Alteraciones hematológicas como consecuencia de COVID-19 y sus vacunas / Hematological changes as a consequence of COVID-19 and its vaccines

El virus SARS-CoV-2 continúa infectando a millones de individuos en el mundo. Aunque los síntomas más frecuentes observados en los pacientes con COVID-19 son fiebre, fatiga y tos, en los casos severos la hipercoagulabilidad y la inflamación son dos condiciones que pueden producir complicaciones y causar daño en órganos, poniendo en riesgo la vida del paciente. Con el fin de clasificar a los pacientes durante el triaje, se han explorado diferentes marcadores hematológicos, incluidos el recuento de plaquetas, linfocitos y eosinófilos, y la relación neutrófilos/ linfocitos, entre otros. Por su parte, para la evaluación de las coagulopatías, se vienen determinando marcadores como el dímero D y el fibrinógeno. En esta revisión se abordan las coagulopatías y los parámetros hematológicos en pacientes con COVID-19, al igual que las anormalidades en la coagulación como la trombocitopenia trombótica inmune inducida por las vacunas contra el SARS-CoV-2

The SARS-CoV-2 virus continues to infect millions of individuals around the world. Although the most frequent symptoms observed in patients with COVID-19 are fever, fatigue and cough, in severe cases hypercoagulability and inflammation are two conditions that can cause complications and organ failure, putting the patient's life at risk. In order to classify patients during triage, different hematological markers have been explored, including platelet, lymphocyte, and eosinophil counts, and the neutrophil/lymphocyte ratio, among others. Furthermore, for the evaluation of coagulopathies, markers such as D-dimer and fibrinogen are being evaluated. This review addresses the coagulopathies and hematological parameters in patients with COVID-19, as well as coagulation abnormalities such as immune thrombotic thrombocytopenia induced by SARS-CoV-2 vaccines

Rab25 Deficiency Perturbs Epidermal Differentiation and Skin Barrier Function in Mice

Rab25, a member of the Rab11 small GTPase family, is central to achieving cellular polarity in epithelial tissues. Rab25 is highly expressed in epithelial cells of various tissues including breast, vagina, cervix, the gastrointestinal tract, and skin. Rab25 plays key roles in tumorigenesis, mainly by regulating epithelial differentiation and proliferation. However, its role in skin physiology is relatively unknown. In this study, we demonstrated that Rab25 knock-out (KO) mice show a skin barrier dysfunction with high trans-epidermal water loss and low cutaneous hydration. To examine this observation, we investigated the histology and epidermal differentiation markers of the skin in Rab25 KO mice. Rab25 KO increased cell proliferation at the basal layer of epidermis, whereas the supra-basal layer remained unaffected. Ceramide, which is a critical lipid component for skin barrier function, was not altered by Rab25 KO in its distribution or amount, as determined by immunohistochemistry. Notably, levels of epidermal differentiation markers, including loricrin, involucrin, and keratins (5, 14, 1, and 10) increased prominently in Rab25 KO mice. In line with this, depletion of Rab25 with single hairpin RNA increased the expression of differentiation markers in a human keratinocyte cell line, HaCaT. Transcriptomic analysis of the skin revealed increased expression of genes associated with skin development, epidermal development, and keratinocyte differentiation in Rab25 KO mice. Collectively, these results suggested that Rab25 is involved in the regulation of epidermal differentiation and proliferation.

Comparison of the Cardiomyogenic Potency of Human Amniotic Fluid and Bone Marrow Mesenchymal Stem Cells

BACKGROUND AND OBJECTIVES: Most studies in cardiac regeneration have explored bone marrow mesenchymal stem cells (BM-MSC) with variable therapeutic effects. Amniotic fluid MSC (AF-MSC) having extended self-renewal and multi-potent properties may be superior to bone marrow MSC (BM-MSC). However, a comparison of their cardiomyogenic potency has not been studied yet.METHODS: The 5-azacytidine (5-aza) treated AF-MSC and BM-MSC were evaluated for the expression of GATA-4, Nkx2.5 and ISL-1 transcripts and proteins by quantitative RT-PCR and Western blotting, respectively as well as for the expression of cardiomyogenic differentiation markers cardiac troponin-T (cTNT), beta myosin heavy chain (βMHC) and alpha sarcomeric actinin (ASA) by immunocytochemistry.RESULTS: The AF-MSC as compared to BM-MSC had significantly higher expression of GATA-4 (183.06±29.85 vs. 9.80±0.05; p<0.01), Nkx2.5 (8.3±1.4 vs. 1.82±0.32; p<0.05), and ISL-1 (39.59±4.05 vs. 4.36±0.39; p<0.01) genes as well as GATA-4 (2.01±0.5 vs. 0.6±0.1; p<0.05), NKx2.5 (1.9±0.14 vs. 0.8±0.2; p<0.01) and ISL-1 (1.7±0.3 vs. 0.9±0.1; p<0.05) proteins. The AF-MSC also had significantly elevated expression of cTNT (5.0×10⁴±0.6×10⁴ vs. 3.5 ×10⁴±0.8×10⁴; p<0.01), β-MHC (15.7×10⁴±0.9×10⁴ vs. 8.2×10⁴±0.6×10⁴; p<0.01) and ASA (18.6×10⁴±4.9×10⁴ vs. 13.1×10⁴±3.0×10⁴; p<0.05) than BM-MSC.CONCLUSIONS: Our data suggest that AF-MSC have greater cardiomyogenic potency than BM-MSC, and thus may be a better source of MSC for therapeutic applications in cardiac regenerative medicine.

Spreading Shape and Area Regulate the Osteogenesis of Mesenchymal Stem Cells

BACKGROUND: Mesenchymal stem cells (MSCs) have strong self-renewal ability and multiple differentiation potential. Some studies confirmed that spreading shape and area of single MSCs influence cell differentiation, but few studies focused on the effect of the circularity of cell shape on the osteogenic differentiation of MSCs with a confined area during osteogenic process.METHODS: In the present study, MSCs were seeded on a micropatterned island with a spreading area lower than that of a freely spreading area. The patterns had circularities of 1.0 or 0.4, respectively, and areas of 314, 628, or 1256 µm² . After the cells were grown on a micropatterned surface for 1 or 3 days, cell apoptosis and F-actin were stained and analyzed. In addition, the expression of β-catenin and three osteogenic differentiation markers were immunofluorescently stained and analyzed, respectively.RESULTS: Of these MSCs, the ones with star-like shapes and large areas promoted the expression of osteogenic differentiation markers and the survival of cells. The expression of F-actin and its cytosolic distribution or orientation also correlated with the spreading shape and area. When actin polymerization was inhibited by cytochalasin D, the shape-regulated differentiation and apoptosis of MSCs with the confined spreading area were abolished.CONCLUSION: This study demonstrated that a spreading shape of low circularity and a larger spreading area are beneficial to the survival and osteogenic differentiation of individual MSCs, which may be regulated through the cytosolic expression and distribution of F-actin.

TFAP2C increases cell proliferation by downregulating GADD45B and PMAIP1 in non-small cell lung cancer cells

BACKGROUND: Non-small cell lung cancer (NSCLC) is one of the leading causes of death in the world. NSCLC diagnosed at an early stage can be highly curable with a positive prognosis, but biomarker limitations make it difficult to diagnose lung cancer at an early stage. To identify biomarkers for lung cancer development, we previously focused on the oncogenic roles of transcription factor TFAP2C in lung cancers and revealed the molecular mechanism of several oncogenes in lung tumorigenesis based on TFAP2C-related microarray analysis. RESULTS: In this study, we analyzed microarray data to identify tumor suppressor genes and nine genes downregulated by TFAP2C were screened. Among the nine genes, we focused on growth arrest and DNA-damage-inducible beta (GADD45B) and phorbol-12-myristate-13-acetate-induced protein 1 (PMAIP1) as representative TFAP2C-regulated tumor suppressor genes. It was observed that overexpressed TFAP2C resulted in inhibition of GADD45B and PMAIP1 expressions at both the mRNA and protein levels in NSCLC cells. In addition, downregulation of GADD45B and PMAIP1 by TFAP2C promoted cell proliferation and cell motility, which are closely associated with NSCLC tumorigenesis. CONCLUSION: This study indicates that GADD45B and PMAIP1 could be promising tumor suppressors for NSCLC and might be useful as prognostic markers for use in NSCLC therapy.

Glomerulonefritis colapsante con marcadores de desdiferenciación podocitaria en síndrome hemofagocítico secundario a linfoma hepatoesplénico de células T / Collapsing glomerulonephritis with podocyte markers in hemophagocytic syndrome secondary to hepatosplenic T-cell lymphoma

El síndrome hemofagocítico es una condición clínica e histológica grave, secundaria a diferentes procesos. La glomerulonefritis colapsante es una podocitopatía proliferativa, generalmente de pronóstico desfavorable para la función renal. Se presenta un caso en el que las dos condiciones aparecieron asociadas, lo cual es una forma infrecuente de presentación del linfoma hepatoesplénico de células T. Se discute, asimismo, el papel de los marcadores de desdiferenciación podocitaria en esta glomerulopatía, y se revisan la fisiopatología y el tratamiento.

The hemophagocytic syndrome is a serious clinical-histological entity secondary to different diseases. Collapsing glomerulonephritis is a proliferative podocytopathy that usually has an unfavorable renal prognosis. We present a case in which both entities were associated, which is an infrequent form of hepatosplenic T-cell lymphoma. In addition, we review the role of the markers of podocyte dedifferentiation in this glomerulopathy and its pathophysiology and treatment.

Effect of down-regulation of growth arrest and DNA damage inducible protein 45β on PC9 lung adenocarcinoma cells / 中南大学学报(医学版)

To explore the effect of down-regulation of growth arrest and DNA damage inducible protein 45β (GADD45β) on the PC9 lung adenocarcinoma cells.
 Methods: GADD45β gene siRNA sequence was designed and synthesized, which was transfected into PC9 lung adenocarcinoma cells through lentivirus transfection. Quantitative real-time PCR (qRT-PCR) and Western blot are used to examine the mRNA and protein levels of GADD45β in PC9 cells before and after the transfection. Annexin V-allophycocyanin (APC) double-staining flow cytometry was used to detect the apoptosis level after the transfection. The intracellular DNA content after transfection was detected by flow cytometry. The percentage of the cells at each period of cell cycle was calculated, and the effect of RNA interference on the cell growth were analyzed. The effects of RNA interference on the tumor-formation ability of cells were tested by counting the number of clones. MTT assay was used to test the half maximal inhibitory concentration (IC50) of PC9 cells for gefitinib. 
 Results: The 5'-AAATCCACTTCACGCTCAT-3' sequence was identified as the effective sequence for GADD45β gene RNA interference. The mRNA and protein expression levels of GADD45β were markedly decreased (both P<0.05) at 48 h after transfection of GADD45β-siRNA, which resulted in the increased apoptosis rate (P<0.05), decreased tumor clone number (P<0.05) and increased percentage of PC9 cell at the S stage and G2/M stage (P<0.05). The IC50 for gefitinib was decreased obviously (P<0.05).
 Conclusion: Down-regulation of GADD45β can reduce the colony-forming ability of PC9 cells, promote the cell apoptosis, and enhance the sensitivity of PC9 cells to gefitinib.

Blocking Two Signals of Immuno-Activated T Cells from Antigen Presenting Cells Can Prevent Chronic GVHD of Murine / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To explore the effects of blocking TCR-CD3 and B7-CD28 signals on immune function of mice with chronic GVHD by using TJU103 and CTLA4-Ig.</p><p><b>METHODS</b>On the basis of foregoing murine model of chronic GVHD, according to interference modes after infusion 6×10 spleen cells of donor mice, the recipients were divided into 5 groups: blank control, cGVHD, TJU103 interference, CTLA4-Ig interference and TJU103+CTLA4-Ig interference groups. The score of clinical manifestation and tissue histopathology were used to evaluate the effects of all the interferences on chronic GVHD.</p><p><b>RESULTS</b>TJU103 and CTLA4-Ig could not influence the formation of the mouse chimera. The analysis of Kaplan survival curve of mice with chronic GVHD showed that the CTLA4-Ig and TJU103+CTLA4-Ig reduced the incidence of chronic GVHD, the TJU103 could delay the occurrence of chronic GVHD, but all the interference factors could not change the severity of chronic GVHD.</p><p><b>CONCLUSION</b>TJU103 can delay the onset time of chronic GVHD, and the CTLA4-Ig can reduce the incidences of cGVHD, the combining use of TJU103 and CTLA4-Ig can significantly reduce the incidence of chronic GVHD, but can not change the severity of chronic GVHD.</p>

LRRC25 plays a key role in all-trans retinoic acid-induced granulocytic differentiation as a novel potential leukocyte differentiation antigen

Leukocyte differentiation antigens (LDAs) play important roles in the immune system, by serving as surface markers and participating in multiple biological activities, such as recognizing pathogens, mediating membrane signals, interacting with other cells or systems, and regulating cell differentiation and activation. Data mining is a powerful tool used to identify novel LDAs from whole genome. LRRC25 (leucine rich repeat-containing 25) was predicted to have a role in the function of myeloid cells by a large-scale "omics" data analysis. Further experimental validation showed that LRRC25 is highly expressed in primary myeloid cells, such as granulocytes and monocytes, and lowly/intermediately expressed in B cells, but not in T cells and almost all NK cells. It was down-regulated in multiple acute myeloid leukemia (AML) cell lines and bone marrow cells of AML patients and up-regulated after all-trans retinoic acid (ATRA)-mediated granulocytic differentiation in AML cell lines and acute promyelocytic leukemia (APL; AML-M3, FAB classification) cells. Localization analysis showed that LRRC25 is a type I transmembrane molecule. Although ectopic LRRC25 did not promote spontaneous differentiation of NB4 cells, knockdown of LRRC25 by siRNA or shRNA and knockout of LRRC25 by the CRISPR-Cas9 system attenuated ATRA-induced terminal granulocytic differentiation, and restoration of LRRC25 in knockout cells could rescue ATRA-induced granulocytic differentiation. Therefore, LRRC25, a potential leukocyte differentiation antigen, is a key regulator of ATRA-induced granulocytic differentiation.

Effects of 1,25-dihydroxyvitamin D₃ on the differentiation of MC3T3-E1 osteoblast-like cells

PURPOSE: The purpose of this study was to evaluate the effects of 1,25-dihydroxyvitamin D₃ on the proliferation, differentiation, and matrix mineralization of MC3T3-E1 osteoblast-like cells in vitro. METHODS: MC3T3-E1 osteoblastic cells and 1,25-dihydroxyvitamin D₃ were prepared. Cytotoxic effects and osteogenic differentiation were evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, alkaline phosphatase (ALP) activity assay, ALP staining, alizarin red S staining, and reverse transcription-polymerase chain reaction (RT-PCR) for osteogenic differentiation markers such as ALP, collagen type I (Col-I), osteocalcin (OCN), vitamin D receptor (VDR), and glyceraldehyde 3-phosphate dehydrogenase. RESULTS: The MTT assay showed that 1,25-dihydroxyvitamin D₃ did not inhibit cell growth and that the rate of cell proliferation was higher than in the positive control group at all concentrations. ALP activity was also higher than in the positive control group at low concentrations of 1,25-dihydroxyvitamin D₃ (10−10, 10−12, and 10−14 M). RT-PCR showed that the gene expression levels of ALP, Col-I, OCN, and vitamin D receptor (VDR) were higher at a low concentration of 1,25-dihydroxyvitamin D₃ (10−12 M). Alizarin red S staining after treatment with 1,25-dihydroxyvitamin D₃ (10−12 M) showed no significant differences in the overall degree of calcification. In contrast to the positive control group, formation of bone nodules was induced in the early stages of cell differentiation. CONCLUSIONS: We suggest that 1,25-dihydroxyvitamin D₃ positively affects cell differentiation and matrix mineralization. Therefore, it may function as a stimulating factor in osteoblastic bone formation and can be used as an additive in bone regeneration treatment.

MiR-214 Regulates the Human Hair Follicle Stem Cell Proliferation and Differentiation by Targeting EZH2 and Wnt/β-Catenin Signaling Way In Vitro

miR-214 plays a major role in the self-renewal of skin tissue. However, whether miR-214 regulates the proliferation and differentiation of human hair follicle stem cells (HFSCs) is unknown. Primary HFSCs were isolated from human scalp skin tissue, cultured, and identified using flow cytometry. An miR-214 mimic and inhibitor were constructed for transfection into HFSCs. The MTS and colony formation assays examined cell proliferation. Immunofluorescence detected the localization and expression levels of TCF4, β-catenin, and differentiation markers. Luciferase reporter and TOP/FOP Flash assays investigated whether miR-214 targeted EZH2 and regulated the Wnt/β-catenin signaling pathway. Western blot determined the expression levels of enhancer of zeste homolog 2 (EZH2), Wnt/β-catenin signaling-related proteins, and HFSC differentiation markers in cells subjected to miR-214 transfection. miR-214 expression was remarkably decreased during the proliferation and differentiation of HFSCs into transit-amplifying (TA) cells. Downregulation of miR-214 promotes the proliferation and differentiation of HFSCs. Overexpression of miR-214 led to decreased expression of EZH2, β-catenin, and TCF-4, whereas downregulation of miR-214 resulted in increased expression of EZH2, β-catenin, and TCF-4 as well as TA differentiation markers. Immunofluorescence assay revealed that inhibiting miR-214 triggered the entry of β-catenin and TCF-4 into the nucleus. The luciferase reporter and TOP/FOP Flash assays demonstrated that miR-214 directly targets EZH2 and affects Wnt/β-catenin signaling. The miR-214/EZH2/β-catenin axis could be considered a candidate target in tissue engineering and regenerative medicine for HFSCs.

Effects of Syzygium aromaticum, Cinnamomum zeylanicum, and Salvia triloba extracts on proliferation and differentiation of dental pulp stem cells

Abstract Hypersensitivity, local irritative and cytotoxic effects are known for the chemical components of Syzygium aromaticum and Cinnamomum zeylanicum contained in dental materials. However, there is no intimate data in dentistry using the whole extracts of these plants and introducing new ones. Salvia triloba is a well-known anti-inflammatory plant that correspondingly could be used in several dental traumas. Objectives: We aimed to show and compare the effect of S. aromaticum, C. zeylanicum, and S. triloba extracts on dental pulp stem cells (DPSCs) proliferation, differentiation, and immune responses. Material and Methods: Using xCELLigence, a real time monitoring system, we obtained a growth curve of DPSCs with different concentrations of the Extracts. A dose of 10 μg/mL was the most efficient concentration for vitality. Osteogenic differentiation and anti-inflammatory activities were determined by using an ELISA Kit to detect early and late markers of differentiation. Results: The level of osteonectin (ON, early osteogenic marker) decreased, which indicated that the osteogenic differentiation may be accelerated with addition of extracts. However, the level of osteocalcin (OCN, late osteogenic marker and sign of calcium granulation) differed among the extracts, in which S. aromaticum presented the highest value, followed by S. triloba and C. zeylanicum. Surprisingly, the determined calcium granules were reduced in S. aromaticum and S. triloba. In response to tumor necrosis factor alpha (TNF-α), S. triloba-treated DPSCs showed the most reduced level of IL-6 cytokine level. We suggest C. zeylanicum as a promising osteogenic inducer and S. triloba as a potent anti-inflammatory agent, which could be used safely in biocomposite or scaffold fabrications for dentistry. Conclusions: Because calcium granule formation and cell viability play a critical role in hard tissue formation, S. aromaticum in dentistry should be strictly controlled, and the mechanism leading to reduced calcium granule formation should be identified.

Establishment of Immortalized Primary Human Foreskin Keratinocytes and Their Application to Toxicity Assessment and Three Dimensional Skin Culture Construction

In spite of frequent usage of primary human foreskin keratinocytes (HFKs) in the study of skin biology, senescence-induced blockage of in vitro proliferation has been a big hurdle for their effective utilization. In order to overcome this passage limitation, we first isolated ten HFK lines from circumcision patients and successfully immortalized four of them via a retroviral transduction of high-risk human papillomavirus (HPV) E6 and E7 oncogenes. We confirmed expression of a keratinocyte marker protein, keratin 14 and two viral oncoproteins in these immortalized HFKs. We also observed their robust responsiveness to various exogenous stimuli, which was evidenced by increased mRNA expression of epithelial differentiation markers and pro-inflammatory genes in response to three reactive chemicals. In addition, their applicability to cytotoxicity assessment turned out to be comparable to that of HaCaT cells. Finally, we confirmed their differentiation capacity by construction of well-stratified three dimensional skin cultures. These newly established immortalized HFKs will be valuable tools not only for generation of in vitro skin disease models but also for prediction of potential toxicities of various cosmetic chemicals.

Kinetin Improves Barrier Function of the Skin by Modulating Keratinocyte Differentiation Markers

BACKGROUND: Kinetin is a plant hormone that regulates growth and differentiation. Keratinocytes, the basic building blocks of the epidermis, function in maintaining the skin barrier. OBJECTIVE: We examined whether kinetin induces skin barrier functions in vitro and in vivo. METHODS: To evaluate the efficacy of kinetin at the cellular level, expression of keratinocyte differentiation markers was assessed. Moreover, we examined the clinical efficacy of kinetin by evaluating skin moisture, transepidermal water loss (TEWL), and skin surface roughness in patients who used kinetin-containing cream. We performed quantitative real-time polymerase chain reaction to measure the expression of keratinocyte differentiation markers in HaCaT cells following treatment. A clinical trial was performed to assess skin moisture, TEWL, and evenness of skin texture in subjects who used kinetin-containing cream for 4 weeks. RESULTS: Kinetin increased involucrin, and keratin 1 mRNA in HaCaT cells. Moreover, use of a kinetin-containing cream improved skin moisture and TEWL while decreasing roughness of skin texture. CONCLUSION: Kinetin induced the expression of keratinocyte differentiation markers, suggesting that it may affect differentiation to improve skin moisture content, TEWL, and other signs of skin aging. Therefore, kinetin is a potential new component for use in cosmetics as an anti-aging agent that improves the barrier function of skin.

Potential Role of S100A8 in Cutaneous Squamous Cell Carcinoma Differentiation

BACKGROUND: S100A8 is differentially expressed in various cell types and is associated with a number of malignant disorders. S100A8 may affect tumor biology. However, its role in cutaneous squamous cell carcinoma (SCC) is not well established. OBJECTIVE: This study aims to investigate the relationship between S100A8 and cutaneous SCC development. METHODS: We performed immunohistochemical staining to detect S100A8 expression in facial skin specimens of premalignant actinic keratosis (AK), malignant SCC, and normal tissues. In addition, we utilized postconfluence and high calcium-induced differentiation in a culture system model. Furthermore, we constructed a recombinant adenovirus expressing GFP-tagged S100A8 to investigate the role of S100A8 in SCC cell differentiation. RESULTS: S100A8 was significantly overexpressed in human cutaneous SCC compared to that in normal and AK tissues. S100A8 was gradually upregulated in SCC cells in a post-confluence-induced differentiation model. Overexpression of S100A8 in SCC cells induced by adenoviral transduction led to increased expression levels of differentiation markers, such as loricrin, involucrin, and filaggrin. S100A8 overexpression also increased loricrin and involucrin luciferase activity. CONCLUSION: S100A8 regulates cutaneous SCC differentiation and induces well-differentiated SCC formation in skin.

In vitro characterization of human dental pulp stem cells isolated by three different methods

OBJECTIVES: In this study, we characterized human dental pulp cells (HDPCs) obtained by different culture methods to establish the most suitable methodology for dental tissue engineering and regenerative endodontic applications. MATERIALS AND METHODS: HDPCs were isolated by the outgrowth method (HDPCs-OG), the enzymatic digestion method (collagenase/dispase/trypsin, HDPCs-ED), or the combination of both methods (HDPCs-Combined). The expression of mesenchymal stem cell markers (CD105, CD90, and CD73) was investigated. In vitro differentiation capacities of HDPCs into adipogenic, osteogenic, and chondrogenic lineages were compared. Differentiation markers were analyzed by quantitative reverse-transcription polymerase chain reaction (RT-PCR) and western blotting. RESULTS: Our data indicated that whole HDPCs-ED, HPDCs-OG, and HDPCs-Combined could be differentiated into adipogenic, chrondrogenic, and osteogenic cell types. However, we found that the methods for isolating and culturing HDPCs influence the differentiation capacities of cells. HDPCs-OG and HDPCs-ED were preferably differentiated into adipogenic and osteogenic cells, respectively. Differentiation markers shown by RT-PCR and western blotting analysis were mostly upregulated in the treated groups compared with the control groups. CONCLUSIONS: Our findings confirmed that cell populations formed by two different culture methods and the combined culture method exhibited different properties. The results of this study could provide an insight into regenerative endodontic treatment using HDPCs.

Coupled electrophysiological recording and single cell transcriptome analyses revealed molecular mechanisms underlying neuronal maturation

The mammalian brain is heterogeneous, containing billions of neurons and trillions of synapses forming various neural circuitries, through which sense, movement, thought, and emotion arise. The cellular heterogeneity of the brain has made it difficult to study the molecular logic of neural circuitry wiring, pruning, activation, and plasticity, until recently, transcriptome analyses with single cell resolution makes decoding of gene regulatory networks underlying aforementioned circuitry properties possible. Here we report success in performing both electrophysiological and whole-genome transcriptome analyses on single human neurons in culture. Using Weighted Gene Coexpression Network Analyses (WGCNA), we identified gene clusters highly correlated with neuronal maturation judged by electrophysiological characteristics. A tight link between neuronal maturation and genes involved in ubiquitination and mitochondrial function was revealed. Moreover, we identified a list of candidate genes, which could potentially serve as biomarkers for neuronal maturation. Coupled electrophysiological recording and single cell transcriptome analysis will serve as powerful tools in the future to unveil molecular logics for neural circuitry functions.

Effect of Fibroblast Growth Factor-2 and Retinoic Acid on Lineage Commitment of Bone Marrow Mesenchymal Stem Cells

In this study, we examined the effect of a combination of fibroblast growth factor-2 (FGF-2) and retinoic acid (RA) on osteoblast and adipocyte lineage commitment and differentiation of human bone marrow mesenchymal stem cells (BMSCs). Pretreatment of human BMSCs with FGF-2 or RA for 5 days followed by osteoblast differentiation induction showed high calcium deposition compared to control. A combination of FGF-2 and RA further induced calcium deposition compared to FGF-2 or RA alone. The enhanced mineral deposition was accompanied with the increased expression of osteoblast differentiation markers, alkaline phosphatase and osteocalcin. On the other hand, FGF-2 pretreatment followed by adipocyte differentiation induction also showed increased formation of lipid droplets in human BMSCs, whereas RA pretreatment suppressed formation of lipid droplets. However, a combination of FGF-2 and RA increased formation of lipid droplets and expression of adipocyte marker genes, including adiponectin, ADIPOQ, FABP4, peroxisome proliferator-activated receptor γ (PPARγ), and C/EBPα. During pretreatment of BMSCs with FGF-2, RA or in combination, the cells expressed similar levels of MSC surface markers such as CD29, CD44, CD90, and CD105, indicating that they maintain stem cell potential. To determine how RA cooperates with FGF-2 in osteoblast and adipocyte lineage commitment, the expression of RA receptors and intracellular lipid-binding proteins was examined. A combination of FGF-2 and RA strongly induced the expression of RA receptor α, β, γ, PPAR β/δ, CRABP-II, and FABP5. Collectively, these results demonstrate that combined pretreatment of human BMSCs with FGF-2 and RA enhances the commitment into osteoblast and adipocyte lineages through modulation of the expression of RA-related genes.

Derivation and Differentiation of Bone Marrow Mesenchymal Stem Cells from Osteoarthritis Patients

Osteoarthritis (OA) of the knee is a degenerative joint disease caused by the progressive reduction of the articular cartilage surface that leads to reduced joint function. Cartilage degeneration occurs through gradual loss in extracellular matrix components including type II collagen and proteoglycan. Due to limited inherent self repair capacity of the cartilage, the use of cell-based therapies for articular cartilage regeneration is considered promising. Bone marrow mesenchymal stem cells (BM-MSCs) are multipotent cells and are highly capable of multilineage differentiation which render them valuable for regenerative medicine. In this study, BM-MSCs were isolated from OA patients and were characterized for MSC specific CD surface marker antigens using flowcytometry and their differentiation potential into adipocytes, osteocytes and chondrocytes were evaluated using histological and gene expression studies. BM-MSCs isolated from OA patients showed short spindle shaped morphology in culture and expressed positive MSC related CD markers. They also demonstrated positive staining with oil red O, alizarin red and alcian blue following differentiation into adipocytes, osteocytes and chondrocytes, respectively. In addition, chodrogenic related genes such as collagen type II alpha1, cartilage oligomeric matrix protein, fibromodulin, and SOX9 as well as osteocytic related genes such as alkaline phosphatase, core-binding factor alpha 1, osteopontin and RUNX2 runt-related transcription factor 2 were upregulated following chondrogenic and osteogenic differentiation respectively. We have successfully isolated and characterized BM-MSCs from OA patients. Although BM-MSCs has been widely studied and their potential in regenerative medicine is reported, the present study is the first report in our series of experiments on the BMSCs isolated from OA patients at King Abdulaziz University Hospital, Jeddah, Saudi Arabia.