Nonadherent Mononuclear Cells Research Articles

Low Intensity Vibration Treatment Reduces Myeloma Cell-Induced Osteoclast Formation By Inhibiting IL-6 and GFI-1 Production By MM Cells

Multiple myeloma (MM) bone disease is characterized by increased osteoclast-mediated resorption of bone adjacent to tumor growth. Fusion and activation of osteoclasts (OC), indicated by elevated tartrate-resistant acid phosphatase (TRAP) production, are induced by a myriad of inflammatory factors; e.g. TGF-β, growth factor independent 1 transcription factor (GFI-1), RANKL, and IL-6 that are produced by myeloma cells and cells in the marrow microenvironment. Current therapies reduce tumor burden and block osteoclast formation and activity, thereby decreasing bone destruction. However, MM bones rarely heal. While the anabolic effects of exercise on healthy bone are well-documented, patients with compromised skeletal tissue, such as in MM, may not be able to participate in regimented exercise for fear of developing a fracture. Low intensity vibrations (LIV) that deliver subtle mechanical signals, on the order of those induced by fast-twitch muscle fibers on bone, can enhance mesenchymal stem cell differentiation towards osteoblasts. LIV also significantly preserves trabecular bone while reducing tumor burden in femora of mice harboring U266 MM cells. We hypothesize that LIV is both anti-resorptive and anabolic, through differential effects on MM cells and bone cells. To test this hypothesis, we used a vertically oscillating, vibratory platform that delivered mechanical signals (<1 x Earth's gravitational acceleration; where 1g=9.8m/s2) to culture plates.5TGM1 murine MM cells (5x105 cells/well) were cultured in RPMI with 10% FCS and subjected to LIV or Sham-LIV. Each 6-well plate received either LIV (frequency=90Hertz, acceleration=0.3g) or Sham-LIV (SH; unpowered, static platform) twice per day for 20min per treatment for 48hrs. MM cell lysates were then collected using RIPA buffer. IL-6, GFI-1, and RANKL levels were determined via Western Blot using specific monoclonal antibodies. GAPDH was used as the loading control. Conditioned media (CM) were isolated from SH- and LIV-treated MM cultures. Purified primary murine OC precursors (non-adherent marrow mononuclear cells) were expanded with 10ng/mL of MCSF for 3 days and then these cells were isolated by trypsinization and replated in 12-well plates at a density of 5x105 cells/well in α-MEM, 10% FCS, and 30% v/v CM. All cultures were then incubated for 36hrs. OC number and morphology were confirmed via TRAP staining (counterstained with hematoxylin) of the cultures. TRAP+ OC's containing at least three nuclei were quantified in the cultures by microscopy.Expression levels of IL-6 and GFI-1 were 53% (p<0.01) and 50% (p<0.02) lower, respectively, in lysates from LIV-exposed 5TGM1 cells as compared to those that were SH-treated. Expression of RANKL was not significantly different between these groups. TRAP+ OC's were 61% (p<0.005) lower in LIV-treated cultures compared with SH cultures. The morphology of OC's exposed to LIV-conditioned media from MM cultures was distinct from control cultures, with fewer filopodia than OC's in cultures treated with SH-conditioned media. Based on these data we then examined the direct effect of LIV-treatment on committed OC-precursors treated with RANKL (50ng/mL) to induce formation of mature OC's. After 48hrs of LIV-treatment, committed OC-precursors had 36% (p<0.0001) fewer nuclei per OC than in SH-treated cultures. The cultures of committed OC-precursors directly treated with LIV had fewer filopodia in comparison to SH-treated cultures upon examination of OC morphology.These findings suggest that mechanical signals in the form of LIV may influence the secretion of IL-6 and GFI-1 by myeloma cells, which, in turn, can decrease the capacity of MM cells to induce OC formation. The morphology of OC's and expression of TRAP by OC's exposed to LIV further suggest a distinct mechanosensitive effect on osteoclast formation and fusion that may impact their bone resorbing capacity. Thus, LIV has a significant effect on the capacity of MM cells to secrete inflammatory cytokines as well as directly affect OC formation. These results further suggest that low intensity vibrations may be a useful, non-invasive approach for treating myeloma bone disease. DisclosuresRoodman:Amgen Denosumab Trial: Membership on an entity's Board of Directors or advisory committees.

Cardiac glycosides cause cytotoxicity in human macrophages and ameliorate white adipose tissue homeostasis.

Cardiac glycosides inhibit Na+ /K+ -ATPase and are used to treat heart failure and arrhythmias. They can induce inflammasome activation and pyroptosis in macrophages, suggesting cytotoxicity, which remains to be elucidated in human tissues. To determine the cell-type specificity of this cytotoxicity, we used human monocyte-derived macrophages and non-adherent peripheral blood cells from healthy donors, plus omental white adipose tissue, stromal vascular fraction-derived pre-adipocytes and adipocytes from obese patients undergoing bariatric surgery. All these cells/tissues were treated with nanomolar concentrations of ouabain (50, 100, 500 nM) to investigate the level of cytotoxicity and the mechanisms leading to cell death. In white adipose tissue, we investigated ouabain-mediated cytotoxicity by measuring insulin sensitivity, adipose tissue function and extracellular matrix deposition ex vivo. Ouabain induced cell death through pyroptosis and apoptosis, and was more effective in monocyte-derived macrophages compared to non-adherent peripheral blood mononuclear cell populations. This cytotoxicity is dependent on K+ flux, as ouabain causes intracellular depletion of K+ and accumulation of Na+ and Ca2+ . Consistently, the cell death caused by these ion imbalances can be rescued by addition of potassium chloride to human monocyte-derived macrophages. Remarkably, when white adipose tissue explants from obese patients are cultured with nanomolar concentrations of ouabain, this causes depletion of macrophages, down-regulation of type VI collagen levels and amelioration of insulin sensitivity ex vivo. The use of nanomolar concentration of cardiac glycosides could be an attractive therapeutic treatment for metabolic syndrome, characterized by pathogenic infiltration and activation of macrophages. This article is part of a themed issue on Inflammation, Repair and Ageing. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v179.9/issuetoc.

Amplification of Cord Blood-Derived Cytotoxic T Lymphocytes using HL-60 cell Derived Exosomes

IntroductionDendritic cell (DCs) based cytotoxic T lymphocytes (CTLs) are commonly used in immunotherapy due to their specificity. The selection of appropriate cell origin and tumor antigen is the key point. The objective was to culture DCs and CTLs simultaneously from cord blood, and deliver antigen information using tumor derived exosomes.Material and methodsExosomes were collected from the human promyelocytic leukemia cell line HL-60 using ultracentrifugation. Prepared DCs from adherent cord blood mononuclear cells (MNCs) using SCF, GM-CSF, and IN-4. TNF-α and microRNA removed tumor-exosome were used to induce DCs maturation. DCs matured in the presence of HL-60 cell membrane protein extract or no antigen were set as control. CTLs was cultured from non-adherent MNCs by adding IFN-γ, IL-15, SCF, FLT-3L, anti-CD3, anti-CD28 and IL-2. The CTLs were analyzed by flow cytometry, cytotoxicity experiments and ELISA.ResultsDCs can be obtained from cord blood and express costimulatory molecules. After 15 days, the total number of the cells expanded 26.3 times, and more than 82% of the cells expressed CD3+CD8+ in the most amplified HL-60-Ex-DCs-CTL group. These CD3+CD8+ T cells generated by HL-60-Ex-DCs displayed specific cytotoxicity towards HL-60 and low lethality towards unrelated BALL-1 cells. ELISA results showed that the expressions of TNF-α and IFN-γ in HL-60-Ex-DCs or HL-60mPr-DCs activated CTLs were upregulated compared with the control group.ConclusionsCord blood CTLs generated by HL-60 derived exosome activated DCs displayed specific cytotoxicity towards HL-60 promyelocytic leukemia cells. Therefore cord blood and tumor derived exosomes provided a good source for adoptive immunotherapy.

A 3D construct based on mesenchymal stromal cells, collagen microspheres and plasma clot supports the survival, proliferation and differentiation of hematopoietic cells in vivo.

The hematopoietic niche is a specialized microenvironment that supports the survival, proliferation and differentiation of hematopoietic stem progenitor cells (HSPCs). Three-dimensional (3D) models mimicking hematopoiesis might allow in vitro and in vivo studies of the hematopoietic (HP) process. Here, we investigate the capacity of a 3D construct based on non-adherent murine bone marrow mononuclear cells (NA-BMMNCs), mesenchymal stromal cells (MSCs) and collagen microspheres (CMs), all embedded into plasma clot (PC) to support in vitro and in vivo hematopoiesis. Confocal analysis of the 3D hematopoietic construct (3D-HPC), cultured for 24h, showed MSC lining the CM and the NA-BMMNCs closely associated with MSC. In vivo hematopoiesis was examined in 3D-HPC subcutaneously implanted in mice and harvested at different intervals. Hematopoiesis in the 3D-HPC was evaluated by histology, cell morphology, flow cytometry, confocal microscopy and hematopoietic colony formation assay. 3D-HPC implants were integrated and vascularized in the host tissue, after 3months of implantation. Histological studies showed the presence of hematopoietic tissue with the presence of mature blood cells. Cells from 3D-HPC showed viability greater than 90%, expressed HSPCs markers, and formed hematopoietic colonies, in vitro. Confocal microscopy studies showed that MSCs adhered to the CM and NA-BMMNCs were scattered across the 3D-HPC area and in close association with MSC. In conclusion, the 3D-HPC mimics a hematopoietic niche supporting the survival, proliferation and differentiation of HSPCs, in vivo. 3D-HPC may allow evaluation of regulatory mechanisms involved in hematopoiesis.

Pancreatic beta cells persistently infected with coxsackievirus B4 are targets of NK cell-mediated cytolytic activity.

It has been suggested that the persistence of coxsackieviruses-B (CV-B) in pancreatic beta cells plays a role in the pathogenesis of type 1 diabetes (T1D). Yet, immunological effectors, especially natural killer (NK) cells, are supposed to clear virus-infected cells. Therefore, an evaluation of the response of NK cells to pancreatic beta cells persistently infected with CV-B4 was conducted. A persistent CV-B4 infection was established in 1.1B4 pancreatic beta cells. Infectious particles were found in supernatants throughout the culture period. The proportion of cells containing viral protein VP1 was low (< 5%), although a large proportion of cells harbored viral RNA (around 50%), whilst cell viability was preserved. HLA class I cell surface expression was downregulated in persistently infected cultures, but HLA class I mRNA levels were unchanged in comparison with mock-infected cells. The cytolytic activities of IL-2-activated non-adherent peripheral blood mononuclear cells (PBMCs) and of NK cells were higher towards persistently infected cells than towards mock-infected cells, as assessed by an LDH release assay. Impaired cytolytic activity of IL-2-activated non-adherent PBMCs from patients with T1D towards infected beta cells was observed. In conclusion, pancreatic beta cells persistently infected with CV-B4 can be lysed by NK cells, implying that impaired cytolytic activity of these effector cells may play a role in the persistence of CV-B in the host and thus in the viral pathogenesis of T1D.

Vaccine-Mediated Mechanisms Controlling Replication of Francisella tularensis in Human Peripheral Blood Mononuclear Cells Using a Co-culture System.

Cell-mediated immunity (CMI) is normally required for efficient protection against intracellular infections, however, identification of correlates is challenging and they are generally lacking. Francisella tularensis is a highly virulent, facultative intracellular bacterium and CMI is critically required for protection against the pathogen, but how this is effectuated in humans is poorly understood. To understand the protective mechanisms, we established an in vitro co-culture assay to identify how control of infection of F. tularensis is accomplished by human cells and hypothesized that the model will mimic in vivo immune mechanisms. Non-adherent peripheral blood mononuclear cells (PBMCs) were expanded with antigen and added to cultures with adherent PBMC infected with the human vaccine strain, LVS, or the highly virulent SCHU S4 strain. Intracellular numbers of F. tularensis was followed for 72 h and secreted and intracellular cytokines were analyzed. Addition of PBMC expanded from naïve individuals, i.e., those with no record of immunization to F. tularensis, generally resulted in little or no control of intracellular bacterial growth, whereas addition of PBMC from a majority of F. tularensis-immune individuals executed static and sometimes cidal effects on intracellular bacteria. Regardless of infecting strain, statistical differences between the two groups were significant, P < 0.05. Secretion of 11 cytokines was analyzed after 72 h of infection and significant differences with regard to secretion of IFN-γ, TNF, and MIP-1β was observed between immune and naïve individuals for LVS-infected cultures. Also, in LVS-infected cultures, CD4 T cells from vaccinees, but not CD8 T cells, showed significantly higher expression of IFN-γ, MIP-1β, TNF, and CD107a than cells from naïve individuals. The co-culture system appears to identify correlates of immunity that are relevant for the understanding of mechanisms of the protective host immunity to F. tularensis.

Human Bronchial Epithelial Cell-derived Factors from Severe Asthmatic Subjects Stimulate Eosinophil Differentiation.

Activated bronchial epithelial cells (BEC) release various alarmins, including thymic stromal lymphopoietin (TSLP), that drive type 2 inflammation. We hypothesize that BEC-derived factors promote in situ eosinophil differentiation and maturation, a process that is driven by an IL-5-rich microenvironment in asthmatic airways. To assess the eosinophilopoietic potential of epithelial-derived factors, eosinophil/basophil colony forming units (Eo/B-CFU) were enumerated in 14-day methylcellulose cultures of blood-derived nonadherent mononuclear cells incubated with BEC supernatants (BECSN) from healthy nonatopic controls (n = 8), mild atopic asthmatics (n = 9), and severe asthmatics (n = 5). Receptor-blocking antibodies were used to evaluate the contribution of alarmins. Modulation of the mRNA expression of transcription factors that are crucial for eosinophil differentiation was evaluated. BECSN stimulated the clonogenic expansion of eosinophil progenitors in vitro. In the presence of IL-5, Eo/B-CFU numbers were significantly greater in cocultures of BESCN from severe asthmatics compared with other groups. This was attenuated in the presence of a TSLP (but not an IL-33) receptor-blocking antibody. Recombinant human TSLP (optimal at 100 pg/ml) stimulated Eo/B-CFU growth, which was significantly enhanced in the presence of IL-5 (1 ng/ml). Overnight culture of CD34+ cells with IL-5 and TSLP synergistically increased GATA-binding factor 2 and CCAAT/enhancer-binding protein α mRNA expression. The eosinophilopoietic potential of factors derived from BEC is increased in severe asthma. Our data suggest that TSLP is a key alarmin that is produced by BECs and promotes in situ eosinophilopoiesis in a type 2-rich microenvironment.

Model acupuncture point: Bone marrow-derived stromal stem cells are moved by a weak electromagnetic field.

AIMTo show the existence of a structural formative role of magnetic fields (MFs) with respect to biological objects by using our proposed model of an acupoint.METHODSWe introduced a magnetised 10-100 μT metal rod (needle) into culture dishes with a negatively charged working surface and observed during 24 h how cells were arranged by MFs and by electrical fields (EFs) when attached. Rat and human bone marrow-derived stromal stem cells (rBMSCs and hBMSCs), human nonadherent mononuclear blood cells, NCTCs and A172 cells, and Escherichia coli (E. coli) were evaluated. The dish containing BMSCs was defined as the model of an acupoint. rBMSCs proliferative activity affected by the needle was investigated. For investigating electromagnetic field structures, we used the gas discharge visualisation (GDV) method.RESULTSDuring 24 h of incubation in 50-mm culture dishes, BMSCs or the nonadherent cells accumulated into a central heap in each dish. BMSCs formed a torus (central ring) with an inner diameter of approximately 10 mm only upon the introduction of the needle in the centre of the dish. The cells did not show these effects in 35- or 90-mm culture dishes or hydrophobic dishes or rectangular cuvettes. NCTCs and A172 cells showed unstable the effects and only up to two weeks after thawing. Moreover, we observed that the appearance of these effects depended on the season. In winter, BMSCs showed no the effects. GDV experiments revealed that the resonant annular illumination gradually formed from 10 to 18-20 s in polar solutions with and without cell suspension of BMSCs, NCTCs and E. coli when using circular 50-mm dishes, stimulation at 115 V and switching of the electrode poles at 1 kHz. All these data demonstrate the resonant nature of the central ring. Significant influence of MFs on the rBMSC proliferation rate was not observed.CONCLUSIONBMSCs can be moved by MFs when in the presence of a constant EF and MF, when the cells are in the responsive functional state, and when there is a resonant relationship between them.

Isolation and characterization of mesenchymal progenitors derived from the bone marrow of goats native from northeastern Brazil.

To characterize bone marrow progenitors cells grown in vitro, using native goats from northeastern Brazil as animal model. Ten northeastern Brazil native goats of both genders were used from the Piauí Federal University Agricultural Science Center's (UFPI) - Goat Farming Sector. Bone marrow aspirates where taken from the tibial ridge and seeded on culture plates for isolation, expansion and Flow Cytometry (expression markers - Oct-3/4, PCNA, Ck-Pan, Vimentina, Nanog). Progenitor cells showed colonies characterized by the presence of cell pellets with fibroblastoid morphology. Cell confluence was taken after 14 days culture and the non-adherent mononuclear cell progressive reduction. After the first passage, 94.36% cell viability was observed, starting from 4.6 x 106 cell/mL initially seeded. Cells that went through flow cytometry showed positive expression for Oct-3/4, PCNA, Ck-Pan, Vimentina, and Nanog. Bone marrow progenitor isolated of native goats from northeastern Brazil showed expression markers also seen in embryonic stem cells (Oct-3/4, Nanog), markers of cell proliferation (PCNA) and markers for mesenchymal cells (Vimentina and Ck-pan), which associated to morphological and culture growth features, suggest the existence of a mesenchymal stem cell (MSC) population in the goat bone marrow stromal cells studied.

Evaluation of peroxisome proliferator‐activated receptor agonists on interleukin‐5‐induced eosinophil differentiation

Peroxisome proliferator-activated receptor (PPAR) agonists have been suggested as novel therapeutics for the treatment of inflammatory lung disease, such as allergic asthma. Treatment with PPAR agonists has been shown to inhibit airway eosinophilia in murine models of allergic asthma, which can occur through several mechanisms including attenuated generation of chemoattractants (e.g. eotaxin) and decreased eosinophil migrational responses. In addition, studies report that PPAR agonists can inhibit the differentiation of several cell types. To date, no studies have examined the effects of PPAR agonists on interleukin-5 (IL-5) -induced eosinophil differentiation from haemopoietic progenitor cells. Non-adherent mononuclear cells or CD34(+) cells isolated from the peripheral blood of allergic subjects were grown for 2weeks in Methocult(®) cultures with IL-5 (10ng/ml) and IL-3 (25ng/ml) in the presence of 1-1000nm PPARα agonist (GW9578), PPARβ/δ agonist (GW501516), PPARγ agonist (rosiglitazone) or diluent. The number of eosinophil/basophil colony-forming units (Eo/B CFU) was quantified by light microscopy. The signalling mechanism involved was assessed by phosphoflow. Blood-extracted CD34(+) cells cultured with IL-5 or IL-5+IL-3 formed Eo/B CFU, which were significantly inhibited by rosiglitazone (100nm, P<0·01) but not GW9578 or GW501516. In addition, rosglitazone significantly inhibited IL-5-induced phosphorylation of extracellular signal-regulated kinase 1/2. We observed an inhibitory effect of rosiglitazone on eosinophil differentiation in vitro, mediated by attenuation of the extracellular signal-regulated kinase 1/2 signalling pathway. These findings indicate that the PPARγ agonist can attenuate tissue eosinophilia by interfering with local differentiative responses.

Mechanism of activation of natural killer and CD8 T cells by interleukin 15 in the prostate cancer microenvironment

BackgroundThe prostate cancer microenvironment profoundly inhibits effector immune-cell activity. We have shown that interleukin (IL) 15, unlike other cytokines proposed for anti-tumour immunotherapy such as IL12 and IL21, can increase natural killer (NK) cell and CD8 T-cell activity within the prostate cancer microenvironment. To investigate mechanisms of this activation, we studied the effects of IL15 on inhibitory and activatory receptors on NK cells and their corresponding ligands on prostate cancer cells. NK receptors known as killer-Ig-like receptors (KIRs) have a crucial role in NK-mediated killing of tumour cells. NK-receptor ligands on tumour cells can attenuate NK activity by binding their corresponding inhibitory receptors. Conversely, increased HLA-related ligand expression can increase the recognition and killing of tumour cells by T cells. MethodsThe prostate cancer cell-lines PC3 and LNCaP were incubated with non-adherent peripheral blood mononuclear cells (PBMCs) at effector-to-target ratios of 8:1 and cytokines IL2 or IL15. After 1 week, NK cells in the co-cultures were stained with antibodies to inhibitory KIRs (KIR2DL1, KIR2DL2, KIR3DL1) and activatory KIRs (NKp44, NKG2D, NKp46, DNAM1). Tumour cells in the co-cultures were stained with antibodies to inhibitory NK-receptor ligands HLA-class1-Bw4 and HLA-G, and activatory receptor ligands Nectin-2, and MICA/B. Antibody to HLA-ABC was also used. Staining was followed by flow cytometric analysis. Groups were compared with one-way ANOVA and post-hoc Newman-Keuls (five repeated experiments). FindingsIL15, but not IL2, inhibited expression of KIR2DL1 and KIR3DL1 by up to 50% (p<0·001) on NK cells in PBMC-prostate cancer cell co-cultures. NKG2D was increased up to 40% (p<0·001) in these cells with IL15 but not IL2. On tumour cells, IL15 decreased HLA-Class-1-Bw4 and HLA-G by 60% (p<0·001) and 75% (p<0·001), respectively. No significant effects were seen on the activatory-ligands whereas HLA-ABC expression was increased by over 65% (p<0·001). InterpretationOne mechanism by which IL15 increases prostate cancer killing by NK cells in PBMC-prosate cancer co-cultures is through upregulating activatory NKG2D and decreasing inhibitory KIR2DL1 and KIR3DL1 receptors. In addition, inhibitory ligands on prostate cancer cells are downregulated, suggesting strong shifts towards NK activation versus inhibition in the co-cultures. Increased HLA-ABC also favours stronger cytotoxic-T-cell recognition. FundingHeathside Trust, UK Medical Research Council, National Institute for Health Research, Prostate cancer UK. The research was funded and supported by the National Institute for Health Research (NIHR) Biomedical Research Centre based at Guy's and St Thomas' NHS Foundation Trust and King's College London.

Microgravity control of autophagy modulates osteoclastogenesis

Evidence indicates that astronauts experience significant bone loss during space mission. Recently, we used the NASA developed rotary cell culture system (RCCS) to simulate microgravity (μXg) conditions and demonstrated increased osteoclastogenesis in mouse bone marrow cultures. Autophagy is a cellular recycling process of nutrients. Therefore, we hypothesize that μXg control of autophagy modulates osteoclastogenesis. Real-time PCR analysis of total RNA isolated from mouse bone marrow derived non-adherent cells subjected to modeled μXg showed a significant increase in autophagic marker Atg5, LC3 and Atg16L mRNA expression compared to ground based control (Xg) cultures. Western blot analysis of total cell lysates identified an 8.0-fold and 7.0-fold increase in the Atg5 and LC3-II expression, respectively. Confocal microscopy demonstrated an increased autophagosome formation in μXg subjected RAW 264.7 preosteoclast cells. RT2 profiler PCR array screening for autophagy related genes identified that μXg upregulates intracellular signaling molecules associated with autophagy, autophagosome components and inflammatory cytokines/growth factors which coregulate autophagy in RAW 264.7 preosteoclast cells. Autophagy inhibitor, 3-methyladenine (3-MA) treatment of mouse bone marrow derived non-adherent mononuclear cells showed a significant decrease in μXg induced Atg5 and LC3 mRNA expression in the presence or absence of RANK ligand (RANKL) stimulation. Furthermore, RANKL treatment significantly increased (8-fold) p-CREB transcription factor levels under μXg as compared to Xg cultures and 3-MA inhibited RANKL increased p-CREB expression in these cells. Also, 3-MA suppresses μXg elevated osteoclast differentiation in mouse bone marrow cultures. Thus, our results suggest that μXg induced autophagy plays an important role in enhanced osteoclast differentiation and could be a potential therapeutic target to prevent bone loss in astronauts during space flight missions.

Hematopoietic progenitor constituents and adherent cell progenitor morphology isolated from black‐rumped agouti (Dasyprocta prymnolopha, Wagler 1831) bone marrow

Stem cells are present in the adult tissues of most diverse species. Bone marrow is recognized to be the most exploited site to obtain stem cells and cell progenitors. The objective of the present study was to characterize hematopoietic progenitor (HP) morphology and analyze the performance of adherent cell progenitors (ACPs) cultivated in vitro from black-rumped agouti bone marrow (Dasyprocta prymnolopha). Bone marrow aspirates were obtained from tibia crest and used to prepare histological slides and identify cell morphology. Cells were also scattered on culture plates for later isolation, expansion, and quantification. Smears obtained from bone marrow demonstrated HPs at different stages of maturity. In culture, these cells showed fibroblastoid morphology and a strong tendency to form colonies, demonstrated by the presence of cell aggregates, cytoplasmic elongations lying side by side. An 80% cell confluence was observed at 18 days in culture and progressive reduction in the percentage of nonadherent mononuclear cells. After eight passes, a mean cell viability of 96.07% was observed, from a pool of 1.6 × 10(7) cells (ACP). Thirteen 25-cm(2) culture bottles were trypsinized, resuspended in freezing medium, stored in 14 criotubes at a concentration of 1 × 10(6) cells per milliliter, and placed in liquid nitrogen at -196°C. Agouti bone marrow demonstrated high plasticity, moreover different HP lines, and a population of adherent cells demonstrated morphology similar to mesenchymal stem cells in culture.

Chronic Myelogenous Leukemia Cells Contribute to the Stromal Myofibroblasts in Leukemic NOD/SCID MouseIn Vivo

We recently reported that chronic myelogenous leukemia (CML) cells converted into myofibroblasts to create a microenvironment for proliferation of CML cells in vitro. To analyze a biological contribution of CML-derived myofibroblasts in vivo, we observed the characters of leukemic nonobese diabetes/severe combined immunodeficiency (NOD/SCID) mouse. Bone marrow nonadherent mononuclear cells as well as human CD45-positive cells obtained from CML patients were injected to the irradiated NOD/SCID mice. When the chimeric BCR-ABL transcript was demonstrated in blood, human CML cells were detected in NOD/SCID murine bone marrow. And CML-derived myofibroblasts composed with the bone marrow-stroma, which produced significant amounts of human vascular endothelial growth factor A. When the parental CML cells were cultured with myofibroblasts separated from CML cell-engrafted NOD/SCID murine bone marrow, CML cells proliferated significantly. These observations indicate that CML cells make an adequate microenvironment for their own proliferation in vivo.

Vascular endothelial growth factor-C and its receptor type-3 expressed in acute lymphocytic leukemia cases with t(1;19)

The vascular endothelial growth factor (VEGF)-C system was analyzed in two cases of acute lymphocytic leukemia (ALL) with TCF3/PBX1 fusion to determine whether the VEGF-C system influences the growth of these ALL blasts. Bone marrow non-adherent mononuclear cells were prepared from the patients, and expressions of VEGFs and VEGF receptors (VEGFRs) were analyzed based on RNA and protein levels. Cell proliferation was also assayed with or without neutralizing antibodies to VEGFs. The patients' leukemic blasts expressed a significant amount of VEGF-C and VEGFR type-3. When anti-VEGF-C antibody was added to the blast cell cultures, cell proliferation was suppressed. These observations indicate that, in our ALL cases with TCF3/PBX1 fusion, VEGF-C autocrine stimulation plays an important role in the proliferation of ALL.

Anti-tumor immunity of gene vaccine with nucleofection technology

ObjectiveTo observe enhancement of anti-tumor immunity by gene vaccine using nucleofection technologyMethodsThe technique of nucleofection was used to transfer effectively plasmid DNA into immature dendritic cells (iDCs); we studied immune responses regulated by DNA vaccine using real-time quantitative polymerase chain reaction (PCR) and western-blotting to optimize the follow-up lymphocyte activation. The anti-tumor capacity of lymphocytes primed by DCs was analyzed using lactate dehydrogenase with a non-radioactive cytotoxicity assayResultsHuman monocyte-derived dendritic cells (hMoDCs) were induced by interleukin (IL)-4 and granulocyte-macrophage colonystimulating factor (GM-CSF) in vitro from human monocytes for 5 or 6 days. DNA vaccine was transfected to iDCs with high transfection (35.73%) using nucleofection. Compared with the iDC group, the expression of Th1 cell cytokine IL-12, IL-18 and Th2 cell cytokine IL-4 increased after stimulation. CD86 and CD83 were upregulated compared with non-nucleofected groups 48 hours after nucleofection with DC-pVAX-PRA. The result of the cytotoxicity assay showed that DCs-pVAX-PRA primed non-adherent peripheral blood mononuclear cells (PBMCs) exhibit their highest cytotoxicity against target cells.ConclusionThe results show that DNA vaccine was transfected to iDC with high transfection efficiency using nucleofection, priming autologous lymphocytes for anti-tumor immunity by upregulated expression of co-stimulatory molecules, adhesion molecules and cytokines. These results provided a basis to explore the molecular mechanism of DNA vaccine in vivo.

Morphological and Molecular Analysis of Angiogenesis after Intramyocardial Transplantation of Autologous Bone Marrow Mononuclear Cells

We studied the peculiarities of angiogenesis in the postinfarction period after transmyocardial laser revascularization and intramyocardial implantation of mononuclear bone marrow cells into the pericicatrical zone of the left ventricular myocardium in dogs. Morphological manifestation of angiogenesis in the myocardium after application of laser and cell technologies are angiomatosis, formation of large thin-wall vessels and sinusoids. The angiogenic effect of implanted mononuclear bone marrow cells is determined by high content (43-47%) of CD31+ cells in both adherent and nonadherent fractions. More pronounced angiogenic potential of nonadherent cells is determined by intensive expression of cytokine VEGF-B and D mRNA essential for arterial vessels growth. Immunohistochemical studies showed that about 90% cells of the nonadherent fraction are endothelial precursors expressing endothelial cell markers isolectin B4 and VEGF-R2. It was found that the use of adherent mononuclear bone marrow cells during the postinfarction period induces ossification of the epicardium and subepicardial myocardium layer, formation of cartilage plates, and focal calcification. Implantation of nonadherent mononuclear bone marrow cells into transmyocardial laser channels did not induce ectopic ossification of the myocardium.

Highly efficient lentiviral transduction of phenotypically and genotypically characterized endothelial progenitor cells from adult peripheral blood

Postnatal vasculogenesis has been implicated as an important mechanism for neovascularization via bone marrow-derived endothelial progenitor cells (EPCs) circulating in peripheral blood. In preparation of the utilization of EPCs in clinical protocols, we have generated blood-derived EPCs according to two established protocols by culturing either nonadherent mononuclear cells on fibronectin or adherent mononuclear cells on collagen. To explore the feasibility of these EPCs for their potential clinical use as target cells for genetic transduction to enhance their thromboresistance, newly designed retroviral and lentiviral gene ontology expression vectors were tested. Whereas cell clusters derived from the nonadherent cells demonstrated an only limited proliferative potential, cell colonies derived from collagen-adherent cells expanded more than a million-fold. Characterization of the exponentially growing cells by surface antigen and gene expression profiling revealed a consistently strong expression of characteristic endothelial markers, whereas expression of leukocyte markers was gradually lost. Using a single-step transduction protocol, we were able to achieve gene transfer efficiency of up to 99%. Our results suggest that the generated blood-derived EPC population might be attractive target cells for tissue engineering and gene therapy protocols due to their well defined phenotype, extensive proliferative potential, and efficient genetic transducibility, three important qualities that need to be defined prior to any clinical use.

Anticryptococcal cytotoxicity of murine nonadherent cells is perforin and nonperforin mediated

The encapsulated fungal pathogen Cryptococcus neoformans is a significant agent of life-threatening infections, particularly in people with suppressed cell-mediated immunity. The cellular cytotoxicity against C. neoformans infection is mainly mediated by NK and T cells, but effector mechanisms are not well understood. The objective of this study was (i) to determine whether prior exposure to the cryptococcal antigens enhances anticryptococcal activity of cytotoxic cells in mice and (ii) the contribution of perforin- and nonperforin-mediated cytotoxicity of NK and T cells in growth inhibition of C. neoformans. Our data showed that in vitro exposure of nonadherent (NA) spleen mononuclear cells from nonimmunized mice to heat-killed C. neoformans strain Cap67 unencapsulated mutant of B3501 (Ag1) or its supernatant (Ag2) demonstrated higher anticryptococcal activity. This effector mechanism can be enhanced further after immunization with either Ag1 or Ag2. There is a synergistic effect of immunization and in vitro incubation of the NA cells with the same antigens. Concanamycin A (CMA) and strontium chloride (SrCl2) inhibition assays were performed to clarify the contribution of perforin- and nonperforin-mediated anticryptococcal cytotoxicity of NA cells in these events. Treatment with these inhibitors demonstrated that anticryptococcal cytotoxicity of non-primed NA cells was primarily perforin mediated. Anticryptococcal activity of the NA cells obtained from immunized mice after in vitro incubation with cryptococcal antigens was both perforin and non-perforin mediated. Taken together these data demonstrate that in mice a nonperforin-mediated pathway of anticryptococcal cytotoxicity can be induced by immunization. Further research is needed to examine their potential role for human vaccines strategies and/or therapies.

Acute myelogenous leukemia blasts contribute to a bone marrow-stroma in in vivo NOD/SCID mouse system

Abstract Abstract 1621 Poster Board I-647 Aims: Cancer stem cell theory has been developed, and whose precise characteristics have been reported. However, there have been no reports on the differentiation of cancer stem cells into the environmental stromal cells. We reported previously that non-adherent acute myelogenous leukemia (AML) cells were differentiated into myofibroblasts to create a microenvironment for proliferation of AML blasts in vitro. In this report we demonstrate that with severe combined immunodeficiency (SCID) mouse system AML blast cells also convert to myofibroblasts to form stroma in vivo. Materials and Methods Bone marrow cells were collected from informed AML (M2) patients who had chromosomal translocation of RUNX1 and ETO, from which mononuclear cells were separated with density-gradient sedimentation method. After discarded an adherent cell-fraction, the non-adherent mononuclear cells were injected to the 3.0 Gray-irradiated non-obese diabetes (NOD)/SCID mouse intravenously. For the inactivation of NK cells, anti-Asialo GM1 antibody was injected intra-peritoneally prior to the transplantation, and on each 11th day thereafter. Blood was collected to monitor Runx1 and ETO fusion transcript, and mice were sacrificed after chimeric mRNA was observed. Bone marrow cells were obtained, and sorted with anti-human CD133 antibody and -CD106 to select AML-derived human stromal myofibroblasts referred to the in vitro data. The isolated positive fraction was further cultured, and the biological and the molecular characteristics were analyzed. Results and Discussion When non-adherent AML (M2) blast cells were transplanted to NOD/SCID mice, cells were engrafted after 10 weeks. In murine bone marrow cells human stromal cells were identified, in which RUNX1 and ETO gene was fused with FISH analysis. When the parental AML blast cells were cultured on the expanded AML-derived myofibroblasts, AML cells grew extensively. These results indicate that AML cells can create their own microenvironment for proliferation in vivo. Disclosures No relevant conflicts of interest to declare.