Bone marrow-derived allogeneic mesenchymal stem cells (MSCs) from young healthy donors are immunoprivileged and their clinical application for regenerative medicine is under evaluation. However, data ...from preclinical and initial clinical trials indicate that allogeneic MSCs after transplantation provoke a host immune response and are rejected. In the current study, we evaluated the effect of an increase in passage number in cell culture on immunoprivilege of the MSCs. Since only limited numbers of MSCs can be sourced at a time from a donor, it is imperative to expand them in culture to meet the necessary numbers required for cell therapy. Presently, the most commonly used passages for transplantation include passages (P)3-7. Therefore, in this study we included clinically relevant passages, i.e., P3, P5, and P7, for evaluation.
The immunoprivilege of MSCs was assessed with the mixed leukocyte reaction assay, where rat MSCs were cocultured with peripheral blood leukocytes for 72 h. Leukocyte-mediated cytotoxicity, apoptosis (Bax/Bcl-xl ratio), leukocyte proliferation, and alterations in cellular bioenergetics in MSCs were assessed after the coculture. Furthermore, the expression of various oxidized phospholipids (oxidized phosphatidylcholine (ox-PC)) was analyzed in MSCs using a lipidomic platform. To determine if the ox-PCs were acting in tandem with downstream intracellular protein alterations, we performed proteome analysis using a liquid chromatography/mass spectrometry (LC/MS) proteomic platform.
Our data demonstrate that MSCs were immunoprivileged at all three passages since coculture with leukocytes did not affect the survival of MSCs at P3, P5, and P7. We also found that, with an increase in the passage number of MSCs, leukocytes did not cause any significant effect on cellular bioenergetics (basal respiration rate, spare respiratory capacity, maximal respiration, and coupling efficiency). Interestingly, in our omics data, we detected alterations in some of the ox-PCs and proteins in MSCs at different passages; however, these changes were not significant enough to affect their immunoprivilege.
The outcome of this study demonstrates that an increase in passage number (from P3 to P7) in the cell culture does not have any significant effect on the immunoprivilege of MSCs.
The variations in the protein profile of aortic-valvular (AVE) and endocardial endothelial (EE) cells are currently unknown. The current study's objective is to identify differentially expressed ...proteins and associated pathways in both the endothelial cells. We used endothelial cells isolated from the porcine (
) aortic valve and endocardium for the profiling of proteins. Label-free proteomics was performed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Our proteomics analysis revealed that 29 proteins were highly expressed, and 25 proteins were less expressed in the valve than the endocardial endothelium. The cell surface markers, such as CD63, ICAM1, PECAM1, PROCR, and TFRC, were highly expressed in EE. In contrast, CD44 was highly expressed in AVE. The pathway analysis showed that metabolic process-related proteins and extracellular matrix-related proteins were enriched in valves. Differential enrichment of signaling pathways was observed in the endocardium. The hemostasis function-related proteins were increased in both endothelial cells. The proteins and pathways enriched in aortic-valvular and endocardial endothelial cells revealed the distinct phenotype of these two closely related cells.
The ‘no-reflow’ phenomenon (NRP) after primary percutaneous coronary intervention (PCI) is a serious complication among acute ST-segment elevation myocardial infarction (STEMI) patients. Herein, a ...comprehensive lipidomics approach was used to quantify over 300 distinct molecular species in circulating plasma from 126 patients with STEMI before and after primary PCI. Our analysis showed that three lipid classes: phosphatidylcholine (PC), alkylphosphatidylcholine (PC(O)), and sphingomyelin (SM), were significantly elevated (p < 0.05) in no-reflow patients before primary PCI. The levels of individual fatty acids and total fatty acid levels were significantly lower (p < 0.05) in no-reflow subjects after PCI. The grouping of patients based on ECG ST-segment resolution (STR) also demonstrated the same trend, confirming the possible role of these differential lipids in the setting of no-reflow. Sphingomyelin species, SM 41:1 and SM 41:2, was invariably positively correlated with corrected TIMI frame count (CTFC) at pre-PCI and post-PCI. The plasma levels of SM 42:1 exhibited an inverse association (p < 0.05) consistently with tumor necrosis factor-alpha (TNF-α) at pre-PCI and post-PCI. In conclusion, we identified plasma lipid profiles that distinguish individuals at risk of no-reflow and provided novel insights into how dyslipidemia may contribute to NRP after primary PCI.
Industry 4.0 being the new face of manufacturing for future, metal additive manufacturing is a key element in this framework. For metal additive manufacturing, laser-based additive manufacturing ...techniques are dominating today. However, some of the inherent technical limitations associated with these techniques lead to a significant gap between the industrial requirements and the final deliverables. Additive friction stir deposition is a promising alternative that is still in its early stages of development. This review summarizes the vital findings in AFSD with particular emphasis on microstructure evolution and physical properties. The technical limitations of laser-based AM techniques are discussed to describe the role of AFSD in their domain. AFSD is discussed sequentially covering the basic physical process, features, capabilities, and limitations. AFSD, being a solid-state thermomechanical process, results in a refined equiaxed microstructure with enhanced mechanical properties and no signs of porosity and residual stresses. In addition to this, AFSD is capable of depositing large scale components at a high build rate that leads to cost and energy-efficient fabrication. The existing limitations of the process are discussed with the scope for future improvements. This critical review concludes with the suggested strategies for the widespread adoption of AFSD.
Aortic valve stenosis (AVS) is the most common valvular disease in the developed world. AVS involves the progressive fibrocalcific remodeling of the aortic valve (AV), which impairs function and can ...ultimately lead to heart failure. Due to gaps in our understanding of the underlying mechanisms of AVS, there are no pharmacological treatments or dietary interventions known to slow AVS progression. Recent studies have begun to suggest oxylipins-a class of bioactive lipids-may be dysregulated in the valves of patients with AVS.
We utilized high-performance liquid chromatography-tandem mass spectrometry to conduct a targeted oxylipin analysis on human AV tissue and plasma from a cohort of 110 patients undergoing AV surgery.
We identified 36 oxylipins in human AV tissue with all showing significant increase in patients with severe AVS. A multivariate model including patient characteristics and valvular oxylipins identified the arachidonic acid-COX (cyclooxygenase) pathway-derived prostanoids to be the most associated with AVS severity. Plasma oxylipin levels were measured in a subset of AV surgery patients and compared with a control group of healthy participants, showing distinct oxylipin profiles between control and disease.
Our comprehensive analysis of oxylipins in the human AV identified the inflammatory and osteogenic regulating prostanoids to be positively correlated with AVS severity. This elucidation of prostanoid dysregulation warrants further research into COX inhibition to mitigate AVS.
Tuberculosis, caused by Mycobacterium tuberculosis, still remains a major global health problem. The main obstacle in eradicating this disease is the ability of this pathogen to remain dormant in ...macrophages, and then reactivate later under immuno-compromised conditions. The physiology of hypoxic nonreplicating M. tuberculosis is well-studied using many in vitro dormancy models. However, the physiological changes that take place during the shift from dormancy to aerobic growth (reactivation) have rarely been subjected to a detailed investigation. In this study, we developed an in vitro reactivation system by re-aerating the virulent laboratory strain of M. tuberculosis that was made dormant employing Wayne's dormancy model, and compared the proteome profiles of dormant and reactivated bacteria using label-free one-dimensional LC/MS/MS analysis. The proteome of dormant bacteria was analyzed at nonreplicating persistent stage 1 (NRP1) and stage 2 (NRP2), whereas that of reactivated bacteria was analyzed at 6 and 24 h post re-aeration. Proteome of normoxially grown bacteria served as the reference. In total, 1871 proteins comprising 47% of the M. tuberculosis proteome were identified, and many of them were observed to be expressed differentially or uniquely during dormancy and reactivation. The number of proteins detected at different stages of dormancy (764 at NRP1, 691 at NRP2) and reactivation (768 at R6 and 983 at R24) was very low compared with that of the control (1663). The number of unique proteins identified during normoxia, NRP1, NRP2, R6, and R24 were 597, 66, 56, 73, and 94, respectively. We analyzed various biological functions during these conditions. Fluctuation in the relative quantities of proteins involved in energy metabolism during dormancy and reactivation was the most significant observation we made in this study. Proteins that are up-regulated or uniquely expressed during reactivation from dormancy offer to be attractive targets for therapeutic intervention to prevent reactivation of latent tuberculosis.
Oxidized phospholipids (OxPLs) promote inflammation as well as low density lipoprotein (LDL) uptake through its receptor (LOX‐1) in a variety of physiological and pathological states. We investigated ...whether the proinflammatory effect of OxPL, generated during stress conditions such as ex‐vivo exposure to POVPC (1‐Palmitoyl‐2‐(5‐oxovaleroyl)‐sn‐glycero‐3‐phosphorylcholine), a derivative of oxidative phosphatidylcholines (OxPCs) of OxPL family and global heart ischemia/reperfusion (I/R), is through the activation of LOX‐1 as well as toll‐like receptor‐2 (TLR‐2). In this study, isolated cardiomyocytes exposed to POVPC as well as isolated rat hearts subjected to global I/R were analyzed. OxPCs‐mediated‐oxidative stress (OS), caused LOX‐1 activation and altered lipid homeostasis. There was an upregulation of TLR2 expression in these conditions, suggesting that TLR2‐mediated inflammation is through LOX1. Furthermore, phosphorylation of sterol regulatory element binding protein 1c (SREBP 1c) was also found be increased due to an increase in OxPCs levels, which is also promoted OS and cell death. On the other hand, LOX‐1 activation also upregulated SREBP1c‐mediated TGF‐βRII expression causing fibrosis. Out of 80 fragmented and non‐fragmented OxPCs followed in a heatmap analysis, 24 in cardiomyocytes and 25 in heart were significantly higher in these stress conditions. Eight (8) of the OxPCs were shared between cardiomyocytes and hearts (FDR < 0.001). Interestingly, one specific fragmented OxPC i.e. 1‐palmitoyl‐2‐azelaoyl‐sn‐glycero‐3‐phosphocholine (PAzPC) among 8 shared OxPCs, was common in both stress conditions. However, a second major fragmented OxPC i.e. 1‐stearoyl‐2‐azelaoyl‐sn‐glycerophosphocholine (SAzPC) was also upregulated in the heart but not in the cardiomyocyte. It appears that cardiomyocyte‐specific; PAzPC and heart‐specific; SAzPC OxPCs may mediate abnormal lipid metabolic responses causing inflammation, apoptosis and fibrosis.
Support or Funding Information
Canadian Institutes of Health Research and Research Manitoba
This is from the Experimental Biology 2019 Meeting. There is no full text article associated with this published in The FASEB Journal.
FONTAN PATHOPHYSIOLOGY AND PLASMA BILE ACIDS Shah, Ashish; Surendran, Arun; Hassan-Tash, Pedram ...
Journal of the American College of Cardiology,
03/2023, Letnik:
81, Številka:
8
Journal Article
PDF
