Use of GATA3 and TWIST1 Immunofluorescence Staining to Assess In Vitro Syncytial Fusion Index

Background The role of miR-26a-5p expression in cardiac hypertrophy remains unclear. Herein, the effect of miR-26a-5p on cardiac hypertrophy was investigated using phenylephrine (PE)-induced cardiac hypertrophy in vitro and in a rat model of hypertension-induced hypertrophy in vivo. Methods The PE-induced cardiac hypertrophy models in vitro and vivo were established. To investigate the effect of miR-26a-5p activation on autophagy, the protein expression of autophagosome marker (LC3) and p62 was detected by western blot analysis. To explore the effect of miR-26a-5p activation on cardiac hypertrophy, the relative mRNA expression of cardiac hypertrophy related mark GSK3β was detected by qRT-PCR in vitro and vivo. In addition, immunofluorescence staining was used to detect cardiac hypertrophy related mark α-actinin. The cell surface area was measured by immunofluorescence staining. The direct target relationship between miR-26a-5p and GSK3β was confirmed by dual luciferase report. Results MiR-26a-5p was highly expressed in PE-induced cardiac hypertrophy. MiR-26a-5p promoted LC3II and decreased p62 expression in PE-induced cardiac hypertrophy in the presence or absence of lysosomal inhibitor. Furthermore, miR-26a-5p significantly inhibited GSK3β expression in vitro and in vivo. Dual luciferase report results confirmed that miR-26a-5p could directly target GSK3β. GSK3β overexpression significantly reversed the expression of cardiac hypertrophy-related markers including ANP, ACTA1 and MYH7. Immunofluorescence staining results demonstrated that miR-26a-5p promoted cardiac hypertrophy related protein α-actinin expression, and increased cell surface area in vitro and in vivo. Conclusion Our study revealed that miR-26a-5p promotes myocardial cell autophagy activation and cardiac hypertrophy by regulating GSK3β, which needs further research.

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Janus Kinase Inhibition Ameliorates Ischemic Stroke Injury and Neuroinflammation Through Reducing NLRP3 Inflammasome Activation via JAK2/STAT3 Pathway Inhibition

Frontiers in Immunology ◽

10.3389/fimmu.2021.714943 ◽

2021 ◽

Vol 12 ◽

Author(s):

Hua Zhu ◽

Zhihong Jian ◽

Yi Zhong ◽

Yingze Ye ◽

Yonggang Zhang ◽

...

Keyword(s):

Ischemic Stroke ◽

Brain Tissue ◽

Proinflammatory Cytokines ◽

Nlrp3 Inflammasome ◽

Inflammatory Responses ◽

Immunofluorescence Staining ◽

Western Blots ◽

Stat3 Pathway ◽

Stat3 Signaling

BackgroundInflammatory responses play a multiphase role in the pathogenesis of cerebral ischemic stroke (IS). Ruxolitinib (Rux), a selective oral JAK 1/2 inhibitor, reduces inflammatory responses via the JAK2/STAT3 pathway. Based on its anti-inflammatory and immunosuppressive effects, we hypothesized that it may have a protective effect against stroke. The aim of this study was to investigate whether inhibition of JAK2 has a neuroprotective effect on ischemic stroke and to explore the potential molecular mechanisms.MethodsRux, MCC950 or vehicle was applied to middle cerebral artery occlusion (MCAO) mice in vivo and an oxygen-glucose deprivation/reoxygenation (OGD/R) model in vitro. After 3 days of reperfusion, neurological deficit scores, infarct volume and brain water content were assessed. Immunofluorescence staining and western blots were used to measure the expression of NLRP3 inflammasome components. The infiltrating cells were investigated by flow cytometry. Proinflammatory cytokines were assessed by RT-qPCR. The expression of the JAK2/STAT3 pathway was measured by western blots. Local STAT3 deficiency in brain tissue was established with a lentiviral vector carrying STAT3 shRNA, and chromatin immunoprecipitation (ChIP) assays were used to investigate the interplay between NLRP3 and STAT3 signaling.ResultsRux treatment improved neurological scores, decreased the infarct size and ameliorated cerebral edema 3 days after stroke. In addition, immunofluorescence staining and western blots showed that Rux application inhibited the expression of proteins related to the NLRP3 inflammasome and phosphorylated STAT3 (P-STAT3) in neurons and microglia/macrophages. Furthermore, Rux administration inhibited the expression of proinflammatory cytokines, including TNF-α, IFN-γ, HMGB1, IL-1β, IL-2, and IL-6, suggesting that Rux may alleviate IS injury by inhibiting proinflammatory reactions via JAK2/STAT3 signaling pathway regulation. Infiltrating macrophages, B, T, cells were also reduced by Rux. Local STAT3 deficiency in brain tissue decreased histone H3 and H4 acetylation on the NLRP3 promoter and NLRP3 inflammasome component expression, indicating that the NLRP3 inflammasome may be directly regulated by STAT3 signaling. Rux application suppressed lipopolysaccharide (LPS)-induced NLRP3 inflammasome secretion and JAK2/STAT3 pathway activation in the OGD/R model in vitro.ConclusionJAK2 inhibition by Rux in MCAO mice decreased STAT3 phosphorylation, thus inhibiting the expression of downstream proinflammatory cytokines and the acetylation of histones H3 and H4 on the NLRP3 promoter, resulting in the downregulation of NLRP3 inflammasome expression.

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In well-differentiated primary human bronchial epithelial cells, TGF-β1 and TGF-β2 induce expression of furin

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.00423.2020 ◽

2020 ◽

Author(s):

Michael J O'Sullivan ◽

Jennifer A Mitchel ◽

Chimwemwe Mwase ◽

Maureen McGill ◽

Phyllis Kanki ◽

...

Keyword(s):

Liquid Interface ◽

Immunofluorescence Staining ◽

Cellular Mechanisms ◽

Specific Expression ◽

Bronchial Epithelial ◽

Cellular Entry ◽

Well Differentiated ◽

Air Liquid Interface ◽

Tgf Β1

Background: The COVID-19 pandemic is an ongoing threat to public health. Since the identification of COVID-19, the disease caused by SARS-CoV-2, no drugs have been developed to specifically target SARS-CoV-2. To develop effective and safe treatment options, a better understanding of cellular mechanisms underlying SARS-CoV-2 infection is required. To fill this knowledge gap, researchers require reliable experimental systems that express the host proteins necessary for the cellular entry of SARS-CoV-2. These proteins include the viral receptor, ACE2 and the proteases TMPRSS2 and furin. A number of studies have reported cell-type specific expression of the genes encoding these molecules. However, less is known about the protein expression of these molecules. Methods: We assessed the suitability of primary human bronchial epithelial (HBE) cells maintained in air-liquid interface (ALI) as an experimental system for studying SARS-CoV-2 infection in vitro. During cellular differentiation, we measured the expression of ACE2, TMPRSS2, and furin over progressive ALI days by RT-qPCR, western blot and immunofluorescence staining. We also explored the effect of the fibrotic cytokine TGF-b on the expression of these proteins in well-differentiated HBE cells. Results/Discussion: Like ACE2, TMPRSS2 and furin proteins are localized in differentiated ciliated cells as confirmed by immunofluorescence staining. These data suggest that well-differentiated HBE cells maintained in air-liquid interface is a reliable in vitro system for investigating cellular mechanisms of SARS-CoV-2 infection. We further identified that profibrotic mediators, TGF-β1 and TGF-β2, increase the expression of furin, which is a protease required for the cellular entry of SARS-CoV-2.

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Neuroprotective Activity ofSibjeondaebo-tangon AβPeptide-Induced Damages

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2012/459894 ◽

2012 ◽

Vol 2012 ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

Hyeon Ju Yim ◽

Jung Hwa Lim ◽

Min Hee Kim ◽

Uk Namgung ◽

Sang Ryong Lee ◽

...

Keyword(s):

Pc12 Cells ◽

Cortical Neurons ◽

Caspase 3 ◽

Apoptotic Cell ◽

Immunofluorescence Staining ◽

Neuroprotective Activity ◽

Potential Therapeutic Target ◽

Protein Levels

Background.Sibjeondaebo-tang(SJDBT) has been used to treat diverse disorders including neuropsychiatric disabilities in traditional Korean medicine.Objective. The present study aims to investigate the potential effects of SJDBT on neuroprotection against Aβ peptide-induced damage usingin vitroculture andin vivorat brain systems.Materials and Methods. PC12 cell viability was analyzed by MTT assay, and neurite arborizations and caspase 3 protein signals in cultured PC12 cells andin vivocortical neurons were analyzed by immunofluorescence staining. Phospho-Erk1/2 protein was analyzed by immunofluorescence staining and western blot analysis.Results. In PC12 cells, atrophied cell body and reduced neurite extension by Aβtreatment were recovered by SJDBT treatment. Caspase 3 protein signals were increased in Aβ-treated PC12 cells, but SJDBT treatment decreased apoptotic cell death. Caspase 3 activation in cortical neurons, which was induced similarly by Aβtreatment, was reduced by SJDBT treatment. Furthermore, phospho-Erk1/2 protein levels, which had been decreased by Aβtreatment, were elevated in the cortical neurons by SJDBT treatment.Conclusion. These data show that SJDBT may play a role in protecting from damages induced by Aβin neuronal tissue and further suggest that SJDBT can be explored as the potential therapeutic target for AD treatments in human.

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BMSCs Interactions with Adventitial Fibroblasts Display Smooth Muscle Cell Lineage Potential in Differentiation and Migration That Contributes to Neointimal Formation

Stem Cells International ◽

10.1155/2016/3196071 ◽

2016 ◽

Vol 2016 ◽

pp. 1-10 ◽

Cited By ~ 4

Author(s):

Y. Wendan ◽

J. Changzhu ◽

S. Xuhong ◽

C. Hongjing ◽

S. Hong ◽

...

Keyword(s):

Smooth Muscle ◽

Cell Lineage ◽

Immunofluorescence Staining ◽

Neointimal Formation ◽

Migration Ability ◽

Reverse Transcription Pcr ◽

Adventitial Fibroblasts ◽

And Migration

In this study a model of simulated vascular injury in vitro was used to study the characterization of bone-marrow-derived mesenchymal stem cells (BMSCs) morphology and to investigate the differentiation and migration of BMSCs in the presence of adventitial fibroblasts. BMSCs from rats were indirectly cocultured with adventitial fibroblasts in a transwell chamber apparatus for 7 days, and clonogenic assays demonstrated that BMSCs could be differentiated into smooth muscle-like cells with this process, including smooth muscleα-actin (α-SMA) expression by immunofluorescence staining. Cell morphology of BMSCs was assessed by inverted microscope, while cell proliferation was assessed by MTT assay. The expressions of TGF-β1, MMP-1, and NF-κB were detected by immunofluorescence staining and Smad3 mRNA was measured by reverse transcription PCR. Migration ability of BMSCs with DAPI-labeled nuclei was measured by laser confocal microscopy. Our results demonstrate that indirect interactions with adventitial fibroblasts can induce proliferation, differentiation, and migration of BMSCs that can actively participate in neointimal formation. Our results indicate that the pathogenesis of vascular remodeling might perform via TGF-β1/Smad3 signal transduction pathways.

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MicroRNA-195 Prevents Hippocampal Microglial Polarization Towards The M1 Phenotype Induced By Chronic Brain Hypoperfusion Through Regulating CX3CL1/CX3CR1 Signalling

10.21203/rs.3.rs-25459/v1 ◽

2020 ◽

Author(s):

Meng Mao ◽

Yi Xu ◽

Xin-Yu Zhang ◽

Lin Yang ◽

Xiao-bin An ◽

...

Keyword(s):

Culture System ◽

Molecular Mechanisms ◽

Immunofluorescence Staining ◽

Neonatal Rat ◽

Injection Technique ◽

Microglial Polarization ◽

Bv2 Cells ◽

Bilateral Carotid ◽

M1 Phenotype

Abstract Background Microglial polarization was found respond dynamically to acute brain hypoxia induced by stroke and traumatic brain injury (TBI). However, studies on the process of microglial polarization during chronic cerebral ischaemia (CCI) are limited. Our goal is to investigate the influence of CCI on microglial polarization following chronic brain hypoperfusion (CBH) and exploit potential molecular mechanisms.Methods CBH model was performed by bilateral carotid artery ligation (2VO) in rats. Using stereotaxic injection technique, lenti-pre-miR-195 and anti-miR-195 oligonucleotide fragments (lenti-pre-AMO-195) were injeted into CA1 region of the hippocampus to construct animal models with high or low expression of miR-195. Immunofluorescence staining and flow cytometry were conducted to examine the status of microglial polarization. In vitro, Transwell co-culture system was taken to investigate the role of miR-195 on neuronal-microglial communication through CX3CL1-CX3CR1 signalling. Quantitative real-time PCR was used to detect the level of miR-195 and inflammatory factors. The protein levels of CX3CL1 and CX3CR1 were evaluated by both western blot and immunofluorescence staining.Results CBH induced by 2VO initiated microglial activation in the rat hippocampus from 1 week to 8 weeks, as evaluated by increased Iba-1 immunofluorescence, that the balance between microglial polarization towards the M1 and M2 phenotypes was shifted towards the M1 phenotype and that the expression of CX3CL1 and CX3CR1 was increased at 8 w following CBH. An in vitro study in a Transwell co-culture system demonstrated that transfection of either primary cultured neonatal rat neurons (NRNs) or microglial BV2 cells with AMO-195 induced M1 polarization of BV2 cells and increased CX3CL1 and CX3CR1 expression and that these effects were reversed by miR-195 mimics. Furthermore, overexpression of miR-195 induced by lenti-pre-miR-195 prevented the changes triggered by knockdown of endogenous miR-195 induced by lentiviral vector-mediated expression of lenti-pre-AMO-195 and 2VO surgery.Conclusions Our findings conclude that downregulation of miR-195 in the hippocampus is involved in CBH-induced microglial polarization towards M1 phenotype by governing communication between neurons and microglia through the regulation of CX3CL1 and CX3CR1 signalling. This indicates that miR-195 may provide a new strategy for clinical prevention and treatment of CBH.

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Human cytomegalovirus inhibits the proliferation and invasion of extravillous cytotrophoblasts via Hippo-YAP pathway

Virology Journal ◽

10.1186/s12985-021-01681-2 ◽

2021 ◽

Vol 18 (1) ◽

Author(s):

Qiaoqiao Kong ◽

Jing Li ◽

Li Zhao ◽

Peng Shi ◽

Xiaobei Liu ◽

...

Keyword(s):

Signaling Pathway ◽

Human Cytomegalovirus ◽

Hcmv Infection ◽

Adverse Outcomes ◽

Immunofluorescence Staining ◽

Control Group ◽

Infection Model ◽

Infection Dose ◽

Extravillous Cytotrophoblasts

Abstract Background Human cytomegalovirus (HCMV) infection in utero is very common during pregnancy, which can lead to adverse outcomes in both pregnancy and progeny, but its pathogenesis has not been fully clarified. The decrease of extravillous cytotrophoblasts (EVT) invasion is an essential pathophysiological process of some pregnancy complications. Hippo-YAP signaling pathway plays an important role in regulating cell proliferation and apoptosis. However, whether YAP is involved in HCMV uterine infection remains to be studied. Methods The primary EVT was cultured and infected by the HCMV strain AD169 virus in vitro. Immunofluorescence staining of HCMVpp65 antigen was conducted afterward to confirm the establishment of an infection model. The optimal virus infection dose was determined by the EVT proliferation status in vitro. Real-time PCR was performed to examine the mRNA level of major genes involved in the Hippo pathway in EVT after HCMV infection. The effect of HCMV on the expression of YAP protein in EVT was evaluated by Immunofluorescence staining and Western blot. An in vitro cell invasion assay was carried out to analyze the influence of HCMV on EVT invasion. The changes of EVT invasion was accessed by establishing YAP silencing and over-expression models using YAP1 specific siRNA and plasmid pcDH. Results The optimal HCMV infection dose was 282.5TCID50/ml. Compared to the control group, the infection of HCMV significantly reduced the mRNA expression of Mst1, Mst2, SAV, Lats1, Lats2, Mob1, YAP1, TAZ, TEAD1-4 genes and YAP protein expression in the Hippo-YAP pathway. HCMV infection also decreased the EVT invasion. In non-infected EVT, the number of transmembrane EVT cells was significantly reduced when YAP1 gene was silenced, while it was significantly increased when YAP1 gene was over-expressed. In the HCMV-infected EVT, the number of transmembrane EVT cells significantly increased when over-expressed and eventually recovered to the level of NC. Conclusions HCMV may decrease EVT invasion by inhibiting the expression of mRNA and protein of YAP in the Hippo-YAP signaling pathway. HCMV eventually reduces the invasion ability of EVT by inhibiting multiple genes in the Hippo-YAP signaling pathway, especially inhibiting YAP which serves as the downstream effector.

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The Effect of Lecithins Coupled Decorin Nanoliposomes on Treatment of Carbon Tetrachloride-Induced Liver Fibrosis

BioMed Research International ◽

10.1155/2020/8815904 ◽

2020 ◽

Vol 2020 ◽

pp. 1-10

Author(s):

Guojun Chen ◽

Yiping Zhu ◽

Xiao Liang ◽

Xianfa Wang ◽

Weihua Yu ◽

...

Keyword(s):

Cell Proliferation ◽

Carbon Tetrachloride ◽

Bile Duct ◽

Liver Fibrosis ◽

Western Blot ◽

Immunofluorescence Staining ◽

Type I ◽

Masson Trichrome Staining

This study aimed to investigate the effect of bile duct-targeting lecithins- (PC-) coupled decorin (DCN) (PC-DCN) nanoliposomes against liver fibrosis in vitro and in vivo. We prepared PC-DCN nanoliposomes by using rat astrocytes, HSC-T6, to verify the antifibrosis effect of PC-DCN in vitro. First, we established a rat model of carbon tetrachloride-induced fibrosis. PC-DCN nanoliposomes were then injected into fibrotic rats via the portal vein or bile duct. The EdU assay was performed to analyze cell proliferation. Immunofluorescence staining was used to detect α-smooth muscle actin (α-SMA) expression. Western blot was performed to examine the expression of α-SMA, collagen type I alpha 1 (COL1A1), and transforming growth factor-β (TGF-β) protein. The levels of aspartate transaminase (AST), alanine transaminase (ALT), and total bilirubin (TBIL) were examined by enzyme-linked immunosorbent assay (ELISA) analysis. Hematoxylin and eosin (H&E) staining and Masson trichrome staining were used to determine liver tissue lesions and liver fibrosis. Compared with TGF-β group, PC-DCN treatment could significantly reduce cell proliferation. Western blot analysis indicated that the expression of α-SMA, COL1A1, and TGF-β was downregulated after treatment with PC-DCN in vitro and in vivo. Immunofluorescence staining confirmed that α-SMA expression was reduced by PC-DCN. Furthermore, H&E staining and Masson trichrome staining showed that the administration of PC-DCN nanoliposomes via the bile duct could reduce the extent of liver fibrosis. PCR analysis showed that PC-DCN administration could reduce proinflammatory cytokines IL-6, TNF-α, and IL-1β expression via the bile duct. The administration of PC-DCN nanoliposomes also significantly downregulated liver function indicators ALT, AST, and TBIL. The results of our study indicated that PC-DCN could effectively reduce the extent of liver fibrosis.

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KLF5-mediated Eppk1 expression promotes cell proliferation in cervical cancer via the p38 signaling pathway

10.21203/rs.3.rs-29332/v2 ◽

2021 ◽

Author(s):

Dong Ma ◽

Zhe Pan ◽

Quan Chang ◽

Jin-jin Zhang ◽

Xiao Liu ◽

...

Keyword(s):

Cervical Cancer ◽

Cell Proliferation ◽

Signaling Pathway ◽

Cell Lines ◽

Immunofluorescence Staining ◽

Loss Of Function ◽

Gene Test ◽

Direct Binding ◽

Epidermal Growth

Abstract Background: Epiplakin1 (Eppk1) is part of epidermal growth factor (EGF) signal and takes part in reorganization of cytoskeleton and cell proliferation. However, the role of Eppk1 in cervical cancer (CC) remains unknown.Methods: To express Eppk1 and KLF5 and their correlation, we used RNA-sequence, RT-qPCR, TCGA database and immunofluorescence staining in vitro and in different pathological cervical tissues. In CC cell lines, we tested adenovirus-mediated over expression or knockdown of KLF5 and siRNA-mediated knockdown of Eppk1 and a suiting assessment of cell proliferation and cell signaling by western blot and CCK8 tests. We studied the mechanism by which KLF5 regulates Eppk1 expression by reporter gene test and chromatin immunoprecipitation test.Results: Eppk1 expression promoted in CC tissues and cell lines compared with increased KLF5 expression. The results of immunofluorescence staining further showed the increased co-expression of Eppk1 and KLF5 correlated substantially with tumorigenesis in cervical tissues. Overexpression of KLF5 significantly increased Eppk1 expression at transcription and translation levels. Conversely, the knockdown of KLF5 by siRNA against KLF5 decreased Eppk1 expression. Mechanically, KLF5 activated Eppk1 transcription by direct binding to the Eppk1 promoter. Gain- and loss-of-function experiments reported that KLF5 promoted cell proliferation in Hela partly dependent on Eppk1 upregulation. Besides, KLF5-mediated activation of p38 signaling significantly decreased after Eppk1 knockdown compared with decline of proliferation, suggesting that Eppk1 lies upstream of p38 signaling affecting cell proliferation. Finally, Eppk1 expression is positively correlated with tumor size in clinicopathological features of CC. Conclusions: Eppk1 may be an effective therapeutic target for affecting p38 signaling pathway and cell proliferation in cervical cancer.

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Biologization of Pcl-Mesh Using Platelet Rich Fibrin (Prf) Enhances Its Regenerative Potential In Vitro

International Journal of Molecular Sciences ◽

10.3390/ijms22042159 ◽

2021 ◽

Vol 22 (4) ◽

pp. 2159

Author(s):

Sarah Al-Maawi ◽

Eva Dohle ◽

Jing Lim ◽

Paul Weigl ◽

Swee Hin Teoh ◽

...

Keyword(s):

Bone Regeneration ◽

Autologous Blood ◽

Cell Types ◽

Positive Influence ◽

Immunofluorescence Staining ◽

In Vivo Studies ◽

Osteogenic Potential ◽

Platelet Rich Fibrin

Introduction: Resorbable synthetic scaffolds are promising for different indications, especially in the context of bone regeneration. However, they require additional biological components to enhance their osteogenic potential. In addition to different cell types, autologous blood-derived matrices offer many advantages to enhance the regenerative capacity of biomaterials. The present study aimed to analyze whether biologization of a PCL-mesh coated using differently centrifuged Platelet rich fibrin (PRF) matrices will have a positive influence on primary human osteoblasts activity in vitro. A polymeric resorbable scaffold (Osteomesh, OsteoporeTM (OP), Singapore) was combined with differently centrifuged PRF matrices to evaluate the additional influence of this biologization concept on bone regeneration in vitro. Peripheral blood of three healthy donors was used to gain PRF matrices centrifuged either at High (710× g, 8 min) or Low (44× g, 8 min) relative centrifugal force (RCF) according to the low speed centrifugation concept (LSCC). OP-PRF constructs were cultured with pOBs. POBs cultured on the uncoated OP served as a control. After three and seven days of cultivation, cell culture supernatants were collected to analyze the pOBs activity by determining the concentrations of VEGF, TGF-β1, PDGF, OPG, IL-8, and ALP- activity. Immunofluorescence staining was used to evaluate the Osteopontin expression of pOBs. After three days, the group of OP+PRFLow+pOBs showed significantly higher expression of IL-8, TGF-ß1, PDGF, and VEGF compared to the group of OP+PRFHigh+pOBs and OP+pOBs. Similar results were observed on day 7. Moreover, OP+PRFLow+pOBs exhibited significantly higher activity of ALP compared to OP+PRFHigh+pOBs and OP+pOBs. Immunofluorescence staining showed a higher number of pOBs adherent to OP+PRFLow+pOBs compared to the groups OP+PRFHigh+pOBs and OP+pOBs. To the best of our knowledge, this study is the first to investigate the osteoblasts activity when cultured on a PRF-coated PCL-mesh in vitro. The presented results suggest that PRFLow centrifuged according to LSCC exhibits autologous blood cells and growth factors, seem to have a significant effect on osteogenesis. Thereby, the combination of OP with PRFLow showed promising results to support bone regeneration. Further in vivo studies are required to verify the results and carry out potential results for clinical translation.

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