小鼠骨髓造血基质细胞体外培养及其功能的研究

采用细胞培养从正常LACA雄性小鼠骨髓中分离得到1株造血基质细胞（HSC），该细胞胞体较大，呈多角形，不吞噬酵母多糖，HSC粘壁层有其培养上清液均具有明显刺激CFU－GM体外增殖分化的功能，将HSC输注到经射线照射的雌性小鼠体内，PCR技术检测结果显示，HSC具有重建受体小鼠造血微环境的作用。     

胎肝Sca-1+细胞移植造血重建

目的:观察胚胎肝Sca-1+细胞能否重建造血。方法:免疫磁珠法分离孕14 5dC57BL/6J小鼠的雄性胚胎肝的Sac-1+细胞,经尾静脉注射(细胞数为2 0×103/只)移植到致死剂量(10 0Gy)放射线照射的8～10周C57BL/6J雌性小鼠;sry基因PCR方法检测受体小鼠外周血中供体来源的血细胞。结果:移植胚胎肝Sca-1+细胞的实验组小鼠外周血各种血细胞数在5d后开始下降,在10d后开始上升,20d恢复至正常,均存活6个月以上;而未移植Sca-1+造血干细胞的对照组小鼠20d内全部死亡。多聚酶链式反应(PCR)显示实验组小鼠外周血细胞sry基因检测阳性,未移植对照组小鼠外周血细胞sry基因检测均为阴性;随着移植时间的延长,移植小鼠外周血细胞sry基因的PCR扩增物量增加,说明雄性胚胎供体来源的细胞在增加,反映造血重建情况。结论:胚胎肝Sca-1+细胞能重建致死剂量放射线照射的小鼠造血功能。     

小鼠非清髓性单倍体相合骨髓移植模型的建立

目的建立小鼠非清髓性单倍体相合骨髓移植模型,为研究移植前诱导免疫耐受或移植后输注供者细胞促进植入提供研究平台。方法以CB6F1雌性小鼠为受鼠,移植前1 d予450 cGy全身照射（TBI）后,随机分为2组,实验组移植0 d输注C57BL/6雄性小鼠骨髓有核细胞5×107/只,对照组不予移植。然后监测受鼠造血恢复、检测供鼠性别决定基因（SRY）判断植入情况,以及外周血供者细胞尤其CD3＋细胞嵌合状态,同时观察小鼠急性移植物抗宿主病（aGVHD）的发生情况。结果对照组小鼠均存活,仅表现轻度aGVHD,血象移植后30 d内基本恢复正常水平。实验组小鼠SRY基因在移植后＋14 d、＋30 d、＋60 d时检测PCR结果均阳性,供鼠外周血淋巴细胞、单核细胞、粒细胞嵌合率在移植后14 d分别为23.8%、36.9%%、19.4%;30 d分别为49.9%、53.2%、54.4%;60 d分别为67.6%、51.6%、56.9%,其中CD3＋细胞嵌合率分别为4.4%、21.2%、54.4%。结论 450 cGyTBI的非清髓性预处理方案,可以诱导受鼠免疫耐受、供者骨髓细胞植入,嵌合率处于中低水平混合嵌合状态。     

胎肝Sca-1+细胞治疗STZ诱导小鼠糖尿病的实验研究

目的探讨小鼠胎肝组织中的干细胞抗原1阳性的细胞(Sca-1+细胞)治疗链脲佐菌素(STZ)诱导糖尿病鼠的潜能.方法取14.5 d的C57BL/6J小鼠胎肝,制作细胞悬液,用单克隆免疫磁珠细胞分离技术分离Sca-1+细胞,将2×105个雄性小鼠Sca-1+细胞输注到STZ诱导的C57BL/6J雌性小鼠体内,以后每7 d定时测定小鼠血糖,第38 d处死受体小鼠取胰腺组织固定、切片,免疫组化观察胰腺组织中胰岛素阳性的β细胞变化.结果小鼠胎肝Sca 1+细胞能够有效抑制STZ诱导小鼠血糖的持续升高,明显降低糖尿病鼠的死亡率.受体小鼠胰岛细胞结构清楚,其中可见表达胰岛素的β细胞,荧光原位杂交显示小鼠胰岛内有Y染色体阳性杂交点.结论小鼠胎肝Sca-1+细胞具有一定的治疗小鼠糖尿病的作用.     

失血性贫血小鼠恢复过程中骨髓基质金属蛋白酶变化

目的:观察失血性贫血小鼠恢复过程中骨髓基质金属蛋白酶-2和-9(MMP-2,MMP-9)的变化,并探讨其在造血调控中的作用.方法:采用全自动血细胞分析仪、免疫组化和酶谱电泳法分别检测失血性贫血小鼠恢复过程中外周血RBC和Hb数量、骨髓细胞MMP-2和MMP-9表达以及骨髓造血微环境MMP-2和MMP-9的活性变化.结果:(1)与正常对照组相比外周血RBC和Hb数量失血后第1d急剧下降.随着恢复时间的延长,二者数目逐渐上升,到第9d已接近正常对照组水平.(2)在正常对照组检测到了较弱的MMP-2和MMP-9的表达.与正常对照组相比,失血后1d组、3d、5d和7d组小鼠骨髓细胞中MMP-2和MMP-9表达明显增加,MMP-2和MMP-9表达分别于失血后5d和3d达到峰值.与1d组相比,3d组小鼠骨髓细胞中MMP-2和MMP-9表达以及5d组小鼠骨髓细胞中MMP-2表达明显增加.(3)正常对照组中检测到proMMP-2,proMMP-9和MMP-9 3条酶带,MMP-9的活性最强.失血后1d,proMMP-2,proMMP-9和MMP-9的活性均急剧升高.随着恢复时间的延长,3者的活性逐渐降低,到第9d时恢复到接近正常对照组水平.结论:失血性贫血小鼠可能通过骨髓细胞中MMPs表达增加以及骨髓造血微环境中MMPs活性升高来促进骨髓造血功能增强,使外周血RBC和Hb的数量恢复到正常水平.     

胎牛成纤维细胞的分离培养

应用组织块培养法从胎牛耳部分离培养了胎牛成纤维细胞。应用PCR方法鉴别了细胞的性别。选择雌性成纤维细胞,进行了形态观察、生长曲线测定、染色体分析。结果表明,分离培养的细胞具有正常的大小、形态、分裂增殖特性和染色体数目。胎牛成纤维细胞的培养方法的建立以及其相关的生物学特性的分析,有利于给同种和异种体细胞克隆牛研究提供形态良好、染色体数目正常的供体细胞,同时也为体细胞转基因等其他领域的研究提供了基础条件。     

人脐带间充质干细胞对小鼠衰老进程中骨髓细胞集落生成的影响

目的:探讨人脐带间充质干细胞(hUC-MSC)对小鼠衰老进程中骨髓造血干祖细胞增殖能力的影响.方法:由足月新生儿脐带分离间充质细胞(MSC)作供体,6月龄Balb/c小鼠为受体,将小鼠随机分为实验组和对照组,实验组输注MSC(5×10~5/只),每月1次,共4次;对照组输注生理盐水.干预开始后第3个月和第6个月分别比较两组的单侧股骨骨髓有核细胞计数(BMNC)、造血祖细胞集落培养(CFU-GM、CFU-E、CFU-MK)和外源性脾集落形成单位计数(CFU-S).结果:干预后第3个月时,实验组BMNC、CFU-GM和CFU-MK高于对照组,而CFU-E和CFU-S无明显差别;干预后第6个月时,实验组的上述指标均明显高于对照组,且随着衰老出现下降的速度明显慢于对照组,差异有显著性(P<0.05).结论:定期输注hUC-MSC可以相对增加宿主自身造血干祖细胞的生物学活性,从而延缓小鼠造血组织的自然衰老进程.     

The mechanism of adipocyte differentiation and regulation of hematopoietic microenvironment

在人体生长发育与衰老过程中骨髓会逐渐由红骨髓转变成为黄骨髓,即骨髓脂肪化,其本质是骨髓中脂肪细胞增多.骨髓脂肪细胞对造血微环境具有负性调节作用,能抑制骨髓造血、抑制造血重建时造血干细胞在骨髓中的植入.深入研究骨髓脂肪化机制对促进某些疾病过程中造血恢复、提高造血干细胞移植效率具有一定意义.脂肪细胞的形成主要包括间充质干细胞向前体脂肪细胞的定向分化及其终末分化两个阶段.本文主要阐述细胞形态变化和细胞外基质通过WNT和RHO-family GTPase信号级联通路调节前体脂肪细胞的定向分化,成脂刺激因素通过PPARγ的表观遗传学途径诱导前体脂肪细胞的终末分化,以及PPARγ和C/EBP的相互作用维持脂肪细胞的基因表达.     

抗小鼠雄性特异性抗原（H—Y抗原）单克隆抗体的研究

将经Ｃ５７ＢＬ／６Ｊ雄鼠脾细胞免疫的同系雌鼠脾细胞与Ｂａｌｂ／ｃ小鼠骨髓瘤ＳＰ２／０细胞进行融合,以雌、雄鼠脾细胞作细胞性ＥＬＩＳＡ、间接免疫荧光和精细胞间接免疫荧光技术进行筛选,共建立了５株稳定分泌抗Ｈ－Ｙ抗原的单克隆抗体杂交瘤细胞株。该杂交瘤细胞可在Ｃ５７ＢＬ／６Ｊ与Ｂａｌｂ／ｃ杂交子一代雌性小鼠腹腔生长并形成腹水性抗体。鉴定结果证明这些抗体具有较好的特异性。     

复硝酚钠的致突变性研究

检测复硝酚钠有无致突变作用,为其安全生产和使用提供依据.采用鼠伤寒沙门氏菌回复突变试验(Ames试验),用TA97,TA98,TA100,TA102菌株,加与不加S9,剂量设为:0,250,500,1 000,2 000 μg/皿;小鼠骨髓多染红细胞微核试验,剂量设为雄、雌性小鼠给药剂量均为:15.8,31.6,63.2 mg/kg;小鼠睾丸精母细胞染色体畸变试验,剂量设为:15.8,31.6,63.2 mg/kg检测有无致突变作用.结果为Ames试验中各测试浓度的诱发回变菌落数均未超过自发回变菌落数的2倍;小鼠骨髓多染红细胞微核试验和小鼠睾丸精母细胞染色体畸变试验,各剂量组和溶剂对照组的微核率进行统计学处理,未见有显着性差异(P＞0.05),表明各项试验结果均为阴性.因此在本试验条件下,复硝酚钠无致突变作用.     

Cell fusion is the principal source of bone-marrow-derived hepatocytes

Evidence suggests that haematopoietic stem cells might have unexpected developmental plasticity, highlighting therapeutic potential. For example, bone-marrow-derived hepatocytes can repopulate the liver of mice with fumarylacetoacetate hydrolase deficiency and correct their liver disease. To determine the underlying mechanism in this murine model, we performed serial transplantation of bone-marrow-derived hepatocytes. Here we show by Southern blot analysis that the repopulating hepatocytes in the liver were heterozygous for alleles unique to the donor marrow, in contrast to the original homozygous donor cells. Furthermore, cytogenetic analysis of hepatocytes transplanted from female donor mice into male recipients demonstrated 80,XXXY (diploid to diploid fusion) and 120,XXXXYY (diploid to tetraploid fusion) karyotypes, indicative of fusion between donor and host cells. We conclude that hepatocytes derived form bone marrow arise from cell fusion and not by differentiation of haematopoietic stem cells.     

Ex vivo expansions and transplantations of mouse bone marrow－derived hematopoietic stem／progenitor cells

To examine the effects of co-culture with bone marrow mesenchymal stem cells on expansion of hematopoietic tem/progenitor cells and the capacities of rapid neutrophil engraftment and hematopoietic reconstitution of the expanded ells, we expanded mononuclear cells (MNCs) and CD34^ /c-kit^ cells from mouse bone marrow and transplanted the expanded cells into the irradiated mice. MNCs were isolated from mouse bone marrow and CD34^ /c-kit^ cells were selected from MNCs by using MoFlo Cell Sorter. MNCs and CD34^ /c-kit^ cells were co-cultured with mouse bone marrow-derived mesenchymal stem cells (MSCs) under a two-step expansion. The expanded cells were then transplanted into sublethally irradiated BDF 1 mice. Results showed that the co-culture with MSCs resulted in expansions of median total nucleated cells, CD34^ cells, GM-CFC and HPP-CFC respectively by 10.8-, 4.8-, 65.9- and 38.8-fold for the mononuclear cell culture, and respectively by 76.1-, 2.9-, 71.7- and 51.8-fold for the CD34^ /c-kit^ cell culture. The expanded cells could rapidly engraft in the sublethally irradiated mice and reconstitute their hematopoiesis. Co-cultures with MSCs in conjunction with two-step expansion increased expansions of total nucleated cells, GM-CFC and HPP-CFC, which led us to conclude MSCs may create favorable environment for expansions of hematopoietic stem/progenitor cells. The availability of increased numbers of expanded ceils by the co-culture with MSCs may result in more rapid engraftment ofneutrophils following infusion to transplant recipients.     

小鼠腹腔注射阿霉素诱导骨髓细胞微核率的最佳时间—剂量效应分析

目的：寻找一次染毒条件下,腹腔注射阿霉素诱导小鼠骨髓细胞微核率出现峰值的时间-剂量条件。方法：将150只小鼠随机分为5组,每组30只,雌雄各半。腹腔注射,1次给药,对照组给生理盐水,处理组的阿霉素剂量分别是2.5 mg/kg、5 mg/kg、10 mg/kg和20 mg/kg。染毒18 h、24 h、30 h、48 h和72 h后取小鼠骨髓进行微核分析,评价阿霉素对小鼠的遗传毒性作用。结果：理想的腹腔注射诱导的小鼠骨髓细胞微核率峰值的条件就是：一次染毒,阿霉素剂量在10%LD50即2.5 mg/kg至80%LD50即20 mg/kg的范围内剂量越大微核率越高,取样时间在30~48 h间微核率最高。     

Clonal nature of mast-cell clusters formed in W/Wv mice after bone marrow transplantation.

We have recently found that the number of mast cells in the skin of adult W/Wv mice is less than 1% of that observed in congeneic +/+ mice, and that no mast cells are detected in other tissues of W/Wv mice. After the transplantation of bone marrow cells from congeneic +/+ mice, the number of mast cells in the skin, stomach, caecum and mesentery of the W/Wv mice increased to levels similar to those of the +/+ mice. Study of the mast-cell number in the W/Wv mice at various times after transplantation suggested to use that mast cells might develop in groups, particularly in the skin and mesentery. In this report, we have attempted to elucidate the possible clonal origin of such mast-cell clusters from a single precursor cell, using giant granules of beige (C57BL/6-bgJ/bgJ, Chediak-Higashi syndrome) mice as a marker to identify the origin of the mast cells (Fig. 1). We found that when WB-W/+xC57BL/6-Wv (WBB6F1)-W/Wv mice were injected with a mixture of bone marrow cells from beige C57BL/6 mice and normal C57BL/6 mice, more than 95% of mast-cell clusters consisted of either beige-type cells alone or normal-type cells alone. We conclude, therefore, that the cluster of mast cells originated from a single precursor cell.     

Germ cell transplantation in infertility mouse

This work investigated the spermatogenesis in an infertility BALB/c-nu mouse model by reinfusing germline stem cells into seminiferous tubules. Donor germ cells were isolated from male FVB/NJ-GFP trensgenic mice. Seminiferous tubule microinjection was applied to achieve intratubular germ cell transfer. The germ cells were injected into exposed testes of the infertility mice. We used green fluorescence and DNA analysis of donor cells from GFP transgenic mice as genetic marker. The natural mating and Southern blot methods were applied to analyze the effect of sperm cell transplantation and the sperm function after seminiferous tubule microinjection. The spermatogenesis was morphologically observed from the seminiferous tubules in 41/60 （68.33%） of the injected recipient mice using allogeneic donor cells. In the colonized testes, matured spermatozoa were seen in the lumen of the seminiferous tubules. In this research, BALB/c-nu infertility mouse model, the recipient animal, was used to avoid immunological rejection of donor cells, and germ cell transplantation was applied to overcome infertility caused by busulfan treatment. These results demonstrate that this technique of germ cell transplantation is of great use. Germ cell transplantation could be potentially valuable to oncological patients.     

Tet-on系统诱导乳腺特异表达CUEDC2转基因小鼠的制备

目的：建立Tet-on系统诱导乳腺特异表达CUEDC2的转基因小鼠模型。方法：构建转基因表达载体,经细胞诱导表达验证后,酶切得到含有CUEDC2的线性DNA片段,并采用显微注射的方法及后续筛选鉴定,得到CUEDC2转基因小鼠。进而通过与乳腺特异表达的MMTV-rtTA转基因小鼠交配,得到CUEDC2/rtTA双阳性转基因小鼠。利用2mg/ml的多西环素（Doxycycline）诱导小鼠体内CUEDC2表达,通过Western Blot、免疫组化检测表达。结果：经诱导,CUEDC2/rtTA双阳性转基因小鼠的2个Founder的F1、F2代在转录水平和蛋白水平均成功表达CUEDC2, 并具有乳腺特异性。结论：Tet-on系统诱导乳腺特异表达CUEDC2的转基因小鼠制备成功.     

小鼠胚胎移植技术优化及对巨细胞病毒净化研究

目的 建立小鼠巨细胞病毒净化方法,以获得无MCMV感染的小鼠。方法 利用胚胎移植技术,通过使用不同激素、不同发情周期注射激素、受体鼠品系、不同的移植方法、不同时期胚胎移植,以及移植胚胎数量等对比试验,优化了净化条件。利用优化的胚胎移植净化方法,对供体鼠进行了净化。结果 SIGMA生产的激素,在10 IU剂量下超排得到的可用胚胎数量约为17枚/只;在小鼠发情间期超排得到的可用胚胎最多,超排的可用胚胎数约为23枚/只;选取C57雄性小鼠与ICR雌性小鼠交配的子一代作为受体鼠,产仔率达44.5%;输卵管移植较子宫移植效果好,产仔率为40.64%;移植2细胞胚胎的妊娠率为80%,明显优于单细胞和8细胞;受体鼠移植24枚胚胎时,产仔率达到了43.75%。利用优化的小鼠巨细胞病毒胚胎移植净化方法,净化得到了无MCMV感染的小鼠。结论 建立了小鼠巨细胞病毒净化方法,为获得无MCMV感染的小鼠种群提供了可靠的保障。     

应激引起不同年龄、性别和种类小鼠免疫器官退化的比较研究

以警告信号加足底电击的方式(简称信号电击)对不同年龄、性别和种类小鼠进行应激,每天24min,共7d。结果发现,应激后免疫器官退化,重量减轻,而且这种变化与年龄和性别有关。胸腺退化,年龄大的鼠比年龄小的鼠更明显,而脾脏则相反,年龄小的鼠更敏感。另外,胸腺的退化雄性要高于雌性,而脾脏则没有性别上的差异。从种类上看,Swiss鼠比Balb/c鼠更敏感。对淋巴结来说,这种退化没有表现出年龄、性别和种类的差异。此外,应激使胸腺、脾脏内的淋巴细胞总数和骨髓内淋巴细胞的比例减少。这一结果说明,胸腺和脾脏的退化,不是由于组织内体液的减少,而是胸腺和脾脏内淋巴细胞绝对数减少之故。