诱导小鼠破骨前体细胞成熟分化的实验条件探讨

目的探讨小鼠单核细胞RAW264.7能否在RANKL诱导下向破骨细胞成熟分化。方法 RANKL作用RAW264.7细胞7天～9天,光镜、透射电镜、扫描电镜(scanning electron microscope,SEM)分别观察其细胞形态学变化,用抗酒石酸酸性磷酸酶(tartrate-resistant acid phosphatase,TRAP)染色法观察TRAP阳性的多核细胞,RT-PCR检测破骨细胞表型和功能基因表达变化情况,扫描电镜观察破骨细胞在骨片上形成骨吸收陷窝。结果光镜、透射电镜下可见细胞胞体增大,为椭圆形或不规则形,胞核5～10个,扫描电镜下可见细胞表面大量的伪足样突起;此外,RANKL能诱导RAW264.7细胞分化为TRAP染色阳性的多核破骨细胞,细胞多为超过5个核的多核巨细胞;RAW264.7细胞成熟分化后具有骨吸收功能,并且能上调Cathepsin-K、TRAP、RANK等典型破骨细胞表型和功能基因mRNA的表达。结论 RAW264.7细胞是一种较好的破骨前体细胞模型,单用50ng/ml的RANKL体外连续诱导7天以上,能明显促进它向成熟的破骨细胞分化。     

复合振动抑制RAW264.7细胞分化成熟

目的研究复合振动对核因子-κB受体活化因子配体(RANKL)诱导的RAW264.7细胞分化的影响,探讨复合振动对破骨细胞分化的影响及机制。方法 RAW264.7细胞RANKL诱导培养3或4d并施加复合振动干预,通过抗酒石酸酸性磷酸酶(TRAP)染色观察TRAP阳性多核细胞形成的变化,real-time RT-PCR分析破骨细胞特异性基因组织蛋白酶K(cathepsin K),金属蛋白酶-9(MMP-9)和TRAP表达的变化。结果复合振动能抑制RANKL诱导破骨细胞形成,下调破骨细胞特异基因cathepsin K,MMP-9和TRAP的表达。结论 RANKL促进RAW264.7细胞向破骨细胞分化,并增加特异基因的表达,但RANKL的促进作用受复合振动抑制。这进一步的阐释复合振动抗骨质疏松的作用机制。     

白细胞介素-21对RAW264.7细胞向破骨细胞分化的影响

目的 了解白细胞介素-21 (IL-21)诱导小鼠巨噬细胞系RAW264.7细胞向破骨细胞分化的作用,并探讨其可能的机制。方法1、以不同浓度IL-21(0,1,10,20,40 ng/ml)处理RAW264. 7细胞,培养5天后进行抗酒石酸酸性磷酸酶(TRAP)染色,Western Blot和免疫组化法检测降钙素受体（CTR)表达,采用Real time PCR法检测CTR和组织蛋白酶（Cathepsin)-K的 mRNA表达水平。2、以信号通路抑制剂AG490、LY294002和PD98059作用30min后再加人IL-21,培养5天后观察破骨细胞形成情况,以Western Blot检测IL-21作用不同时间点时信号通路分子总蛋白和磷酸化蛋白水平,探讨IL-21直接诱导破骨细胞分化的作用机制。结果1、在无RANKL作用的情况下,随着IL-21浓度增加TRAP阳性细胞数逐渐增多,20 ng/ml作用最强,40ng/ml时减弱。IL-21能够诱导破骨标志分子CTR和Cathepsin-K mRNA水平表达上调。Western Blot和免疫细胞化学证实,与阴性组比较,IL-21能促进CTR蛋白水平表达增高。2、PI3K-AKT通路抑制剂（LY294002)可以显著抑制IL-21诱导的 RAW264. 7细胞向破骨细胞分化,IL-21刺激5 ~ 15 min时p-AKT表达增强。结论 IL-21可不依赖RANKL直接诱导小鼠巨噬细胞系RAW264. 7细胞向破骨细胞分化,该作用可能由PI3K-AKT通路介导。     

骨保护素体外抑制小鼠单核巨噬细胞 成熟分化的实验研究

目的研究骨保护素（Osteoprotegerin, 0PG)抑制核因子NF-KB受体活化因子配体（Receptor activator of nuclear kappa B ligand,RANKL)诱导小鼠单核细胞RAW264. 7成熟分化而导致的溶骨效 应。方法50 ng/mL RANKL诱导RAW264. 7细胞1 d后,加人100 ng/mL 0PG(实验组,即0PG + RANKL组）或不加人0PG(对照组,即RANKL组）分别培养7 d和9 d,经细胞形态学观察其变化,抗 酒石酸酸性碟酸酶（Tartrate resistant acid phosphatase, TRAP)染色法观察TRAP阳性多核细胞,扫描 电镜下观察在骨片上的破骨细胞所致的骨吸收陷窝形成情况。结果对照组培养7 d时,在倒置相 差显微镜、透射电镜、光镜下可见细胞形状为椭圆形或不规则形,胞体明显较KAW264.7细胞增大, 胞核多为6 ~ 10个,扫描电镜下还可见大量伪足形成,而实验组培养7 d后,细胞形状多为圆形,且扫 描电镜下未见明显伪足形成;对照组9 d时可见大量TRAP染色阳性的多核巨细胞（含3个或3个以 上的细胞核）,而实验组中TRAP染色阳性的多核破骨细胞偶见多核巨细胞,培养9 d时很难找到多 核巨细胞;仅用RANKL诱导RAW264.7细胞分化7 d时,对照组中破骨细胞表面可见大量伪足伸出, 并形成明显的骨吸收陷窝,实验组中破骨细胞见少许伪足突出,不能看到明显的骨陷窝形成。结论 单用50 ng/mL RANKL体外连续诱导RAWM4.7细胞7 d时,可以促进成熟的破骨细胞显著分化。 100 ng/mL 0PG培养9 d能有效地抑制破骨细胞的分化,减少破骨细胞的骨吸收效应。     

RANKL诱导小鼠单核细胞RAW264.7分化成成熟破骨细胞

目的观察小鼠的单核／巨噬细胞RAW264．7的一般生物学特征及在RANKL诱导下形成成熟破骨细胞的特征。方法RANKI，诱导RAW264．7细胞6d后，用抗酒石酸酸性磷酸酶(TRAP)染色法观察TRAP阳性多核细胞，吖啶橙染色激光共聚焦显微镜(LCSM)观察多核细胞形态；诱导RAW264．7细胞9d后，RT、PCR检测RAW264．7细胞的破骨细胞表型和功能基因表达及其RANKL诱导后变化；诱导RAW264．7细胞12d后，钙磷覆盖的破骨细胞活性分析板观察破骨细胞的骨吸收功能。结果RAW264．7细胞TRAP染色阴性，单核或2个核，能表达破骨细胞表型和功能基因，无骨吸收功能。RANKL可诱导RAW264．7细胞形成TRAP阳性成熟的多核破骨细胞，上调CathepsinK、CAⅡ、integrinβ3等基因mRNA的表达。结论RAW264．7具有破骨细胞特征性基因表达谱，是一种较好的破骨前体细胞模型。RANKL可诱导RAW264．7细胞形成成熟破骨细胞。     

唑来膦酸抑制RAW264.7细胞系分化的最佳浓度体外实验

目的观察唑来膦酸盐对RAW264.7细胞系毒性作用的浓度范围和抑制RAW264.7分化为破骨细胞的最佳实验浓度。 方法以小鼠前破骨细胞系RAW264.7为研究对象,应用MTT法检测唑来膦酸盐对小鼠前破骨细胞系RAW264.7的毒性作用范围。使用TARP染色法观察不同浓度的唑来膦酸盐作用下破骨细胞的生成数目。 结果体外培养24 h后,酶联免疫反应吸光度结果显示,10^-3 mol/L（0.511±0.920）,10^-4 mol/L（0.615±0.577）唑来膦酸对小鼠前破骨细胞系RAW264.7增殖有毒性作用,与空白对照组（0.789±0.061）相比,差异有统计学意义（F=5.880,P<0.01）。TRAP染色破骨细胞计数结果显示：10^-5 mol/L（8.333±0.817）、10^-6 mol/L（10.400±1.817）、10^-7 mol/L（11.250±2.750）及10^-8 mol/L（11.143±1.864）唑来膦酸盐实验组破骨细胞数与空白对照组破骨细胞数（13.833±2.483）相比,差异具有统计学意义（F=27.972,P<0.05）,且呈浓度依赖性,当唑来膦酸盐浓度为10^-5 mol/L时,抑制效果最明显（P<0.01）。 结论唑来膦酸盐抑制RAW264.7细胞系分化为破骨细胞的最佳体外实验浓度为10^-5 mol/L。     

小鼠单核巨噬细胞白血病细胞（RAW264.7）的培养及其在诱导破骨细胞中的应用

小鼠单核巨噬细胞白血病细胞(RAW264.7)是通过Abelson鼠白血病病毒诱导BALB/c小鼠产生肿瘤后得到的细胞株。RAW264.7细胞在医学研究中应用十分普遍:它是许多白血病相关研究模型的常用细胞株;在微生物学、免疫学等研究中也十分常用;同时也是小鼠源性破骨前体细胞,可通过特定细胞因子的诱导在体外获得成熟破骨细胞,因此也成为许多骨骼疾病研究的体外模型。但RAW264.7细胞形态和分化状态多变,在实际培养中较难把握,给科研工作带来了一定困难。科研工作者在RAW264.7细胞的培养方法、细胞的形态及分化状态等方面始终观点不一,对于用RAW264.7细胞在体外诱导获得破骨细胞的方法也有许多差别。本文结合文献资料及实践,探索了RAW264.7细胞的培养条件,冻存、复苏、传代方法,以及用核因子κB受体活化因子配基(receptor activator for nuclear factor-κB ligand,RANKL)诱导其成为成熟破骨细胞的技术关键;旨在总结RAW264.7细胞的培养及诱导其分化为破骨细胞的经验教训,探讨RAW264.7细胞的培养和在体外用RANKL诱导RAW264.7细胞分化为破骨细胞的方法、技巧,供广大科研工作者借鉴。     

人成骨样细胞和前破骨样细胞ER亚型、OPG/RANKL/RANK系统、IL-6及其受体以及破骨细胞标志基因表达的研究

目的分析比较两种人成骨样细胞系(U2-OS、MG-63)和两种人前破骨样细胞系(U937、HL-60)ER亚型、OPG/RANKL/RANK系统、IL-6及其受体以及破骨细胞标志基因表达的差异,为今后研究雌激素与IL-6等细胞因子在骨组织中相互关系提供适宜的细胞模型。方法RT-PCR和免疫印迹法检测ERα、ERβ的表达,ELISA法测定IL-6的分泌,OPG、RANKL、RANK及IL-6受体的表达采用免疫印迹法进行检测,TRAP、MMP-9则采用RT-PCR技术进行分析。结果(1)转录水平及蛋白水平证实四种细胞均表达ERα和ERβ;(2)四种细胞不同程度地表达OPG和RANKL,而RANK则仅见于U937细胞表达;(3)四种细胞均表达IL-6受体(IL-6Rα、gp130),除U2-OS细胞外其余三种细胞均组成型分泌IL-6;(4)破骨细胞标志基因TRAP在两种人前破骨样细胞U937、HL-60中均表达,且表达水平相近;而MMP-9仅在U937细胞中弱表达;两种人成骨样细胞U2-OS、MG-63未见有这两种基因表达。结论筛选出用于研究雌激素与IL-6等细胞因子在骨组织中相互关系的细胞模型,同时也为今后深入阐明骨靶向和其他新型抗骨质疏松雌激素的分子机制研究奠定基础。     

M-CSF和RANKL体外诱导培养小鼠破骨样细胞及其骨吸收功能的动态观察

目的以巨噬细胞集落刺激因子(Macrophage colony-stimulating factor,M-CSF)和核因子κB受体激动剂配体(Ligand of receptor activator of NF-κB,RANKL)联合体外诱导小鼠骨髓干细胞分化为破骨样细胞,并对其骨吸收功能进行动态观察。方法分离小鼠四肢骨获取骨髓干细胞,以M-CSF和RANKL诱导培养,将盖玻片及骨磨片置入培养基内,在诱导培养的第3,6,9天分别对盖玻片行抗酒石酸酸性磷酸酶(The tartrate-resistant acid phosphatase TRAP)染色,观察细胞形态和染色情况,并计算破骨样细胞数量;同时对骨磨片进行骨吸收陷窝的观察。结果诱导培养3 d后出现含TRAP(+)颗粒的细胞,可见淡染单核和双核;诱导培养6 d后可见TRAP(+)细胞较诱导培养3 d时增多,仍以双核为主;诱导培养9 d后出现多核巨型TRAP(+)细胞,细胞核达到3个以上。并且随着诱导培养的时间延长,破骨样细胞数量逐渐增长。诱导培养第3,6天骨磨片上均未发现骨吸收陷窝,第九天出现不同形态的呈蓝紫色的吸收陷窝。结论 M-CSF和RANKL联合体外诱导小鼠骨髓干细胞形成破骨样细胞是一种有效的诱导培养方法,本实验在诱导培养第九天发现破骨样细胞具有骨吸收功能。     

铁调素对小鼠单核细胞RAW264.7膜铁转运蛋白1（FPN1）表达的影响

目的：观察铁调素对小鼠单核细胞RAW264．7膜铁转运蛋白1（ FPN1）的表达,探讨铁调素对RAW264．7细胞作用的可能通路和机制。方法将不同浓度的铁调素加入含有核因子κB受体活化因子配体（ RANKL）的RAW264．7细胞培养基,24 h后用免疫荧光和Western－blot方法测定FPN1的表达,共聚焦显微镜（ CLSM ）测定细胞内铁离子的浓度。结果 RAW264．7细胞膜上存在FPN1受体的阳性表达;在本实验铁调素浓度干预范围内,FPN1的表达随着铁调素浓度的增加呈浓度依赖性降低（P＜0．05）,同时细胞内铁离子的含量随着铁调素浓度的增加呈浓度依赖性增加（P＜0．05）。结论小鼠单核细胞RAW264．7是铁调素作用的靶细胞,铁调素可通过降解其细胞膜上的FPN1增加细胞内的铁离子。     

不同浓度白藜芦醇对破骨细胞分化的影响及自噬的作用

目的研究不同浓度白藜芦醇(RSV)对破骨细胞分化的影响及自噬在其中的作用。方法RANKL诱导RAW264.7细胞分化过程中,加入不同浓度(0、0.1、0.5、1、5及10μmol/L)RSV,CCK-8检测干预后12、24、48、72 h时的细胞活力;TRAP染色观察破骨细胞分化程度。加或不加入3-甲基嘌呤(3-MA)抑制自噬,RT-PCR检测破骨分化相关标志物TRAP、MMP-9、CTSK和自噬相关标志物LC3、Beclin-1、P62的mRNA表达情况;Western blot检测自噬相关蛋白LC3II/I、Beclin-1、P62的表达情况。结果RANKL诱导分化过程中,细胞增殖活力提高,加入0.1~10μmol/L的RSV,细胞活力先上升后下降,在0.5μmol/L时达到最大;0.1μmol/L和0.5μmol/L的RSV能提高TRAP染色阳性的破骨细胞数和TRAP、MMP-9、CTSK、LC3、Beclin-1、P62的mRNA表达,自噬相关蛋白LC3II/I和Beclin-1也增加,P62的蛋白表达则减少;而1~10μmol/L RSV随浓度升高相关mRNA及蛋白LC3II/I和Beclin-1的表达减少,P62的蛋白表达增加;加入3-MA后,相关mRNA及蛋白LC3II/I和Beclin-1的表达减少,P62的蛋白表达增加。结论RSV浓度在0.1~10μmol/L范围内,破骨细胞分化和自噬水平先升高后降低,抑制自噬可以抑制破骨细胞的分化。白藜芦醇影响破骨细胞分化可能部分是通过调节自噬发挥作用。     

The generation of osteoclasts from RAW 264.7 precursors in defined,serum-free conditions

Osteoclasts are the unique cell type capable of resorbing bone. The discovery of the TNF-ligand family member, RANKL, has allowed more reliable study of these important cells. The mouse monocytic cell line, RAW 264.7, has been shown to readily differentiate into osteoclasts upon exposure to recombinant RANKL. Unlike primary osteoclast precursors, there is no requirement for the addition of macrophage colony stimulating factor (M-CSF). However, to date, their differentiation has always been studied in the context of added foetal calf serum (FCS). FCS is a complex and largely undefined mixture of growth factors and matrix proteins, and varies between batches. For this reason, osteoclastogenesis would ideally be studied in the context of a defined, serum-free medium. RAW 264.7 cells were cultured in serum-replete α-MEM or serum-deprived medium (SDM) shown previously to support the growth of human osteoclasts in a co-culture with normal osteoblasts. In SDM, in the presence of recombinant RANKL, RAW 264.7 cells readily differentiated into tartrate resistant acid phosphatase (TRAP) positive multinucleated osteoclast-like cells, a process that was enhanced with the addition of 1α,25-dihydroxyvitamin D₃ (1,25D). While the osteoclasts grown in SDM were smaller in size compared with those derived in serum-replete media, their resorptive capacity was significantly increased as indicated by a twofold increase in average resorption pit size. In conclusion, we describe a defined model for studying osteoclast differentiation and activity in the absence of serum, which will be ideal for studying the role of agonistic and antagonistic molecules in this process.     

Effect of interleukin 6 on basal and FSH-stimulated secretion of estradiol and progesterone by human granulosa cells in vitro

Aim: To determine the effects of interleukin-6 (IL-6) on the secretion ofestradiol and progesterone by human granulosa cells in vitro. Methods:Granulosa cells were obtained from infertile patients undergoing IVF ETtreatment and cultured with serum-free supplemented HAM's F10 medium.In the absence or presence of FSH, granulosa cells were treated with differ-ent concentrations of gene recombinant human iterlukin-6 (rhIL-6). Themedia were collected after 24, 48, 72 and 96 h and assayed for estradiol andprogesterone. IL-6 and R mRNA was determined by means of RNA slotblot. Results: IL-6 had a significant inhibitory effect on estradiol secre-tion, especially in the presence of FSH. IL-6 inhibited the FSH-stimulatedprogesterone secretion, but not the basal progesterone release. The inhibi-tion shows certain degrees of dose- and time-dependency. Conclusion:IL-6 participates in the regulation of ovarian function through its inhibitoryeffect on FSH-stimulated steroidogenesis by granulosa cells.     

Production of IL-7 is increased in ovariectomized mice,but not RANKL mRNA expression by osteoblasts/stromal cells in bone,and IL-7 enhances generation of osteoclast precursors in vitro

Osteoclastogenic cytokines produced by T and B lineage cells and interleukin (IL)-7-induced expansion of the pool size of osteoclast precursors have been suggested to play an important role in acceleration of osteoclastogenesis induced by estrogen deficiency. However, the contribution of increased RANKL produced by osteoblasts/stromal cells to increase osteoclastogenesis in a mouse model of estrogen-deficient osteoporosis and in vitro effects of IL-7 on osteoclast precursor generation remain controversial. Thus, we investigated the effect of ovariectomy (OVX) of mice on production of RANKL, osteoprotegerin (OPG), and IL-7 in bone and the effect of IL-7 on osteoclast precursor generation in vitro. OVX did not significantly stimulate mRNA expressions of RANKL and OPG in whole femurs. Because the epiphysis, but not the femoral shaft (diaphysis) or bone marrow, is the main site of osteoclastogenesis, it is important to specifically analyze mRNA expression by osteoblasts/stromal cells at these parts of the femur. Therefore, we isolated RNA from bone marrow cell-free epiphysis, diaphysis, and flushed-out bone marrow and examined mRNA expression. The results showed no significant changes of RANKL and OPG mRNA expression in any part of the femur. In addition, OVX did not significantly affect RANKL and OPG mRNA expression by the adherent stromal cells isolated from flushed-out bone marrow cells but did stimulate RANKL mRNA expression by B220⁺ cells in the nonadherent cell fraction. On the other hand, OVX increased IL-7 mRNA expression in the femur as well as IL-7 concentrations in bone fluid. In cultures of unfractionated bone cells isolated by vigorous agitation of minced whole long bones to release the cells tightly attached to the bone surfaces, but not in cocultures of clonal osteoblasts/stromal cells and flushed-out bone marrow cells, IL-7 stimulated generations of osteoclasts as well as osteoclast precursors. These data suggest that increased RANKL production by osteoblasts/stromal cells is unlikely to play a central role in acceleration of osteoclastogenesis in estrogen deficiency of mice and that IL-7 stimulates osteoclast precursor generation, presumably through an action of IL-7 on the cells attached to bone rather than on cells contained in the bone marrow cell population.