The NLRP3 Inflammasome Transmits Sterile Inflammation Signals to Sustain Proper Mitochondrial Electron Transport Chain Function and Influences Cellular Metabolism.

The Nlrp3 inflammasome is a pattern recognition receptor (PRR) and an important component of innate immunity, located in the cytoplasm of various cell types, including those derived from hematopoietic lineages. It is highly expressed in hematopoietic stem/progenitor cells (HSPCs) and in the cells that constitute the bone marrow (BM) hematopoietic microenvironment. The Nlrp3 inflammasome plays a role in several biological processes depending on the level of activation.

Optimizing single cell RNA sequencing of stem cells. A streamlined workflow for enhanced sensitivity and reproducibility in hematopoietic studies. The use of human umbilical cord blood-derived hematopoietic stem and progenitor cells.

Background: Human hematopoietic stem/progenitor cells (HSPCs) are enriched in umbilical cord blood (UCB) among cell populations that express CD34 and CD133 (PROM1) antigens. These cells can be purified further and sorted by FACS as CD34LinCD45 and CD133LinCD45 cells. It has been postulated that the population of CD133 HSPCs is enriched for more primitive stem cells.

Complosome as a new intracellular regulatory network in both normal and malignant hematopoiesis.

Hematopoietic cells and lymphocytes arise from a common stem cell for both lineages. This explains why similar signaling networks regulate the development and biological functions of these cells. One crucial regulatory mechanism involves interactions with soluble mediators of innate immunity, including activated elements of the complement cascade (ComC).

Expression of innate immunity genes in human hematopoietic stem/progenitor cells - single cell RNA-seq analysis.

Background: The complement system expressed intracellularly and known as complosome has been indicated as a trigger in the regulation of lymphocyte functioning. The expression of its genes was confirmed also in several types of human bone marrow-derived stem cells: mononuclear cells (MNCs), very small embryonic-like stem cells (VSELs), hematopoietic stem/progenitor cells (HSPCs), endothelial progenitors (EPCs) and mesenchymal stem cells (MSCs). In our previous studies, we demonstrated the expression of complosome proteins including C3, C5, C3aR, and cathepsin L in purified HSPCs.

Very small embryonic-like stem cells (VSELs) on the way for potential applications in regenerative medicine.

Evidence has accumulated that adult tissues contain a population of early development stem cells capable of differentiating across germ layers into various types of cells. Our group purified these rare cells, naming them very small embryonic-like stem cells (VSELs). With their broad differentiation potential, VSELs have emerged as a new candidate population for clinical applications.

Complosome Regulates Hematopoiesis at the Mitochondria Level.

The intracellular complement network, known as the complosome, regulates lymphocyte biology, which is well established. Recently, however, we demonstrated that the complosome is also expressed in hematopoietic stem/progenitor cells (HSPCs) in addition to lymphocytes. In our previous work, murine lineage-negative (Lin) bone marrow (BM) mononuclear cells (BMMNC) from mice lacking the intracellular C3 and C5 complosome proteins displayed different responses to stress.

Extracellular microvesicles/exosomes-magic bullets in horizontal transfer between cells of mitochondria and molecules regulating mitochondria activity.

Extracellular microvesicles (ExMVs) were one of the first communication platforms between cells that emerged early in evolution. Evidence indicates that all types of cells secrete these small circular structures surrounded by a lipid membrane that plays an important role in cellular physiology and some pathological processes. ExMVs interact with target cells and may stimulate them by ligands expressed on their surface and/or transfer to the target cells their cargo comprising various RNA species, proteins, bioactive lipids, and signaling nucleotides.

Mitochondria Express Functional Signaling Ligand-Binding Receptors that Regulate their Biological Responses - the Novel Role of Mitochondria as Stress-Response Sentinels.

Evidence accumulated mitochondria, as the "powerplants of the cell," express several functional receptors for external ligands that modify their function and regulate cell biology. This review sheds new light on the role of these organelles in sensing external stimuli to facilitate energy production for cellular needs. This is possible because mitochondria express some receptors on their membranes that are responsible for their autonomous responses.

Next-generation sequencing protocol of hematopoietic stem cells (HSCs). Step-by-step overview and troubleshooting guide.

Populations of very small embryonic-like stem cells (VSELs) (CD34+lin-CD45- and CD133+lin-CD45-), circulating in the peripheral blood of adults in small numbers, have been identified in several human tissues and together with the populations of hematopoietic stem cells (HSCs) (CD34+lin-CD45+) and CD133+lin-CD45+constitute a pool of cells with self-renewal and pluripotent stem cell characteristics. Using advanced cell staining and sorting strategies, we isolated populations of VSELs and HSCs for bulk RNA-Seq analysis to compare the transcriptomic profiles of both cell populations. Libraries were prepared from an extremely small number of cells; however, their good quality was preserved, and they met the criteria for sequencing.

Potassium/sodium cation carriers robustly upregulate CD20 antigen by targeting MYC, and synergize with anti- CD20 immunotherapies to eliminate malignant B cells.

Our investigation uncovers that nanomolar concentrations of salinomycin, monensin, nigericin, and narasin (a group of potassium/ sodium cation carriers) robustly enhance surface expression of CD20 antigen in B-cell-derived tumor cells, including primary malignant cells of chronic lymphocytic leukemia and diffuse large B-cell lymphoma. Experiments in vitro, ex vivo, and animal model reveal a novel approach of combining salinomycin or monensin with therapeutic anti-CD20 monoclonal antibodies or anti-CD20 chimeric antigen receptor T cells, significantly improving non-Hodgkin lymphoma therapy. The results of RNA sequencing, genetic editing, and chemical inhibition delineate the molecular mechanism of CD20 upregulation, at least partially, to the downregulation of MYC, the transcriptional repressor of the MS4A1 gene encoding CD20.

The Different Responsiveness of C3- and C5-deficient Murine BM Cells to Oxidative Stress Explains Why C3 Deficiency, in Contrast to C5 Deficiency, Correlates with Better Pharmacological Mobilization and Engraftment of Hematopoietic Cells.

The liver-derived circulating in peripheral blood and intrinsic cell-expressed complement known as complosome orchestrate the trafficking of hematopoietic stem/progenitor cells (HSPCs) both during pharmacological mobilization and homing/engraftment after transplantation. Our previous research demonstrated that C3 deficient mice are easy mobilizers, and their HSPCs engraft properly in normal mice. In contrast, C5 deficiency correlates with poor mobilization and defects in HSPCs' homing and engraftment.

Defect in Migration of HSPCs in Nox-2 Deficient Mice Explained by Impaired Activation of Nlrp3 Inflammasome and Impaired Formation of Membrane Lipid Rafts.

NADPH oxidase 2 (Nox2), a superoxide-generating enzyme, is a source of reactive oxygen species (ROS) that regulate the intracellular redox state, self-renewal, and fate of hematopoietic stem/progenitor cells (HSPCs). Nox2 complex expressed on HSPCs associated with several activated cell membrane receptors increases the intracellular level of ROS. In addition, ROS are also released from mitochondria and, all together, are potent activators of intracellular pattern recognition receptor Nlrp3 inflammasome, which regulates the trafficking, proliferation, and metabolism of HSPCs.

Murine and Human-Purified very Small Embryonic-like Stem Cells (VSELs) Express Purinergic Receptors and Migrate to Extracellular ATP Gradient.

Purinergic signaling is an ancient primordial signaling system regulating tissue development and specification of various types of stem cells. Thus, functional purinergic receptors are present in several types of cells in the body, including multiple populations of stem cells. However, one stem cell type that has not been evaluated for expression of purinergic receptors is very small embryonic stem cells (VSELs) isolated from postnatal tissues.

Hematopoiesis Revolves Around the Primordial Evolutional Rhythm of Purinergic Signaling and Innate Immunity - A Journey to the Developmental Roots.

A cell's most significant existential task is to survive by ensuring proper metabolism, avoiding harmful stimuli, and adapting to changing environments. It explains why early evolutionary primordial signals and pathways remained active and regulate cell and tissue integrity. This requires energy supply and a balanced redox state.

The "Mystery Cell Population" Residing in Murine Bone Marrow - A Missing Link Between Very Small Embryonic Like Stem Cells and Hematopoietic Stem Cells?

Bone marrow (BM) contains not only hematopoietic stem cells (HSCs) but also some very rare, early development, small quiescent stem cells that, upon activation, may differentiate across germlines. These small cells, named very small embryonic like stem cells (VSELs), can undergo specification into several types of cells including HSCs. Interestingly, murine BM is also home to a "mystery" population of small CD45 stem cells with many of the phenotypic characteristics attributed to resting HSCs.

Molecular analysis and comparison of CD34 and CD133 very small embryonic-like stem cells purified from umbilical cord blood.

Very small embryonic like stem cells (VSELs) are a dormant population of stem cells that, as proposed, are deposited during embryogenesis in various tissues, including bone marrow (BM). These cells are released under steady state conditions from their tissue locations and circulate at a low level in peripheral blood (PB). Their number increases in response to stressors as well as tissue/organ damage.

External Liver-Derived Complement and Intrinsic Present in Hematopoietic Stem/Progenitor Cells Complosome Modulate Cell Metabolism and Response to Stress.

Hematopoietic stem/progenitor cells (HSPCs) express receptors for complement cascade (ComC) cleavage fragments C3a and C5a and may respond to inflammation-related cues by sensing pathogen-associated molecular pattern molecules (PAMPs) released by pathogens as well as non-infectious danger associated molecular pattern molecules (DAMPs) or alarmin generated during stress/tissue damage sterile inflammation. To facilitate this HSPCs are equipped with C3a and C5a receptors, C3aR and C5aR, respectively, and express on the outer cell membrane and in cytosol pattern recognition receptors (PPRs) that sense PAMPs and DAMPs. Overall, danger-sensing mechanisms in HSPCs mimic those seen in immune cells, which should not surprise as hematopoiesis and the immune system develop from the same common stem cell precursor.

Identification of cardiac-related serum miRNA in patients with type 2 diabetes mellitus and heart failure: Preliminary report.

Background: Diabetic patients present an increased risk for heart failure (HF) independently of the presence of coronary artery disease (CAD) and hypertension. However, little is known about circulatory microRNA (miRNA), an important regulatory RNA in this population.

Objectives: To evaluate serum miRNA profile of patients with diabetes mellitus (DM) and HF and analyze its relationship with pathophysiological pathways involved.

The Nox2-ROS-Nlrp3 Inflammasome Signaling Stimulates in the Hematopoietic Stem/Progenitor Cells Lipogenesis to Facilitate Membrane Lipid Raft Formation.

Proliferation, metabolism, and migration of hematopoietic stem/progenitor cells (HSPCs) are coordinated by receptors expressed on outer cell membranes that are integrated into microdomains, known as membrane lipid rafts (MLRs). These structures float freely in the cell membrane bilayer and are enriched in cholesterol and sphingolipids for their functional integrity. Receptors, if expressed in MLRs, have prolonged occupancy on the cell surface and enhanced signaling power.

Purinergic Signaling and Its Role in Mobilization of Bone Marrow Stem Cells.

Mobilization or egress of stem cells from bone marrow (BM) into peripheral blood (PB) is an evolutionary preserved and important mechanism in an organism for self-defense and regeneration. BM-derived stem cells circulate always at steady-state conditions in PB, and their number increases during stress situations related to (a) infections, (b) tissue organ injury, (c) stress, and (d) strenuous exercise. Stem cells also show a circadian pattern of their PB circulating level with peak in early morning hours and nadir late at night.

Novel evidence that the P2X1 purinergic receptor-Nlrp3 inflammasome axis orchestrates optimal trafficking of hematopoietic stem progenitors cells.

Introduction: Our previous research demonstrated P2X purinergic receptors as important extracellular adenosine triphosphate (eATP) sensing receptors promoting the trafficking of hematopoietic stem progenitor cells (HSPCs). Accordingly, mice deficient in expression of P2X4 and P2X7 receptors turned out to mobilize poorly HSPCs. Similarly, defective expression of these receptors on transplanted HSPCs or in the bone marrow (BM) microenvironment of graft recipient mice led to defective homing, engraftment, and delayed hematopoietic reconstitution.

Proteomic Analysis of Murine Bone Marrow Very Small Embryonic-like Stem Cells at Steady-State Conditions and after In Vivo Stimulation by Nicotinamide and Follicle-Stimulating Factor Reflects their Germ-Lineage Origin and Multi Germ Layer Differentiation Potential.

Very small embryonic-like stem cells (VSELs) are a dormant population of development early stem cells deposited in adult tissues that as demonstrated contribute to tissue/organ repair and regeneration. We postulated developmental relationship of these cells to migrating primordial germ cells (PGCs) and explained the quiescent state of these cells by the erasure of differently methylated regions (DMRs) at some of the paternally imprinted genes involved in embryogenesis. Recently, we reported that VSELs began to proliferate and expand in vivo in murine bone marrow (BM) after exposure to nicotinamide (NAM) and selected pituitary and gonadal sex hormones.