Reutilization of Western Blots After Chemiluminescent or Autoradiographic Detection

SummaryWe report the characterization of a monoclonal antibody (MAb) PM6/13 which recognises glycoprotein IIIa (GPIIIa) on platelet membranes and in functional studies inhibits platelet aggregation induced by all agonists examined. In platelet-rich plasma, inhibition of aggregation induced by ADP or low concentrations of collagen was accompanied by inhibition of 5-hydroxytryptamine secretion. EC50 values were 10 and 9 [H9262]g/ml antibody against ADP and collagen induced responses respectively. In washed platelets treated with the cyclooxygenase inhibitor, indomethacin, PM6/13 inhibited platelet aggregation induced by thrombin (0.2 U/ml), collagen (10 [H9262]g/ml) and U46619 (3 [H9262]M) with EC50 = 4, 8 and 4 [H9262]g/ml respectively, without affecting [14C]5-hydroxytryptamine secretion or [3H]arachidonate release in appropriately labelled cells. Studies in Fura 2-labelled platelets revealed that elevation of intracellular calcium by ADP, thrombin or U46619 was unaffected by PM6/13 suggesting that the epitope recognised by the antibody did not influence Ca2+ regulation. In agreement with the results from the platelet aggregation studies, PM6/13 was found to potently inhibit binding of 125I-fibrinogen to ADP activated platelets. Binding of this ligand was also inhibited by two other MAbs tested, namely SZ-21 (also to GPIIIa) and PM6/248 (to the GPIIb-IIIa complex). However when tested against binding of 125I-fibronectin to thrombin stimulated platelets, PM6/13 was ineffective in contrast with SZ-21 and PM6/248, that were both potent inhibitors. This suggested that the epitopes recognised by PM6/13 and SZ-21 on GPIIIa were distinct. Studies employing proteolytic dissection of 125I-labelled GPIIIa by trypsin followed by immunoprecipitation with PM6/13 and analysis by SDS-PAGE, revealed the presence of four fragments at 70, 55, 30 and 28 kDa. PM6/13 did not recognize any protein bands on Western blots performed under reducing conditions. However Western blotting analysis with PM6/13 under non-reducing conditions revealed strong detection of the parent GP IIIa molecule, of trypsin treated samples revealed recognition of an 80 kDa fragment at 1 min, faint recognition of a 60 kDa fragment at 60 min and no recognition of any product at 18 h treatment. Under similar conditions, SZ-21 recognized fragments at 80, 75 and 55 kDa with the 55kDa species persisting even after 18 h trypsin treatment. These studies confirm the epitopes recognised by PM6/13 and SZ-21 to be distinct and that PM6/13 represents a useful tool to differentiate the characteristics of fibrinogen and fibronectin binding to the GPIIb-IIIa complex on activated platelets.

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Rapid, Refined, and Robust Method for Expression, Purification, and Characterization of Recombinant Human Amyloid-beta M1-42

10.26434/chemrxiv.7725002.v1 ◽

2019 ◽

Author(s):

Priya Prakash ◽

Travis Lantz ◽

Krupal P. Jethava ◽

Gaurav Chopra

Keyword(s):

Amyloid Beta ◽

Western Blots ◽

Force Microscopy ◽

E Coli ◽

Atomic Force ◽

Set Up ◽

Short Time

Amyloid plaques found in the brains of Alzheimer’s disease (AD) patients primarily consists of amyloid beta 1-42 (Ab42). Commercially, Ab42 is synthetized using peptide synthesizers. We describe a robust methodology for expression of recombinant human Ab(M1-42) in Rosetta(DE3)pLysS and BL21(DE3)pLysS competent E. coli with refined and rapid analytical purification techniques. The peptide is isolated and purified from the transformed cells using an optimized set-up for reverse-phase HPLC protocol, using commonly available C18 columns, yielding high amounts of peptide (~15-20 mg per 1 L culture) in a short time. The recombinant Ab(M1-42) forms characteristic aggregates similar to synthetic Ab42 aggregates as verified by western blots and atomic force microscopy to warrant future biological use. Our rapid, refined, and robust technique to purify human Ab(M1-42) can be used to synthesize chemical probes for several downstream in vitro and in vivo assays to facilitate AD research.

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Novel Insights into the Regulatory Role of Nuclear Factor (Erythroid-Derived 2)-Like 2 in Oxidative Stress and Inflammation of Human Fetal Membranes

International Journal of Molecular Sciences ◽

10.3390/ijms21176139 ◽

2020 ◽

Vol 21 (17) ◽

pp. 6139 ◽

Cited By ~ 1

Author(s):

Ramkumar Menon ◽

Morgan R Peltier

Keyword(s):

Oxidative Stress ◽

Heme Oxygenase ◽

Water Soluble ◽

Fetal Membrane ◽

Fetal Membranes ◽

Peroxisome Proliferator ◽

Nuclear Factor ◽

Western Blots ◽

Adverse Pregnancy ◽

Nrf2 Expression

Fetal membrane dysfunction in response to oxidative stress (OS) is associated with adverse pregnancy outcomes. Nuclear factor (erythroid-derived 2)-like 2 (Nrf2) is one of the regulators of innate OS response. This study evaluated changes in Nrf2 expression and its downstream targets heme oxygenase (HO-1) and peroxisome proliferator-activated receptor gamma (PPARγ) in fetal membranes during OS and infection in vitro. Furthermore, we tested the roles of sulforaphane (SFN; an extract from cruciferous vegetables) and trigonelline (TRN; an aromatic compound in coffee) in regulating Nrf2 and its targets. Fetal membranes (n = 6) collected at term were placed in an organ explant system were treated with water-soluble cigarette smoke extract (CSE), an OS inducer (1:10), and lipopolysaccharide (LPS; 100 ng/mL). Nrf2 expression, expression, its enhancement by sulforaphane (SFN, 10 µM/mL) and down regulation by TRN (10uM/mL) was determined by western blots. Expression of Nrf2 response elements PPARγ (western) heme oxygenase (HO-1), and IL-6 were quantified by ELISA. CSE and LPS treatment of fetal membranes increased nrf2, but reduced HO-1 and PPARγ and increased IL-6. Co-treatment of SFN, but not with TRN, with CSE and LPS increased Nrf2 substantially, as well as increased HO-1 and PPARγ and reduced IL-6 expression. Risk factor-induced Nrf2 increase is insufficient to generate an antioxidant response in fetal membranes. Sulforaphane may enhance innate antioxidant and anti-inflammatory capacity by increasing NRF-2 expression.

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Use of monoclonal and polyclonal antibodies to detect prostatic acid phosphatase by immunoblotting.

Clinical Chemistry ◽

10.1093/clinchem/32.10.1832 ◽

1986 ◽

Vol 32 (10) ◽

pp. 1832-1835 ◽

Cited By ~ 2

Author(s):

P C Patel ◽

L Aubin ◽

J Côte

Keyword(s):

Monoclonal Antibodies ◽

Acid Phosphatase ◽

Western Blot ◽

Polyclonal Antibodies ◽

Prostatic Acid Phosphatase ◽

The Other ◽

Dot Blot ◽

Western Blots ◽

Dot Blot Assay ◽

Polyclonal Antisera

Abstract We investigated two techniques of immunoblotting--the Western blot and the dot blot--for use in detecting prostatic acid phosphatase (PAP, EC 3.1.3.2). We used polyclonal antisera to human PAP, produced in rabbits by hyperimmunization with purified PAP, and PAP-specific monoclonal antibodies in the immunoenzymatic protocols. We conclude that PAP can be readily detected by Western blots with use of polyclonal antisera, but not with monoclonal antibodies. On the other hand, using a dot blot assay, we could easily detect PAP with both polyclonal and monoclonal antibodies.

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Development of a Mucus Gland Bioreactor in Loach Paramisgurnus dabryanus

International Journal of Molecular Sciences ◽

10.3390/ijms22020687 ◽

2021 ◽

Vol 22 (2) ◽

pp. 687

Author(s):

Tong Zhou ◽

Bolan Zhou ◽

Yasong Zhao ◽

Qing Li ◽

Guili Song ◽

...

Keyword(s):

Antiviral Activity ◽

Grass Carp ◽

Single Copy ◽

Type I ◽

Western Blots ◽

Paramisgurnus Dabryanus ◽

Expression Activity ◽

Transgenic Construct ◽

Mucus Gland

Most currently available bioreactors have some defects in the expression, activity, or purification of target protein and peptide molecules, whereas the mucus gland of fish can overcome these defects to become a novel bioreactor for the biopharmaceutical industry. In this study, we have evaluated the practicability of developing a mucus gland bioreactor in loach (Paramisgurnus dabryanus). A transgenic construct pT2-krt8-IFN1 was obtained by subcloning the promoter of zebrafish keratin 8 gene and the type I interferon (IFN1) cDNA of grass carp into the SB transposon. The IFN1 expressed in CIK cells exhibited an antiviral activity against the replication of GCRV873 and activated two genes downstream of JAK-STAT signaling pathway. A transgenic loach line was then generated by microinjection of the pT2-krt8-IFN1 plasmids and in vitro synthesized capped SB11 mRNA. Southern blots indicated that a single copy of IFN1 gene was stably integrated into the genome of transgenic loach. The expression of grass carp IFN1 in transgenic loaches was detected with RT-PCR and Western blots. About 0.0825 µg of grass carp IFN1 was detected in 20 µL mucus from transgenic loaches. At a viral titer of 1 × 103 PFU/mL, plaque numbers on plates containing mucus from transgenic loaches reduced by 18% in comparison with those of the control, indicating that mucus of IFN1-transgenic loaches exhibited an antiviral activity. Thus, we have successfully created a mucus gland bioreactor that has great potential for the production of various proteins and peptides.

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Serodiagnosis and Bacterial Genome of Helicobacter pylori Infection

Toxins ◽

10.3390/toxins13070467 ◽

2021 ◽

Vol 13 (7) ◽

pp. 467

Author(s):

Aina Ichihara ◽

Hinako Ojima ◽

Kazuyoshi Gotoh ◽

Osamu Matsushita ◽

Susumu Take ◽

...

Keyword(s):

Helicobacter Pylori ◽

Antibody Titer ◽

Bacterial Genome ◽

Serum Antibody ◽

Gene Mutations ◽

Bacterial Genomes ◽

Western Blots ◽

A Genome ◽

Vaca Gene ◽

H Pylori

The infection caused by Helicobacter pylori is associated with several diseases, including gastric cancer. Several methods for the diagnosis of H. pylori infection exist, including endoscopy, the urea breath test, and the fecal antigen test, which is the serum antibody titer test that is often used since it is a simple and highly sensitive test. In this context, this study aims to find the association between different antibody reactivities and the organization of bacterial genomes. Next-generation sequences were performed to determine the genome sequences of four strains of antigens with different reactivity. The search was performed on the common genes, with the homology analysis conducted using a genome ring and dot plot analysis. The two antigens of the highly reactive strains showed a high gene homology, and Western blots for CagA and VacA also showed high expression levels of proteins. In the poorly responsive antigen strains, it was found that the inversion occurred around the vacA gene in the genome. The structure of bacterial genomes might contribute to the poor reactivity exhibited by the antibodies of patients. In the future, an accurate serodiagnosis could be performed by using a strain with few gene mutations of the antigen used for the antibody titer test of H. pylori.

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Effects of Aspergillus fumigatus Conidia on Apoptosis and Proliferation in an In Vitro Model of the Lung Microenvironment

Microorganisms ◽

10.3390/microorganisms9071435 ◽

2021 ◽

Vol 9 (7) ◽

pp. 1435

Author(s):

Hisako Kushima ◽

Toshiyuki Tsunoda ◽

Taichi Matsumoto ◽

Yoshiaki Kinoshita ◽

Koichi Izumikawa ◽

...

Keyword(s):

Cell Cycle ◽

Epithelial Cells ◽

Pulmonary Fibrosis ◽

Aspergillus Fumigatus ◽

Rna Sequencing ◽

A549 Cells ◽

Western Blots ◽

Mesenchymal Transition ◽

Expression Of Genes ◽

Nih 3T3

Background/Aim: Aspergillus is often detected in respiratory samples from patients with chronic respiratory diseases, including pulmonary fibrosis, suggesting that it can easily colonize the airways. To determine the role of Aspergillus colonization in pulmonary fibrosis, we cultured human lung epithelial A549 cells or murine embryo fibroblast NIH/3T3 cells with Aspergillus conidia in 3D floating culture representing the microenvironment. Materials and Methods: Cells were cultured in two-dimensional (2D) and three-dimensional floating (3DF) culture with heat-inactivated Aspergillus fumigatus (AF) 293 conidia at an effector-to-target cell ratio of 1:10 (early-phase model) and 1:100 (colonization model), and RNA-sequencing and Western blots (WB) were performed. Results: AF293 conidia reduced A549 cell growth in 2D and 3DF cultures and induced apoptosis in A549 spheroids in 3DF culture. RNA-sequencing revealed the increased expression of genes associated with interferon-mediated antiviral responses including MX dymamin-like GTPase 1 (MX1). Interestingly, the decreased expression of genes associated with the cell cycle was observed with a high concentration of AF293 conidia. WB revealed that epithelial-mesenchymal transition was not involved. Notably, AF293 conidia increased NIH/3T3 growth only in 3DF culture without inducing an apoptotic reaction. RNA-sequencing revealed the increased expression of genes associated with interferon signalling, including MX2; however, the decreased expression of genes associated with the cell cycle was not observed. Conclusions: AF affects both apoptosis of epithelial cells and the growth of fibroblasts. A deeper understanding of the detailed mechanisms underlying Aspergillus-mediated signaling pathway in epithelial cells and fibroblasts will help us to understand the lung microenvironment.

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Shiga Toxin 2a Binds to Complement Components C3b and C5 and Upregulates Their Gene Expression in Human Cell Lines

Toxins ◽

10.3390/toxins13010008 ◽

2020 ◽

Vol 13 (1) ◽

pp. 8

Author(s):

Sára Kellnerová ◽

Sneha Chatterjee ◽

Rafael Bayarri-Olmos ◽

Louise Justesen ◽

Heribert Talasz ◽

...

Keyword(s):

Protein Synthesis ◽

Cell Lines ◽

Gene Transcription ◽

Specific Binding ◽

Enterohemorrhagic Escherichia Coli ◽

Complement Components ◽

Western Blots ◽

Complement Proteins ◽

Uremic Syndrome ◽

Complement Gene

Enterohemorrhagic Escherichia coli (EHEC) infections can cause EHEC-associated hemolytic uremic syndrome (eHUS) via its main virulent factor, Shiga toxins (Stxs). Complement has been reported to be involved in the progression of eHUS. The aim of this study was to investigate the interactions of the most effective subtype of the toxin, Stx2a, with pivotal complement proteins C3b and C5. The study further examined the effect of Stx2a stimulation on the transcription and synthesis of these complement proteins in human target cell lines. Binding of Stx2a to C3b and C5 was evaluated by ELISA. Kidney and gut cell lines (HK-2 and HCT-8) were stimulated with varied concentrations of Stx2a. Subsequent evaluation of complement gene transcription was studied by real-time PCR (qPCR), and ELISAs and Western blots were performed to examine protein synthesis of C3 and C5 in supernatants and lysates of stimulated HK-2 cells. Stx2a showed a specific binding to C3b and C5. Gene transcription of C3 and C5 was upregulated with increasing concentrations of Stx2a in both cell lines, but protein synthesis was not. This study demonstrates the binding of Stx2a to complement proteins C3b and C5, which could potentially be involved in regulating complement during eHUS infection, supporting further investigations into elucidating the role of complement in eHUS pathogenesis.

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JNK and p38 Inhibitors Prevent Transforming Growth Factor-β1-Induced Myofibroblast Transdifferentiation in Human Graves’ Orbital Fibroblasts

International Journal of Molecular Sciences ◽

10.3390/ijms22062952 ◽

2021 ◽

Vol 22 (6) ◽

pp. 2952

Author(s):

Tzu-Yu Hou ◽

Shi-Bei Wu ◽

Hui-Chuan Kau ◽

Chieh-Chih Tsai

Keyword(s):

Growth Factor ◽

Transforming Growth Factor ◽

Mapk Pathway ◽

Transforming Growth Factor Β1 ◽

Tissue Growth ◽

Mitogen Activated Protein Kinase ◽

Tissue Inhibitors Of Metalloproteinases ◽

Western Blots ◽

Orbital Fibroblasts ◽

Tgf Β1

Transforming growth factor-β1 (TGF-β1)-induced myofibroblast transdifferentiation from orbital fibroblasts is known to dominate tissue remodeling and fibrosis in Graves’ ophthalmopathy (GO). However, the signaling pathways through which TGF-β1 activates Graves’ orbital fibroblasts remain unclear. This study investigated the role of the mitogen-activated protein kinase (MAPK) pathway in TGF-β1-induced myofibroblast transdifferentiation in human Graves’ orbital fibroblasts. The MAPK pathway was assessed by measuring the phosphorylation of p38, c-Jun N-terminal kinase (JNK), and extracellular-signal-regulated kinase (ERK) by Western blots. The expression of connective tissue growth factor (CTGF), α-smooth muscle actin (α-SMA), and fibronectin representing fibrogenesis was estimated. The activities of matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) responsible for extracellular matrix (ECM) metabolism were analyzed. Specific pharmacologic kinase inhibitors were used to confirm the involvement of the MAPK pathway. After treatment with TGF-β1, the phosphorylation levels of p38 and JNK, but not ERK, were increased. CTGF, α-SMA, and fibronectin, as well as TIMP-1 and TIMP-3, were upregulated, whereas the activities of MMP-2/-9 were inhibited. The effects of TGF-β1 on the expression of these factors were eliminated by p38 and JNK inhibitors. The results suggested that TGF-β1 could induce myofibroblast transdifferentiation in human Graves’ orbital fibroblasts through the p38 and JNK pathways.

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miR-208b Reduces the Expression of Kcnj5 in a Cardiomyocyte Cell Line

Biomedicines ◽

10.3390/biomedicines9070719 ◽

2021 ◽

Vol 9 (7) ◽

pp. 719

Author(s):

Julia Hupfeld ◽

Maximilian Ernst ◽

Maria Knyrim ◽

Stephanie Binas ◽

Udo Kloeckner ◽

...

Keyword(s):

Untranslated Region ◽

Electrical Remodeling ◽

Sequencing Data ◽

Western Blots ◽

Cardiovascular Pathology ◽

Hypertrophic Response ◽

Channel Dependent ◽

Cardiac Excitation ◽

The Impact ◽

Generation Sequencing

MicroRNAs (miRs) contribute to different aspects of cardiovascular pathology, among them cardiac hypertrophy and atrial fibrillation. Cardiac miR expression was analyzed in a mouse model with structural and electrical remodeling. Next-generation sequencing revealed that miR-208b-3p was ~25-fold upregulated. Therefore, the aim of our study was to evaluate the impact of miR-208b on cardiac protein expression. First, an undirected approach comparing whole RNA sequencing data to miR-walk 2.0 miR-208b 3′-UTR targets revealed 58 potential targets of miR-208b being regulated. We were able to show that miR-208b mimics bind to the 3′ untranslated region (UTR) of voltage-gated calcium channel subunit alpha1 C and Kcnj5, two predicted targets of miR-208b. Additionally, we demonstrated that miR-208b mimics reduce GIRK1/4 channel-dependent thallium ion flux in HL-1 cells. In a second undirected approach we performed mass spectrometry to identify the potential targets of miR-208b. We identified 40 potential targets by comparison to miR-walk 2.0 3′-UTR, 5′-UTR and CDS targets. Among those targets, Rock2 and Ran were upregulated in Western blots of HL-1 cells by miR-208b mimics. In summary, miR-208b targets the mRNAs of proteins involved in the generation of cardiac excitation and propagation, as well as of proteins involved in RNA translocation (Ran) and cardiac hypertrophic response (Rock2).

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