新生大鼠胰腺nestin阳性细胞的体外分离、培养和分化的研究

目的探索新生大鼠胰腺nestin阳性细胞体外分离、培养并使之形成类胰岛样细胞团的方法。方法应用胶原酶消化新生大鼠胰腺,将消化的组织碎片培养形成类胰岛样细胞团后传代。免疫荧光细胞化学法检测贴壁细胞胰岛素、胰高血糖素及nestin的表达。RT-PCR检测培养1周的贴壁细胞nestin及细胞角蛋白(CK19)的表达。结果在pH 7．6条件下培养24-36 h有部分细胞贴壁生长,改用pH 7．4无血清RPMI 1640培养液培养18-24 d可形成类胰岛样细胞团,传代后可有单层细胞生长。培养24～36 h的贴壁细胞nestin呈阳性,但胰岛素、胰高血糖素阴性,形成的类胰岛样细胞团传代后24 h胰岛素、胰高血糖素呈阳性。培养1周的单层细胞经RT-PCR扩增获得nestin 片段,但未获得CK19相应的片段。结论类胰岛样细胞团传代培养后可表达胰岛素、胰高血糖素; 胰腺nestin阳性细胞具有胰岛干细胞的特点。     

糖尿病小鼠胰腺干细胞转分化为胰岛样细胞

目的 观察链脲佐菌素所致糖尿病小鼠胰腺干细胞是否能转分化为胰岛样细胞.方法 以链脲佐菌素建立糖尿病小鼠模型,分离培养其胰腺导管上皮细胞,经体外扩增及诱导培养后,以细胞免疫化学方法检测PDX1表达,行STZ染色和葡萄糖刺激的胰岛素释放试验鉴定其功能.结果 糖尿病小鼠胰腺干细胞经体外培养和诱导分化后,PDX1阳性,并形成胰岛样细胞团;胰岛样细胞对高糖刺激(15.0 mmol/L)的胰岛素释放较低糖(5.6 mmol/L)时增加了1.4倍(37.2±11.2比25.9±7.6,t =2.830,P＜0.05),DTZ染色阳性.结论 链脲佐菌素所致糖尿病小鼠胰腺干细胞在体外培养条件下可转分化为胰岛素分泌细胞.     

损伤胰腺组织提取液诱导大鼠骨髓间充质干细胞向胰岛样细胞分化的实验研究

目的：探讨胰岛损伤的胰腺组织提取液诱导大鼠骨髓间充质干细胞向胰岛素样细胞分化的作用.方法：通过大鼠腹腔注射链脲佐菌素（STZ）建立1型糖尿病模型,6 d后剥离胰腺提取胰腺组织提取液,与SD大鼠骨髓间充质干细胞共同培养18 d,体外诱导骨髓间充质干细胞向胰岛素分泌细胞分化,RT-PCR法检测诱导分化后细胞的胰岛细胞相关基因的表达,葡萄糖刺激胰岛素释放实验检测诱导后细胞在高糖作用下分泌胰岛素的功能.结果：经损伤胰腺组织提取液诱导后,间充质干细胞在形态上由梭形变成多边、不规则形,且逐渐聚集成岛状.免疫荧光检测诱导细胞的胰岛素表达呈阳性,RT-PCR检测诱导细胞表达胰岛素1（Ins1）、胰岛素2（Ins2）、葡萄糖转运子2（Glut-2）、神经源素3（Ngn3）、胰腺十二指肠同源盒1（Pdx1）、同源框蛋白（Isl-1）及脑神经源性分化因子（NeuroD）等胰岛相关基因,且具备高糖诱导促进胰岛素分泌的功能.结论：在损伤胰腺组织提取液诱导下,骨髓间充质干细胞分化为胰岛样细胞,并且具有表达胰岛相关基因和胰岛素分泌功能.     

黄芩苷诱导大鼠骨髓间充质干细胞体外分化为胰岛素分泌细胞

目的 体外诱导大鼠骨髓间质干细胞（BMSCs）分化为胰岛样细胞。方法 采用分步法体外诱导后，间接免疫荧光法鉴定诱导前后细胞nestin、胰岛素蛋白表达；RT-PCR法检测诱导前后胰岛转录因子mRNA表达；ELISA检测诱导后细胞葡萄糖刺激的胰岛素分泌。结果 免疫荧光染色显示诱导5h，nestin阳性细胞为（44．6±7．3）％。诱导24h，nestin阳性细胞增至（61．8±8．4）％。此后，nestin阳性细胞数目开始下降，诱导第14天后，nestin表达基本消失；同时诱导后的细胞可以表达胰岛素蛋白。另一方面，RT-PCR结果显示诱导后细胞可以表达胰岛素-1、葡萄糖转运子-2及其转录因子mRNA。ELISA结果显示不同浓度的葡萄糖刺激的胰岛素分泌量不同，5mmol／L和25mmol／L葡萄糖刺激的胰岛素分泌量分别为（25．53±6．49）和（53．26±7．56）mU／L，而诱导前MSCs不具备上述特点。结论 大鼠BMSCs体外可以诱导成为胰岛素分泌细胞。     

人表皮干细胞的体外分离和培养

目的:建立人表皮干细胞的体外分离和培养体系的方法,探索表皮干细胞体外大量扩增的途径.方法:采用0.375%的DispaseⅡ和0.05%胰蛋白酶二步酶消化法从小儿包皮中分离表皮细胞,采用MTF法筛选表皮细胞基础培养基和表皮细胞生长因子(epidermal growthfactor,EGF)的最适浓度,建立表皮干细胞培养的干预体系.逐日观察培养的细胞呈表皮干细胞样的形态,免疫组化方法检测β1整合素和角蛋白19的表达.结果:以表皮细胞数量和活性作指标,不同浓度EGF干预条件细胞活性不同,以15 ng/mL EGF的无血清SFM培养液为最适培养液,可使细胞呈表皮干细胞克隆样生长,β1整合素和角蛋白19表皮干细胞活性表达呈阳性.结论:采用0.375%的Dispase Ⅱ和0.05%胰蛋白酶二步酶消化法从小儿包皮中分离表皮细胞,以15 ng/mL EGF的无血清SFM培养液培养,此方法是一种简便、快速、经济的表皮干细胞分离和培养的方法.     

从人胚胎胰腺中分离获得巢蛋白表达阳性的细胞

目的 探讨从人胚胎胰腺组织分离巢蛋白（Nestin)阳性细胞并进行体外传代培养的方法。方法 取引产的16、18、20周人胚胎胰腺组织，分离胰岛样细胞簇（Ialet-like cell clusters,ICCs），进行体外培养。用免疫组织化学和逆转录-聚合酶链反应（RT-PCR）方法检测巢蛋白、胰十二指肠同源盒基因-1（Pancreatic and duodenal bomeobox gene-1,PDX-1/IPF-1)以及胰岛内分泌激素胰岛素和胰升糖素（Glucagon)的表达。结果 ICCs经体外培养可获得巢蛋白表达阳性细胞，这种细胞可进一步形成球状细胞簇，除有巢蛋白阳性细胞外，还有PDX-1，胰岛素和胰升糖素表达阳性的细胞。并且细胞可连续传代，结论 从人胚胎胰腺组织中可分离获得巢蛋白表达阳性细胞，这种细胞可在体外增殖并有向胰岛内分泌细胞分化的能力。     

巢蛋白和神经元素3在人胚胎胰腺中的表达和分布

目的探讨胰腺干细胞标志巢蛋白（nestin）和神经元素3（Ngn3）在人胚胎胰腺组织中的表达及其与内分泌细胞、导管细胞和外分泌细胞标志的共表达情况。方法以因病理因素行药物引产的12周-14周前人胚胎胰腺14例为材料,应用免疫荧光染色和逆转录聚合酶链反应（RT—PCR）方法检测nestin和Ngn3的表达情况,免疫荧光染色检测胰腺内分泌标志胰岛素、胰高血糖素和外分泌标志CK-PAN和CK-19。结果nestin和Ngn3在12～14周人胚胎胰腺组织均广泛表达。nestin和Ng．3阳性细胞中均无胰岛素及胰高血糖素表达;在胰岛中未见到nestin与Ngn3共表达,但在导管中可见共表达。RT—PCR结果显示12～14周人胚胎胰腺中均有nestin和Ngn3的表达。结论Ngn3和nestin在人胚胎胰腺未分化细胞中表达,而具有分泌功能的内分泌细胞无表达。     

成人胰腺干细胞分离及转分化为胰岛的研究

目的 通过对成人胰腺干细胞分离和转分化为胰岛过程的研究以便更进一步了解及改进胰腺干细胞分离、培养、鉴定方法。方法 成人胰腺组织以胶原酶消化，密度梯度离心法获得纯化的胰腺外分泌细胞、导管上皮细胞和胰岛。导管上皮细胞在体外共培养27d，观察细胞形态学变化及干细胞特异性转录基因PDX—1，CK—19蛋白等的表达。结果 上述方法可获得大量胰腺导管上皮细胞。体外培养第1天即可见PDX—1，CK—19阳性细胞，胰腺导管上皮细胞迅速分裂增殖并转变为有分化能力的干细胞继而转分化为三维结构的胰岛细胞。培养27d后，平均每克胰腺组织可生成760个胰岛。结论 用改进的方法可获得大量成人胰腺导管上皮细胞，并可在体外转分化为大量具有内分泌功能的胰岛，可能为克服胰岛移植的供体短缺提供一条新途径。     

成人胰腺干细胞转分化为胰岛的研究

目的：通过对成人胰腺干细胞转分化为胰岛过程的研究以便更深入了解及改进胰腺干细胞分离、培养、鉴定方法。方法：成人胰腺组织经胶原酶消化后,用密度梯度离心法将胰腺外分泌细胞、导管上皮细胞和胰岛分离、纯化,导管上皮细胞即具有转分化潜能的干细胞,在体外先后以CMRL1066和无血清DMEM／F12培养液共培养27d,在培养的不同时间点取样本于光镜和电镜下观察细胞形态学变化及干细胞特异性转录基因PDX－1,CK－19蛋白等单抗的免疫组化染色,并测定培养液中的淀粉酶和胰岛素含量。结果：上述方法可获得大量以往在胰岛分离时丢弃的胰腺导管上皮细胞。经体外一定条件的培养后,第1天即可见PDX－1,CK－19阳性细胞,胰腺导管上皮细胞迅速分裂增殖并转变为有分化能力的干细胞继而转分化为三维结构的胰岛细胞。培养27d后,平均每克胰腺组织可生成760个胰岛。结论：成人胰腺的导管上皮具有干细胞潜能并可在体外转分化为大量具有内分泌功能的胰岛,用此方法获得大量的胰岛可能为克服胰岛移植的供体短缺提供一条新的途径。     

同种异体胰岛及胰腺干细胞来源的胰岛样结构序贯移植治疗糖尿病

目的 观察同种异体大鼠胰岛及胰腺干细胞来源的胰岛样结构序贯移植在糖尿病治疗中的作用.方法 分离胰腺组织获得胰岛及胰腺导管上皮细胞,将具有干细胞潜能的胰腺导管上皮细胞在体外培养27d.将新鲜分离的胰岛(200±50)个及诱导分化2周的胰腺干细胞来源的胰岛样结构(2×106)个序贯移植到糖尿病大鼠的肾被膜下观察大鼠的血糖及生存情况.结果 将胰岛及胰腺干细胞来源的胰岛样结构序贯移植到同一糖尿病大鼠3周后血糖仍在5 mmol/L水平,对照组血糖无明显下降.结论 胰腺干细胞可诱导分化为分泌胰岛素的胰岛样结构,胰岛及胰腺干细胞来源的胰岛样结构序贯移植对大鼠糖尿病有治疗作用.     

免疫磁性分选骨髓干细胞亚群Thy-1lowLin-Sca-1+

目的 采用免疫磁性细胞分选系统(MACS)分离纯化骨髓干细胞亚群Thy-1^low Lin^- Sca-1^ 。方法 收集小鼠股骨骨髓细胞，用MACs系统，通过三步分选步骤选择Thy-1^low Lin^- Sca-1^ 细胞。去除Lin^ 细胞，得骨髓干细胞亚群，Thy-1^low Lin^- Sca-1^ ，流式细胞仪分析其纯度，计算回收率、结果 分选出的Thy-1^low Lin^- Sca-1^ 细胞纯度和回收率分别为72．36％，82．43％，达到MACS分选CD34^ 细胞水平。结论 MACS系统能有效分选骨髓干细胞亚群Thy-1^low Lin^-Sca-1^ ，纯度和回收率高。     

乳腺导管扩张症（附96例报告）

目的 探讨乳腺导管扩张症的诊断及治疗。方法 分析1961－2000年经手术及病理证实的乳腺导管扩张症96例的临床资料。结果 术前误诊72例（75．0％）。根据临床表现的不同采用相应的手术方式：乳管切除术、肿块局部切除术、乳腺区段切除术、单纯乳房切除术、切开引流术、瘘管切除术、乳癌根治术。治愈88例（91．7％），另18例术后症状无明显减轻或复发。结论 乳腺导管扩张症易误诊，手术是治疗的主要手段。     

Functional Culture Models to Study Mechanisms Governing Apoptosis in Normal and Malignant Mammary Epithelial Cells

Mammary tissue homeostasis depends upon dynamicinteractions between the epithelial cells, theirmicroenvironment (including the basement membrane andthe stroma), and the tissue architecture, whichinfluence each other reciprocally to regulate growth,death and differentiation in the gland. To study howapoptosis is regulated in normal mammary cells, and tounderstand its role in breast tumor pathogenesis, we need model systems that recapitulate breasttissue architecture and microenvironment in culture. Wehave established culture models of primary andestablished nonmalignant mammary cell lines from both rodent and human, and defined procedures tostudy how cell and tissue architecture affect signalingby the basement membrane. We show that both a basementmembrane and an organized tissue structure are required to achieve sustained mammary cellsurvival. These models could now be used to investigatehow the basement membrane represses apoptosis in normalcells, and how breast cancers becomedeath-resistant.     

Oddi括约肌成型术后患者胆汁促增殖活性的探讨

目的　观察经十二指肠Oddi括约肌成型术 (TS)后患者胆汁 (TSB)对人胆管癌细胞QBC 93 9生长的影响 ,探讨TS与胆管癌发生与发展的关系。方法　应用四唑蓝 (MTT)比色法检测 12份TSB和10份正常胆汁 (NB)对QBC93 9细胞增殖的影响 ,应用流式细胞仪测定细胞周期和凋亡。结果　TSB与NB比较 ,前者明显促进QBC 93 9细胞增殖 (P <0 .0 5 ) ;TSB处理 2 4h的QBC93 9细胞增殖指数显著上升 (P <0 .0 5 )。结论　TSB具有潜在的促增殖活性 ,TS与胆管癌的发生与发展关系密切。     

Teriparatide (PTH 1‐34) Treatment Increases Peripheral Hematopoietic Stem Cells in Postmenopausal Women

Cells of the osteoblast lineage play an important role in regulating the hematopoietic stem cell (HSC) niche and early B‐cell development in animal models, perhaps via parathyroid hormone (PTH)‐dependent mechanisms. There are few human clinical studies investigating this phenomenon. We studied the impact of long‐term daily teriparatide (PTH 1‐34) treatment on cells of the hematopoietic lineage in postmenopausal women. Twenty‐three postmenopausal women at high risk of fracture received teriparatide 20 mcg sc daily for 24 months as part of a prospective longitudinal trial. Whole blood measurements were obtained at baseline, 3, 6, 12, and 18 months. Flow cytometry was performed to identify hematopoietic subpopulations, including HSCs (CD34+/CD45(moderate); ISHAGE protocol) and early transitional B cells (CD19+, CD27‐, IgD+, CD24[hi], CD38[hi]). Serial measurements of spine and hip bone mineral density (BMD) as well as serum P1NP, osteocalcin, and CTX were also performed. The average age of study subjects was 64 ± 5 years. We found that teriparatide treatment led to an early increase in circulating HSC number of 40% ± 14% (p = 0.004) by month 3, which persisted to month 18 before returning to near baseline by 24 months. There were no significant changes in transitional B cells or total B cells over the course of the study period. In addition, there were no differences in complete blood count profiles as quantified by standard automated flow cytometry. Interestingly, the peak increase in HSC number was inversely associated with increases in bone markers and spine BMD. Daily teriparatide treatment for osteoporosis increases circulating HSCs by 3 to 6 months in postmenopausal women. This may represent a proliferation of marrow HSCs or increased peripheral HSC mobilization. This clinical study establishes the importance of PTH in the regulation of the HSC niche within humans. © 2014 American Society for Bone and Mineral Research.     

Immunotherapeutic Approaches for the Treatment of Breast Cancer

The application of immunotherapeutic principlesto the treatment and prevention of breast cancer is arelatively new undertaking. Although cytokine infusions,cancer vaccines, and T cell therapy have been extensively studied in solid tumors such asmelanoma and renal cell carcinoma, the therapeuticefficacy of these approaches is not well explored inbreast cancer. The recent definition of tumor-specific immunity in breast cancer patients and theidentification of several breast cancer antigens hasgenerated enthusiasm for the application of immune-basedtherapies to the treatment of breast malignancies. In general, immunotherapies can be consideredeither non-specific, such as a general immunomodulator(e.g., a cytokine), or tumor-specific (e.g., a vaccinethat targets breast cancer tumor antigens). This review describes three major immunotherapeuticstrategies that have the potential to enhance orgenerate an anti-breast cancer T cell immune response:(i) cytokine therapy; (ii) cancer vaccines; and (iii) T cell therapy, and explores how each strategyhas been applied to the treatment of breastcancer.     

KIF26B Silencing Prevents Osseous Transdifferentiation of Progenitor/Stem Cells and Attenuates Ectopic Calcification in a Murine Model

Ectopic calcification is an osteogenic process that leads to the formation of inappropriate bone within intra-articular soft tissues, often in response to injury or surgery. The molecular mechanisms governing this phenotype have yet to be determined. Using a population genetics approach, we identified an association of the kinesin superfamily member 26b (Kif26b) with injury-induced ectopic calcification through quantitative trait locus analysis of recombinant inbred mouse strains, consistent with a genomewide association study that identified KIF26B as a severity locus for ectopic calcification in patients with hip osteoarthritis. Despite these associations of KIF26B with ectopic calcification, its mechanistic role and functional implications have not yet been fully elucidated. Here, we aim to decipher the functional role of KIF26B in osseous and chondrogenic transdifferentiation of human and murine progenitor/stem cells and in a murine model of non-invasive injury-induced intra-articular ectopic calcification. We found that KIF26B ablation via lentivirus-mediated shRNA significantly arrested osteogenesis of progenitor/stem cells and suppressed the expression of typical osteogenic marker genes. Conversely, KIF26B loss-of-function increased chondrogenesis as demonstrated by enhanced Safranin-O staining and by the elevated expression of chondrogenic marker genes. Furthermore, cell function analysis revealed that KIF26B knockdown significantly decreased cell viability and proliferation and induced cellular apoptosis. Mechanistically, loss of osteogenesis was reverted by the addition of a Wnt agonist, SKL2001, demonstrating a role of KIF26B in canonical Wnt/β-catenin signaling. Finally, intra-articular delivery of Kif26b shRNA in B6-129SF2/J mice significantly hampered the development of intra-articular ectopic calcification at 8 weeks after injury compared with mice treated with non-target scrambled shRNA. In summary, these observations highlight that KIF26B plays a crucial role in ectopic bone formation by repressing osteogenesis, but not chondrogenesis, potentially via modulating Wnt/β-catenin signaling. These findings establish KIF26B as a critical determinant of the osteogenic process in pathologic endochondral bone formation and an actionable target for pharmacotherapy to mitigate ectopic calcification (and heterotopic ossification). © 2021 American Society for Bone and Mineral Research (ASBMR).     

Ephrin B2/EphB4 Mediates the Actions of IGF‐I Signaling in Regulating Endochondral Bone Formation

Ephrin B2/EphB4 mediates interactions among osteoblasts (OBs), osteoclasts (OCLs), and chondrocytes to regulate their differentiation. We investigated the role of ephrin B2/EphB4 signaling in mediating the anabolic effects of insulin‐like growth factor‐I (IGF‐I) and parathyroid hormone (PTH) on those cells and overall endochondral bone formation. Immunohistochemistry demonstrated that the expression of ephrin B2 in OBs, OCLs, and osteocytes, and the expression of EphB4 in OBs and osteocytes was dramatically decreased in global IGF‐I knockout mice. Inactivation of EphB4 by EphB4 small, interfering RNA (siRNA) in cultured bone marrow stromal cells significantly decreased the mRNA levels of OB differentiation markers and abolished the stimulatory effects of IGF‐I on these markers. Blocking the interaction of EphB4 and ephrin B2 in the OB‐OCL cocultures with the EphB4 specific peptide TNYL‐RAW or deletion of ephrin B2 in OCL prior to coculture led to fewer and smaller tartrate‐resistant acid phosphatase (TRAP)‐positive cells, decreased expression of OB differentiation markers, and blunted response to IGF‐I for both OCL and OB differentiation. In the growth plate, both ephrin B2 and EphB4 are expressed in late stage proliferating and prehypertrophic chondrocytes, and their expression was decreased in mice lacking the IGF‐I receptor specifically in chondrocytes. In vitro, blocking the interaction of EphB4 and ephrin B2 in chondrogenic ATDC5 cells with TNYL‐RAW significantly decreased both basal and IGF1‐induced expression of type II and type X collagen. In the cocultures of ATDC5 cells and spleen cells (osteoclast precursors), TNYL‐RAW decreased the numbers of TRAP‐positive cells and the expression of nuclear factor of activated T cells, cytoplasmic 1 (NFATc1) and receptor activator of NF‐κB (RANK), and blocked their stimulation by IGF‐I. Our data indicate that IGF‐I/IGF‐IR signaling promotes OB, OCL, and chondrocyte differentiation via ephrin B2/EphB4 mediated cell‐cell communication. © 2014 American Society for Bone and Mineral Research.     

Mammary Involution in Dairy Animals

Lifetime milk production is maximized when dairycows are pregnant during approximately 70% of eachlactation. Between lactations, a nonlactating period isnecessary for optimal milk production in the succeeding lactation. With cessation of milking, alveolarstructure is largely maintained and little or no loss ofcells occurs. However, increased apoptosis and cellproliferation, relative to that in lactating glands during the same stage of gestation, suggestthat a nonlactating period serves to promote cellturnover prior to the next lactation. Even in theabsence of pregnancy, mammary involution in dairyanimals occurs at a slower rate than in rodents;alveolar structure is maintained for several weeks andlactation can be reinitiated after four weeks or more ofinvolution. Although apoptosis appears to be initiated within a similar time frame to that in rodents,the maximum proportion of apoptotic epithelial cellsappears to be lower than in rodents, and apoptosis maybe accompanied by an initial increase in cell proliferation. The ability to manipulateapoptosis and cell proliferation during the nonlactatingperiod and during lactation is expected to provideenormous benefits to the dairy industry.