羟乙基淀粉沉淀(HES)法分离脐血造血干细胞的临床优势分析

目的:探讨羟乙基淀粉沉淀(HES)法分离脐血单个核细胞(MNCs)的效果。方法:采集脐血31份,应用羟乙基淀粉(HES)沉淀飞和密度离心(Ficoll)法分离脐血MNCs,、纯化CD3+细胞、CD14+细胞、CD34+细胞,以台盼蓝拒染法检测细胞活力。结果:HES法MNCs回收率、CFU-GM计数高于Ficoll法(85.29±3.79 VS 47.06±4.61,t=35.67,P0.05;67.31±11.57/l×105MNCs VS28.54±6.39/l×105MNCs,t=16.33,P0.05);HES法分离的MNCs中CD3+、CD14+、CD34+细胞数均高于Ficoll法(t=5.76,t=2.51,t=6.67,P0.05)。结论:HES法分离MNCs可获得较好的回收率,是人脐血干细胞理想的分离方法。     

Large-scale Ficoll gradient separations using a commercially available,effectively closed,system

Background aimsMultiple cell-therapy products require density separation as a part of manufacturing. The traditional method for Ficoll separation, layering cell suspensions over Ficoll in tubes, followed by centrifugation and collection of cells from the interface, is too cumbersome and poses too high a risk of contamination for clinical-scale use. Recently, a system for clinical-scale Ficoll gradient applications has been introduced (Sepax?) but this system has limited availability and is costly.MethodsFor preparations of mononuclear cells (MNC) for dendritic cell (DC) production, we developed a Ficoll separation protocol that employs the Haemonetics? Cell Saver5? surgical blood salvage and wash instrument. This system uses standard blood bags and tubing, has single-use components, and is effectively closed. We analyzed 37 recent separation processes using this instrument and protocol. We measured depletion of red blood cells (RBC) and polymorphonuclear leukocytes (PMN), and recovery of CD14⁺ monocytes and MNC.ResultsStarting cell counts were 14.6 ± 8.0 (×10⁹). Total cell recovery was 49.2 ± 15.2%, RBC depletion was 88.4 ± 2.8%, PMN depletion was 86.9 ± 6.1%, MNC recovery was 63.6 ± 5.0% and CD14⁺ monocyte recovery was 75.3 ± 9.9%.ConclusionsThe Cell Saver5? is relatively inexpensive to purchase and use. The instrument and its disposables are licensed by the United States Food and Drug Administration (FDA) for intra-operative blood salvage, and we have obtained approval for investigational use. Our method with this instrument has proven to be simple and efficient for clinical-scale Ficoll separations.     

他汀类药物对外周血内皮祖细胞的影响

本文旨在探讨他汀类药物氟伐他汀对外周血内皮祖细胞(endothelial progenitor cells,EPCs)数量和功能的影响.用密度梯度离心从外周血获取单个核细胞,将其接种在人纤维连接蛋白(human fibronectin)包被的培养板中,培养7 d后,收集贴壁细胞,加入不同浓度氟伐他汀(分别为0.01、0.1、1、10μmol/L)和辛伐他汀(1 μmol/L),培养一定的时间(6、12、24、48 h).用激光共聚焦显微镜鉴定FITC-UEA-I和DiI-acLDL双染色阳性细胞为正在分化的EPCs,用流式细胞仪检测其表面标志进一步鉴定EPCs,在倒置荧光显微镜下计数.采用MTT比色法、改良的Boyden小室、粘附能力测定实验和体外血管生成试剂盒观察EPCs的增殖能力、迁移能力、粘附能力和体外血管生成能力.结果显示,氟伐他汀可显著增加外周血EPCs的数量,并且EPCs数量随氟伐他汀浓度增加及作用时间延长而增加,1 μmol/L浓度氟伐他汀作用24h对EPCs的数量影响最为显著(较对照组增加15倍,P＜0.05).在动物实验中,喂养氟伐他汀3周后,大鼠的EPCs也较对照组增加2倍(P＜0.05),进一步支持了体外实验的结果.氟伐他汀和辛伐他汀也显著改善外周血EPCs的粘附能力、迁移能力、增殖能力和体外血管生成的能力,相同浓度的氟伐他汀和辛伐他汀(1 μmol/L)对EPCs数量和功能的影响并无显著差异.上述观察结果提示他汀类药物可增加EPCs的数量,改善EPCs功能.     

Effects of rapamycin on number activity and eNOS of endothelial progenitor cells from peripheral blood

The aim of this investigation is to determine whether rapamycin treatment has any effect on endothelial progenitor cells (EPCs). Total mononuclear cells (MNCs) were isolated from peripheral blood by Ficoll density gradient centrifugation, and then the cells were plated on fibronectin-coated culture dishes. After 7 days in culture, attached cells were stimulated with rapamycin (in a series of final concentrations: 0.1, 1.0, 2.0 and 5.0 g/ml) for 6, 12, 24 and 48 h. EPCs were characterized as adherent cells, double positive for DiLDL uptake and lectin binding by direct fluorescence staining. EPC proliferation and migration were determined using the MTT assay and a modified version of the Boyden chamber assay, respectively. An EPC adhesion assay was performed by replating the cells on fibronectin-coated dishes; adherent cells were then counted. Tube formation activity was assayed by using a tube formation assay kit and endothelial nitric oxide synthase (eNOS) was assayed by Western blot analysis. Incubation of isolated human MNCs with rapamycin decreased the number of EPCs present; rapamycin also decreased EPCs proliferative, migratory, adhesive, tube formation capacity and eNOS production in a concentration- and time-dependent manner. Rapamycin was found to decrease the number, proliferative, migratory, adhesive and tube formation capacities of the EPCs, and also was found to decreases eNOS in the EPCs.     

Comparison of five methods for concentrating progenitor cells in human marrow transplantation

Enrichment of bone marrow (BM) aspirates is an important prerequisite prior to in vitro treatment or cryopreservation. In this regard, we have analyzed the results obtained on 190 BM processed by the following 5 techniques: HES sedimentation with centrifugation; COBE 2991 blood cell processor; Ficoll/hypaque (F/H) gradient centrifugation; Continuous flow cell separator (CS 3000 Fenwal); Semicontinuous blood cell separator (Dideco T 90). Each procedure was evaluated by measuring the recovery of nucleated marrow cells (NC), mononuclear cells (MNC), committed progenitor cells (CFU-GM), the reduction of BM volume and the removal of red blood cells (RBC) and polymorphonuclear cells (PMN). The results of this comparative study show that F/H gradient on a COBE 2991 cell washer provides the most efficient system for purifying a MNC fraction (89% recovery) from unwanted cells (RBC less than 2% and PMN less than 2%) in a very small volume (98% reduction) with a good recovery of CFU-GM (80%).     

匹伐他汀对体外培养人脐静脉血内皮祖细胞数量及功能的影响

目的：通过体外培养人脐静脉血内皮祖细胞（endothelial progenitor cells,EPCs）,观察他汀类新药（匹伐他汀）对EPCs数量及增殖、迁移和粘附功能的影响。方法：采用密度梯度离心法分离培养人脐静脉血单个核细胞,将其接种在包被有人纤维连接蛋白培养板上,培养7 d后,收集贴壁细胞,加入不同浓度匹伐他汀（分别为0.001 μmol/L、0.01 μmol/L、0.1 μmol/L、1.0 μmol/L）培养24 h,用免疫荧光法观察EPCs 吸收FITC-UEA-I 和Dil-acLDL情况对EPCs 进行鉴定,然后分别采用MTT 比色法、改良的Boyden小室、粘附能力测定实验对各实验组测定,来观察匹伐他汀对EPCs 数量及增殖、迁移和粘附功能影响。结果：匹伐他汀组与对照组相比,匹伐他汀显著提高了体外培养EPCs的数量及增殖、迁移与粘附能力（P〈0.05）。匹伐他汀浓度在0.1 μmol/L 时对EPCs影响达到最大。随着药物浓度的继续增大,EPCs的上述功能反呈下降趋势,但1.0 μmol/L 组仍高于对照组。结论：匹伐他汀能增加体外培养EPCs的数量及增殖、迁移和粘附能力,可作为EPCs 培养的一种改良方法,为其更好的应用于临床具有重要的意义。     

Two detergent-insoluble proteins of the human lymphocyte membrane are enriched in an isolated membrane fraction

Human lymphocytes isolated from peripheral blood on Ficoll/Paque density gradients were surface-labelled by 125I/lactoperoxidase or 3H/reductive alkylation and lysed in buffer solutions containing non-ionic or amphoteric detergents (octylphenylpolyoxyethylenes, octylglucoside, cholylamidopropyldimethylammoniopropane sulfonate) under a variety of conditions. The cell lysate was fractionated by sedimentation or by density gradient centrifugation. The large majority of the labelled proteins is solubilized by the detergents. Two proteins of 45 000 and 30 000 molecular weight are the main detergent-insoluble, surface-labelled components. They can be fractionated from detergent lysates of cells in relatively pure form from the other membrane proteins and from nuclear material on density gradients. The same two proteins are specifically enriched in a membrane fraction isolated from a detergent-free cell homogenate by density gradient centrifugation. Cytoskeletal and other intracellular proteins remain associated with these two proteins when fractionated by either of these two independent methods.     

Two detergent-insoluble proteins of the human lymphocyte membrane are enriched in an isolated membrane fraction

Human lymphocytes isolated from peripheral blood on Ficoll/Paque density gradients were surface-labelled by ¹²⁵I/lactoperoxidase or ³H/reductive alkylation and lysed in buffer solutions containing non-ionic or amphoteric detergents (octylphenylpolyoxyethylenes, octylglucoside, cholylamidopropyldimethylammoniopropane sulfonate) under a variety of conditions. The cell lysate was fractionated by sedimentation or by density gradient centrifugation. The large majority of the labelled proteins is solubilized by the detergents. Two proteins of 45 000 and 30 000 molecular weight are the main detergent-insoluble, surface-labelled components. They can be fractionated from detergent lysates of cells in relatively pure form from the other membrane proteins and from nuclear material on density gradients. The same two proteins are specifically enriched in a membrane fraction isolated from a detergent-free cell homogenate by density gradient centrifugation. Cytoskeletal and other intracellular proteins remain associated with these two proteins when fractionated by either of these two independent methods.     

Attachment of marine sponge cells of Hymeniacidon perleve on microcarriers

Toward the development of an in vitro cultivation of marine sponge cells for sustainable production of bioactive metabolites, the attachment characteristics of marine sponge cells of Hymeniacidon perleve on three types of microcarriers, Hillex, Cytodex 3, and glass beads, were studied. Mixed cell population and enriched cell fractions of specific cell types by Ficoll gradient centrifugation (6%/8%/15%/20%) were also assessed. Cell attachment ratio (defined as the ratio of cells attached on microcarrier to the total number of cells in the culture) on glass beads is much higher than that on Cytodex 3 and Hillex for both mixed cell population and cell fraction at Ficoll 15-20% interface. The highest attachment ratio of 41% was obtained for the cell fraction at Ficoll 15-20% interface on glass beads, which was significantly higher than that of a mixed cell population (18%). The attachment kinetics on glass beads indicated that the attachment was completed within 1 h. Cell attachment ratio decreases with increase in cell-to-microcarrier ratio (3-30 cells/bead) and pH (7.6-9.0). The addition of serum and BSA (bovine serum albumin) reduced the cell attachment on glass beads.     

Studies of complement receptors on cytotoxic effector cells in human peripheral blood

The question of whether cells bearing complement receptors (CR) mediate cytotoxicity in vitro against allogeneic Chang liver cell targets was investigated by assessing peripheral blood mononuclear cells (PBMC) from normal humans for cell surface characteristics and cytotoxic capacity before and after depletion of CR+ cells capable of forming rosettes with sheep erythrocytes coated with 19S antibody and mouse complement (EAC) and depletion of Fc receptor-bearing cells capable of forming rosettes with human O+ erythrocytes coated with Ripley antibody (EA-Ripley). PBMC depleted of CR+ cells by density centrifugation contained markedly reduced proportions of phagocytes and sIg + cells and increased proportions of both sIg ?, FcR+ cells as well as cells forming rosettes with sheep erythrocytes (E). PBMC depleted of CR+ cells mediated cytotoxicity to an extent equal to or greater than that mediated by unfractionated PBMC in assays of spontaneous cell-mediated cytotoxicity (SCMC), antibody-dependent cellular cytotoxicity (ADCC), and mitogen-induced cellular cytotoxicity (MICC). Cells harvested from the EAC-rosette enriched pellet mediated cytotoxicity 5- to 10-fold less than unfractionated PBMC; however, the cytotoxic activity of the pellet could not be attributed to CR + effector cells since similar cytotoxic activity was present in cell pellets obtained by density centrifugation of PBMC which had been incubated with E coated with 19S antibody or E alone. PBMC depleted of EA-Ripley rosette-forming cells contained decreased proportions of sIg?, FcR+ cells and increased proportions of CR+ cells; PBMC so depleted contained virtually no SCMC and ADCC effector cell activity. These findings indicate that at least the majority of effector cells which mediate SCMC, ADCC, and MICC do not bear CR.     

Immunophenotype of human lymphocytes after interaction with mesenchymal stromal cells

Human multipotent mesenchymal stromal cells (MMSCs) were cocultured with allogenic blood-born mononuclear cells (MNCs). The MNCs consisted of cells that differed in their maturity or functional state, such as lymphocytes from adult peripheral blood vs. umbilical cord blood (cb) or nonstimulated vs. phytohemagglutinin (PHA)-activated lymphocytes from peripheral blood, respectively. The share of T, B, and natural killer (NK) cells or T cell subsets within the initial MNCs or cbMNCs were within physiological reference range for adult peripheral blood. After coculturing with the MMSCs, the populations of B cells decreased in both MNCs and cbMNCs, whereas the populations of the T and NK cells decreased among cbMNC only (p < 0.05). A decrease in the subset of T-NK cells was observed in the T cells of both MNCs and cbMNCs. In the coculture of MMSCs and PHA-MNCs, we found decrease in the number of CD8⁺ and HLA-DR⁺ cells and an increase in the number of CD25⁺ lymphocytes compared to monocultured PHA-MNCs. Our data show that the interaction with MMSCs did not substantially modify the composition of allogenic lymphocytes independent of their maturation (MNCs vs. cbMNCs) or activation (MNCs vs. PHA-MNCs), and the means were within the physiological limits. Moreover, exposure to the MMSCs did not reduce the viability of lymphocytes and even promoted the survival of cells in case of cbMNCs.     

Efficient isolation and enrichment of mesenchymal stem cells from bone marrow

Background aimsBone marrow (BM) mesenchymal stromal cells (MSC) have been identified as a source of pluripotent stem cells used in clinical practice to regenerate damaged tissues. BM MSC are commonly isolated from BM by density-gradient centrifugation. This process is an open system that increases the risk of sample contamination. It is also time consuming and requires technical expertise that may result in variability regarding cellular recovery. The BD Vacutainer^® Cell Preparation Tube? (CPT) was conceived to separate mononuclear cells from peripheral blood. The main goal of this study was to verify whether MSC could be isolated from BM using the CPT.MethodsBM was harvested, divided into two equal aliquots and processed using either CPT or a Ficoll-Paque? PREMIUM density gradient. Both methods were compared regarding cell recovery, viability, proliferation, differentiation capacities and the presence of MSC progenitors.ResultsSimilar numbers of mononuclear cells were isolated from BM when comparing the two methods under study. No differences were found in terms of phenotypic characterization, viability, kinetics and lineage differentiation potential of MSC derived by CPT or Ficoll. Surprisingly, a fibroblast–colony-forming unit (CFU-F) assay indicated that, with CPT, the number of MSC progenitors was 1.8 times higher compared with the Ficoll gradient separation.ConclusionsThe CPT method is able to isolate MSC efficiently from BM, allowing the enrichment of MSC precursors.     

Cytotoxic activity of normal and Herpesvirus saimiri-transformed nonhuman primate cells

Owl monkey mononuclear cells were separated from peripheral blood by centrifugation on Ficoll gradients, removal of adherent cells, and subsequent separation on discontinuous Percoll gradients. Lymphocytes recovered from the various fractions were tested for cytotoxic reactivity immediately after isolation. Low-density cells, enriched in large granular lymphocytes (LGL), demonstrated cytotoxic activity against the human natural killer-susceptible cell lines MOLT 4 and K562. In addition, IL-2-independent T-cell lines which had been obtained by immortalization with the primate herpesvirus Herpesvirus saimiri showed cytotoxicity, even after prolonged culture in vitro, similar to that demonstrated by fresh LGL. Cytotoxic activity of these lines was regulated by IL-2 in a fashion which appeared to be independent of the growth-promoting effects of this lymphokine. These results indicate a function for IL-2 beyond its role in supporting cellular proliferation. Cytotoxic activity could also be demonstrated in culture fluids from one of these cell lines (70N2). In addition, these results indicate the usefulness of immortalized cell lines (like 70N2) as a potential source for studies of the biochemical characterization and purification of supernatants containing cytotoxic factors.     

Novel automated blood separations validate whole cell biomarkers

Background

Progress in clinical trials in infectious disease, autoimmunity, and cancer is stymied by a dearth of successful whole cell biomarkers for peripheral blood lymphocytes (PBLs). Successful biomarkers could help to track drug effects at early time points in clinical trials to prevent costly trial failures late in development. One major obstacle is the inaccuracy of Ficoll density centrifugation, the decades-old method of separating PBLs from the abundant red blood cells (RBCs) of fresh blood samples.

Methods and Findings

To replace the Ficoll method, we developed and studied a novel blood-based magnetic separation method. The magnetic method strikingly surpassed Ficoll in viability, purity and yield of PBLs. To reduce labor, we developed an automated platform and compared two magnet configurations for cell separations. These more accurate and labor-saving magnet configurations allowed the lymphocytes to be tested in bioassays for rare antigen-specific T cells. The automated method succeeded at identifying 79% of patients with the rare PBLs of interest as compared with Ficoll''s uniform failure. We validated improved upfront blood processing and show accurate detection of rare antigen-specific lymphocytes.

Conclusions

Improving, automating and standardizing lymphocyte detections from whole blood may facilitate development of new cell-based biomarkers for human diseases. Improved upfront blood processes may lead to broad improvements in monitoring early trial outcome measurements in human clinical trials.     

Altered interleukin production during Friend leukemia virus infection

Spleen cells from BALB/c mice, infected 14 to 28 days earlier with Friend leukemia virus (FLV), were shown to be inhibited in their ability to produce interleukin 2 (IL-2) when stimulated with mitogen. Likewise, these spleen cell populations failed to respond following mitogenic stimulation or exogenous addition of recombinant IL-2. By contrast, the FLV-infected spleen cell populations produced normal levels of interleukin 1 (IL-1) and thymocytes from FLV-infected mice responded normally to addition of exogenous IL-1. This suggests that FLV infection selectively affects the ability of spleen cells to produce cytokines. Spleen cell populations enriched for T lymphocytes and depleted of tumor cells by density gradient centrifugation in Ficoll were unable to produce IL-2. This indicates that the failure to detect IL-2 in cells from FLV-infected mice was not due to a dilution of T lymphocytes by tumor cells but was a functional inability to produce IL-2. Furthermore, enriched T lymphocytes from FLV-infected mice failed to respond blastogenically to exogenous IL-2. Additional studies indicate that tumor cells, but not macrophages or T lymphocytes from FLV-infected spleens, suppressed the blastogenic response to mitogens and IL-2 production by normal splenic T lymphocytes.     

不同麻醉方法对胃肠道肿瘤手术病人细胞免疫功能的影响

目的:探讨不同麻醉方法对胃肠道肿瘤患者围术期外周血T细胞亚群以及白细胞介素-2(IL-2)的影响.方法:选择胃肠道肿瘤手术患者40例,随机分为两组.采用单纯全麻者为对照组,采用全麻复合硬膜外麻醉者为治疗组.分别于麻醉前、麻醉后不同时间点抽取静脉血,流式细胞术测定CD4+T及CD8+T细胞亚群数量,ELISA法测定血清IL-2的浓度.结果:麻醉后两组患者的CD4+T细胞、CD4+/CD8+比值和血清IL-2浓度均有所下降,与麻醉前比较差异有统计学意义(P＜0.05),治疗组患者的CD4+T细胞及IL-2下降程度不如对照组患者明显,且恢复较快,两组间差异有统计学意义(P＜0.05).结论:胃肠道肿瘤患者在麻醉手术后其细胞免疫功能受到不同程度的抑制,但复合麻醉较单纯全麻的免疫抑制效应低且恢复较快.     

Optimization of an enrichment process for circulating tumor cells from the blood of head and neck cancer patients through depletion of normal cells

The optimization of a purely negative depletion, enrichment process for circulating tumor cells (CTCs) in the peripheral blood of head and neck cancer patients is presented. The enrichment process uses a red cell lysis step followed by immunomagnetic labeling, and subsequent depletion, of CD45 positive cells. A number of relevant variables are quantified, or attempted to be quantified, which control the performance of the enrichment process. Six different immunomagnetic labeling combinations were evaluated as well as the significant difference in performance with respect to the blood source: buffy coats purchased from the Red Cross, fresh, peripheral blood from normal donors, and fresh peripheral blood from human cancer patients. After optimization, the process is able to reduce the number of normal blood cells in a cancer patient's blood from 4.05 × 10⁹ to 8.04 × 10³ cells/mL and still recover, on average, 2.32 CTC per mL of blood. For all of the cancer patient blood samples tested in which CTC were detected (20 out of 26 patients) the average recovery of CTCs was 21.7 per mL of blood, with a range of 282 to 0.53 CTC. Since the initial number of CTC in a patient's blood is unknown, and most probably varies from patient to patient, the recovery of the CTC is unknown. However, spiking studies of a cancer cell line into normal blood, and subsequent enrichment using the optimized protocol indicated an average recovery of approximately 83%. Unlike a majority of other published studies, this study focused on quantifying as many factors as possible to facilitate both the optimization of the process as well as provide information for current and future performance comparisons. The authors are not aware any other reported study which has achieved the performance reported here (a 5.66 log₁₀) in a purely negative enrichment mode of operation. Such a mode of operation of an enrichment process provides significant flexibility in that it has no bias with respect to what attributes define a CTC; thereby allowing the researcher or clinician to use any maker they choose to define whether the final, enrich product contains CTCs or other cell type relevant to the specific question (i.e., does the CTC have predominately epithelial or mesenchymal characteristics?). Biotechnol. Bioeng. 2009;102: 521–534. © 2008 Wiley Periodicals, Inc.     

Effects of castration and replacement of androgen on the separation of rat ventral prostate cells by Ficoll gradient centrifugation

When regressing or growing (hypertrophic) cells from collagenase-digested ventral prostates were centrifuged on isokinetic Ficoll gradients for 6-8 min, they distributed into four fractions. Because of changes in epithelial cell morphology and density following castration to induce regression and replacement of androgens to cause cell growth, and contrary to results with normal rat ventral prostate, stromal cell fraction 2 was contaminated to a greater extent with regressing epithelial cells, as judged by their morphology and binding of radioactive androgens. However, centrifugation for 3 min increased the purity of epithelial cell fraction 4, although the yield of desired cells was reduced. Most cells from endocrine-manipulated rats were viable, as judged by exclusion of trypan blue and the initial incorporation of 3H-uridine. Cells centrifuged on a similar gradient of Percoll separated by a 'sieving' effect, which inverted the order of cellular fractions and removed red blood cells from fraction 2. Metrizamide offered no advantages, compared with Ficoll or Percoll. Neither physiologic nor pharmacologic amounts of testosterone returned the morphology of isolated epithelial cells to normal. To obtain consistent results with prostates from normal or hormone-manipulated rats, one should take care to select an active preparation of collagenase, avoid the use of very old animals, cool the tissue after it is dissociated, and do not apply undigested clumps of cells or overload the gradient. If attention is paid to these details, populations enriched in viable regressing or growing prostate epithelial or stromal cells can be obtained from hormonally manipulated rats.