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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 19 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2019

Cellular Composition and Expression of Cell Proliferation and Apoptosis Markers in Bone Marrow Cells after Heterotransplantation

The effects of heterotransplantation on bone marrow structures were studied in experimental male mice. Suspension of the bone marrow from feline femur (1 ml bone marrow diluted in isotonic saline, 1:2) was injected into the caudal vein. Heterotransplantation led to an increase in the level of serotonin involved in cell differentiation. In 2 days, the counts of all cells except erythroid cells decreased. Immunohistochemical analysis of Ki-67 marker within 40 min after transplantation showed a significant increase of cell proliferative activity in comparison with that in intact mice. At later terms, the expression of Ki-67 in bone marrow cells decreased, while the expression of apoptosis regulator P-53 increased, which was associated with the presence of numerous dead cells.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2025

Metabolomic and transcriptomic remodeling of bone marrow myeloid cells in response to maternal obesity

Maternal obesity puts the offspring at high risk of developing obesity and cardiometabolic diseases in adulthood. Here, we utilized a mouse model of maternal high-fat diet (HFD)-induced obesity that recapitulates metabolic perturbations seen in humans. We show increased adiposity in the offspring of HFD-fed mothers (Off-HFD) when compared with the offspring of regular diet-fed mothers (Off-RD). We have previously reported significant immune perturbations in the bone marrow of newly weaned Off-HFD. Here, we hypothesized that lipid metabolism is altered in the bone marrow of Off-HFD versus Off-RD. To test this hypothesis, we investigated the lipidomic profile of bone marrow cells collected from 3-week-old Off-RD and Off-HFD. Diacylglycerols (DAGs), triacylglycerols (TAGs), sphingolipids, and phospholipids were remarkably different between the groups, independent of fetal sex. Levels of cholesteryl esters were significantly decreased in Off-HFD, suggesting reduced delivery of cholesterol. These were accompanied by age-dependent progression of mitochondrial dysfunction in bone marrow cells. We subsequently isolated CD11b+ myeloid cells from 3-wk-old mice and conducted metabolomic, lipidomic, and transcriptomic analyses. The lipidomic profiles of myeloid cells were similar to those of bone marrow cells and included increases in DAGs and decreased TAGs. Transcriptomics revealed altered expression of genes related to immune pathways, including macrophage alternative activation, B-cell receptors, and transforming growth factor-β signaling. All told, this study revealed lipidomic, metabolomic, and gene expression abnormalities in bone marrow cells broadly, and in bone marrow myeloid cells particularly, in the newly weaned offspring of mothers with obesity, which might at least partially explain the progression of metabolic and cardiovascular diseases in their adulthood.

RNA sequencing↗
DOE OSTI2018

ATP6V1H regulates the growth and differentiation of bone marrow stromal cells

Highlights: • Lack of ATP6V1H inhibits the proliferation of bone marrow stromal cells (BMSCs). • Partial loss of ATP6V1H inhibits osteogenic differentiation and promotes adipogenic differentiation of BMSCs. • ATP6V1H interacts with TGF-β receptor I and AP-2 complex to regulate the proliferation and differentiation of BMSCs. ATP6V1H encodes subunit H of vacuolar ATPase (V-ATPase) and may regulate osteoclastic function. The deficiency of ATP6V1H caused bone loss in human, mouse and zebrafish. In this report, we identified the mechanisms by which ATP6V1H regulates proliferation and differentiation of bone marrow stromal cells (BMSCs). We found that ATP6V1H was expressed in BMSCs, and Atp6v1h{sup +/-} BMSCs exhibited the lower proliferation rate, cell cycle arrest and reduced osteogenic differentiation capacity, as well as the increased adipogenic potentials. Histologic analysis confirmed less bone formation and more fatty degeneration in Atp6v1h{sup +/-} mice in the different age groups. Q-PCR analysis revealed that loss of ATP6V1H function downregulated the mRNA level of TGF-β1 receptor, and its binding molecule, subunit β of adaptor protein complex 2 (AP-2), suggesting ATP6V1H regulates the proliferation and differentiation of BMSCs by interacting with TGF-β receptor I and AP-2 complex.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2021

A bioinspired and chemically defined alternative to dimethyl sulfoxide for the cryopreservation of human hematopoietic stem cells

Abstract The cryopreservation of hematopoietic cells using dimethyl sulfoxide (DMSO) and serum is a common procedure used in transplantation. However, DMSO has clinical and biological side effects due to its toxicity, and serum introduces variation and safety risks. Inspired by natural antifreeze proteins, a novel class of ice-interactive cryoprotectants was developed. The corresponding DMSO-, protein-, and serum-free cryopreservation media candidates were screened through a series of biological assays using human cell lines, peripheral blood cells, and bone marrow cells. XT-Thrive-A and XT-Thrive-B were identified as lead candidates to rival cryopreservation with 10% DMSO in serum based on post-thaw cell survival and short-term proliferation assays. The effectiveness of the novel cryopreservation media in freezing hematopoietic stem cells from human whole bone marrow was assessed by extreme limiting dilution analysis in immunodeficient mice. Stem cell frequencies were measured 12 weeks after transplant based on bone marrow engraftment of erythroid, myeloid, B-lymphoid, and CD34 + progenitors measured by flow cytometry. The recovered numbers of cryopreserved stem cells were similar among XT-Thrive A, XT-Thrive B, and DMSO with serum groups. These findings show that cryoprotectants developed through biomimicry of natural antifreeze proteins offers a substitute for DMSO-based media for the cryopreservation of hematopoietic stem cells.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2021

Hypoxia-cultured mouse mesenchymal stromal cells from bone marrow and compact bone display different phenotypic traits

Highlights: • Mouse compact bone is richer in MSC compared to central bone marrow. • Derivation of MSC from mouse compact bone is associated with lower risk of contamination with hematopoietic cells. • MSC from compact bone display higher osteogenic differentiation capacity than bone marrow MSC. It has been suggested that the bone marrow microenvironment harbors two distinct populations of mesenchymal stromal cells (MSC), one with a perivascular location and other present in the endosteum. A better understanding of the biology of these MSC subsets has been pursued in order to refine its clinical application. However, most comparative characterizations of mouse MSC have been performed in normoxia. This can result in misleading interpretations since mouse MSC subsets with low/defective p53 activity are known to be selected during culture in normoxia. Here, we report a comprehensive in vitro characterization of mouse MSC isolated from bone marrow (BM-MSC) and compact bone (CB-MSC) expanded and assayed under hypoxia for their morphology, clonogenic efficiency and differentiation capacity. We found that, under hypoxia, compact bone is richer in absolute numbers of MSC and isolation of MSC from compact bone is associated with a reduced risk of hematopoietic cell carryover. In addition, CB-MSC have higher in vitro osteogenic capacity than BM-MSC, while adipogenic differentiation potential is similar. These findings reinforce the hypothesis of the existence of MSC in bone marrow and compact bone representing functionally distinct cell populations and highlight the compact bone as an efficient source of murine MSC under physiological oxygen concentrations.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2018

The orphan nuclear receptor EAR-2 (NR2F6) inhibits hematopoietic cell differentiation and induces myeloid dysplasia in vivo

Background: In patients with myelodysplastic syndrome (MDS), bone marrow cells have an increased predisposition to apoptosis, yet MDS cells outcompete normal bone marrow (BM)–suggesting that factors regulating growth potential may be important in MDS. We previously identified v-Erb A related-2 (EAR-2, NR2F6) as a gene involved in control of growth ability. Methods: Bone marrow obtained from C57BL/6 mice was transfected with a retrovirus containing EAR-2-IRES-GFP. Ex vivo transduced cells were flow sorted. In some experiments cells were cultured in vitro, in other experiments cells were injected into lethally irradiated recipients, along with non-transduced bone marrow cells. Short-hairpin RNA silencing EAR-2 was also introduced into bone marrow cells cultured ex vivo. Results: Here, we show that EAR-2 inhibits maturation of normal BM in vitro and in vivo and that EAR-2 transplant chimeras demonstrate key features of MDS. Competitive repopulation of lethally irradiated murine hosts with EAR2-transduced BM cells resulted in increased engraftment and increased colony formation in serial replating experiments. Recipients of EAR-2-transduced grafts had hypercellular BM, erythroid dysplasia, abnormal localization of immature precursors and increased blasts; secondary transplantation resulted in acute leukemia. Animals were cytopenic, having reduced numbers of erythrocytes, monocytes and granulocytes. Suspension culture confirmed that EAR-2 inhibits granulocytic and monocytic differentiation, while knockdown induced granulocytic differentiation. We observed a reduction in the number of BFU-E and CFU-GM colonies and the size of erythroid and myeloid colonies. Serial replating of transduced hematopoietic colonies revealed extended replating potential in EAR-2-overexpressing BM, while knockdown reduced re-plating ability. EAR-2 functions by recruitment of histone deacetylases, and inhibition of differentiation in 32D cells is dependent on the DNA binding domain. Conclusions: This data suggest that NR2F6 inhibits maturation of normal BM in vitro and in vivo and that the NR2F6 transplant chimera system demonstrates key features of MDS, and could provide a mouse model for MDS.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2018

Long non-coding RNA, Bmcob, regulates osteoblastic differentiation of bone marrow mesenchymal stem cells

Disordered osteoblastic differentiation of bone marrow mesenchymal stem cells (BMSCs) contributes to bone loss. The underlying mechanisms are complicated and not fully understood. Long non-coding RNAs (lncRNAs) are emerging as an important regulatory factors on bone metabolism. Here, we discovered a novel lncRNA, Bmcob, which modulated osteogenic differentiation of primary mouse BMSCs. Expression levels of Bmcob were significantly upregulated in early-to-mid stages during osteoblast differentiation. Silencing of Bmcob suppressed osteoblastic differentiation of BMSCs in vitro, whereas its overexpression protected BMSCs from oxidative stress induced inhibition on osteogenesis. Subsequently, we discovered that selenoprotein P (Sepp1), which is located next to the Bmcob gene, was partly responsible for the regulatory effects of Bmcob. In addition, a series of selenoproteins were downregulated in BMSCs with Bmcob knockdown. Mechanistically, we found Bmcob was associated with selenocysteine insertion sequence binding protein 2 (SBP2), a critical trans-acting factor for selenoprotein synthesis. Finally, we suggest an explanatory hypothesis that through modulating nucleocytoplasmic shuttling of SBP2, Bmcob regulates a number of selenoproteins expression, including sepp1, and then mediates osteogenesis of BMSCs. Taken together, our results revealed a novel mechanism regulating osteogenesis of BMSCs and may function as a potential target for treating osteoporosis.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2018

Viability of Different Types of Cells Cultivated on the Surface of Medical Electret

The effect of the electric field of a medical electret on the basis of tantalum pentoxide (Ta{sub 2}O{sub 5}) on the viability of human fibroblasts, multipotent mesenchymal stromal bone marrow cells, osteocytes, and chondrocytes cultivated on the surface of tantalum orthopedic implants with an electret coating was studied in vitro. Using the methods of photocolorimetic analysis and scanning electron microscopy, difference in the metabolic activity and cell morphology, in the character of the cell attachment to the implants and distribution by their surface, associated with the value and character of the electric charge distribution on the surface of these implants and the type of cellular test systems, were detected. Unclear mechanisms of the effect of the electric field of medical electrets on the functional activity of different types of the organism cell and tissues dictate the need for further experimental developments and fundamental studies in this field.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
DOE OSTI2018

Comparative characterization of stem cells from human exfoliated deciduous teeth, dental pulp, and bone marrow–derived mesenchymal stem cells

Highlights: • We compared the in vitro characteristics of dental pulp stem cells from deciduous teeth (SHED), human dental pulp stem cells (hDPSCs), and human bone marrow mesenchymal stem cells (hBMSCs). • SHED exhibit greater proliferative potential than hDPSCs and hBMSCs. • SHED exhibited higher proliferative activity and levels of bFGF and BMP-2 gene expression compared with BMMSCs and DPSCs. The ease of harvesting cells and ability to avoid invasive surgical procedures suggest that SHED may be a useful cell source for application in bone regeneration treatments. Mesenchymal stem cells (MSCs) are used clinically in tissue engineering and regenerative medicine. The proliferation and osteogenic differentiation potential of MSCs vary according to factors such as tissue source and cell population heterogeneity. Dental tissue has received attention as an easily accessible source of high-quality stem cells. In this study, we compared the in vitro characteristics of dental pulp stem cells from deciduous teeth (SHED), human dental pulp stem cells (hDPSCs), and human bone marrow mesenchymal stem cells (hBMSCs).

60 APPLIED LIFE SCIENCES↗
DOE OSTI2021

The protein 4.1R downregulates VEGFA in M2 macrophages to inhibit colon cancer metastasis

Highlights: • Protein 4.1R knockout reduced the phagocytosis of M2 macrophages. • Co-culture with 4.1R knockout M2 macrophages enhances the malignancy of colon cancer. • Protein 4.1R knockout upregulates vascular endothelial growth factor A secreted by M2 macrophages. • Protein 4.1R knockout activates the PI3K/AKT signaling pathway and promotes the progression of colon cancer. M2 macrophages are crucial components of the tumour microenvironment and have been shown to be closely related to tumour progression. Co-culture with 4.1R{sup −/−} M2 macrophages enhances the malignancy of colon cancer (CC), but the mechanism remains unclear. Here, we report that protein 4.1R knockout reduced the phagocytosis of M2 macrophages (M-CSF/IL-4-treated bone marrow cells) and promoted MC38 colon cancer cell proliferation, migration, invasion, tumour formation and epithelial-mesenchymal transition (EMT), which are regulated by M2 macrophages. Further mechanistic dissection revealed that the 4.1R knockout upregulated vascular endothelial growth factor A (VEGFA) secreted by M2 macrophages and promoted colon cancer progression by activating the PI3K/AKT signalling pathway. In summary, our present study identified that 4.1R downregulates VEGFA secretion in M2 macrophages and delays the malignant potential of colon cancer by inhibiting the PI3K/AKT signalling pathway.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2018

Isolation and characterization of endothelial colony-forming cells from mononuclear cells of rat bone marrow

Highlights: • BM-ECFCs are isolated from rat bone marrow with high purity by an optimized method. • Primary colony BM-ECFCs highly display CD34{sup +}/CD133{sup +}/VEGFR2{sup +}. • BM-ECFCs possess and maintain pronounced angiogenic abilities during the expansion. • BM-ECFCs spontaneously form tube-like structures during culture without Matrigel. Transplantation of bone marrow-derived endothelial progenitor cells (BM-EPCs) has been used as a therapeutic strategy for vascular repair. However, it remains controversial whether BM-EPCs exhibit clonal endothelial colony-forming cell (ECFC) capacity, a characteristic of true EPCs. The aim of this study was to isolate and explore the cellular properties of BM-ECFCs. We isolated BM-ECFCs from rat bone marrow with high purity via an optimized method. This approach involved the removal of selective colonies based on the conventional differential adhesive culture method used to isolate ECFCs from peripheral and umbilical cord blood. Our results indicate that primary colony BM-ECFCs display a panel of surface antigen markers consistent with endothelial cells. These BM-ECFCs coexpress CD34, CD133, and VEGFR2 at high levels, and these levels decrease with passaging. These cells have high potential for proliferation, migration, and formation of capillary-like structures on Matrigel, and these abilities are retained during ex vivo expansion. Furthermore, BM-ECFCs cultured with 10% or 20% fetal bovine serum demonstrated two different patterns of spontaneous capillary-like structure formation. These results provide a foundation for isolation of ECFCs from human bone marrow for autologous cell transplantation and tissue engineering applications in the future.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2021

Exosomes derived from hypoxic bone marrow mesenchymal stem cells rescue OGD-induced injury in neural cells by suppressing NLRP3 inflammasome-mediated pyroptosis

Exosomes have been shown to have therapeutic potential for cerebral ischemic diseases. In this study, we investigated the neuroprotective effects of normoxic and hypoxic bone marrow mesenchymal stromal cells-derived exosomes (N-BM-MSCs-Exo and H-BM-MSCs-Exo, respectively) on oxygen-glucose deprivation (OGD) injury in mouse neuroblastoma N2a cells and rat primary cortical neurons. The proportions of dead cells in N2a and primary cortical neurons after OGD injury were significantly increased, and N-BM-MSCs-Exo (40 μg/ml) could reduce the ratios, noteworthily, the protective effects of H-BM-MSCs-Exo (40 μg/ml) were more potent. Western blotting analysis indicated that N-BM-MSCs-Exo decreased the expression of NLRP3, ASC, Caspase-1, GSDMD-N, cleaved IL-1β and IL-18 in N2a cells. However, H-BM-MSCs-Exo (40 μg/ml) was more powerful in inhibiting the expression of these proteins in comparison with N-BM-MSCs-Exo. Similar results were obtained in primary cortical neurons. Immunofluorescence assays showed that after N-BM-MSCs-Exo and H-BM-MSCs-Exo treatment, the co-localization of NLRP3, ASC, Caspase-1 and the GSDMD translocation from the nucleus to the cytoplasm and membrane after OGD injury were reduced in N2a cells and primary cortical neurons, and H-BM-MSCs-Exo had a more obvious effect. In addition, N-BM-MSCs-Exo and H-BM-MSCs-Exo significantly reduced lactate dehydrogenase (LDH) release and the IL-18 levels in cell culture medium in N2a cells and primary cortical neurons. Once again H-BM-MSCs-Exo induced these effects more potently than N-BM-MSCs-Exo. All of these results demonstrated that N-BM-MSCs-Exo and H-BM-MSCs-Exo have significant neuroprotective effects against NLRP3 inflammasome-mediated pyroptosis. H-BM-MSCs-Exo has a more pronounced protective effect than N-BM-MSCs-Exo and may be used to ameliorate the progression of cerebral ischemia and hypoxia injury in patients.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2018

Staphylococcal enterotoxin C2 stimulated the maturation of bone marrow derived dendritic cells via TLR-NFκB signaling pathway

Highlights: • SEC2 stimulate the maturation of BMDCs. • SEC2 induce the production of pro-inflammation cytokines in BMDCs. • SEC2 activate NF-κB signaling pathway in BMDCs. As a kind of superantigen, staphylococcal enterotoxin C2 (SEC2) is well known as a powerful immunomodulator. However, most previous studies about SEC2 focus on its T cell activating characters. But the direct effect of SEC2 on antigen-presenting cells (APCs) which are important for the T cell activation is not clearly. In this study, we investigated the effect of SEC2 on murine bone marrow-derived dendritic cells (BMDCs) which are known as the specialized professional APCs. Contrary to its effects on T cells, SEC2 could not induce proliferation or cytotoxicity to BMDCs even in high concentrations. While SEC2 could promote the mature of BMDCs with increased expression of co-stimulatory molecules on cell membrane such as CD80, CD86, and MHC II. The production of pro-inflammatory cytokines such as TNF-α, IFN-γ and IL-6 were also increased in BMDCs treated with SEC2. We also found that SEC2 enhanced the genes expression of pattern recognition receptors including toll-like receptors 2 (TLR2) and TLR4 in BMDCs, and up-regulated the key signal molecule MyD88 in both mRNA and protein levels. In addition, SEC2 also caused IκBα degradating and NFκB p65 translocating from the cytoplasm to the nucleus in BMDCs. The siRNAs for both TLR2 and TLR4, as well as NFκB specific inhibitor BAY 11–7085 could inhibit the co-stimulatory molecules expression and pro-inflammatory cytokines releasing induced by SEC2. Moreover, TLR2/4 specific siRNAs inhibited p65 and MyD88 upregulation induced by SEC2. In summary, all our results indicated that SEC2 could stimulate BMDCs maturation through TLR-NFκB signaling pathways.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2019

Direct Write Assembly of Graphene/Poly(ε-Caprolactone) Composite Scaffolds and Evaluation of Their Biological Performance Using Mouse Bone Marrow Mesenchymal Stem Cells

Scaffold and mesenchymal stem cell–based cartilage tissue engineering offers a favorable way for the repair and regeneration of injured cartilage. In this study, poly (ε-caprolactone) PCL scaffolds with grid-like structure having periodic lattice was manufactured by robocasting method in the presence of graphene nanoplatelets for cartilage tissue engineering applications. For this purpose, a PCL solution (20 wt%) containing pristine graphene nanopowders in the form of platelets was prepared as printing ink and it was dispensed through a nozzle at room temperature to an ethanol bath at 4 °C. The construction of porous scaffolds was made by a layer-by-layer assembly. Results revealed that graphene additions were not detrimental to deposition process and the structure of the resultant scaffolds. In vitro cell tests indicated that the prepared grid-like graphene/PCL composite scaffolds have good cytocompatibility and non-toxicity for mouse bone marrow mesenchymal stem cells. The stem cells attached and proliferated well on the scaffolds and they also demonstrated a chondrogenic differentiation in the absence of transforming growth factors.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2019

Copper Transporter ATP7A (Copper-Transporting P-Type ATPase/Menkes ATPase) Limits Vascular Inflammation and Aortic Aneurysm Development: Role of MicroRNA-125b

Objective: Copper (Cu) is essential micronutrient, and its dysregulation is implicated in aortic aneurysm (AA) development. The Cu exporter ATP7A (copper-transporting P-type ATPase/Menkes ATPase) delivers Cu via the Cu chaperone Atox1 (antioxidant 1) to secretory Cu enzymes, such as lysyl oxidase, and excludes excess Cu. Lysyl oxidase is shown to protect against AA formation. However, the role and mechanism of ATP7A in AA pathogenesis remain unknown. Approach and Results: Here, in this work, we show that Cu chelator markedly inhibited Ang II (angiotensin II)–induced abdominal AA (AAA) in which ATP7A expression was markedly downregulated. Transgenic ATP7A overexpression prevented Ang II–induced AAA formation. Conversely, Cu transport dysfunctional ATP7A mut/+ /ApoE –/– mice exhibited robust AAA formation and dissection, excess aortic Cu accumulation as assessed by X-ray fluorescence microscopy, and reduced lysyl oxidase activity. In contrast, AAA formation was not observed in Atox1 –/– /ApoE –/– mice, suggesting that decreased lysyl oxidase activity, which depends on both ATP7A and Atox1, was not sufficient to develop AAA. Bone marrow transplantation suggested importance of ATP7A in vascular cells, not bone marrow cells, in AAA development. MicroRNA (miR) array identified miR-125b as a highly upregulated miR in AAA from ATP7A mut/+ /ApoE –/– mice. Furthermore, miR-125b target genes (histone methyltransferase Suv39h1 and the NF-κB negative regulator TNFAIP3 [tumor necrosis factor alpha induced protein 3]) were downregulated, which resulted in increased proinflammatory cytokine expression, aortic macrophage recruitment, MMP (matrix metalloproteinase)-2/9 activity, elastin fragmentation, and vascular smooth muscle cell loss in ATP7A mut/+ /ApoE –/– mice and reversed by locked nucleic acid-anti-miR-125b infusion. Conclusions: ATP7A downregulation/dysfunction promotes AAA formation via upregulating miR-125b, which augments proinflammatory signaling in a Cu-dependent manner. Thus, ATP7A is a potential therapeutic target for inflammatory vascular disease.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2024

Morphologic characterization and cytokine response of chicken bone-marrow derived dendritic cells to infection with high and low pathogenic avian influenza virus

Dendritic cells (DCs) are professional antigen-presenting cells, which are key components of the immune system and involved in early immune responses. DCs are specialized in capturing, processing, and presenting antigens to facilitate immune interactions. Chickens infected with avian influenza virus (AIV) demonstrate a wide range of clinical symptoms, based on pathogenicity of the virus. Low pathogenic avian influenza (LPAI) viruses typically induce mild clinical signs, whereas high pathogenic avian influenza (HPAI) induce more severe disease, which can lead to death. For this study, chicken bone marrow-derived DC (ckBM-DC)s were produced and infected with high and low pathogenic avian influenza viruses of H5N2 or H7N3 subtypes to characterize innate immune responses, study effect on cell morphologies, and evaluate virus replication. A strong proinflammatory response was observed at 8 hours post infection, via upregulation of chicken interleukin-1β and stimulation of the interferon response pathway. Microscopically, the DCs underwent morphological changes from classic elongated dendrites to a more general rounded shape that eventually led to cell death with the presence of scattered cellular debris. Differences in onset of morphologic changes were observed between H5 and H7 subtypes. Increases in viral titers demonstrated that both HPAI and LPAI are capable of infecting and replicating in DCs. The increase in activation of infected DCs may be indicative of a dysregulated immune response typically seen with HPAI infections.

Immunology↗
DOE OSTI2020

Intrafibrillar Mineralized Collagen–Hydroxyapatite-Based Scaffolds for Bone Regeneration

As one of the major challenges in the field of tissue engineering, large skeletal defects have attracted wide attention from researchers. Collagen (Col) and hydroxyapatite (HA), the most abundant protein and the main component in natural bone, resp., are usually used as a biomimetic composite material in tissue engineering due to their excellent biocompatibility and biodegradability. In this study, novel intrafibrillar mineralized Col-HA-based scaffolds, constructed in either cellular or lamellar microstructures, were established through a biomimetic method to enhance the new bone-regenerating capability of tissue engineering scaffolds. Moreover, iron (Fe) and manganese (Mn), two of the essential trace elements in the body, were successfully incorporated into the lamellar scaffold to further improve the osteoinductivity of these biomaterials. It was found that the lamellar scaffolds demonstrated better osteogenic abilities compared to both inhouse and com. Col-HA-based cellular scaffolds in vitro and in vivo. Meanwhile, Fe/Mn incorporation further amplified the osteogenic promotion of the lamellar scaffolds. More importantly, a synergistic effect was obsd. in the Fe and Mn dual-element-incorporated lamellar scaffolds for both in vitro osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) and in vivo bone regeneration loaded with fresh bone marrow cells. Furthermore, this study provides a simple but practical strategy for the creation of functional scaffolds for bone regeneration.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2018

Dual expression of CXCR4 and IL-35 enhances the therapeutic effects of BMSCs on TNBS-induced colitis in rats through expansion of Tregs and suppression of Th17 cells

Highlights: • CXCR4/IL-35 expression in BMSCs enhances their protective effects on colitis. • CXCR4/IL-35 expression promotes migration of BMSCs to inflamed colons. • CXCR4/IL-35 expression expands regulatory T cells and suppresses T helper 17 cells. Bone marrow-derived mesenchymal stem cells (BMSCs) hold great promise for the treatment of inflammatory bowel disease owing to their immunosuppressive property and tissue healing potential. The balance between regulatory T cells (Tregs) and T helper (Th)17 cells plays a crucial role in BMSC-mediated immunosuppression. Interleukin (IL)-35 is a newly identified anti-inflammatory cytokine required for the expansion of Tregs and suppression of Th17 cell differentiation. IL-35 can amplify the immunosuppressive property of BMSCs when overexpressed in these cells. However, the reparative capability of BMSCs in vivo is limited, partly due to the poor homing efficiency of BMSCs to inflamed colons. Up-regulation of CXC chemokine receptor 4 (CXCR4) expression in BMSCs may affect the directional homing of implanted BMSCs via stromal-derived factor-1. In this study, by lentivirus-mediated introduction of CXCR4 and IL-35 genes to modify rat BMSCs, we observed enhanced migration and strengthened immunomodulatory activities of the genetically engineering BMSCs. These results suggest that modification of BMSCs by dual expression of CXCR4 and IL-35 may provide an effective therapeutic strategy for inflammatory bowel disease.

60 APPLIED LIFE SCIENCES↗