Interaction Of Different Cells Research Articles

Inflammatory and differentiation cellular response to calcium silicate cements: An in vitro study.

Inflammatory-regenerative cell interaction is believed to mediate hard tissue formation. This study aimed to investigate the interaction between human inflammatory monocytes with human regenerative fibroblasts after exposure to different calcium silicate materials. Human monocytes were cultured on three materials, polystyrene (PS), mineral trioxide aggregates (MTA) and biodentine (BD), in the presence or absence of lipopolysaccharide (LPS). Half of the monocyte-conditioned media (MoCM) of each group was used to analyse inflammatory cytokine secretion, namely TNF-α, IL-1β, IL-1RA and IL-6. The remaining MoCM was used to culture recipient fibroblasts, measuring the cell number (proliferation) and levels of alkaline phosphatase (differentiation) and lactic acid dehydrogenase (cytotoxicity). In absence of LPS, MTA was associated with higher secretion of TNF-α and lower secretion of IL-1β, while BD triggered higher secretions of both cytokines when both materials were compared to control (PS). When LPS was added, higher levels of all analysed cytokines were observed in the PS and BD groups, whereas for the MTA group, only TNF-α and IL-6 were increased. Fibroblasts responded differently to the MoCM from the different groups, revealing significant increases in proliferation and differentiation capacities, particularly when cultured in CM from monocytes exposed to MTA. The morphological evaluation revealed different patterns of fibroblast shape and spread in the different MoCM groups. Calcium silicate materials modulate the monocyte inflammatory response, which subsequently induce differential effects on the recipient fibroblasts. MTA appears to promote the secretion of prodifferentiation signals from the monocytes, which are received by fibroblasts, promoting their proliferation and differentiation. The model represents a promising tool to evaluate the interaction of different cells in response to different materials.

The effects of mechanical instability on PDGF mediated inflammatory response at early stage of fracture healing under diabetic condition

Background and ObjectiveMechanical stability plays an important role in fracture healing process. Excessive interfragmentary movement will continuously damage the tissue and newly formed capillaries at the fracture site, which leads to overproduction of platelet-derived growth factor (PDGF) that attracts more macrophages into fracture callus, ultimately persistent and enhanced inflammatory response happens. For diabetic condition, the impact of mechanical instability of fracture site on inflammatory response could be further compliciated and the relevant research in this field is relatively limited. MethodsBuilding on previous experimental studies, this study presents a numerical model consisting of a system of reactive-transport equations representing the transport as well as interactions of different cells and cytokines within the fracture callus. The model is initially validated by available experimental data, and then implemented to investigate the role of mechanical stability of fracture site in inflammatory response during early stage of healing. It is assumed that there is an increased release of PDGF due to the rupture of blood vessels resulting from mechanical instability, which leads to increased production of inflammatory cytokines (i.e., TNF-α). The bone healing process under three different conditions were investigated, i.e., mechanically stable condition with normal inflammatory response (Control, Case 1), mechanically unstable condition with normal inflammatory response (Case 2) and mechanically unstable condition with diabetes (Case 3). ResultsMechanical instability can promote the macrophage infiltration and thus induce an enhanced and prolonged inflammatory response, which could impede the MSCs proliferation during the early fracture healing stage (e.g., compared with the control condition, the MSCs concentration in unstable fracture with normal inflammatory response can be reduced by 3.2% and 5.2% on day 2 and day 10 post-fracture, respectively). Under diabetic condition, the mechanical instability of fracture site could lead to a significant increase of TNF-α concentration in fracture callus (Case 3) in comparison to control (Case 1) (e.g., three-fold increase in TNF-α concentration compared to control). In addition, the results show that the mechanical instability affects the cell differentiation and proliferation in fracture callus in a spatially dependent manner, e.g., for diabetic fracture patients, the mechanical instability could potentially decrease the concentration of MSCs, osteoblasts and chondrocytes by around 39%, 30% and 29% in cortical callus, respectively, in comparison to control. ConclusionThe mechanical instability together with diabetic condition can significantly affect the natural resolution of inflammation during early stage of healing by turning acute inflammation into chronic inflammation which is characterized by a continuously upregulated TNF-α pathway.

Hierarchical Membranes Self‐Assembled at the Interface between Peptides and Polymer Aqueous Solutions

AbstractBiocompatible and biodegradable molecules capable of spontaneous self‐assembly into hierarchical structures have the potential to serve as building blocks for complex scaffolds for cell culture. These scaffolds are meant to mimic the natural environment required for successful cell growth. Thus, they must be precisely designed and present specific mechanical and structural properties along with required biological and chemical cues. Combining the hierarchical structure and chemical functionality of a peptide with the stability of a polymer has led to the formation of complex and stable biomaterials. Among these hybrid biomaterials, macroscopic membranes self‐assembled at the aqueous interface between self‐assembling peptides and polymer solutions have gained attention over the past decade. The goal of this mini‐review is to highlight the advantages and challenges of utilizing polymer/peptide self‐assembled macroscopic membranes toward the development of novel platforms for the study of the interaction of different cells with their environment. As most of the membranes features are determined as soon as they assemble, this review begins with a detailed description of the membranes formation mechanism, which evolved and developed over the years. The variety of membranes formed using different peptides and polymers is then described, with special focus placed on their unique structure. Then the bio‐functions of the membranes and their emerging potential for bio‐applications are presented. In the final section, the shortcomings preventing an extended use of these membranes as well as their future prospects, are discussed. This mini‐review aims to give light to an emerging niche of biomaterials capable of forming hierarchical structures utilizing natural building blocks and the naturally occurring process of self‐assembly, providing an innovative approach for creating scaffolds that mimic the natural extracellular environment.

Cancer resistance to immunotherapy: What is the role of cancer stem cells?

Immunotherapy is an emerging form of cancer therapy that is associated with promising outcomes. However, most cancer patients either do not respond to immunotherapy or develop resistance to treatment. The resistance to immunotherapy is poorly understood compared to chemotherapy and radiotherapy. Since immunotherapy targets cells within the tumor microenvironment, understanding the behavior and interactions of different cells within that environment is essential to adequately understand both therapy options and therapy resistance. This review focuses on reviewing and analyzing the special features of cancer stem cells (CSCs), which we believe may contribute to cancer resistance to immunotherapy. The mechanisms are classified into three main categories: mechanisms related to surface markers which are differentially expressed on CSCs and help CSCs escape from immune surveillance and immune cells killing; mechanisms related to CSC-released cytokines which can recruit immune cells and tame hostile immune responses; and mechanisms related to CSC metabolites which modulate the activities of infiltrated immune cells in the tumor microenvironment. This review also discusses progress made in targeting CSCs with immunotherapy and the prospect of developing novel cancer therapies.

Comparative effects of capsaicin in chronic obstructive pulmonary disease and asthma (Review).

Chronic obstructive pulmonary disease (COPD) and asthma are chronic respiratory diseases with high prevalence and mortality that significantly alter the quality of life in affected patients. While the cellular and molecular mechanisms engaged in the development and evolution of these two conditions are different, COPD and asthma share a wide array of symptoms and clinical signs that may impede differential diagnosis. However, the distinct signaling pathways regulating cough and airway hyperresponsiveness employ the interaction of different cells, molecules, and receptors. Transient receptor potential cation channel subfamily V member 1 (TRPV1) plays a major role in cough and airway inflammation. Consequently, its agonist, capsaicin, is of substantial interest in exploring the cellular effects and regulatory pathways that mediate these respiratory conditions. Increasingly more studies emphasize the use of capsaicin for the inhalation cough challenge, yet the involvement of TRPV1 in cough, bronchoconstriction, and the initiation of inflammation has not been entirely revealed. This review outlines a comparative perspective on the effects of capsaicin and its receptor in the pathophysiology of COPD and asthma, underlying the complex entanglement of molecular signals that bridge the alteration of cellular function with the multitude of clinical effects.

A wild-derived inbred mouse strain, MSM/Ms, provides insights into novel skin tumor susceptibility genes.

Cancer is one of the most catastrophic human genetic diseases. Experimental animal cancer models are essential for gaining insights into the complex interactions of different cells and genes in tumor initiation, promotion, and progression. Mouse models have been extensively used to analyze the genetic basis of cancer susceptibility. They have led to the identification of multiple loci that confer, either alone or in specific combinations, an increased susceptibility to cancer, some of which have direct translatability to human cancer. Additionally, wild-derived inbred mouse strains are an advantageous reservoir of novel genetic polymorphisms of cancer susceptibility genes, because of the evolutionary divergence between wild and classical inbred strains. Here, we review mapped Stmm (skin tumor modifier of MSM) loci using a Japanese wild-derived inbred mouse strain, MSM/Ms, and describe recent advances in our knowledge of the genes responsible for Stmm loci in the 7,12-dimethylbenz(a)anthracene (DMBA)/12-O-tetradecanoylphorbol-13-acetate (TPA) two-stage skin carcinogenesis model.

Single-cell transcriptomics of murine mural cells reveals cellular heterogeneity.

Mural cells (MCs) wrap around the endothelium, and participate in the development and homeostasis of vasculature. MCs have been reported as heterogeneous population morphologically and functionally. However, the transcriptional heterogeneity of MCs was rarely studied. In this study, we illustrated the transcriptional heterogeneity of MCs with different perspectives by using publicly available single-cell dataset GSE109774. Specifically, MCs are transcriptionally different from other cell types, and ligand-receptor interactions of different cells with MCs vary. Re-clustering of MCs identified five distinct subclusters. The heterogeneity of MCs in tissues was reflected by MC coverage, various distribution of MC subclusters, and ligand-receptor interactions of MCs and parenchymal cells. The transcriptomic diversity of MCs revealed in this article will help facilitate further research into MCs.Electronic Supplementary MaterialSupplementary material is available for this article at 10.1007/s11427-020-1823-2 and is accessible for authorized users.

AB011. Surgical management of myasthenia gravis

: Since Ferdinand Sauerbruch performed a subtotal thyroidectomy with concomitant subtotal thymectomy with a subsequent clinical improvement of myasthenia gravis (MG) in 1912, surgeons try to improve the approaches, extend and strategy of thymectomies. The effector mechanism of MG are autoantibodies which target the neuro-muscular junction. In the 1970s the detection of acetylcholine receptor antibodies supported the theory of an autoimmune disease. In the 2000s the muscle specific kinase was identified as an additional autoantibody. Just recently low-density lipo-protein receptor related protein 4 (LRP4) was postulated to be a potential autoantibody target. The interaction of these antibodies leads to numerous effects on the transmission of the electric signal from the nerve to the muscle cells with a complex interaction of different cells of the immune response originating from the thymus gland. These interactions are evident in non thymomatous MG as well as MG with thymoma. In latter, additional paraneoplastic mechanism are discussed. Interestingly, the incidence of MG is highest in AB and B2 thymoma patients, of whom about one quarter suffer from paraneoplastic MG. Whereas the indication for thymectomy is clear in cases of thymoma plus MG, the indication for thymectomy for non-thymomatous MG remains in parts controversial. Up to 2016 the evidence base for this indication was as low as level III. In 2016 Wolfe et al. published a first of its kind land mark RCT on thymectomy in MG. Although methodology was controversial in some areas it was the first RCT to show the positive effects of this procedure in MG. The primary outcomes were the time-weighted average quantitative Myasthenia Gravis score over a 3-year period and the time-weighted average required dose of prednisone over a 3-year period. In a follow up publication, the study group could show a continuous benefit in a 5-year follow up. The findings of these RCTs support the conclusion of many other non-randomized trial or retrospective analysis. Nevertheless, many aspects of modern thymic surgery proclaimed remain unclear and need further high-level evidence. This includes the surgical approach and the extent of resection, as well as the definition of the patient cohort benefiting the most from the procedure. Although the Wolfe study investigates only open transsternal approaches, with a patient recruitment period of 2006 to 2012, many surgeons believe that the modern minimal invasive approaches are at least equal in the treatment effect with fewer complications. These minimal invasive approaches include extended transcervical approaches, video-assisted thoracoscopic surgery (VATS) approaches either in a classic fashion transintercostal or subxiphoid as well as robotic approaches. All these approaches proved feasible and safe in expert hands but failed to show superiority in a board use. The extend of the resection in the study was defined as en bloc resection of all mediastinal tissue that could anatomically contain gross or microscopic thymus (or both). In many publications this kind of a resection is called an extended thymectomy although the terms thymectomy and extended thymectomy are used inconsistently throughout the literature. Many surgeons believe that the removal of all mediastinal tissue is indicated, since many studies showed ectopic thymic tissue outside the distinct gland and spread in mediastinal fat. But there is no level II or higher evidence supporting this. A higher incidence of phrenic nerve injuries with consecutive diaphragmatic paralysis might be associated with this extended resection, resulting in serve pulmonary complication in MG patients, as well as other rare but major complications like vessel injuries. Regarding the patient cohort suitable for surgical treatment the Wolfe study included patients with a disease onset of less than 3 years, an age of 18 to 60 years, a serum acetylcholine-receptor-antibody level of more than 1.00 nmol per liter (elevated levels of 0.50 to 0.99 nmol per liter were accepted if the diagnosis was confirmed by a positive edrophonium test, abnormal repetitive nerve stimulation, or abnormal single-fiber electromyography), and a Myasthenia Gravis Foundation of America clinical classification of II to IV. Participants could be taking appropriate anticholinesterase therapy with or without oral glucocorticoids. Exclusion criteria were thymoma on computed tomography or magnetic resonance imaging of the chest. All these criteria go inline with the guidelines for this disease prior to the study and have not changed since then. Again, only weak evidence supports the criteria. We conclude on the basis of available evidence that surgery for MG is beneficial for sero-positive patient between 18–60 years with a short duration of the disease. In the daily practice of the authors the robotic extended thymectomy is used routinely. In addition, we offer this operation to AChR-sero-negative patients after an in-depth informed consent process.

Development of a 3D matrix for modeling mammalian spinal cord injury in vitro.

Spinal cord injury affects millions of people around the world, however, limited therapies are available to improve the quality of life of these patients. Spinal cord injury is usually modeled in rats and mice using contusion or complete transection models and this has led to a deeper understanding of the molecular and cellular complexities of the injury. However, it has not to date led to development of successful novel therapies, this is in part due to the complexity of the injury and the difficulty of deciphering the exact roles and interactions of different cells within this complex environment. Here we developed a collagen matrix that can be molded into the 3D tubular shape with a lumen and can hence support cell interactions in a similar architecture to a spinal cord. We show that astrocytes can be successfully grown on this matrix in vitro and when injured, the cells respond as they do in vivo and undergo reactive gliosis, one of the steps that lead to formation of a glial scar, the main barrier to spinal cord regeneration. In the future, this system can be used to quickly assess the effect of drugs on glial scar protein activity or to perform live imaging of labeled cells after exposure to drugs.

Efficient cell pairing in droplets using dual-color sorting.

The use of microfluidic droplets has become a powerful tool for the screening and manipulation of cells. However, currently this is restricted to assays involving a single cell type. Studies on the interaction of different cells (e.g. in immunology) as well as the screening of antibody-secreting cells in assays requiring an additional reporter cell, have not yet been successfully demonstrated. Based on Poisson statistics, the probability for the generation of droplets hosting exactly one cell of two different types is just 13.5%. To overcome this limitation, we have developed an approach in which different cell types are stained with different fluorescent dyes. Subsequent to encapsulation into droplets, the resulting emulsion is injected into a very compact sorting device allowing for analysis at high magnification and fixation of the cells close to the focal plane. By applying dual-color sorting, this furthermore enables the specific collection and analysis of droplets with exactly two different cells. Our approach shows an efficiency of up to 86.7% (more than 97% when also considering droplets hosting one or more cells of each type), and, hence, should pave the way for a variety of cell-based assays in droplets.

The interactions of astrocytes and fibroblasts with defined pore structures in static and perfusion cultures

Open pores to maintain nutrient diffusion and waste removal after cell colonization are crucial for the successful application of constructs based on assembled membranes, in our case tubular scaffolds made of ɛ-polycaprolactone (PCL), for use in tissue engineering. Due to the complex three-dimensional structure and large size of such scaffolds needed for transplantable tissues, it is difficult to investigate the cell–pore interactions in situ. Therefore miniaturized bioreactors inside Petri dishes (30 mm in diameter), containing porous PCL or poly-dimethylsiloxane (PDMS) membranes, were developed to allow the interactions of different cells with defined pores to be investigated in situ during both static and perfusion cultures. Investigation of two different cell types (fibroblasts and cortical astrocytes) and how they interact with a range of pores (100–350 μm in diameter) for up to 50 days indicated that the cells either ‘covered’ or ‘bridged’ the pores. Three distinct behaviors were observed in the way cortical astrocytes interacted with pores, while fibroblasts were able to quickly bridge the pores based on consistent “joint efforts”. Our studies demonstrate that the distinct pore sealing behaviors of both cell types were influenced by pore size, initial cell density and culture period, but not by medium perfusion within the range of shear forces investigated. These findings form important basic data about the usability of pores within scaffolds that could inform the design and fabrication of suitable scaffolds for various applications in tissue engineering.

Status und Zukunft des nichtinvasiven Zell-Trackings

The interaction of different cells is an important regulator in the development of many diseases, including cancer. Some cells are recruited directly from the local tissue environment, others reach the pathological focus via the circulation. Using non invasive cell tracking methods, the distribution and migration of labeled cells can be studied in experimental animal models, and the role of these cells on the pathogenesis of disease can thus be elucidated. Scintigraphy and SPECT, and especially MRI and optical imaging, are frequently used for this purpose. Studies are mostly performed with macrophages and granulocytes (inflammatory cells), which accumulate in nephritis, encephalitis, and tumors. At present, the understanding of progenitor cell migration and differentiation is gaining increasing interest in neurological disorders (for example Parkinson's disease) and in cardiac diseases (for example myocardial infarction).Non invasive cell tracking is already established in basic research; in the future, a clinical application of cell tracking is foreseeable in the framework of cell therapy.

Analysis of T cell activation pathways in patients with liver cirrhosis, impaired delayed hypersensitivity and other T cell-dependent functions.

Patients with cirrhosis of the liver frequently demonstrate anergy in intracutaneous tests and fail to respond to vaccination, suggesting impaired delayed hypersensitivity and other T cell-dependent functions in vivo. T cell activation through the coordinated interaction of different cells of the immune system (B cell, antigen-presenting cells (APC)) is an important step in the induction of cellular and humoral immune responses. Impaired T cell-dependent functions in patients with liver cirrhosis may thus be explained by defective T cell activation. We prospectively investigated T cell activation pathways in 12 patients (nine males, three females) with alcoholic liver cirrhosis (seven Child Pugh stage A and B (CP A + B), five Child Pugh stage C (CP C)) and five healthy controls and compared the in vitro results of T cell activation with data obtained in vivo, e.g. intracutaneous tests and vaccination against hepatitis B surface antigen (HBs-Ag). Five out of eight patients who completed vaccination against hepatitis B virus infection were non-responders; one of the three responders had a non-protective anti-HBs titre. Moreover, three of five patients with alcoholic liver cirrhosis CP A + B, and two out of three with CP C were anergic in intracutaneous tests to a set of diverse antigens. All parameters of T cell activation were normal, including proliferation mediated by CD2, CD3-T cell receptor (TCR) complex, and CD28; acquisition of responsiveness to exogenous IL-2 and IL-4; activation of proteinkinase C (PKC) by phorbol ester and calcium influx by addition of ionomycin. The ability of monocytes to deliver costimulatory signals was preserved in patients with alcoholic cirrhosis. In addition, serum of patients with alcoholic liver disease did not inhibit T cell proliferation. We conclude that, although in patients with alcoholic liver cirrhosis T cell-dependent functions are impaired in vivo, T cell activation pathways are not responsible for the observed immune defect.

Arnebin-1 Accelerates Normal and Hydrocortisone-Induced Impaired Wound Healing

Wound healing involves inflammation, cell proliferation, matrix deposition, and tissue remodeling. Interaction of different cells, extracellular matrix proteins, and their receptors are mediated by cytokines and growth factors during wound healing. In this study, we have evaluated the effect of arnebin-1, a natural product isolated from Arnebia nobilis, on normal and impaired wound healing in cutaneous punch wound model. Arnebin-1 was applied topically daily on wounds of hydrocortisone-treated or untreated animals. Arnebin-1 significantly accelerated healing of wounds with or without hydrocortisone treatment as revealed by a reduction in the wound width and gap length compared with controls. Arnebin-1 treatment promoted the cell proliferation, migration, and vessel formation to form a thick granulation tissue and re-epithelialization of the wounds. An increase in the synthesis of collagen, fibronectin and transforming growth factor-beta1 was seen in arnebin-1-treated wounds compared with the untreated control. As transforming growth factor-beta1 is known to enhance wound healing, and associated with the wound healing defect in hydrocortisone-treated wounds, the enhanced expression of transforming growth factor-beta1 at both translational and transcriptional level by arnebin-1 may be responsible for the enhancement of wound healing during normal and impaired wound repair. These studies suggest that arnebin-1 could be developed as a potent therapeutic agent for wound healing in steroid-impaired wounds.

Curcumin enhances wound healing in streptozotocin induced diabetic rats and genetically diabetic mice.

Tissue repair and wound healing are complex processes that involve inflammation, granulation and tissue remodeling. Interactions of different cells, extracellular matrix proteins and their receptors are involved in wound healing, and are mediated by cytokines and growth factors. Previous studies from our laboratory have shown that curcumin (diferuloylmethane), a natural product obtained from the rhizomes of Curcuma longa, enhanced cutaneous wound healing in rats and guinea pigs. In this study, we have evaluated the efficacy of curcumin treatment by oral and topical applications on impaired wound healing in diabetic rats and genetically diabetic mice using a full thickness cutaneous punch wound model. Wounds of animals treated with curcumin showed earlier re-epithelialization, improved neovascularization, increased migration of various cells including dermal myofibroblasts, fibroblasts, and macrophages into the wound bed, and a higher collagen content. Immunohistochemical localization showed an increase in transforming growth factor-beta1 in curcumin-treated wounds compared to controls. Enhanced transforming growth factor-beta1 mRNA expression in treated wounds was confirmed by in situ hybridization, and laser scan cytometry. A delay in the apoptosis patterns was seen in diabetic wounds compared to curcumin treated wounds as shown by terminal deoxynucleotidyl transferase-mediated deoxyuridyl triphosphate nick end labeling analysis. Curcumin was effective both orally and topically. These results show that curcumin enhanced wound repair in diabetic impaired healing, and could be developed as a pharmacological agent in such clinical settings.

Competition of contacting heterotypic epithelial sheets for the territory in culture

Co-cultured epithelial cells of various lines formed mixed cohesive sheets. Contact interactions of different cells in the sheets were studied by phase contrast and interference reflection microscopy, time-lapse microcinematography, transmission and scanning electron microscopy. It was found that heterotypic cells in the combined sheets were locked together by the complexes of specialized contacts and were metabolically coupled, as shown by the dye transfer. At the same time heterotypic cells continued to extend pseudopods at the contacting lateral surfaces and to attach these pseudopodies to substratum. Due to competition of pseudopod attachments one group of cells in the sheet often progressively pushed another group, from the substratum. This competition of cells for substratum may provide an important mechanism for morphogenetic reorganisation of epithelial sheets and of other groups of interacting cells in vivo.