Cells Tissues Organs最新文献

The primary cilium is a solitary, sensory organelle with many roles in bone development, maintenance, and function. In the osteogenic cell lineage, including skeletal stem cells, osteoblasts, and osteocytes, the primary cilium plays a vital role in the regulation of bone formation, and this has made it a promising pharmaceutical target to maintain bone health. While the role of the primary cilium in the osteogenic cell lineage has been increasingly characterized, little is known about the potential impact of targeting the cilium in relation to osteoclasts, a hematopoietic cell responsible for bone resorption. The objective of this study was to determine whether osteoclasts have a primary cilium and to investigate whether or not the primary cilium of macrophages, osteoclast precursors, serves a functional role in osteoclast formation. Using immunocytochemistry, we showed the macrophages have a primary cilium, while osteoclasts lack this organelle. Furthermore, we increased macrophage primary cilia incidence and length using fenoldopam mesylate and found that cells undergoing such treatment showed a significant decrease in the expression of osteoclast markers tartrate-resistant acid phosphatase, cathepsin K, and c-Fos, as well as decreased osteoclast formation. This work is the first to show that macrophage primary cilia resorption may be a necessary step for osteoclast differentiation. Since primary cilia and preosteoclasts are responsive to fluid flow, we applied fluid flow at magnitudes present in the bone marrow to differentiating cells and found that osteoclastic gene expression by macrophages was not affected by fluid flow mechanical stimulation, suggesting that the role of the primary cilium in osteoclastogenesis is not a mechanosensory one. The primary cilium has been suggested to play a role in bone formation, and our findings indicate that it may also present a means to regulate bone resorption, presenting a dual benefit of developing ciliary-targeted pharmaceuticals for bone disease.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) first infects the host nasal mucosa, where the viral spike protein binds to angiotensin-converting enzyme 2 (ACE2) on the mucosal cells. This study aimed at searching host cell surface molecules that could contribute to the infection in two views; abundance on host cells and affinity to the spike protein. Since the nasal mucosa is lined by respiratory and olfactory epithelia, and both express an immunoglobulin superfamily member cell adhesion molecule 1 (CADM1), whether CADM1 would participate in the spike protein binding was examined. Immunohistochemistry on the mouse nasal cavity detected CADM1 strongly in the olfactory epithelium at cell-cell contacts and on the apical surface but just faintly in the respiratory epithelium. In contrast, ACE2 was detected in the respiratory, not olfactory, epithelium. When mice were administered intranasally with SARS-CoV-2 S1 spike protein and an anti-CADM1 ectodomain antibody separately, both were detected exclusively on the olfactory, not respiratory, epithelium. Then, the antibody and S1 spike protein were administered intranasally to mice in this order with an interval of 1 h. After 3 h, S1 spike protein was detected as a protein aggregate floating in the nasal cavity. Next, S1 spike protein labeled with fluorescein was added to the monolayer cultures of epithelial cells exogenously expressing ACE2 or CADM1. Quantitative detection of fluorescein bound to the cells revealed that S1 spike protein bound to CADM1 with affinity half as high as to ACE2. Consistently, docking simulation analyses revealed that S1 spike protein could bind to CADM1 three-quarters as strongly as to ACE2 and that the interface of ACE2 was similar in both binding modes. Collectively, intranasal S1 spike protein appeared to prefer to accumulate on the olfactory epithelium, and CADM1 was suggested to contribute to this preference of S1 spike protein based on the molecular abundance and affinity.

It is apparent that whilst many reports are available regarding platelet-rich-plasma (PRP), the larger majority of these have been mainly focussed on autologous sources, and for good reason. Issues relating to allogenic source have been consciously avoided owing to concerns of cross infectivity and immune rejection. However, this topic today is now revisited and is of interest since progress over the year has demonstrated its safety, efficacy, and its abundance of supply. The present systematic review was thus conducted to elucidate advances made in this area, with the aim to provide a wider and deeper understanding of studies relevant to the application of allogenic PRP in cartilage repair. Literature search was conducted systematically using Medline, ProQuest, Web of Science, Cochrane Central Register of Controlled Trials, and snowballing searching strategy to identify relevant studies using topic-specific keywords in various combinations including "allogenic, platelet, rich, plasma" OR "allogeneic, platelet, rich, plasma" OR "allogenic platelet-rich plasma" OR "allogeneic platelet-rich plasma" OR "allogenic platelet rich plasma" OR "allogeneic platelet rich plasma" AND cartilage OR chondrocytes OR synoviocytes OR stem cells. Studies that used allogenic PRP in an attempt to facilitate cartilage repair were included. The risk of bias was assessed by the SYRCLE's checklist. Of 206 studies identified, 12 were found eligible. Only those studies that are clearly related and specific to allogenic PRP were included. Of these, nine investigated the efficacy of allogenic PRP in animal models, while three articles employed an in vitro model. Allogenic PRP promotes cell proliferation, cartilage matrix production, and anti-inflammatory effects in vitro. The in vivo studies reported histological evidence of significant acceleration of cartilage repair in treated animals. Despite several conflicting findings, all studies agreed that allogenic PRP is safe and potentially efficacious for cartilage repair, with the advantages of allogenic sources apparent.

Introduction: The influence of mechanical forces generated by stromal cells in the perivascular matrix is thought to be a key regulator in controlling blood vessel growth. Cadherins are mechanosensors that facilitate and maintain cell-cell interactions and blood vessel integrity, but little is known about how stromal cells regulate cadherin signaling in the vasculature. Our objective was to investigate the relationship between mechanical phenotypes of stromal cells with cadherin expression in 3D tissue engineering models of vascular growth.

Methods: Stromal cell lines were subjected to a bead displacement assay to track matrix distortions and characterize mechanical phenotypes in 3D microtissue models. These cells included human ventricular cardiac (NHCF), dermal (NHDF), lung (NHLF), breast cancer-associated (CAF), and normal breast fibroblasts (NBF). Cells were embedded in a fibrin matrix (10 mg/mL) with fluorescent tracker beads; images were collected every 30 min. We also studied endothelial cells (ECs) in co-culture with mechanically active or inactive stromal cells and quantified N-Cad, OB-Cad, and VE-Cad expression using immunofluorescence.

Results: Bead displacement studies identified mechanically active stromal cells (CAFs, NHCFs, NHDFs) that generate matrix distortions and mechanically inactive cells (NHLFs, NBFs). CAFs, NHCFs, and NHDFs displaced the matrix with an average magnitude of 3.17 ± 0.11 μm, 3.13 ± 0.06 μm, and 2.76 ± 0.05 μm, respectively, while NHLFs and NBFs displaced the matrix with an average of 1.82 ± 0.05 μm and 2.66 ± 0.06 μm in fibrin gels. Compared to ECs only, CAFs + ECs as well as NBFs + ECs in 3D co-culture significantly decreased expression of VE-Cad; in addition, Pearson's Correlation Coefficient for N-Cad and VE-Cad showed a strong correlation (>0.7), suggesting cadherin colocalization. Using a microtissue model, we demonstrated that mechanical phenotypes associated with increased matrix deformations correspond to enhanced angiogenic growth. The results could suggest a mechanism to control tight junction regulation in developing vascular beds for tissue engineering scaffolds or understanding vascular growth during developmental processes.

Conclusion: Our studies provide novel data for how mechanical phenotype of stromal cells in combination with secreted factor profiles is related to cadherin regulation, localization, and vascularization potential in 3D microtissue models.

Introduction: Ocular diseases pose a significant health concern for donkeys. However, studies examining the microanatomy and cell populations of the donkey retina are scarce. The current study aimed to describe the vascular pattern of the donkey retina and document its cellular components.

Methods: The donkey retina specimens were obtained from different retinal regions and prepared for semithin sectioning and immunohistochemistry.

Results: The donkey has a paurangiotic retina in which retinal vessels are confined to a narrow area around the optic disc. Glial cells coexist with the blood vessels being very numerous in the vascular region and become scanty in the avascular ones. S-100-positive astrocytes could be observed in these avascular areas. Ganglion cells are organized in a single layer with the least population existing in the peripheral retina. Acidic fibroblast growth factor (AFGF) is immunoreactive in amacrine and ganglion cells. A subpopulation of amacrine cells reacted strongly to tyrosine hydroxylase (TH), and others reacted positively to S-100 protein. Ganglion cell nuclei exhibited a strong immunoreactivity to S-100 protein as well. Furthermore, glial fibrillary acidic protein (GFAP) is used to identify Müller cells that extend their processes across the retina from the inner to the outer limiting membrane.

Conclusions: In conclusion, our findings provide novel insights into the normal retinal organization. The donkey retina shows the characteristic expression of immunohistochemical markers for the major cell types. In addition, the distribution of glial cells is comparable between the vascular and avascular regions.

Every year, hundreds of thousands of cancer patients receive radiotherapy treatment. Oxidative stress is observed in healthy tissues due to irradiation exposure. The present study is the first to address the effects of Vaccinium myrtillus (whortleberry, WB) against the effects of X-ray irradiation on retinal tissue. Twenty-four Sprague-Dawley rats were randomly allocated into 4 groups: (1) control group: rats without any treatment, (2) X-ray irradiation group: 8 Gray (Gy) RT for 2 days, (3) 100 mg WB extract + X-ray irradiation group: 8 Gy irradiation for 2 days and followed by intraperitoneal (IP) WB extract (100 mg/kg) supplementation for 10 days, (4) 200 mg WB extract + X-ray irradiation group: 8 Gy irradiation for 2 days and followed by IP WB extract (200 mg/kg) supplementation for 10 days. Eyes were enucleated on the 10th day after RT for histopathological, immunohistochemical (8-hydroxy-2'-deoxyguanosine [8-OHdG], endothelial nitric oxide synthase [eNOS]), and biochemical analyses (glutathione peroxidase [GSH], and malondialdehyde [MDA]). The GSH levels significantly decreased and MDA levels and 8-OHdG staining increased after X-ray irradiation compared to the control group. Combined X-ray irradiation + WB treatment significantly increased GSH levels and significantly decreased MDA production and 8-OHdG staining. However, eNOS staining was not affected in any of the groups. Besides, X-ray irradiation significantly increased cell losses and edematous areas. The WB significantly reversed the cellular damage in ganglion cells, inner nuclear, and outer nuclear layers in quantitative analyses. The X-ray irradiation caused significant retinal impairment, and additional WB therapy provided protective effects against radiation-induced retinopathy. These results may suggest WB extract as an adjuvant therapy to reverse retinal impairments after X-ray irradiation.

The vomeronasal organ (VNO) is a tubular pheromone-sensing organ in which the lumen is covered with sensory and non-sensory epithelia. This study used immunohistochemistry and lectin histochemistry techniques to evaluate developmental changes, specifically of the glycoconjugate profile, in the horse VNO epithelium. Immunostaining analysis revealed PGP9.5 expression in some vomeronasal non-sensory epithelium (VNSE) cells and in the vomeronasal receptor cells of the vomeronasal sensory epithelium (VSE) in fetuses, young foals, and adult horses. Olfactory marker protein expression was exclusively localized in receptor cells of the VSE in fetuses, young foals, and adult horses and absent in VNSE. To identify the glycoconjugate type, lectin histochemistry was performed using 21 lectins. Semi-quantitative analysis revealed that the intensities of glycoconjugates labeled with WGA, DSL, LEL, and RCA120 were significantly higher in adult horse VSE than those in foal VSE, whereas the intensities of glycoconjugates labeled with LCA and PSA were significantly lower in adult horse VSE. The intensities of glycoconjugates labeled with s-WGA, WGA, BSL-II, DSL, LEL, STL, ConA, LCA, PSA, DBA, SBA, SJA, RCA120, jacalin, and ECL were significantly higher in adult horse VNSE than those in foal VNSE, whereas the intensity of glycoconjugates labeled with UEA-I was lower in adult horse VNSE. Histochemical analysis of each lectin revealed that various glycoconjugates in the VSE were present in the receptor, supporting, and basal cells of foals and adult horses. A similar pattern of lectin histochemistry was also observed in the VNSE of foals and adult horses. In conclusion, these results suggest that there is an increase in the level of N-acetylglucosamine (labeled by WGA, DSL, LEL) and galactose (labeled by RCA120) in horse VSE during postnatal development, implying that they may influence the function of VNO in adult horses.

Background: Volumetric muscle loss (VML) causes pain and disability in patients who sustain traumatic injury from invasive surgical procedures, vehicle accidents, and battlefield wounds. Clinical treatment of VML injuries is challenging, and although options such as free-flap autologous grafting exist, patients inevitably develop excessive scarring and fatty infiltration, leading to muscle weakness and reduced quality of life.

Summary: New bioengineering approaches, including cell therapy, drug delivery, and biomaterial implantation, have emerged as therapies to restore muscle function and structure to pre-injury levels. Of these, acellular biomaterial implants have attracted wide interest owing to their broad potential design space and high translational potential as medical devices. Implantable biomaterials fill the VML defect and create a conduit that permits the migration of regenerative cells from the intact muscle tissue to the injury site. Invading cells and regenerating myofibers are sensitive to the biomaterial's structural and biochemical properties, which can play instructive roles in guiding cell fate and organization into functional tissue.

Key messages: Many diverse biomaterials have been developed for skeletal muscle regeneration with variations in biophysical and biochemical properties, and while many have been tested in vitro, few have proven their regenerative potential in clinically relevant in vivo models. Here, we provide an overview of recent advances in the design, fabrication, and application of acellular biomaterials made from synthetic or natural materials for the repair of VML defects. We specifically focus on biomaterials with rationally designed structural (i.e., porosity, topography, alignment) and biochemical (i.e., proteins, peptides, growth factors) components, highlighting their regenerative effects in clinically relevant VML models.

Introduction: Neurogenesis in the adult brain may play an important role in memory and cognition; however, knowledge of neurogenic markers in the human brain remains limited. We compared the single-nucleus transcriptome of the hippocampus with that of other cortical regions to identify hippocampus-specific neurogenic markers.

Methods: We analyzed 26,189 nuclei from four human brains collected within 16 h of death. Clustering and annotation were performed to examine differential expression, gene ontology, and intercellular communication. DCX expression was validated by ddPCR.

Results: Immature markers such as DCX, CALB2, NES, SOX2, PAX6, DPYSL3, and TUBB3 were expressed in both hippocampus and prefrontal cortex, with higher levels in the prefrontal cortex. ddPCR confirmed higher expression of DCX in the prefrontal cortex. DCX was involved in both neurogenesis and neuroprotection pathways.

Conclusion: Neurogenic markers are not definitive indicators of adult neurogenesis as their roles are more complex than previously understood.

Introduction: An early substantial loss of basal forebrain cholinergic neurons (BFCNs) is a common property of Alzheimer's disease and the degeneration of functional BFCNs is related to learning and memory deficits. As a biocompatible and conductive scaffold for growth of neural stem cells, three-dimensional graphene foam (3D-GF) supports applications in tissue engineering and regenerative medicine. Although its effects on differentiation have been demonstrated, the effect of 3D-GF scaffold on the generation of BFCNs still remains unknown.

Methods: In this study, we used 3D-GF as a culture substrate for neural progenitor cells (NPCs) and demonstrated that this scaffold material promotes the differentiation of BFCNs while maintaining excellent cell viability and proliferation.

Results: Immunofluorescence analysis, real-time polymerase chain reaction, Western blotting, and ELISA revealed that the proportion of BFCNs at 21 days of differentiation reached approximately 30.5% on 3D-GF compared with TCPS group that only presented 9.7%. Furthermore, a cell adhesion study suggested that 3D-GF scaffold enhances the expression of adhesion proteins including vinculin, integrin, and N-cadherin. These findings indicate that 3D-GF scaffold materials are preferable candidates for the differentiation of BFCNs from NPCs.

Conclusions: These results suggest new opportunities for the application of 3D-GF scaffold as a neural scaffold for cholinergic neurons therapies based on NPCs.