Human T lymphocyte phenotypes after bone marrow transplantation. T cells expressing Ia-like antigen

Peripheral blood Ia-positive (Ia+) T cells were enumerated in 52 patients who had received allogeneic or syngeneic bone marrow transplantation for the treatment of acute leukemia or severe aplastic anemia. Twenty-two normal people showed 3 +/- 2% of peripheral blood T cells to be Ia+. During the first 130 days posttransplant, all patient groups showed a moderate elevation in the percentage (mean: 21-26%) of Ia+ T cells, regardless of the type of transplant performed, and regardless of the presence or absence of acute graft-versus-host disease (GVHD). Although there was marked individual variation (range 5-76%), there was a trend towards a decrease in the percentage of Ia+ T cells with increasing time after transplantation. Long-term survivors still showed a small (range 3-20%, mean 10%) but significant elevation in the relative number of Ia+ T cells 1-3.4 years after transplantation, regardless of the presence or absence of chronic GVHD. It is not currently known why Ia+ T cells are found in these patients, but accelerated lymphopoiesis, subclinical infection, and excessive immune stimulation caused by microorganisms or other foreign antigens could be contributing factors.     

Bone marrow-derived mesenchymal stem cells versus bone marrow nucleated cells in the treatment of chondral defects

Purpose  

The aim of this study was to compare bone marrow-derived mesenchymal stem cells (MSCs) with bone marrow nucleated cells (BNCs) as seed cells in the treatment of cartilage defects.     

Separate Ia-like determinants in human lymphocytes and macrophages.

Some human alloantisera cytotoxic for B-lymphocyte preparations lost their reactivity when the number of contaminating monocytes was decreased by treatment with carbonyl iron. Such sera were found to react with the corresponding monocyte preparations isolated by adherence to Petri dishes. Macrophage antibodies were present in 38% of random sera from multiparous women and in 70% of sera from kidney transplant recipients. They could not be absorbed with B-lymphocyte preparations, thus suggesting that determinants expressed in macrophages were not present in B lymphocytes. Macrophages stimulate in mixed lymphocyte culture and participate in immune reactions. It is possible that alloantigens of macrophages, as observed in the present experiments, are products of genes associated with these histocompatibility-controlled functions.     

Monoclonal antibody analysis of canine hemopoietic cells. Role of Ia-like and Thy-1 antigens in bone marrow engraftment

The expression of Ia-like (class II MHC) antigens on canine hemopoietic cells was investigated using a cytotoxic murine monoclonal antibody, WM-2, reactive with dog Ia-like antigens. Another monoclonal antibody, WMD-1, reactive with canine Thy-1 antigen, was used as a positive control. Depletion of Ia+ cells from dog bone marrow by complement-mediated lysis with WM-2 antibody failed to inhibit growth of granulocyte-macrophage progenitors (CFUGM) in vitro, while WMD-1 produced complete inhibition of CFUGM. Lethally irradiated dogs receiving bone marrow autografts depleted of Ia-positive cells ex vivo showed initial engraftment, followed by prolonged pancytopenia, and eventual complete recovery of marrow function in the majority of animals. In contrast, dogs receiving autografts treated with WMD-1 and complement all died of marrow failure. We interpret these results as indicating: (1) that Thy-1 antigen is present on hemopoietic stem cells essential for marrow engraftment; and (2) that the expression of Ia antigens on hemopoietic cells is heterogeneous and related to the level of stem cell maturation. While Ia appears to be present on a stem cell population at an earlier stage than CFUGM, as evidenced by the transient phase of graft failure seen in dogs receiving Ia-depleted marrow, the most primitive stem cell, responsible for long-term engraftment, is effectively Ia-negative.     

Close association between Fc receptor and HLA-D-associated (Ia-like) determinants on human lymphoid cells.

The inhibitory effect of HLA antisera on Fc receptors of human lymphoid FcRFC and K cells was investigated. Antisera recognizing determinants of the HLA-A, -B, and -C series had no effect on FcRFC, while specific inhibition was observed with an antiserum reacting with determinants closely associated to HLA-DW2. This inhibitory effect was also demonstrated by the Fab' fragments. Specific inhibition of K cells was observed with all HLA antisera, but this effect was lost in the Fab' fragments. We concluded that the Fc receptor of FcRFC may be closely associated with products of the HLA-D region. This is analogous to the association between the Fc receptor and the Ia antigens on murine splenic B lymphocytes.     

Xenogeneic bone marrow transplantation: II. Porcine-specific growth factors enhance porcine bone marrow engraftment in an in vitro primate microenvironment

Abstract: Establishment of mixed bone marrow chimerism in pig-to-primate transplantation, as a means of inducing specific immune tolerance, will require that both immune and nonimmune barriers be overcome. As a preliminary step in evaluating nonimmune barriers in this system, we have developed an in vitro model of engraftment in which long-term culture of porcine bone marrow-derived hematopoietic cells is supported on preformed primate bone marrow stromal layers. In the absence of cytokine supplementation, primate stromal cells were unable to support long-term porcine hematopoiesis in these cultures. Supplementation with porcine Steel Factor was required for long-term maintenance of hematopoietic progenitor cell content and total hematopoietic activity. Addition of porcine IL-3, in combination with porcine Steel Factor, increased long-term progenitor cell content and hematopoietic activity on primate stroma to levels comparable to that obtained in cultures on porcine stroma. The combination of porcine GM-CSF and Steel Factor increased progenitor cell content and hematopoietic activity early in the cultures, but had little effect in long-term cultures. The Steel Factor and IL-3 combination was species-specific in its action in these cultures, as the corresponding human cytokines were unable to effectively support long-term porcine hematopoiesis. Likewise, the combination of porcine cytokines had only minimal effects on long-term bone marrow culture of primate CD34+ cells I on primate stroma.     

Concentration of bone marrow total nucleated cells by a point-of-care device provides a high yield and preserves their functional activity

Stem and progenitor cell therapy is a novel strategy to enhance cardiovascular regeneration. Cell isolation procedures are crucial for the functional activity of the administered cellular product. Therefore, new isolation techniques have to be evaluated in comparison to the Ficoll isolation procedure as the current gold standard. Here we prospectively evaluated a novel point-of-care device (Harvest BMAC System) for the concentration of bone marrow total nucleated cells (TNC) in comparison to the Ficoll isolation procedure for bone marrow mononucleated cells (MNC). The yield in total numbers of TNC was 2.4-fold higher for Harvest compared to Ficoll. Despite significant differences in their cellular compositions, the colony-forming capacity was similar for both products. Intriguingly, the migratory capacity was significantly higher for the Harvest TNC (164 +/- 66%; p = 0.007). In a mouse model of hind limb ischemia, the increase in blood flow recovery was similar between Harvest BM-TNC and Ficoll BM-MNC (0.53 +/- 0.20 vs. 0.46 +/- 0.15; p = 0.88). However, adjustment of the injected cell number based on the higher yield of Harvest TNC resulted in a significant better recovery (0.64 +/- 0.16 vs. 0.46 +/- 0.15; p = 0.003). Cells concentrated by the Harvest point-of-care device show similar or greater functional activity compared to Ficoll isolation. However, the greater yield of cells and the wider range of cell types for the Harvest device may translate into an even greater therapeutic effect.     

骨髓基质干细胞在体外向软骨细胞分化

目的观察骨髓基质干细胞(B M SC s)在体外能否分化为软骨细胞。方法利用高密度细胞球培养体系在含转化生长因子-β1(TG F-β1)的培养基中培养B M SC s21d,用免疫组化甲苯胺蓝染色方法分析培养的B M SC s球中蛋白多糖(软骨细胞分泌的主要基质成份)的表达、用免疫组化和R T-P C R方法分析Ⅱ型胶原(软骨细胞特异分泌的主要胶原蛋白)的表达来评估B M SC s是否分化为软骨细胞。结果TG F-β1作用的B M SC s表达了Ⅱ型胶原和蛋白多糖。结论B M SC s在体外特定的培养条件下可分化为软骨细胞,从而可能成为临床上治疗创伤或骨关节炎所致的软骨缺损所需的合适的自体来源的种子细胞。     

Restoration of bone defect and enhancement of bone ingrowth using partially demineralized bone matrix and marrow stromal cells

PURPOSE: This study aimed to investigate the capability of combining marrow stromal cells (MSC) and partially demineralized bone matrix (PDBM) to fill bone defect and enhance bone ingrowth using a canine non-weight-bearing gap model. METHODS: Custom-made implants with 3mm gap between the porous surface and the host bone were used. The implants were inserted into the distal femurs of 25 mongrel dogs and the gaps were randomly assigned to be filled with culture-expanded autologous MSC-loaded PDBM, autograft, fresh-frozen allograft, PDBM alone, or nothing as controls. Histomorphometry using backscattered scanning electron microscopic examination, and mechanical push-out test were performed at 6 months after surgery. RESULTS: Histomorphometry showed that amounts of bone regeneration in the gap and bone ingrowth into the porous-coated surface in the MSC-loaded PDBM-treated group were comparable to those of autograft-treated group and were significantly greater than those of allograft-treated, PDBM-treated, or non-grafted groups. Mechanical test showed the same differences. CONCLUSION: The results of this study showed that combining PDBM and autologous culture-expanded MSC restored bone stock and enhanced bone ingrowth into the porous-coated area in a canine non-weight-bearing gap model. This combination may provide an option for reconstructing bone defect when we perform a cementless revision arthroplasty.     

Prolongation of graft survival in ALS-treated mice by donor-specific bone marrow. Density gradient fractionation of the active bone marrow cells

Antilymphocyte serum (ALS)-treated recipient mice that are infused with donor bone marrow cells have been shown to enjoy prolonged skin graft survival. In the present experiments, discontinuous density gradient centrifugation in Percoll was used to prepare fractions of these cells. Two of four fractions had good graft-prolonging ability. In experiments in which the density of the gradients was varied, we were able to estimate the density of a major portion of the cells active in graft prolongation as being in a range of 1.061 to 1.066 g/ml, and to produce one fraction with superior graft-prolonging activity. This fraction constituted only 10% of the recovered cells, was enriched for small-to-medium lymphocytes, Ia+, Thy-1+, and IgM+ cells, and contained cells bearing a marker known to be present on active cells, Fc gamma R. Additionally, this fraction contained cells capable of suppressing the mixed lymphocyte reaction, although two denser fractions, of poor-to-good graft-prolonging ability, also shared this ability. The effectiveness of this method in bringing about a high-capacity, rapid isolation of cells that can augment graft survival in immunosuppressed recipients makes it well suited for future clinical application.     

淋巴因子激活的骨髓细胞对小鼠同种异体骨髓移植的影响

以致死性剂量照射的成年小鼠为受鼠进行同种异体骨髓移植（Ａｌｌｏ－ＢＭＴ），实验组小鼠观察期间平均存活天数较对照组明显延长（Ｐ＜０．００１），应用肿瘤移植及单向混合淋巴细胞培养（ＭＬＣ）二项指标证实Ａｌｌｏ－ＢＭＴ的部分植活。实验结果表明，淋巴因子激活的骨髓细胞（ＬＡＢＭＣ）可有效预防致死性移植物抗宿主病（ＧＶＨＤ），且不影响供髓植活。     

Early events in natural resistance to bone marrow transplantation. Use of radiolabeled bone marrow cells

Natural resistance against the proliferation of splenic colony-forming units (CFU-S) is seen in certain combinations of bone marrow donors and irradiated hosts. In order to examine the early events following bone marrow transplantation and to determine whether genetically determined CFU-S repression is due to elimination of the transplanted cells from the spleen or to inhibition of their proliferation, we labeled proliferating cells in freshly isolated bone marrow or long-term bone marrow cultures (LTBMC) with radioactive I-iododeoxyuridine prior to injection. A heterogeneous mixture of cells was labeled in both freshly isolated marrow and LTBMC; CFU-S precursors were among the cells labeled as indicated by reduction of CFU-S numbers in the radiolabeled cell population. Radiolabeled cells from C57BL/6J, DBA/2J, and B6D2F1 mice were injected into syngeneic, semisyngeneic, and allogeneic irradiated mice that were killed at various times after injection to determine the amount of radioactivity remaining and the organ distribution of the labeled cells; additional mice were killed 7-8 days later to count CFU-S. Retention of label in the spleen was predictive of subsequent CFU-S numbers, suggesting that killing or elimination of the transplanted cells from the spleen is the cause of CFU-S depression in resistant animals. Further genetic analysis of the survival of the radiolabeled cells in the spleen indicated that mismatching of H-2 homozygous donor cells with the host at H-2D was a prerequisite for resistance and that H-2 heterozygous cells were not resisted in spite of H-2 mismatching. Although natural killer (NK) cell-deficient beige mice were able to resist H-2-nonidentical bone marrow cells, pretreatment of the host with anti-asialo GM-1 antibodies completely abrogated natural resistance as assessed by splenic survival or radiolabeled cells. The findings that splenic survival or radiolabeled bone marrow cells reflects the immunogenetic specificity of CFU-S repression and that abrogation of CFU-S repression increases the splenic survival of the labeled cells strengthen the postulate that repression of CFU-S proliferation involves events occurring within the first 24 hr after injection.     

应用骨髓法培养树突状细胞的研究

目的探讨培养树突状细胞(DC)的最佳方法和合理的培养时间。方法取大鼠的骨髓细胞分别加入4种细胞因子重组大鼠粒细胞巨噬细胞集落刺激因子(rrGMCSF)5μg/L,重组大鼠白细胞介素4(rrIL4)5μg/L,重组大鼠肿瘤坏死因子α(rrTNFα)10μg/L,重组大鼠γ干扰素(rrγIFN)20μg/L培养2周,并用PE标记的抗大鼠CD86单克隆抗体检测它的成熟度。结果从第7天开始细胞周围开始逐渐伸出突起,第13天以后突起5～6支左右,且长度逐渐缩短,成熟的树突状细胞伸出长短不等的突起,类似神经细胞的树突。60只大鼠培养所得的树突状细胞平均为(1.18±0.21)×107第7、11、13、15天的CD86单抗的阳性率分别为30%、80%、92%、94%,随着时间的延长,它的阳性率不断增加,尤以第1周到第2周之间增长的特别明显,但2周以后,树突状细胞的成熟度无明显提高。结论应用骨髓法来培养树突状细胞加入细胞因子rrGMCSF、rrIL-4、rrTNF-α、rr-γ-IFN培养2周,可得到成熟的树突状细胞。     

Chimerism induction in vascularized bone marrow transplants augmented with bone marrow cells

Composite tissue allografts (CTAs) are currently accepted in the clinic; however, long-term immunosuppression is still needed for allograft survival. The presence of donor-specific chimerism may induce tolerance. Thirty-six vascularized bone marrow transplantation (VBMT) allotransplantation were performed across MHC barrier under short-term protocol of 7-day alphabeta-TCRmAb and Cyclosporin A therapy to determine the efficacy of VBMT alone and VBMT augmented with donor bone marrow transplantation (BMT) in chimerism induction. Flow cytometry analysis revealed that VBMT supported with donor BMT directly into the bone resulted in chimerism augmentation and maintenance compared to VBMT. In vivo and in vitro tolerance testing showed prolonged survival of donor skin graft up to 35 days and moderate reactivity in MLR assay that suggests only tolerance induction. Transplantation of vascularized bone without chronic immunosuppression provides a substantial source of bone marrow cells, leading to the development of stable donor-specific chimerism.     

腺病毒介导人骨形态蛋白-7基因感染大鼠髓腔细胞的实验研究

目的 :观察已构建好的腺病毒介导的骨形态蛋白 7基因感染大鼠髓腔内细胞的情况 ,为腺病毒介导BMP 7的进一步基因治疗提供可靠的实验基础。材料和方法 :从人骨肉瘤细胞株U 2OS中获得hBMP 7的cDNA片段 ,插入穿梭质粒后在大肠杆菌内与腺病毒实现同源重组 ,阳性克隆转染 2 93细胞 ,扩增纯化得到大量病毒后注入大鼠椎体髓腔中 ,用冲洗髓腔的方法和流式细胞仪分析来观察注射椎体和上位椎体髓腔内细胞感染腺病毒BMP 7的情况 ,并观察病毒感染的时限。结果 :经体外检测能高效表达活性BMF 7的构建好的AdBMP 7注入椎体髓腔后 ,髓腔冲洗液的荧光显微镜观察 ,术后 1 2d和 2 4d都有感染了带有荧光蛋白标记的髓腔内细胞 ,而且在注射椎体的上位椎体中也出现了感染病毒的细胞。结论 :腺病毒介导的BMP -7基因能够在体内感染髓腔细胞并分泌活性的BMP -7,可以成为基因治疗的有效手段。     

骨髓CD34+干细胞与单核细胞应用于组织工程小血管内皮化的比较

目的 探讨骨髓CD34+干细胞与骨髓单核细胞(MNCs)应用于组织工程小血管内皮化的效果,并作比较.方法 采集犬骨髓,经免疫磁珠分离出CD34+细胞,内皮细胞生长因子(VEGF)诱导分化为内皮细胞并扩增,行细胞免疫荧光、免疫组织化学和体外成血管实验鉴定;将培养后的细胞和未经分离的MNCs分别种植于人工小血管支架,扫描电镜观察,比较两组组织工程小血管的内皮化.结果 经流式细胞仪测定,分离后的细胞中CD34+细胞含量为(78.46±6.37)％.CD34+细胞培养2周后细胞基本铺满培养瓶底面,细胞呈“铺路石”状排列,CD31和Ⅷ因子免疫细胞化学染色均为阳性,体外成血管实验显示6h后CD34+细胞组出现较多毛细血管样网状结构.CD34+细胞组人工血管内膜化面积为(68.4±2.3)％,明显高于MNCs组人工血管内膜化面积(41.3±3.4)％,差异有统计学意义(P＜0.01).结论 通过免疫磁珠方法可分离得到高纯度的骨髓CD34+细胞,经体外培养VEGF诱导后可定向分化为内皮细胞,种植于人工血管内表面,较MNCs组内皮化效果理想.