface receptor, can induce apoptosis after cross-linking with its ligand. We report that Fas antigen is constitutively expressed in medullary epithelial cells of the human thymus. Expression is decreased in cultured thymic epithelial cells (TEC), similarly to HLA-DR antigen. TEC are resistant to anti-Fas-induced apoptosis after 4 days of primary culture, and this resistance is reversed by concomitant addition of cycloheximide. Cycloheximide also downregulated the expression of Fas-associated phosphatase-1, which has been found to inhibit Fas-induced apoptosis. This phosphatase could be involved in the resistance to Fas-induced apoptosis observed on day 4 of TEC culture. When TEC were subcultured after 10 to 13 days of primary culture, exposure to interleukin-1-beta, tumor necrosis factor-alpha, and interferon-gamma, alone or together, reinduced Fas mRNA and protein expression. In coculture with activated thymocytes, TEC also upregulated Fas protein expression. Cytokine-activated TEC became sensitive to apoptosis induced by an agonistic anti-Fas antibody. This apoptosis was inhibited by Z-VAD-fmk but not by Z-DEVD-fmk and DEVDase activity was slightly increased in Fas-stimulated TEC, suggesting that DEVDase activity is not sufficient to induce TEC apoptosis. Taken together, these data show that the Fas receptor is expressed in medullary epithelial cells of the human thymus and is able to induce apoptosis.     

氟对小鼠胸腺及上皮细胞形态与功能的影响

目的研究氟化物对胸腺上皮细胞的毒性作用及对胸腺细胞发育的影响,探讨其作用机制。方法采用小鼠胸腺上皮细胞原代体外培养及与胸腺细胞混合培养技术,观察不同剂量氟化钠(NaF)对小鼠胸腺上皮细胞形态与功能的损伤情况及胸腺细胞在NaF处理的小鼠胸腺上皮细胞环境中的生长发育状况。结果染氟组可见小鼠胸腺上皮细胞胞体变圆,折光性增强,胞浆内有空泡形成,小鼠胸腺上皮细胞培养基中乳酸脱氢酶(LDH)活性增强,胸腺上皮细胞合成DNA和蛋白质的能力降低,白细胞介素1(IL-1)分泌量减少,并呈一定的剂量反应关系。不同剂量NaF处理的小鼠胸腺上皮细胞与新鲜的胸腺细胞混合培养,随着染氟剂量的增加,胸腺细胞摄取3H-Tdr和3H-Leu的能力降低,活细胞数目逐渐减少。结论高氟能够直接损伤小鼠胸腺上皮细胞、破坏胸腺微环境,进而导致胸腺细胞发育障碍,影响免疫功能。