Project description:Adipose-derived MSCs (AMSC) are currently utilized in clinical trials for various diseases including osteoarthritis, amyotrophic lateral sclerosis, and multiple system atrophy. Whilst AMSCs may be defined by the surface expression of classical markers including CD44, CD90, CD105, and absence of CD45, these cells may exhbit donor-to-donor differences in differentiation potential. In this study we evaluated the expression of CD36 amongst AMSCs and utilized magnetic cell sorting to enrich for CD36+ cells. Whole transcriptome RNA-sequencing was performed on unsorted, CD36+ enriched, and CD36+ depleted cells to determine gene expression difference between these populations of cells. CD36 sorted or unsorted cells were then plated and maintained in growth medium. Cells were expanded for 2 passages and passage 8 cells were plated for RNA-sequencing analysis. Trizol reagent was used to harvest cells when they were proliferating cells (~80%) or 100% confluent cells.
Project description:BACKGROUND & AIMS: The scavenger receptor CD36 has versatile immuno-metabolic actions. CD36 is abundantly expressed in the small intestinal epithelium but its impact on gut homeostasis is unknown. METHODS: Wild type (WT) and CD36-null (CD36KO) mice were fed a chow diet and small intestinal morphology assessed by immunohistochemistry and electron microscopy (EM). Inflammation was evaluated from neutrophil infiltration, expression of cytokines and toll-like receptors. Barrier integrity was determined using FITC-dextran and circulating lipopolysaccharide (LPS). Enterocyte (Ent-CD36KO) and endothelial (EC-CD36KO) CD36 null mice were generated to test contribution of epithelial versus endothelial CD36 to the intestinal phenotype. RESULTS: The small intestine of CD36KO mice fed a chow diet showed abnormal remodeling of the extracellular matrix (ECM) with altered expression of ECM and junction proteins. Hypertrophy of cell junctions and basement membranes was observed by EM. The CD36KO intestines displayed neutrophil infiltration, inflammation and compromised barrier function. Systemic leukocytosis and neutrophilia were present in CD36KO mice and there was 80% reduction of anti-inflammatory Ly6Clow monocytes important for ECM regulation and tissue repair. Bone marrow transplants supported primary contribution of tissue injury in initiation of inflammation. Studies with Ent-CD36KO mice did not support a major contribution of enterocyte CD36 while endothelial CD36 deficiency associated with neutrophil infiltration, aberrant expression of tight junctions and inflammation in the small intestine. CONCLUSION: CD36 is important for maintenance of barrier function in the small intestine. CD36 deletion causes ECM remodeling with collagen accumulation, depletion of the Ly6Clow monocyte subset and chronic inflammation. Endothelial but not enterocyte CD36 loss is a significant contributor to the spontaneous inflammation.
Project description:Tyrosine kinase inhibitors (TKIs) are highly effective for treatment of chronic myeloid leukemia (CML), but very few patients are cured. Major drawbacks with TKIs are their low efficacy in eradicating the leukemic stem cells responsible for disease maintenance and relapse upon TKI cessation. Here, we performed RNA-sequencing of flow-sorted primitive (CD34+CD38low) and progenitor (CD34+CD38+) chronic phase CML cells and identified transcriptional upregulation of 32 cell surface molecules relative to corresponding normal bone marrow cells. Focusing on novel markers with increased expression on primitive CML cells, we confirmed upregulation of the scavenger receptor CD36 and the leptin receptor (LEPR) by flow cytometry. We also delineate a subpopulation of primitive CML cells expressing CD36 that is less sensitive to imatinib treatment. Using CD36 targeting antibodies, we show that the CD36 positive cells can be targeted and killed by antibody dependent cellular cytotoxicity (ADCC). In summary, CD36 defines a subpopulation of primitive CML cells with decreased imatinib sensitivity that can be effectively targeted by ADCC using an anti-CD36 antibody.
Project description:Movement of circulating fatty acids (FAs) to parenchymal cells requires their transfer across the endothelial cell (EC) barrier. The multi-ligand receptor cluster of differentiation 36 (CD36) facilitates tissue FA uptake and is expressed in ECs and parenchymal cells such as myocytes and adipocytes. Whether tissue uptake of FAs is dependent on EC or parenchymal cell CD36, or both, is unknown. Using a cell-specific deletion approach, we show that CD36-mediated FA transport across ECs rate-limits tissue FA uptake, and its loss leads to metabolic effects in parenchymal cells.
Project description:Analysis of gene expression in BAT lacking CD36. The hypothesis tested in the present study was that genes involved in lipid metabolism and mitochondrial function would be misregulated. Results provide important information about the role of CD36 in BAT. Total RNA was obtained from the BAT of control and Cd36-/- mice subjected to an overnight fast.
Project description:Hypertrophic skin scarring following dermal injury causes extreme pain and psychological trauma for patients. Unfortuately, we do not have effective treatments to prevent or reverse skin scarring. Using RNA and ATAC sequencing of mouse and human fibroblasts, we show that JUN expressing fibroblasts are responsible for skin scarring by regulating CD36 expression. In summary, we show that CD36 antagonism by represent a therapeutic target to overcome JUN hypertrophic skin scarring.
Project description:Obesity-related muscular dysfunction and relative muscle atrophy affect an increasing number of people. Elucidating the molecular mechanisms of skeletal muscle cell development and growth may contribute to the maintenance of skeletal muscle mass in obesity. Fatty acid translocase (FAT/CD36), as a long-chain fatty acid transport protein, is crucial for lipid metabolism and signaling. CD36 is known to function in myogenic differentiation, and whether it affects the proliferation of skeletal muscle cells and the underlying mechanisms remain unclear. In this study, the effect of CD36 deficiency on skeletal muscle cell viability and proliferation was examined using C2C12 myoblasts. Results showed that the deletion of CD36 enhanced the inhibitory effect of PA on the proliferation and the promotion of apoptosis in skeletal muscle cells. Intriguingly, the silencing of CD36 suppressed cell proliferation by preventing the cell cycle from the G0/G1 phase to the S phase in a cyclin D1/CDK4-dependent manner. Overall, we demonstrated that CD36 was involved in skeletal muscle cell proliferation by cell cycle control, and these findings might facilitate the treatment of obesity-related muscle wasting.
Project description:The goal of our present work was to understand the influence parvovirus B19 infection may have on the thyroid hormone signaling pathway, as well as the nuclear receptors (NR) pathway overall. We demonstrated that B19 infection of CD36+ erythroid progenitor cells leads to downregulation of the thyroid hormone receptor α isoform. In addition to that we have shown that B19 infection modulates the expression of other members of the NR superfamily such as estrogen and retinoid receptors. CD36+ cells (StemCell Technologies) were mock-infected or infected with B19, 48 hours post infection cells were collected, total RNA was isolated, and cDNA was obtained as described above. TaqMan® array human nuclear receptors fast 96-well plates obtained from Applied Biosystems (Carlsbad, CA) were utilized in order to assess the differences of 92 nuclear receptors’ expression in mock- and B19-infected CD36+ cells. Relative quantity (RQ) values were calculated using the 2-ΔΔCt method.
Project description:Amyloid-beta (Aβ) is a key factor in the onset and progression of Alzheimer's disease (AD). Selenium (Se) compounds show promise in AD treatment. Here, we reveal that selenoprotein K (SELENOK), a selenoprotein involved in immune regulation and potentially related to AD pathology, plays a critical role in microglial immune response, migration, and phagocytosis. In vivo and in vitro studies corroborate that SELENOK deficiency inhibits microglial Aβ phagocytosis, exacerbating cognitive deficits in 5xFAD mice, which are reversed by SELENOK overexpression. Mechanistically, SELENOK is involved in CD36 palmitoylation through DHHC6, regulating CD36 localization to microglial plasma membranes and thus impacting Aβ phagocytosis. CD36 palmitoylation is reduced in the brains of AD patients and mice. Se supplementation promotes SELENOK expression and CD36 palmitoylation, enhancing microglial Aβ phagocytosis and mitigating AD progression. We have identified the regulatory mechanisms from Se-dependent selenoproteins to Aβ pathology, providing novel insights into potential therapeutic strategies involving Se and selenoproteins.