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1.
THE ROLE OF BONE MARROW OF X-IRRADIATED MICE IN THYMIC RECOVERY   总被引:1,自引:0,他引:1  
The influence of the bone marrow on the repopulation of the thymus in X-irradiated mice has been investigated.
It was observed that the thymus and a certain population of bone marrow lymphocytic cells were repopulated in parallel in a cyclic fashion. This occurred either after a single exposure of mice to 400 R or after serial weekly X-ray treatments with 170 R. Lethally irradiated recipients which were grafted with bone marrow cells obtained 12-24 days after four weekly irradiations of donor mice with 170 R also exhibited a cyclic repopulation of both the thymus and the bone marrow lymphocytic population. In contrast, mice which were transplanted with bone marrow cells from unirradiated donors, containing an equal number of stem cells (CFU), exhibited a continuous rather than a cyclic recovery of both cell populations. the bone marrow stem cells of mice recovering from X-irradiation were found to have a decreased proliferative activity, since they produced significantly smaller spleen colonies in lethally irradiated recipients than marrow cells from unirradiated mice.
The results were interpreted as indicating that the bone marrow lymphocytic cells may act as thymic precursor cells and that thymic lymphopoiesis is dependent on the presence of such cells. Evidently, the production of lymphocytic cells will decrease when the stimulus for granulocyte production increases due to the limited proliferative activity of the surviving bone marrow stem cells after irradiation. This may result in a cyclic variation of the production of bone marrow lymphocytic cells and it follows that thymic lymphopoiesis will run parallel.  相似文献   

2.
目的探讨当归多糖(APS)对放射损伤小鼠骨髓单个核细胞(BMNC)黏附分子表达及细胞周期的影响,旨在阐明APS防护辐射性造血损伤的分子机制。方法建立小鼠放射损伤模型后连续给予不同剂量APS 13d,在不同时间点进行外周血白细胞、红细胞、血小板及BMNC计数;流式细胞术检测小鼠Sca-1+BMNC黏附分子CD44和CD49d表达及BMNC细胞周期的变化;Western blot和RT-PCR方法分别检测小鼠BMNC细胞周期蛋白(Cyclin)D2 mRNA和蛋白表达水平的改变。结果与正常组比较,NS组外周血WBC、RBC、PLT及BMNC计数明显减少,Sca-1+BMNC CD44、CD49d表达明显下降,G0/G1期细胞比例显著增加,CyclinD2 mRNA和蛋白表达水平明显降低。2 mg/kgAPS组和8 mg/kgAPS组能增加外周血各指标及BMNC计数,第7d明显提高Sca-1+BMNC黏附分子CD44、CD49d的表达水平,第14d能降低Sca-1+BMNC黏附分子CD44、CD49d的表达水平,降低G0/G1期细胞比例,提高CyclinD2mRNA和蛋白表达水平。结论当归多糖能通过调节放射损伤小鼠Sca-1+BMNC黏附分子的表达水平、上调BMNC的CyclinD2 mRNA和蛋白表达水平来加速BMNC G1期向S期的转换,促进造血恢复。  相似文献   

3.
Following Colcemid administration, mitoses accumulate preferentially in the subendosteal region of the bone marrow of the mouse. This finding suggests that the most rapidly proliferating cells are localized to the subendosteal region, and complements previous radioautographic studies which have demonstrated a corresponding labelling gradient in the marrow. Quantitative estimates of cell cycle time by the stathmokinetic method were precluded by the presence of significant Colcemid induced interphase cell loss. Colcemid also affected cell differentiation in the marrow. Following Colcemid administration there was a fall in mature granulocytes in the marrow, and a concommitant rise in marrow megakaryocytes.  相似文献   

4.
本研究通过传代培养小鼠骨髓内皮细胞系细胞,收集无血清条件培养液(mBMECCM),将其作多级串联超滤,获得分子量大于10、3~10、1~3、05~1kD和小于05kD超滤组分。进行粒巨噬系造血祖细胞集落形成试验,检测了它们的作用。mBMECCM和3~10kD组分对粒巨噬系祖细胞(CFUGM)生长未见明显影响,而分子量大于10kD和05~1kD组分促进CFUGM的增殖,分子量1~3kD和小于05kD组分则抑制CFUGM的增殖。这4种超滤组分对CFUGM生长的效应均有剂量依赖性。这些结果提示,在体外培养条件下,小鼠骨髓内皮细胞分泌若干种活性成分,分别对CFUGM的生长起促进或抑制作用  相似文献   

5.
Following syngeneic or autotransplantation of hemopoietic tissue to a heterotopic location, bone formation has been observed to occur in the implanted tissue. the characteristics of the cell residing in hemopoietic tissue with bone forming potential (preosteoblast) are unknown. to define some properties of this cell, its response to X-irradiation and cyclophosphamide (CTX) was compared to the response of the hemopoietic stem cell. Adult, male rats were exposed to 900 R whole body X-irradiation or 220 mg/kg of intraperitoneal CTX. With either treatment the dose was sufficient to kill the animals by bone marrow failure. At intervals following the X-irradiation or CTX, hemopoietic tissue was examined for the presence of viable hemopoietic stem cells and preosteoblasts. Following X-irradiation, viable hemopoietic stem cells and preosteoblasts could not be detected. Following CTX these cells could be detected. It is suggested that in the rat CTX at 220 mg/kg, although causing death by bone marrow failure, does not reduce the population of the preosteoblast or hemopoietic stem cell as effectively as 900 R X-irradiation.  相似文献   

6.
目的:应用双哌达莫(DPM)、腺苷(ADO)与ADO拮抗剂茶碱(TH)治疗博莱霉素(BLE)肺纤维化小鼠,观察肺、脾等病理变化,探讨肺纤维化发病机理,方法:实验第1天100只小鼠经气管注入BLE8.5mg.kg^-1,随机分BLE,DPM,ADO和TH四组,第2天起分别给予NS(100μl.d^-1)、DPM、ADO和TH,剂量为50mg.kg^-1.d^-1,共7天,第4-30天内处死动物,组织化学法观察肺内纤维变化与脾、胸腺、骨髓病理学改变。结果:BLE组和TH组第4-6生脾。胸腺须质与骨髓中许多基质细胞坏死导致组织严重疏松,BLE组第20天后脾与胸腺逐渐萎缩,肺与脾内网状纤维大量增加。DPM组与ADO组第4-6天脾、骨髓增死基质细胞较少。第30天肺未发生纤维化,淋巴器官未萎缩。结论:BLE能致脾、,骨髓等基质细胞大量坏死与严重组织疏松,内、外源性ADO能轻度减少基质细胞坏死,促进淋巴组织与造血组织增生,抑制BLE诱导的肺纤维化与淋巴器官萎缩。  相似文献   

7.
The colony-forming ability of haematopoietic cells of W anaemic mice was examined on the macrophage layer formed in the peritoneal cavity of mice. Bone marrow cells of W anaemic mice formed a considerable number of colonies on the macrophage layer, notwithstanding they did not form any colonies in the spleen of the same recipients. As the colony-forming ability of the bone marrow cells was not reduced by the incubation with 3H-thymidine, most of the cells which formed colonies on the macrophage layer seemed to stay in G0 state. The interrelationship between the spleen colony-forming cells, the macrophage-layer colony-forming cells, and in vitro colony-forming cells was discussed.  相似文献   

8.
本文以101/E1和C3H/E1的杂种第一代小鼠为材料,一次性腹腔注射秋水仙碱(COM)后,于不同时间取材,观察分析了小鼠骨髓细胞有丝分裂指数(MI)和C-有丝分裂的变化。结果表明:COM处理后2小时,MI和C-有丝分裂均已达到最高;并随处理时间延长而降低;至18小时,MI已降到(1mg/kg)或显著低于(3mg/kg)对照水平,而C-有丝分裂仍显著高于对照组。并对COM影响MI的可能机制以及C-有丝分裂效应与非整倍体诱导活性之间的关系进行了讨论。  相似文献   

9.
小鼠骨髓血红蛋白含量的变化可以间接地反映骨髓微循环系统形态和功能的状况。按Burger and Knyszynski(1969)方法操作繁复,限制了它的推广应用及正常值的问世。最近,我们建立的简易测定方法,为成批标本的测定和正常值的确定创造了条件。 正常小鼠骨髓血红蛋白含量测定的目的:1)在较大量标本的测定中进一步验证该方法的可靠性;2)确定青、成年小鼠骨髓血红蛋白的正常值范围;3)分析其可能的影响因素,以便更好地控制实验条件和判断骨髓微循环障碍的程度。  相似文献   

10.
目的:探讨人脐带清(CBS)在骨髓造血祖细胞培养中的效应。方法:用人骨髓细胞进行CFU、GM、VFU-E、BFU-E、CFU-GEMM培养。结果:CBS能直接刺激骨髓细胞CEU-GM的形成。与血型相同害无关。四人份以上的混合CBS(MCBS),刺激活性高且稳定。10%MCBS相当于65.6μg/L GM-CSF、0.23、0.3、0。.46kU/L EpO对CFU-GM、CFU-E、BFU-E、C  相似文献   

11.
杜勋湘  徐有恒 《生理学报》1989,41(6):597-601
用组胺H_2受体拮抗剂(甲氰咪胍或呋喃硝胺)处理正常和亚致死量γ-射线照射小鼠,探讨正常体内造血和再生骨髓中造血重建与组胺受体的关系。发现非毒性剂量的甲氰咪胍对正常小鼠骨髓多能造血干细胞(CFU-s)无抑制作用,但可抑制小鼠体内粒单系祖细胞(CFU-GM)的生长和亚致死量照射后CFU-s产率的恢复。组胺可能与骨髓的再生有关,组胺H_2受体拮抗剂可抑制骨髓的造血重建。  相似文献   

12.
The number of nucleated bone marrow cells, the number of CFU and the number of DNA-synthesizing cells in the mouse were studied after injection of hydroxyurea. It was found that one injection provokes a partial synchronization of surviving cells and probably stimulates the transition of CFU from the quiescent to the cycling state. the changes of the proportion of CFU in the S phase makes it possible to estimate approximately a cell cycle duration of about 12 hr.  相似文献   

13.
14.
本实验以Dexter培养体系作小鼠胎肝和骨髓造血基质细胞贴壁培养。在所获的基质细胞贴壁层上作红系造血祖细胞集落培养,观察两种来源造血基质细胞对红系集落生长的影响。实验结果表明,胎肝造血基质细胞贴壁层能明显促进早期红系造血祖细胞(BFU-E)形成集落,却不明显影响晚期红系造血祖细胞(CFU-E)的生长。成年小鼠骨髓造血基质细胞贴壁层对BFU-E和CFU-E均有刺激生长的作用;但对前者生长的刺激性影响较胎肝造血基质细胞贴壁层为弱。造血基质细胞贴壁层对红系集落生长的促进作用主要是通过体液因子实现的,细胞间短距离调节的影响亦不能除外。  相似文献   

15.
本文研究了注射含微囊藻毒素的微囊藻细胞抽提掖对小鼠血液以及免疫系统的亚慢性毒性作用。实验分为3个处理组和1个对照组(每组10只昆明小鼠,雌雄各半),采用腹腔注射的染毒方法对3个处理组进行暴露,剂量分别为2.4、4.8 和 9.6 μg microcystin-LR/kg body weigh,对照组注射等量的生理盐水,连续注射14d。实验结果表明,14d 染毒后,小鼠的肝体比和脾体比都明显增大(p < 0.05), 同时在9.6 μg/kg处理组,血清丙氨酸转移酶、天冬氨酸转移酶、乳酸脱氢酶和碱性磷酸酶活性与对照相比明显升高,但血清总蛋白、白蛋白和白蛋白/球蛋白比率下降。这些指标的变化说明,含微囊藻毒素的微囊藻细胞提取液对处理组小鼠肝脏造成了损伤,肝组织学观察也印证了这个结果,在处理组小鼠肝组织有明显的水样变性。另外,9.6 μg/kg处理组小鼠血液白细胞数量比对照组明显减少。组织细胞学观察发现,处理组小鼠脾脏也有明显的损伤。该实验结果说明,含微囊藻毒素的微囊藻细胞抽提液对小鼠的血液和免役系统都产生了一定程度的损伤。  相似文献   

16.
A possible regulatory action of phagocytic cells on erythropoiesis was investigated by infusion of inert polystyrene latex particles (LAT). LAT appeared to induce changes in the femoral content of erythroid progenitor cells. These changes were most pronounced in primitive erythroid progenitor cells (BFUe) and appeared to be gradually damped in more differentiated populations (CFUe and erythroblasts). LAT did not influence granulocyte/macrophage progenitor cells (CFUc). The effects of LAT could not be attributed to changes in the systemic erythropoietin (EP) concentration. Administration of dexamethason nullified the effect of low doses of LAT, suggesting that phagocytosis of the particles is essential to the observed effects. Erythroid burst formation was previously found to be dependent on a bone marrow associated activity, termed BFA (burst feeder activity). BFA acts as an in vitro inducer of EP-responsiveness in BFUe. In this study it was found that LAT-induced changes in femoral erythroid progenitor cell content were characteristically preceded by corresponding changes in BFA. It was concluded that BFA-associated cells probably play a role in vivo in the early differentiation of erythroid progenitor cells. The present data are interpreted as direct in vivo evidence supporting a two-step regulatory model operating in erythropoiesis and provide evidence that phagocytic cells are a component of the erythroid haemopoietic inductive micro-environment.  相似文献   

17.
DNA-synthesis (S) times of myelocytes and nucleated erythroid cells in the bone marrow of healthy mice as well as mice bearing advanced Ehrlich ascites tumors were measured with the aid of a combined in vivo-in vitro double isotope labeling technique. Neither the S-period nor the rate of proliferation of these cells were influenced by the presence of the tumor in these hosts. This finding discounts the possibility that the marked retardation of DNA-synthesis and proliferation rate observed in the tumor cells themselves with advancing tumor-age is a nonspecific effect of the nutritional deterioration in the host.  相似文献   

18.
Both murine and human bone marrow cells were cultured in plasma clots which were formed inside diffusion chambers implanted into cyclophosphamide- and saline-treated mice. After an initial fall, the number of mouse bone marrow cells and numbers of mouse myeloid stem cells (CFU-C) and agar cluster-forming units rose faster in the cyclophosphamide-treated animals. These hosts also favored formation of myeloid (CFU-D-G) and erythroid (CFU-D-E) colonies and myeloid clusters in the plasma clot. The number and growth rate of mouse CFU-D-G were higher than those of CFU-C from the same marrow population. These observations suggest the existence of humoral factors stimulating granulocyte progenitor cell replication and differentiation. At its best the increment of CFU-D-E number was equivalent to that caused by a single 0·1 unit erythropoietin dose. Culture of normal human marrow cells resulted in colonies in the plasma clot containing only granulocytes and macrophages. Cyclophosphamide-treated host animals were essential for human CFU-D-G development. Plating efficiency for human marrow myeloid colonies was better in the conventional in vitro agar cultures than in diffusion chambers.  相似文献   

19.
The aim of this study was to examine the effects of low-frequency, low-energy pulsed electromagnetic fields (PEMFs) on cell proliferation and differentiation in rat osteoblast primary cultures. Cells were obtained from normal and osteopenic rat bone and were named NB and OB, respectively. The osteoblastic phenotype was assessed by stimulation with 1,25(OH2) vitamin D3. NB and OB cells were seeded in multiwell plates and exposed to PEMFs for two different periods. Control cultures of both groups were incubated under the same conditions, with the pulse generator off. Assessment of PEMF effects was performed for the following parameters for each culture: alkaline phosphatase (ALP) activity, osteocalcin level, and MTT test. Results showed that OB and NB cell proliferation was significantly improved (p < 0.03, p = 0.04 respectively) after 48 h of PEMF exposure. Osteocalcin production of OB after 5 days of PEMF exposure was significantly higher than normal (p = 0.007) and osteopenic (p = 0.033) bone-derived controls. These results show that PEMFs act on osteopenic bone-derived osteoblasts, stimulating proliferation of cells and then, after a longer exposure, activating them.  相似文献   

20.
为探讨逆转录病毒介导的TPO基因在人骨髓基质细胞系HFCL中的表达,利用脂质体法将含TPO基因的逆转录病毒载体导入HF-CL细胞中,RT-PCR和基因组DNAPCR分析证实mRNA水平有表达,基因组中整合有Neo基因和TPO基因。TPO依赖细胞株TD-3检测生物学活性表明转染的骨髓基质细胞分泌TPO。上述结果为进一步研究转基因骨髓基质细胞对造血细胞的调控作用提供了必要的基础资料。  相似文献   

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