Colony-promoting activity in mice kidneys with phenylhydrazine hemolytic anemia

Aqueous anemic mice kidney extracts (MKE) were assessed colony-promoting activity (CPA) of hematopoietic progenitor cells in serum-free cultures stimulated by interleukin-3 and erythropoietin (Epo). Mice with hemolytic anemia followed by phenylhydorazine (PHZ) injection for 3 days showed a decrease in the hematocrit (25.4%) and an increase in serum Epo by 14-fold of the control on day 3 after the treatment. At 3 days, the total number of hematopoietic progenitor cells in the bone marrow of PHZ mice decreased by 67% of the control, while these cells in the spleen increased to 22-fold of the control on day 3 and 55-fold on day 6. A significant increase in CPA was observed in MKE prepared from PHZ mice kidneys. Additionally, bone marrow suppressive anemia induced by 5-fluorouracil resulted in enhanced CPA the same as for PHZ mice, but in contrast, anemia with suppression of Epo-production due to nephrotoxicity induced by cisplatin caused a decrease in CPA. These results suggest that CPA in MKE correlates with hematopoietic conditions, and may have a definite role in hematopoiesis through the function of the kidney.     

Erythropoietin delivery by genetically engineered bone marrow stromal cells for correction of anemia in mice with chronic renal failure

The goal of this research was to develop a strategy to couple stem cell and gene therapy for in vivo delivery of erythropoietin (Epo) for treatment of anemia of ESRD. It was shown previously that autologous bone marrow stromal cells (MSCs) can be genetically engineered to secrete pharmacologic amounts of Epo in normal mice. Therefore, whether anemia in mice with mild to moderate chronic renal failure (CRF) can be improved with Epo gene-modified MSCs (Epo+MSCs) within a subcutaneous implant was examined. A cohort of C57BL/6 mice were rendered anemic by right kidney electrocoagulation and left nephrectomy. In these CRF mice, the hematocrit (Hct) dropped from a prenephrectomy baseline of approximately 55% to 40% after induction of renal failure. MSCs from C57BL/6 donor mice were genetically engineered to secrete murine Epo at a rate of 3 to 4 units of Epo/10(6) cells per 24 h, embedded in a collagen-based matrix, and implanted subcutaneously in anemic CRF mice. It was observed that Hct increased after administration of Epo+MSCs, according to cell dose. Implants of 3 million Epo+MSCs per mouse had no effect on Hct, whereas 10 million led to a supraphysiologic effect. The Hct of CRF mice that received 4.5 or 7.5 million Epo+MSCs rose to a peak 54+/-4.0 or 63+/-5.5%, respectively, at 3 wk after implantation and remained above 48 or 54% for >19 wk. Moreover, mice that had CRF and received Epo+MSCs showed significantly greater swimming exercise capacity. In conclusion, these results demonstrate that subcutaneous implantation of Epo-secreting genetically engineered MSCs can correct anemia that occurs in a murine model of CRF.     

营养造血汤剂对再生障碍性贫血小鼠骨髓造血功能的影响

目的探讨营养造血汤剂对小鼠再生障碍性贫血造血功能的影响。方法 BALB/c小鼠90只,随机分为正常组、模型组及治疗组。苯、X射线、环磷酰胺联合应用的方法建立再生障碍性贫血小鼠模型,试验第8天开始,治疗组小鼠每天灌胃,给予19.76g（/kg·d）营养造血汤药液,直至第60天,观察试验小鼠的血象、骨髓象、造血干细胞集落形成;TUNEL及免疫组化法检测小鼠造血细胞凋亡以及相关调控蛋白Fas与Caspase-3的表达。结果治疗组的外周血象、骨髓有核细胞数、造血干细胞集落的形成明显高于模型组（P〈0.05）。结论营养造血汤剂对再障小鼠疗效显著,能改善骨髓增殖。     

Living kidney donation: anemia and inflammation in the early postoperative period

Studies on living donor kidney transplantation primarily address the recipients; few publications focus on kidney donors. The aim of the present study was to detect changes in and compensations of defined parameters of anemia and inflammation in the immediate postnephrectomy period. We included six living kidney donors who underwent an open anterior-extraperitoneal nephrectomy. We excluded donors with complications, such as significant blood loss or infection. Blood samples were taken before nephrectomy as well as on postoperative days 1, 3, 5, and 7, and at discharge for measurements of hemoglobin (Hb), serum erythropoietin (Epo), reticulocytes (Reti), pentraxin 3 (PTX3), and C-reactive protein (CRP). There was a significant decrease in Hb (>3 g/dL), reaching a maximum on day 3 followed by a significant threefold increase in Epo levels on day 5 and a nonsignificant elevation of Reti count. CRP increased approximately 80-fold on day 3. PTX3 showed a similar course, peaking on day 3 with an approximate 70-fold increase. After living donor nephrectomy, there was an unexpectedly pronounced inflammatory reaction in the absence of any signs of bacterial infection simultaneous with a significant decrease in Hb. These parameters improved during the hospital stay, in some cases they achieved the prenephrectomy level at discharge. These data may assist in interpreting laboratory results after nephrectomy among living kidney donors.     

Granulocyte colony-stimulating factor: release is not impaired after burn wound infection

BACKGROUND: The production of granulocyte colony-stimulating factor (G-CSF), the lineage specific essential regulator of neutrophil progenitor cell proliferation and differentiation, has been thought to be impaired in the setting of burn infection. The ability to directly measure murine G-CSF allows the further delineation of the G-CSF response in a clinically relevant model of thermal injury and infection. METHODS: We used a commercially available solid phase enzyme-linked immunoabsorbent assay to quantify G-CSF production after burn wound infection in mice. Bone marrow cells, splenic cells, and serum were obtained from BDF1 mice on day 3 after a 15% total body surface area full-thickness scald burn with or without Pseudomonas aeruginosa burn wound infection. G-CSF production of bone marrow cells or splenic cells and the serum level of G-CSF were measured. A clonogenic assay of bone marrow and spleen granulocyte-macrophage progenitor cells as well as blood leukocyte counts were also performed. RESULTS: After burn sepsis, we noted that G-CSF production of the bone marrow and spleen was significantly increased; the numbers of progenitor cells in bone marrow and spleen were markedly enhanced; serum values of G-CSF were 14 times greater than control values; serum colony-stimulating activity was greater than in control mice; and total blood leukocyte counts were significantly depressed. CONCLUSION: These findings support the notion that granulocytopoietic failure after burn sepsis is not significantly related to defective endogenous G-CSF synthesis. More likely, hyporesponsiveness of granulocyte progenitor cells to G-CSF, changes in the relative balance of granulocyte versus monocyte progenitors within the granulocyte-macrophage progenitor cell compartment, and enhanced release of monocyte lineage specific growth factors are the critical elements responsible for burn infection-induced hematopoietic failure.     

Bone marrow failure following severe injury in humans

BACKGROUND: Hematopoietic failure has been observed in experimental animals following shock and injury. In humans, bone marrow dysfunction has been observed in the red cell component and characterized by a persistent anemia, low reticulocyte counts, and the need for repeated transfusions despite adequate iron stores. While a quantitative defect in white blood cell count has not been noted, an alteration in white blood cell function manifesting as an increased susceptibility to infection is well established. Since the etiology of this anemia remains unknown and the bone marrow has been rarely studied following injury, we measured various parameters of hematopoiesis directly using bone marrow from trauma patients and tested the hypothesis that trauma results in profound bone marrow dysfunction, which could explain both the persistent anemia and the alteration in white blood cell function. METHODS: Bone marrow aspirates and peripheral blood were obtained between day 1 and 7 following injury from 45 multiple trauma patients. Normal volunteers served as controls. Peripheral blood was assayed for hemoglobin concentration, reticulocyte count, erythropoietin levels, white blood cell count, and differential. Peripheral blood and bone marrow were cultured for hematopoietic progenitors (CFU-GM, BFU-E, and CFU-E colonies). RESULTS: Bone marrow CFU-GM, BFU-E, and CFU-E colony formation was significantly reduced while peripheral blood CFU-GM, BFU-E, and CFU-E was increased in the trauma patients compared with normal volunteers. Bone marrow stroma failed to grow to confluence by day 14 in >90% of trauma patients. In contrast, bone marrow stroma from volunteers always reached confluence between days 10 and 14 in culture. The mean hemoglobin concentration and reticulocyte counts of the trauma patients were 8.6 +/- 1.0 g/dL and 2.75 +/- 0.7% respectively, while their plasma erythropoietin levels were 2 to 10 times greater than control values. CONCLUSIONS: Release of immature white blood cells into the circulation may also contribute to a failure to clear infection and an increased propensity to organ failure. Concomitantly, profound changes occur within the bone marrow, which include the increased release of erythroid and myeloid progenitors into the circulation, a decrease in progenitor cell growth within the bone marrow, and an impaired growth of the bone marrow stroma. Erythropoietin levels are preserved following trauma, implying that the persistent anemia of injury is related to the failure of the bone marrow to respond to erythropoietin.     

归芪合剂在小鼠骨髓移植后造血重建中的作用

目的探讨归芪合剂对小鼠骨髓移植后造血重建的影响。方法将BALB/c小鼠随机分为骨髓移植对照组(对照组)和骨髓移植归芪治疗组(归芪组)。对照组和归芪组的小鼠骨髓移植后,立即分别经胃饲生理盐水和归芪合剂0.4 ml,2次/d,直至小鼠处死为止。移植后第7、14、21 d时分别处死小鼠,计数其外周血白细胞、红细胞、血小板及骨髓单个核细胞,并作骨髓组织学观察。采用半定量逆转录聚合酶链反应(RT-PCR)和免疫组织化学方法检测小鼠骨髓单个核细胞CD44 mRNA基因的表达水平和骨髓组织中CD44的蛋白表达水平。结果归芪组骨髓移植后第7、14、21 d外周血细胞和骨髓单个核细胞计数,骨髓组织造血面积及巨核细胞计数,骨髓CD44 mRNA和蛋白表达水平均显著高于对照组(P<0.05或P<0.01)。结论归芪合剂能促进小鼠骨髓移植后骨髓造血重建,其机制可能是通过增强骨髓粘附分子CD44的表达水平实现的。     

联合成骨细胞移植促进骨髓移植小鼠的造血功能重建

目的 探讨联合成骨细胞移植对骨髓移植小鼠造血功能重建的影响.方法 Balb/c小鼠60只,取其中18只制备移植用骨髓有核细胞和成骨细胞.将其余42只小鼠分为3组.单纯移植组:小鼠18只,仅进行骨髓移植(BMT);联合移植组:18只,进行BMT的同时每只小鼠输入成骨细胞2×106个;正常对照组:小鼠6只,不做任何处理,仅作为移植前的正常对照.移植组小鼠在全身照射(TBI)预处理后4 h经尾静脉注入骨髓细胞2×106个.移植后第7、14和21天,分别处死移植组小鼠6只,对小鼠的外周血细胞和骨髓单个核细胞(BMMNC)进行计数,采用流式细胞术测定BMMNC中CD34+细胞的百分比,使用HPIAS-1000高清晰度彩色病理图像系统测量骨髓造血组织面积,采用免疫组化染色法测定骨髓组织微血管密度(MVD).结果 移植后第7天,单纯移植组和联合移植组小鼠外周血细胞计数及BMMNC数均明显低于正常对照(P＜0.01).第21天时联合移植组小鼠白细胞、红细胞及BMMNC数明显恢复,血小板数已接近正常对照组;单纯移植组小鼠外周血细胞数和BMMNC数虽然有所恢复,但其恢复程度明显弱于联合移植组.移植后第7、14和21天,联合移植组外周血细胞计数及BMMNC数均明显高于同期单纯移植组(P＜0.01或P＜0.05).移植后第7、14、21天,单纯移植组和联合移植组小鼠骨髓造血组织面积、BMMNC中CD34+细胞百分比及骨髓组织MVD均明显低于正常对照组(P＜0.01),但联合移植组均高于同期单纯移植组(P＜0.01或P＜0.05).结论 联合成骨细胞移植能有效促进骨髓移植小鼠骨髓造血系统的重建.

Abstract：

Objective To explore the effects of cotransplantation with osteoblasts on hematopoietic reconstitution in mice after bone marrow transplantation (BMT). Methods The typical model of syngeneic BMT was established. 18 Balb/c mice were used to prepare the bone marrow nuclear cells and osteoblasts for BMT. The 42 Balb/c mice were randomly divided into 3 group:normal group (6 mice, without any treatment), the single BMT group ( 18 mice, given 2 × 106 bone marrow nuclear cells/each mouse) and the cotransplantation group of HSC with osteoblaats (18 mice,given 2 × 106 bone marrow nuclear cells and osteoblasts/each mouse). The following factors were measured on day 7, 14, 21 after BMT: peripheral blood cells, bone marrow mononuclear cells (BMMNC), the percentage of CD34+ cells in BMMNC (assayed by flow cytometry), the hematopoietic tissue changes (detected by HPIAS-1000 image analysis system) and micro vascular density (MVD) of bone marrow tissue (with immunohistochemistry). Results The levels of periphral WBC, RBC, PLT, BMMNC in the contransplantation group were higher than those in the single BMT group (P＜0. 01 or P＜0. 05). In the contransplantation group, the percentage of CD34+ cells in BMMNC, the hematopoietic tissue area and the MVD of bone marrow were also higher than the single BMT group on the 7th, 14th, 21st day after BMT(P＜0.01 or P＜0.05). Conclusion Cotransplantation with osteoblasts could significantly promote hematopoietic reconstruction in mice after BMT. Cotransplantation may represent a promising means of achieving higher engraftment rate after BMT.     

骨髓干细胞转分化为肾祖细胞并参与修复急性肾脏损伤的研究

目的 观察骨髓干细胞是否可以向肾祖细胞转分化,成为肾脏祖细胞库的肾外来源;验证粒细胞集落刺激因子(G-CSF)是否可以促进骨髓干细胞向肾脏祖细胞的转分化,提高肾脏修复的效能.方法 6周龄全身表达绿色荧光蛋白(GFP)的C57BL/6J转基因小鼠提供骨髓,6~8周龄同种无荧光标记的C57BL/6J小鼠40只作为骨髓受体.骨髓移植前,受体小鼠接受致死剂量的γ放射线137Cs照射,骨髓重建情况经流式细胞仪检测确认.骨髓重建完毕后所有小鼠均接受单侧肾脏缺血再灌注损伤.干细胞动员效果及向肾脏归巢情况经流式细胞仪检测鉴定.损伤4、8周后取肾脏标本行免疫荧光组织化学染色,观察骨髓来源的肾脏祖细胞数以及骨髓细胞在微血管形成中的作用.损伤4周后通过组织切片免疫荧光组织化学方法观察并计数微血管细胞数.结果 G-CSF动员1 d后,分别为CD29、CD34、Sca-1、c-Kit、Flk-1阳性的干细胞占外周血非红系细胞的比例均高于对照组(P<0.05).损伤4周后,G-CSF动员组的肾脏中,骨髓来源并且分别表达Sca-1/GFP、CD29/GFP的干细胞的比例均高于对照组(P<0.05);在损伤4周及8周后,肾脏切片免疫荧光组织化学显示G-CSF动员肾脏中骨髓来源的肾祖细胞即Sca-1/GFP双阳性的细胞数量高于对照组.损伤4周后,动员组肾脏中表达CD31的微血管密度高于对照组(P<0.05).损伤4周后肾脏组织中存在CD105/GFP及α-SMA/GFP双阳性的细胞.结论 ①骨髓干细胞可以转分化为器官特异性干细胞-肾脏祖细胞;②G-CSF可以加速这一转分化的过程,并使损伤肾脏得到更好的修复.     

Reevaluation of bone marrow-derived cells as a source for hepatocyte regeneration

We have investigated the contribution of intrasplenic bone marrow transplants or in vivo mobilized hematopoietic stem cells to the formation of hepatocytes in normal and injured liver. Direct intrasplenic injections of bone marrow mononuclear cells (5 x 10(5) cells), Scal+/lin- hematopoietic stem cells (5 x 10(3)) cells, and highly purified "side population" hematopoietic stem cells (5 x 10(3)) derived from enhanced green fluorescent protein (EGFP)-transgenic mice [C57Bl/6-TgN(ActbEGFP)1Osb] were performed in normal C57Bl/6 mice (n = 6) and in C57Bl/6 mice following two thirds hepatectomy (n = 8). To test the effect of mobilized stem cells on transdifferentiation, C57Bl/6 mice (n = 12) were lethally irradiated and reconstituted with EGFP-positive bone marrow mononuclear cells in a second series of experiments. Eight to 12 weeks after bone marrow transplantation a subset of mice (n = 3 in each group) received either rhG-CSF for hematopoietic stem cell mobilization, rhG-CSF combined with an intraperitoneal application of carbon tetrachloride (CCl4) as hepatocyte regeneration stimulus, or CCl4 alone. All mice were completely perfused with PBS to remove circulating nonorgan cells for analyses 4 weeks later. Liver as well as heart, intestine, spleen, and kidney tissue was analyzed for the presence of EGFP-transgenic cells. In 100 sections (2.3 x 10(7) cells) of any recipient mouse no EGFP-positive hepatocytes were detected either by analysis of native EGFP fluorescence or by immunofluorescence analysis with anti-EGFP and antidipeptidyl peptidase (DPP) IV antibodies. EGFP-transgenic cells resembling heart, kidney, or intestinal cells could also not be proven. The results demonstrate that there is little or no contribution of bone marrow-derived cells to the regeneration of normal and injured liver in the animal models used. Thus, potential therapeutic prospects of hematopoietic stem cell therapy for liver disease have to be critically reassessed.     

Deficiency of either P-glycoprotein or breast cancer resistance protein protect against acute kidney injury

The kidney has a high capacity to regenerate after ischemic injury via several mechanisms, one of which involves bone marrow-derived (stem) cells. The ATP binding cassette transporters, P-glycoprotein and breast cancer resistance protein, are determinants for the enriched stem and progenitor cell fraction in bone marrow. Because they are upregulated after acute kidney injury, we hypothesized that both efflux pumps may play a role in protecting against renal injury. Surprisingly, transporter-deficient mice were protected against ischemia-induced renal injury. To further study this, bone marrow from irradiated wild-type mice was reconstituted by bone marrow from wild-type, P-glycoprotein- or breast cancer resistance protein-deficient mice. Four weeks later, kidney injury was induced and its function evaluated. Significantly more bone marrow-derived cells were detected in kidneys grafted with transporter-deficient bone marrow. A gender mismatch study suggested that cell fusion of resident tubular cells with bone marrow cells was unlikely. Renal function analyses indicated an absence of renal damage following ischemia-reperfusion in animals transplanted with transporter-deficient bone marrow. When wild-type bone marrow was transplanted in breast cancer resistance protein-deficient mice this protection is lost. Furthermore, we demonstrate that transporter-deficient bone marrow contained significantly more monocytes, granulocytes, and early outgrowth endothelial progenitor cells.     

Parathyroid hormone regulates the distribution and osteoclastogenic potential of hematopoietic progenitors in the bone marrow

Parathyroid hormone (PTH) increases both the number of osteoclast in bone and the number of early hematopoietic stem cells (HSCs) in bone marrow. We previously characterized the phenotype of multiple populations of bone marrow cells with in vitro osteoclastogenic potential in mice. Here we examined whether intermittent administration of PTH influences these osteoclast progenitor (OCP) populations. C57BL/6 mice were treated with daily injections of bPTH(1–34) (80 µg/kg/day) for 7 or 14 days. We found that PTH caused a significant increase in the percentage of TN/CD115⁺CD117^high and TN/CD115⁺CD117^int cells (p < .05) in bone marrow on day 7. In contrast, PTH decreased the absolute number of TN/CD115⁺CD117^low cells by 39% on day 7 (p < .05). On day 14, there was no effect of PTH on osteoclast progenitor distribution in vivo. However, PTH treatment for 7 and 14 days did increase receptor activator of NF‐κB ligand (RANKL)– and macrophage colony‐stimulating factor (M‐CSF)–stimulated in vitro osteoclastogenesis and bone resorption in TN/CD115⁺ cells. In the periphery, 14 days of treatment increased the percentage and absolute numbers of HSCs (Lin^?CD117⁺Sca‐1⁺) in the spleen (p < .05). These data correlated with an increase in the percent and absolute numbers of HSCs in bone marrow on day 14 (p < .05). Interestingly, the effects on hematopoietic progenitors do not depend on osteoclast resorption activity. These results suggest that in vivo PTH treatment increased in vitro osteoclastogenesis and resorption without altering the number of osteoclast precursors. This implies that in vivo PTH induces sustained changes, possibly through an epigenetic mechanism, in the in vitro responsiveness of the cells to M‐CSF and RANKL. © 2011 American Society for Bone and Mineral Research.     

Effect of burn injury on granulocyte and macrophage production

Using a model of uncomplicated burn injury in mice, we assayed the bone marrow and splenic production of granulocytes and macrophages after burn injury. The effects of burn size and burn wound excision and closure were studied. Using an in vitro quantitative clonal culture technique for granulocyte/macrophage progenitor cells (GM-CFC), myeloid precursors were directly assayed. Burns of a 10% body surface area were equal to burns of larger magnitude for effects on marrow and splenic granulocyte/macrophage production. The total peripheral blood leukocyte and lymphocyte counts were depressed at days 1 and 4 postburn but were elevated at days 8 and 12. Granulocytes, however, remained significantly increased at days 8 and 12. The bone marrow response to burning showed an initial depression in marrow cellularity on day 1 with return to normal values by days 8 and 12. The numbers of GM-CFC were significantly elevated on days 4-12 with a near threefold increase in the number of GM-CFC 12 days following burn injury. The splenic response to burn injury was characterized by a decrease in the splenic index on day 1 but then a persistent increase at days 8 and 12. Total splenic cellularity was depressed on day 1 but significantly increased at days 8 and 12. The total number of splenic GM-CFC was increased on days 4-12 with a 100-fold increase on day 8. The immediate or delayed excision of the burn wound did not alter marrow or splenic response to burning. We conclude that following a cutaneous injury there is a marked alteration in the generation of the phagocytic cells of the granulocyte and macrophage series and that this response is secondary to the wounding process.     

Effect of anemia and renal cytokine production on erythropoietin production during blood-stage malaria

BACKGROUND: Renal dysfunction and severe anemia are clinical complications of blood-stage malaria. Erythropoietin (Epo) is a hormone produced by the kidney and plays an essential role in stimulating erythrocyte production. Renal dysfunction in malaria is associated with changes in renal cytokine levels, which may affect the production of Epo and the alleviation of anemia. METHODS: Resistant C57BL/6 (B6) and susceptible A/J mice were infected with Plasmodium chabaudi AS. The levels of Epo and cytokines were measured by enzyme-linked immunosorbent assay (ELISA) and the degree of anemia was determined by hematocrit. Regression analyses were employed to estimate the influences of anemia and renal cytokines on the production of Epo during infection. RESULTS: A/J mice developed higher peak parasitemia, more severe anemia, and succumbed as compared to B6 mice, which survived the infection. B6 mice had higher levels of renal tumor necrosis factor-alpha (TNF-alpha) and interleukin (IL)-10, whereas A/J mice had higher levels of IL-12p70, granulocyte-macrophage colony-stimulating factor (GM-CSF), IL-4, and Epo. Regression analyses revealed that kidney Epo levels were influenced most strongly by changes in hematocrit levels. In addition, albeit to a much weaker degree, kidney Epo levels correlated negatively with GM-CSF levels but positively with IL-10 levels. CONCLUSION: Blood-stage malaria infection modulates the production of renal pro- and anti-inflammatory cytokines in resistant versus susceptible strains of mice differentially. However, despite the fluctuations of renal cytokines, the degree of anemia is the main determinant for Epo production during blood-stage malaria while kidney cytokines may exert secondary influences.     

Ex vivo expansion and transplantation of hematopoietic stem/progenitor cells supported by mesenchymal stem cells from human umbilical cord blood

Human mesenchymal stem cells (MSCs) are multipotential and are detected in bone marrow (BM), adipose tissue, placenta, and umbilical cord blood (UCB). In this study, we examined the ability of UCB-derived MSCs (UCB-MSCs) to support ex vivo expansion of hematopoietic stem/progenitor cells (HSPCs) from UCB and the engraftment of expanded HSPCs in NOD/SCID mice. The result showed that UCB-MSCs supported the proliferation and differentiation of CD34+ cells in vitro. The number of expanded total nucleated cells (TNCs) in MSC-based culture was twofold higher than cultures without MSC (control cultures). UCB-MSCs increased the expansion capabilities of CD34+ cells, long-term culture-initiating cells (LTC-ICs), granulocyte-macrophage colony-forming cells (GM-CFCs), and high proliferative potential colony-forming cells (HPP-CFCs) compared to control cultures. The expanded HSPCs were transplanted into lethally irradiated NOD/SCID mice to assess the effects of expanded cells on hematopoietic recovery. The number of white blood cells (WBCs) in the peripheral blood of mice transplanted with expanded cells from both the MSC-based and control cultures returned to pretreatment levels at day 25 posttransplant and then decreased. The WBC levels returned to pretreatment levels again at days 45-55 posttransplant. The level of human CD45+ cell engraftment in primary recipients transplanted with expanded cells from the MSC-based cultures was significantly higher than recipients transplanted with cells from the control cultures. Serial transplantation demonstrated that the expanded cells could establish long-term engraftment of hematopoietic cells. UCB-MSCs similar to those derived from adult bone marrow may provide novel targets for cellular and gene therapy.     

Effects of prolonged nitrous oxide exposure on hemopoietic stem cells in splenectomized mice

We have demonstrated in previous papers that prolonged nitrous oxide exposure suppresses murine hemopoiesis more in the spleen than in the bone marrow and that this is caused by the suppression of the hemopoietic supportive activity of the microenvironment. In the present study, we used splenectomized mice as an experimental model to investigate the direct effect on bone marrow function of prolonged nitrous oxide inhalation. All of the experimental mice were splenectomized at the age of 4 wk. Half of the experimental mice were continuously exposed to 50% nitrous oxide, and the remainder were continuously exposed to air as controls, starting 3 wk after splenectomy and lasting 14 days, and the numbers of pluripotent hemopoietic stem cells (CFU-S) and granulocyte-macrophage progenitor cells (GM-CFC) in bone marrow were counted. The numbers of pluripotent hemopoietic stem cells and granulocyte-macrophage progenitor cells in the bone marrow of mice exposed to air showed no significant change. The numbers of these two types of cells found in nitrous oxide-exposed mice were approximately 60% of control levels. These data are almost the same as our previously reported bone marrow data obtained in nonsplenectomized mice exposed to nitrous oxide for 14 days. The present results suggest that the marked decrease in the number of splenic hemopoietic stem cells in our previous data is not a result of migration of the cells to bone marrow, and that nitrous oxide directly affects murine bone marrow hemopoiesis.     

Promotion of xenogeneic hematopoietic chimerism in rodents by mononuclear phagocyte depletion

Cheng J, Glaser RM, Kruger-Grey H, White-Scharf ME, Cooper DKC, Thall AD. Promotion of xenogeneic hematopoietic chimerism in rodents by mononuclear phagocyte depletion. Xenotransplantation 2002; 9: 402–409. © Blackwell Munksgaard, 2002
The successful establishment of tolerance toward pig tissues in primates through hematopoietic progenitor cell engraftment is restricted by the rapid disappearance of these cells in the recipient following infusion. We developed and tested the hypothesis that phagocytes of the reticuloendothelial system are responsible for the rapid clearance of infused pig hematopoietic cells using a mouse model. Mice received non-myeloablative conditioning and, on various days, were injected with medronate-encapsulated liposomes (M-L) or control blank liposomes, followed by the intravenous infusion of miniature swine hematopoietic cells. M-L were well-tolerated in mice (n=100) at levels that deplete mononuclear phagocytes. Depletion of mononuclear phagocytes in normal Balb/c mice as well as in severe combined immune deficient mice increased the accumulation of pig hematopoietic cells in the bone marrow (BM) by 10-fold when measured 24 h after the infusion of the cells. Colony-forming unit analysis showed an increased accumulation of pig hematopoietic progenitors in the BM of mice that were infused with medronate-liposomes. We conclude that depletion of mononuclear phagocytes by M-L has the potential to lower the barrier to the establishment of mixed chimerism and tolerance induction in xenotransplantation.     

Influence of cytarabine and cyclophosphamide on the disposition kinetics of cyclosporin A after bone marrow transplantation

The blood concentration of cyclosporin A (CyA) often gradually increases or is unstable in the early period of immunotherapy in bone marrow transplantation patients. In the protocol for bone marrow transplantation, pretreatment with cytarabine (Ara-C) and cyclophosphamide (CPA) is employed. We examined the influence of Ara-C and CPA on the disposition kinetics of CyA, in using rats to define the mechanism for the observation. Rats were intravenously administered daily with Ara-C (120 mg/kg/day) or CPA (60 mg/kg/day) intravenously for 2 days and were then intravenously given CyA (10 mg/kg). The blood concentration of CyA after intravenous administration of CyA at 1 day after the last administration of CPA was significantly lower and the total clearance was significantly larger than those in the vehicle control rats, while the blood concentration and the pharmacokinetic parameters of CyA were unchanged after Ara-C treatment. The expression of mdr1a, mdr1b, and CY3A2 mRNAs, and the levels of the corresponding proteins in the liver were increased after the CPA treatment. These CPA-induced changes were almost fully reversed to the control levels by 2 weeks. Thus, our results indicate that the decrease of blood CyA concentration induced is a consequence of the induction of P-glycoprotein and CYP3A in the liver by the CPA treatment , and these changes are reversed within 2 weeks after the transplantation.     

HSV-sr39TK-GCv/ACV系统抑制小鼠异基因骨髓移植后移植物抗宿主病

目的 研究突变型单纯疱疹病毒胸苷激酶一更昔洛韦/阿昔洛韦(HSV-sr39TK-GCV/ACV)系统对小鼠异基因骨髓移植后移植物抗宿主病(GVHD)的影响.方法 采用改良的磷酸钙沉淀法,以携带HSv-sr39TK基因的慢病毒感染C57BL/6小鼠的脾淋巴细胞.制得sr39TK+T淋巴细胞.以C57BL/6小鼠为供者,Balb/c小鼠为受者进行骨髓移植,受者移植前接受60>Coγ射线照射.实验分6组进行:(1)GCV组共30只小鼠,均于骨髓移植的同时输注sr39TK+T淋巴细胞.其中10只于骨髓移植当天至第6天腹腔注射GCV 0.5 mg/d,10只于骨髓移植后第7～13天腹腔注射GCV0.5 mg/d,10只于骨髓移植后第12～18天腹腔注射GCV 0.5 nag/d;(2)ACV组共30只小鼠,骨髓移植与sr9TK+T淋巴细胞输注同GCV组,其中10只于骨髓移植当天至第6天腹腔注射ACV 0.5mg/d,10只于骨髓移植后第7～13天腹腔注射ACV 0.5 mg/d,10只于骨髓移植后第12～18天腹腔注射ACV 0.5 mg/d;(3)移植对照组仅行骨髓移植;(4)脾细胞对照组行骨髓移植和脾淋巴细胞输注;(5)GCV对照组在脾细胞对照组的基础上于骨髓移植后第7～13天腹腔注射GCV 0.5 mg/d.(6)sr39TK对照组行骨髓移植和sr9TK+T淋巴细胞输注.观察各组受者的存活时间、GVHD的发生情况及程度.结果 GCV对照组、sr9TK对照组、睥细胞对照组和移植对照组小鼠均于骨髓移植后19 d内死亡.GCV组移植当天用药者、第7天用药者和第12天用药者的存活时间分别为(36.70±5.20)d、(40.30±4.69)d和(27.10±4.85)d.ACV组移植当天用药者、第7天用药者和第12天用药者的存活时间分别为(36.50±5.26)d、(46.20±3.61)d和(30.90±5.21)d.GCV组和ACV组受者的存活时间均长于4个对照组(P<0.01),GCV组和ACV组中第7天用药者的存活时间和5(1 d存活率优于其它各时间用药者,差异有统计学意义(P<0.05),而ACV组第7天用药者又明显优于GCV组第7天用药者(P<0.05).4个对照组小鼠移植后10～12 d均开始出现Ⅲ～Ⅳ级GVHD.GCV组和ACV组死亡小鼠可见Ⅱ～Ⅳ级GVHD.而该两组中长期存活受者仅有Ⅰ～Ⅱ级GVHD.结论 HSV-sr9TK-GCV/ACV系统对小鼠异基因骨髓移植后的GVHD有一定的抑制作用;ACV的效果优于GCV;移植后7 d时应用ACV的效果较佳.     

Erythropoietin enhances recovery after cisplatin-induced acute renal failure in the rat.

BACKGROUND: Erythropoietin (Epo) is a growth factor whose synthesis mainly takes place in the kidney. Epo has been shown to support the growth not only of erythroid progenitor cells but also of certain other cell types. We attempted to establish whether Epo enhances the recovery from acute renal failure induced by cisplatin. METHODS: Sprague-Dawley rats were randomized into three groups. In the cisplatin group, animals received one intraperitoneal injection of cisplatin (6 mg/kg) and a daily injection of placebo for 9 days. In the cisplatin+Epo group, animals received intrapertoneal cisplatin and a daily injection of Epo (100 IU/kg) for 9 days. In the control group, animals received both placebo preparations alone. Para-aminohippuric acid and inulin clearances were determined after 4 and 9 days to evaluate renal blood flow and glomerular filtration rate. In addition, light microscopy and immunohistochemistry examinations were performed, and in situ proliferating cell nuclear antigen (PCNA) staining was done to estimate the degree of renal tubular cell regenerative activity. The potential role of epithelial growth factor (EGF) was evaluated by semi-quantitative assessment of EGF immunostaining. RESULTS: Renal blood flow and glomerular filtration rate decreased significantly in cisplatin and cisplatin+Epo groups versus control group at day 4. However, at day 9, they both were significantly greater in cisplatin+Epo-treated animals than in rats that had received cisplatin alone. Tubular cell regeneration was significantly enhanced at day 4 in cisplatin+Epo group, compared with cisplatin and control groups respectively. EGF immunostaining was not significantly different between the three groups. CONCLUSION: Epo significantly enhanced the rate of recovery from acute renal failure induced by cisplatin. PCNA staining indicated that Epo might act directly via stimulation of tubular cell regeneration.