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Structural parameters of the implants such as shape, size, and porosity of the pores have been extensively investigated to promote bone tissue repair, however, it is unknown how the pore interconnectivity affects the bone growth behaviors in the scaffolds. Herein we systematically evaluated the effect of biodegradable bioceramics as a secondary phase filler in the macroporous networks on the mechanical and osteogenic behaviors in sparingly dissolvable bioceramic scaffolds. The pure hardystonite (HT) scaffolds with â¼550 & 800 µm in pore sizes were prepared by digital light processing, and then the Sr-doped calcium silicate (SrCSi) bioceramic slurry without and with 30 % organic porogens were intruded into the HT scaffolds with 800 µm pore size and sintered at 1150 °C. It indicated that the organic porogens could endow spherical micropores in the SrCSi filler, and the invasion of the SrCSi component could not only significantly enhance the compressive strength and modulus of the HT-based scaffolds, but also induce osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs). The pure HT scaffolds showed extremely slow bio-dissolution in Tris buffer after immersion for 8 weeks (â¼1 % mass decay); in contrast, the SrCSi filler would readily dissolve into the aqueous medium and produced a steady mass decay (>6 % mass loss). In vivo experiments in rabbit femoral bone defect models showed that the pure HT scaffolds showed bone tissue ingrowth but the bone growth was impeded in the SrCSi-intruded scaffolds within 4 weeks; however, the group with higher porosity of SrCSi filler showed appreciable osteogenesis after 8 weeks of implantation and the whole scaffold was uniformly covered by new bone tissues after 16 weeks. These findings provide some new insights that the pore interconnectivity is not inevitable to impede bone ingrowth with the prolongation of implantation time, and such a highly biodegradable and bioactive filler intrusion strategy may be beneficial for optimizing the performances of scaffolds in bone regenerative medicine applications.
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Pore parameters, structural stability, and filler morphology of artificial implants are key factors influencing the process of bone tissue repair. However, the extent to which each of these factors contributes to bone formation in the preparation of porous bioceramics is currently unclear, with the two often being coupled. Herein, we prepared magnesium-doped wollastonite (Mg-CSi) scaffolds with 57% and 70% porosity (57-S and 70-S) via a 3D printing technique. Meanwhile, the bioceramic granules (57-G and 70-G) with curved pore topography (IWP) were prepared by physically disrupting the 57-S and 70-S scaffolds, respectively, and compared for in vivo osteogenesis at 4, 10, and 16 weeks. The pore parameters and the mechanical and biodegradable properties of different porous bioceramics were characterized systematically. The four groups of porous scaffolds and granules were then implanted into a rabbit femoral defect model to evaluate the osteogenic behavior in vivo. 2D/3D reconstruction and histological analysis showed that significant bone tissue production was visible in the central zone of porous granule groups at the early stage but bone tissue ingrowth was slower in the porous scaffold groups. The bone tissue regeneration and reconstruction capacity were stronger after 10 weeks, and the porous architecture of the 57-S scaffold was maintained stably at 16 weeks. These experimental results demonstrated that the structure-collapsed porous bioceramic is favorable for early-stage osteoconduction and that the 3D topological scaffolds may provide more structural stability for bone tissue growth for a long-term stage. These findings provide new ideas for the selection of different types of porous bioceramics for clinical bone repair.
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BACKGROUND: CD73 is an ecto-enzyme that is involved in the conversion of pro-inflammatory extracellular ATP (eATP) excreted by cancer cells under stress to anti-inflammatory adenosine (ADO). A broad variety of solid cancer types was shown to exploit CD73 overexpression as a suppressive immune checkpoint. Consequently, CD73-antagonistic antibodies, most notably oleclumab, are currently evaluated in several multicenter trials for clinical applicability. However, the efficacy of conventional monospecific CD73-inhibiting antibodies may be limited due to on-target/off-tumor binding to CD73 on normal cells. Therefore, a novel approach that more selectively directs CD73 immune checkpoint inhibition towards cancer cells is warranted. METHODS: To address this issue, we constructed a novel tetravalent bispecific antibody (bsAb), designated bsAb CD73xEGFR. Subsequently, the anticancer activities of bsAb CD73xEGFR were evaluated using in vitro and in vivo tumor models. RESULTS: In vitro treatment of various carcinoma cell types with bsAb CD73xEGFR potently inhibited the enzyme activity of CD73 (~71%) in an EGFR-directed manner. In this process, bsAb CD73xEGFR induced rapid internalization of antigen/antibody complexes, which resulted in a prolonged concurrent displacement of both CD73 and EGFR from the cancer cell surface. In addition, bsAb CD73xEGFR sensitized cancer to the cytotoxic activity of various chemotherapeutic agents and potently inhibited the proliferative/migratory capacity (~40%) of cancer cells. Unexpectedly, we uncovered that treatment of carcinoma cells with oleclumab appeared to enhance several pro-oncogenic features, including upregulation and phosphorylation of EGFR, tumor cell proliferation (~20%), and resistance towards cytotoxic agents and ionizing radiation (~39%). Importantly, in a tumor model using immunocompetent BALB/c mice inoculated with syngeneic CD73pos/EGFRpos CT26 cancer cells, treatment with bsAb CD73xEGFR outperformed oleclumab (65% vs 31% tumor volume reduction). Compared with oleclumab, treatment with bsAb CD73xEGFR enhanced the intratumoral presence of CD8pos T cells and M1 macrophages. CONCLUSIONS: BsAb CD73xEGFR outperforms oleclumab as it inhibits the CD73/ADO immune checkpoint in an EGFR-directed manner and concurrently counteracts several oncogenic activities of EGFR and CD73. Therefore, bsAb CD73xEGFR may be of significant clinical potential for various forms of difficult-to-treat solid cancer types.
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Anticorpos Biespecíficos , Neoplasias , Animais , Camundongos , Anticorpos Biespecíficos/farmacologia , Anticorpos Biespecíficos/uso terapêutico , Membrana Celular , Adenosina , Anticorpos Monoclonais , Receptores ErbB , Neoplasias/tratamento farmacológicoRESUMO
PD-1/PD-L1-inhibiting antibodies have shown disappointing efficacy in patients with refractory ovarian cancer (OC). Apparently, OC cells exploit nonoverlapping immunosuppressive mechanisms to evade the immune system. In this respect, the CD73-adenosine inhibitory immune checkpoint is of particular interest, as it rapidly converts pro-inflammatory ATP released from cancer cells to immunosuppressive adenosine (ADO). Moreover, cancer-cell-produced ADO is known to form a highly immunosuppressive extra-tumoral 'halo' that chronically inhibits the anticancer activity of various immune effector cells. Thus far, conventional CD73-blocking antibodies such as oleclumab show limited clinical efficacy, probably due to the fact that it indiscriminately binds to and blocks CD73 on a massive surplus of normal cells. To address this issue, we constructed a novel bispecific antibody (bsAb) CD73xEpCAM that inhibits CD73 expressed on the OC cell surface in an EpCAM-directed manner. Importantly, bsAb CD73xEpCAM showed potent capacity to inhibit the CD73 enzyme activity in an EpCAM-directed manner and restore the cytotoxic activity of ADO-suppressed anticancer T cells. Additionally, treatment with bsAb CD73xEpCAM potently inhibited the proliferative capacity of OC cells and enhanced their sensitivity to cisplatin, doxorubicin, 5FU, and ionizing radiation. BsAb CD73xEpCAM may be useful in the development of tumor-directed immunotherapeutic approaches to overcome the CD73-mediated immunosuppression in patients with refractory OC.
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Typically, anticancer CD8pos T cells occur at low frequencies and become increasingly impaired in the tumor micro environment. In contrast, antiviral CD8pos T cells display a much higher polyclonality, frequency, and functionality. In particular, cytomegalovirus (CMV) infection induces high numbers of 'inflationary' CD8pos T cells that remain lifelong abundantly present in CMV-seropositive subjects. Importantly, these so-called inflationary anti-CMV T cells increase with age, maintain a ready-to-go state, populate tumors, and do not become exhausted or senescent. Given these favorable attributes, we devised a novel series of recombinant Fab-peptide-HLA-I fusion proteins and coined them 'ReTARGs'. A ReTARG fusion protein consists of a high-affinity Fab antibody fragment directed to carcinoma-associated cell surface antigen EpCAM (or EGFR), fused in tandem with soluble HLA-I molecule/ß2-microglobulin, genetically equipped with an immunodominant peptide derived from CMV proteins pp65 (or IE-1). Decoration with EpCAM-ReTARGpp65 rendered EpCAM-expressing primary patient-derived carcinoma cells highly sensitive to selective elimination by cognate anti-CMV CD8pos T cells. Importantly, this treatment did not induce excessive levels of proinflammatory T cell-secreted IFNγ. In contrast, analogous treatment with equimolar amounts of EpCAM/CD3-directed bispecific T-cell engager solitomab resulted in a massive release of IFNγ, a feature commonly associated with adverse cytokine-release syndrome. Combinatorial treatment with EpCAM-ReTARGpp65 and EGFR-ReTARGIE-1 strongly potentiated selective cancer cell elimination owing to the concerted action of the corresponding cognate anti-CMV CD8pos T cell clones. In conclusion, ReTARG fusion proteins may be useful as an alternative or complementary form of targeted cancer immunotherapy for 'cold' solid cancers.
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Infecções por Citomegalovirus , Citomegalovirus , Humanos , Molécula de Adesão da Célula Epitelial , Citomegalovirus/genética , Citomegalovirus/metabolismo , Linfócitos T , Interferon gama , Receptores ErbBRESUMO
Osteochondral tissue involves cartilage, calcified cartilage and subchondral bone. These tissues differ significantly in chemical compositions, structures, mechanical properties and cellular compositions. Therefore, the repairing materials face different osteochondral tissue regeneration needs and rates. In this study, we fabricated an osteochondral tissue-inspired triphasic material, which was composed of a poly(lactide-co-glycolide) (PLGA) scaffold loaded with fibrin hydrogel, bone marrow stromal cells (BMSCs) and transforming growth factor-ß1 (TGF-ß1) for cartilage tissue, a bilayer poly(L-lactide-co-caprolactone) (PLCL)-fibrous membrane loaded with chondroitin sulfate and bioactive glass, respectively, for calcified cartilage, and a 3D-printed calcium silicate ceramic scaffold for subchondral bone. The triphasic scaffold was press-fitted into the osteochondral defects in rabbit (cylindrical defects with a diameter of 4 mm and a depth of 4 mm) and minipig knee joints (cylindrical defects with a diameter of 10 mm and a depth of 6 mm). The µ-CT and histological analysis showed that the triphasic scaffold was partly degraded, and significantly promoted the regeneration of hyaline cartilage after they were implanted in vivo. The superficial cartilage showed good recovery and uniformity. The calcified cartilage layer (CCL) fibrous membrane was in favor of a better cartilage regeneration morphology, a continuous cartilage structure and less fibrocartilage tissue formation. The bone tissue grew into the material, while the CCL membrane limited bone overgrowth. The newly generated osteochondral tissues were well integrated with the surrounding tissues too.
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Biomimética , Alicerces Teciduais , Coelhos , Suínos , Animais , Alicerces Teciduais/química , Porco Miniatura , Cartilagem , Osso e OssosRESUMO
212Three-dimensional (3D) printing is a modern, computer-aided, design-based technology that allows the layer-by-layer deposition of 3D structures. Bioprinting, a 3D printing technology, has attracted increasing attention because of its capacity to produce scaffolds for living cells with extreme precision. Along with the rapid development of 3D bioprinting technology, the innovation of bio-inks, which is recognized as the most challenging aspect of this technology, has demonstrated tremendous promise for tissue engineering and regenerative medicine. Cellulose is the most abundant polymer in nature. Various forms of cellulose, nanocellulose, and cellulose derivatives, including cellulose ethers and cellulose esters, are common bioprintable materials used to develop bio-inks in recent years, owing to their biocompatibility, biodegradability, low cost, and printability. Although various cellulose-based bio-inks have been investigated, the potential applications of nanocellulose and cellulose derivative-based bio-inks have not been fully explored. This review focuses on the physicochemical properties of nanocellulose and cellulose derivatives as well as the recent advances in bio-ink design for 3D bioprinting of bone and cartilage. In addition, the current advantages and disadvantages of these bio-inks and their prospects in 3D printing-based tissue engineering are comprehensively discussed. We hope to offer helpful information for the logical design of innovative cellulose-based materials for use in this sector in the future.
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Artocarpus altilis (Parkinson ex F.A. Zorn) Fosberg is native to the Pacific Islands, India, and the Philippines. It is also cultivated in Taiwan and Hainan. The complete plastome of the species was assembled and annotated in this study. The circular genome was 160,184 bp in size, presenting a typical quadripartite structure including two inverted repeats (IRs) of 25,734 bp, a large single-copy (LSC) of 88,791 bp, and a small single-copy (SSC) of 19,925 bp. The genome contained 132 genes, including 87 protein-coding genes, 37 tRNA genes, and eight rRNA genes. The total G/C content of complete plastome was 36.0%, with the corresponding values of the LSC, SSC, and IR being 33.7%, 28.8%, and 42.7%, respectively. The complete plastome sequence of A. altilis (Parkinson ex F.A. Zorn) Fosberg will make contributions to the conservation genetics of this species as well as to phylogenetic studies of Moraceae.
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Cancer vaccines critically rely on the availability of targetable immunogenic cancer-specific neoepitopes. However, mutation-based immunogenic neoantigens are rare or even non-existent in subgroups of cancer types. To address this issue, we exploited a cancer-specific aberrant transcription-induced chimeric RNA, designated A-Pas chiRNA, as a possible source of clinically relevant and targetable neoantigens. A-Pas chiRNA encodes a recently discovered cancer-specific chimeric protein that comprises full-length astrotactin-2 (ASTN2) C-terminally fused in-frame to the antisense sequence of the 18th intron of pregnancy-associated plasma protein-A (PAPPA). We used extracellular vesicles (EVs) from A-Pas chiRNA-transfected dendritic cells (DCs) to produce the cell-free anticancer vaccine DEXA-P . Treatment of immunocompetent cancer-bearing mice with DEXA-P inhibited tumour growth and prolonged animal survival. In summary, we demonstrate for the first time that cancer-specific transcription-induced chimeric RNAs can be exploited to produce a cell-free cancer vaccine that induces potent CD8+ T cell-mediated anticancer immunity. Our novel approach may be particularly useful for developing cancer vaccines to treat malignancies with low mutational burden or without mutation-based antigens. Moreover, this cell-free anticancer vaccine approach may offer several practical advantages over cell-based vaccines, such as ease of scalability and genetic modifiability as well as enhanced shelf life.
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Vacinas Anticâncer , Vesículas Extracelulares , Neoplasias , Animais , Antígenos de Neoplasias/genética , Células Dendríticas , Camundongos , Neoplasias/terapia , RNA , VacinaçãoRESUMO
Diospyros nigra (J.F.Gmel.) M.R.Almeida is a rare tree in the family Ebenaceae. The species is native to South America, while having been introduced to Florida and Texas (USA), India, Java and Madagascar. Additionally, this species is distributed in Guangdong Province and the southwest portion of Hainan Province, China. Here, we report and characterize the complete plastome of a cultivar of D. nigra. The length of the complete plastome is 157,168 bp, including 131 genes consisting of 84 protein-coding genes, 37 tRNA genes and 8 rRNA genes. The plastome has the typical structure and gene content of angiosperms, including two inverted repeat (IR) regions of 26,095 bp, a large single copy (LSC) region of 86,610 bp and a small single-copy (SSC) region of 18,386 bp. The total G/C content of the plastome in D. nigra is 37.4%. The complete plastome sequence of D. nigra will make contributions to the conservation genetics of the species, as well as to phylogenetic studies in Ebenaceae.
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Pore architecture in bioceramic scaffolds plays an important role in facilitating vascularization efficiency during bone repair or orbital reconstruction. Many investigations have explored this relationship but lack integrating pore architectural features in a scaffold, hindering optimization of architectural parameters (geometry, size and curvature) to improve vascularization and consequently clinical outcomes. To address this challenge, we have developed an integrating design strategy to fabricate different pore architectures (cube, gyroid and hexagon) with different pore dimensions (â¼350, 500 and 650 µm) in the silicate-based bioceramic scaffolds via digital light processing technique. The sintered scaffolds maintained high-fidelity pore architectures similar to the printing model. The hexagon- and gyroid-pore scaffolds exhibited the highest and lowest compressive strength (from 15 to 55 MPa), respectively, but the cube-pore scaffolds showed appreciable elastic modulus. Moreover, the gyroid-pore architecture contributed on a faster ion dissolution and mass decay in vitro. It is interesting that both µCT and histological analyses indicate vascularization efficiency was challenged even in the 650-µm pore region of hexagon-pore scaffolds within 2 weeks in rabbit models, but the gyroid-pore constructs indicated appreciable blood vessel networks even in the 350-µm pore region at 2 weeks and high-density blood vessels were uniformly invaded in the 500- and 650-µm pore at 4 weeks. Angiogenesis was facilitated in the cube-pore scaffolds in comparison with the hexagon-pore ones within 4 weeks. These studies demonstrate that the continuous pore wall curvature feature in gyroid-pore architecture is an important implication for biodegradation, vascular cell migration and vessel ingrowth in porous bioceramic scaffolds.
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The complete plastome of G. subelliptica, Merr. 1909. The complete length is 158,356 bp, with the typical structure and gene content of angiosperm plastomes, including a large single-copy region (LSC) of 86,220 bp, a repeat region (IRB), and a reverse repeat region (IRA) of 27,399 bp, respectively, and a small single-copy region (SSC) of 17,338 bp. The plastome contains 130 genes, including 85 protein-coding genes, 37 tRNA genes, and 8 rRNA genes. The total G/C content of the plastome is 36.1%.
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Here, we report and characterize the complete plastome of Reevesia pycnantha, Y. Ling 1951, which is a rare tree in the plant family Malvaceae. It is distributed in central and southern Jiangxi, Fujian, Guangdong, Hunan, and other provinces of China, where it is endemic. It grows in subtropical climates at middle and low altitudes of 200-800 meters within valleys, along mountain foothills, or on hillsides, in evergreen broad-leaved forests or at forest edges. Our results show that the length of the complete plastome is 161,964 bp, including 129 genes consisted of 81 protein-coding genes, 37 tRNA genes and 8 rRNA genes. It exhibits the typical quadripartite structure and gene content of angiosperms plastomes and comprises two inverted repeat (IRS) regions of 2,469 bp, a large single copy (LSC) region of 90,657 bp, and a small single-copy (SSC) region of 20,315 bp. The total G/C content in the plastome of R. pycnantha,Y. Ling 1951 is 36.8%. The complete plastome sequence of R. pycnantha, Y. Ling 1951will make contributions to the conservation genetics of this species as well as to phylogenetic studies in Malvaceae.
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Citrus australasica (F. Muell.) Swingle belongs to the family Rutaceae. Citrus australasica is native to eastern Australia and southeastern New Guinea, and is mainly concentrated in a small region of northern New South Wales and tropical rainforest areas in southern Queensland. The complete plastome length of C. australasica is 160,335 bp, with the typical structure and gene content of angiosperm plastids, including a 26,592 bp repeat B (IRB) region, 26,952 bp IRA, 87,678 bp large single copy (LSC) region and 18,756 bp small single copy (SSC) region. The plastid contains 135 genes, including 89 protein-coding genes, 37 tRNA genes, and 8 rRNA genes. The total G/C content of the C. australasica plastome is 38.4%. The complete plastome sequence of C. australasica will provide useful resources for conservation genetics research of this species and phylogenetic research of Rutaceae.
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Cancer cells exploit CD47 overexpression to inhibit phagocytic elimination and neoantigen processing via the myeloid CD47-SIRPα axis and thereby indirectly evade adaptive T cell immunity. Here, we report on a hitherto unrecognized direct immunoinhibitory feature of cancer cell-expressed CD47. We uncovered that in response to IFNγ released during cognate T cell immune attack, cancer cells dynamically enhance CD47 cell surface expression, which coincides with acquiring adaptive immune resistance toward pro-apoptotic effector T cell mechanisms. Indeed, CRISPR/Cas9-mediated CD47-knockout rendered cancer cells more sensitive to cognate T cell immune attack. Subsequently, we developed a cancer-directed strategy to selectively overcome CD47-mediated adaptive immune resistance using bispecific antibody (bsAb) CD47xEGFR-IgG2s that was engineered to induce rapid and prolonged cancer cell surface displacement of CD47 by internalization. Treatment of CD47pos cancer cells with bsAb CD47xEGFR-IgG2s potently enhanced susceptibility to cognate CD8pos T cells. Targeting CD47-mediated adaptive immune resistance may open up new avenues in cancer immunotherapy.
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Anticorpos Biespecíficos , Neoplasias , Antígeno CD47/genética , Humanos , Imunoterapia , Linfócitos TRESUMO
Lannea coromandelica (Houtt.) Merr. is a deciduous tree in the family Anacardiaceae, which grows in lowland and hill forests; 100-1800 m. SW Guangdong, S Guangxi, S Yunnan [Bhutan, India, Myanmar, Nepal, Sri Lanka; cultivated elsewhere in continental SE Asia, such as in Cambodia, Laos, Malaysia, Thailand, Vietnam, where it is probably naturalized]. The length of the complete plastome is 162,460 bp, including 130 genes consisting of 85 protein-coding genes, 37 tRNA genes and 8 rRNA genes. The assembled plastome has the typical structure and gene content of angiosperms plastome, which includes two inverted repeats (IRs) regions of 26,877 bp, a large single copy (LSC) region of 89,599 bp and a small single-copy (SSC) region of 19,107 bp. The total G/C content in the plastome of L. coromandelica is 37.7%. The complete plastome sequence of L. coromandelica will provide contributions to the conservation genetics of this species as well as to phylogenetic studies in Anacardiaceae.
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Tumor-derived exosomes, containing multiple nucleic acids and proteins, have been implicated to participate in the interaction between tumor cells and microenvironment. However, the functional involvement of phosphatases in tumor-derived exosomes is not fully understood. We and others previously demonstrated that protein tyrosine phosphatase receptor type O (PTPRO) acts as a tumor suppressor in multiple cancer types. In addition, its role in tumor immune microenvironment remains elusive. Bioinformatical analyses revealed that PTPRO was closely associated with immune infiltration, and positively correlated to M1-like macrophages, but negatively correlated to M2-like macrophages in breast cancer tissues. Co-cultured with PTPRO-overexpressing breast cancer cells increased the proportion of M1-like tumor-associated macrophages (TAMs) while decreased that of M2-like TAMs. Further, we observed that tumor-derived exosomal PTPRO induced M1-like macrophage polarization, and regulated the corresponding functional phenotypes. Moreover, tumor cell-derived exosomal PTPRO inhibited breast cancer cell invasion and migration, and inactivated STAT signaling in macrophages. Our data suggested that exosomal PTPRO inhibited breast cancer invasion and migration by modulating macrophage polarization. Anti-tumoral effect of exosomal PTPRO was mediated by inactivating STAT family in macrophages. These findings highlight a novel mechanism of tumor invasion regulated by tumor-derived exosomal tyrosine phosphatase, which is of translational potential for the therapeutic strategy against breast cancer.
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Calcified cartilage is a mineralized osteochondral interface region between the hyaline cartilage and subchondral bone. There are few reported artificial biomaterials that could offer bioactivities for substantial reconstruction of calcified cartilage. Herein we developed new poly(L-lactide-co-caprolactone) (PLCL)-based trilayered fibrous membranes as a functional interface for calcified cartilage reconstruction and superficial cartilage restoration. The trilayered membranes were prepared by the electrospinning technique, and the fibrous morphology was maintained when the chondroitin sulfate (CS) or bioactive glass (BG) particles were introduced in the upper or bottom layer, respectively. Although 30% BG in the bottom layer led to a significant decrease in tensile resistance, the inorganic ion release was remarkably higher than that in the counterpart with 10% BG. The in vivo studies showed that the fibrous membranes as osteochondral interfaces exhibited different biological performances on superficial cartilage restoration and calcified cartilage reconstruction. All of the implanted host hyaline cartilage enabled a self-healing process and an increase in the BG content in the membranes was desirable for promoting the repair of the calcified cartilage with time. The histological staining confirmed the osteochondral interface in the 30% BG bottom membrane maintained appreciable calcified cartilage repair after 12 weeks. These findings demonstrated that such an integrated artificial osteochondral interface containing appropriate bioactive ions are potentially applicable for osteochondral interface tissue engineering.
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Calcificação Fisiológica/fisiologia , Membranas Artificiais , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/uso terapêutico , Doenças Ósseas/terapia , Cartilagem/diagnóstico por imagem , Cartilagem/patologia , Sulfatos de Condroitina/química , Modelos Animais de Doenças , Vidro/química , Poliésteres/química , Próteses e Implantes , Coelhos , Resistência à Tração , Microtomografia por Raio-XRESUMO
Tumor-derived extracellular vesicles (EVs) carry potent immunosuppressive factors that affect the antitumor activities of immune cells. A significant part of the immunoinhibitory activity of EVs is attributable to CD73, a GPI-anchored ecto-5'-nucleotidase involved in the conversion of tumor-derived proinflammatory extracellular ATP (eATP) to immunosuppressive adenosine (ADO). The CD73-antagonist antibody oleclumab inhibits cell surface-exposed CD73 and is currently undergoing clinical testing for cancer immunotherapy. However, a strategy to selectively inhibit CD73 exposed on EVs is not available. Here, we present a novel bispecific antibody (bsAb) CD73xEpCAM designed to bind with high affinity the common EV surface marker EpCAM and concurrently inhibit CD73. Unlike oleclumab, bsAb CD73xEpCAM potently inhibited the immunosuppressive activity of EVs from CD73pos/EpCAMpos carcinoma cell lines and patient-derived colorectal cancer cells. Taken together, selective blockade of EV-exposed CD73 by bsAb CD73xEpCAM may be useful as an alternate or complementary targeted approach in cancer immunotherapy.
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Bridelia tomentosa is a deciduous shrub in the family of Phyllanthaceae. It grows in the evergreen primary or secondary thickets or forests in the sea level from 1000 to 1500 m. It distributed in.south China (e.g., Fujian, Guangdong, Guangxi, Hainan etc) and other south Asian countries (e.g. Bangladesh, Bhutan, Cambodia etc). Here, we report and characterize the complete plastome of B. tomentosa. The complete plastome is of 149,958 bp in length with a typical structure and gene content of angiosperm plastome, including two inverted repeat (IRs) regions of 26,354 bp, a large single-copy (LSC) region of 81,355 bp and a small single-copy (SSC) region of 15,895 bp. The plastome contains 129 genes, consisting of 84 protein-coding genes, 37 tRNA genes, eight rRNA genes. The overall G/C content in the plastome of B. tomentosa is 36.0%. The complete plastome sequence of B. tomentosa will provide a useful resource for the conservation genetics of this species as well as for phylogenetic studies in Phyllanthaceae.