Proteomics characterisation of the L929 cell supernatant and its role in BMDM differentiation

BMDMs are a key model system to study macrophage biology in vitro. Commonly used methods to differentiate macrophages from BM are treatment with either recombinant M-CSF or the supernatant of L929 cells, which secrete M-CSF. However, little is known about the composition of L929 cell-conditioned media (LCCM) and how it affects the BMDM phenotype. Here, we used quantitative mass spectrometry to characterise the kinetics of protein secretion from L929 cells over a 2-wk period, identifying 2,193 proteins. Whereas M-CSF is very abundant in LCCM, we identified several other immune-regulatory proteins such as macrophage migration inhibitory factor (MIF), osteopontin, and chemokines such as Ccl2 and Ccl7 at surprisingly high abundance levels. We therefore further characterised the proteomes of BMDMs after differentiation with M-CSF, M-CSF + MIF, or LCCM, respectively. Interestingly, macrophages differentiated with LCCM induced a stronger anti-inflammatory M1 phenotype that those differentiated with M-CSF. This resource will be valuable to all researchers using LCCM for the differentiation of BMDMs.

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Proteomics characterisation of the L929 cell supernatant and its role in BMDM differentiation

10.1101/2020.08.20.259515 ◽

2020 ◽

Author(s):

Rachel E. Heap ◽

José Luis Marín-Rubio ◽

Julien Peltier ◽

Tiaan Heunis ◽

Abeer Dannoura ◽

...

Keyword(s):

Bone Marrow ◽

Macrophage Migration Inhibitory Factor ◽

L929 Cell ◽

Regulatory Proteins ◽

Quantitative Mass Spectrometry ◽

L929 Cells ◽

M1 Phenotype ◽

Kinetics Of ◽

Cell Supernatant

AbstractBone marrow-derived macrophages (BMDMs) are a key model system to study macrophage biology in vitro. Commonly used methods to differentiate macrophages from bone marrow are treatment with either recombinant M-CSF or the supernatant of L929 cells, which secrete M-CSF. However, little is known about the composition of L929 cell conditioned media (LCCM) and how it affects BMDM phenotype. Here, we used quantitative mass spectrometry to characterise the kinetics of protein secretion from L929 cells over a two-week period, identifying 2,193 proteins. While M-CSF is very abundant in LCCM, we identified several other immune-regulatory proteins such as macrophage migration inhibitory factor (MIF), osteopontin and chemokines such as Ccl2 and Ccl7 at surprisingly high abundance levels. We therefore further characterised the proteomes of BMDMs after differentiation with M-CSF, M-CSF + MIF or LCCM, respectively. Interestingly, macrophages differentiated with LCCM induced a stronger anti-inflammatory M1 phenotype that those differentiated with M-CSF. This resource will be valuable to all researchers using LCCM for the differentiation of BMDMs.

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Assembly of the 30S ribosomal subunit

Quarterly Reviews of Biophysics ◽

10.1017/s0033583506004264 ◽

2006 ◽

Vol 38 (4) ◽

pp. 397-403 ◽

Cited By ~ 15

Author(s):

James R. Williamson

Keyword(s):

Ribosome Biogenesis ◽

Energy Landscape ◽

Ribosomal Subunit ◽

Kinetic Studies ◽

Model System ◽

Quantitative Mass Spectrometry ◽

Rna Molecules ◽

Small Proteins ◽

Assembly Kinetics

The assembly of ribosomes requires a significant fraction of the energy expenditure for rapidly growing bacteria. The ribosome is composed of three large RNA molecules and over 50 small proteins that must be rapidly and efficiently assembled into the molecular machine responsible for protein synthesis. For over 30 years, the 30S ribosome has been a key model system for understanding the process of ribosome biogenesis through in vitro assembly experiments. We have recently developed an isotope pulse-chase experiment using quantitative mass spectrometry that permits assembly kinetics to be measured in real time. Kinetic studies have revealed an assembly energy landscape that ensures efficient assembly by a flexible and robust pathway.

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Effect of pH and inhibitors on beta-amyloid fibril assembly

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100166221 ◽

1996 ◽

Vol 54 ◽

pp. 752-753

Author(s):

Beverly E. Maleeff ◽

Timothy K. Hart ◽

Stephen J. Wood ◽

Ronald Wetzel

Keyword(s):

Amyloid Fibril ◽

Peptide Fragment ◽

Hydrophobic Peptides ◽

Amyloid Fibril Formation ◽

Effects Of Ph ◽

Severity Of The Disease ◽

Kinetics Of ◽

The Brain

Alzheimer's disease is characterized post-mortem in part by abnormal extracellular neuritic plaques found in brain tissue. There appears to be a correlation between the severity of Alzheimer's dementia in vivo and the number of plaques found in particular areas of the brain. These plaques are known to be the deposition sites of fibrils of the protein β-amyloid. It is thought that if the assembly of these plaques could be inhibited, the severity of the disease would be decreased. The peptide fragment Aβ, a precursor of the p-amyloid protein, has a 40 amino acid sequence, and has been shown to be toxic to neuronal cells in culture after an aging process of several days. This toxicity corresponds to the kinetics of in vitro amyloid fibril formation. In this study, we report the biochemical and ultrastructural effects of pH and the inhibitory agent hexadecyl-N-methylpiperidinium (HMP) bromide, one of a class of ionic micellar detergents known to be capable of solubilizing hydrophobic peptides, on the in vitro assembly of the peptide fragment Aβ.

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Kinetics of α-amylase and α-glucosidase inhibitory potential of Eucalyptus obliqua ethanolic leaf extract: An in vitro assessment

Planta Medica ◽

10.1055/s-0036-1596325 ◽

2016 ◽

Vol 81 (S 01) ◽

pp. S1-S381

Author(s):

S Sabiu ◽

AOT Ashafa

Keyword(s):

Leaf Extract ◽

In Vitro Assessment ◽

Inhibitory Potential ◽

Kinetics Of ◽

Ethanolic Leaf Extract

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Kinetics of Various 99mTc-Sn-Pyrophosphate Compounds in the Rat

Nuklearmedizin ◽

10.1055/s-0037-1620623 ◽

1977 ◽

Vol 16 (04) ◽

pp. 157-162 ◽

Cited By ~ 1

Author(s):

C. Schümichen ◽

B. Mackenbrock ◽

G. Hoffmann

Keyword(s):

Normal Saline ◽

Half Life ◽

Compound A ◽

Short Half Life ◽

Low Concentrations ◽

The Stability ◽

Kinetics Of ◽

In Vitro Stability

SummaryThe bone-seeking 99mTc-Sn-pyrophosphate compound (compound A) was diluted both in vitro and in vivo and proved to be unstable both in vitro and in vivo. However, stability was much better in vivo than in vitro and thus the in vitro stability of compound A after dilution in various mediums could be followed up by a consecutive evaluation of the in vivo distribution in the rat. After dilution in neutral normal saline compound A is metastable and after a short half-life it is transformed into the other 99mTc-Sn-pyrophosphate compound A is metastable and after a short half-life in bone but in the kidneys. After dilution in normal saline of low pH and in buffering solutions the stability of compound A is increased. In human plasma compound A is relatively stable but not in plasma water. When compound B is formed in a buffering solution, uptake in the kidneys and excretion in urine is lowered and blood concentration increased.It is assumed that the association of protons to compound A will increase its stability at low concentrations while that to compound B will lead to a strong protein bond in plasma. It is concluded that compound A will not be stable in vivo because of a lack of stability in the extravascular space, and that the protein bond in plasma will be a measure of its in vivo stability.

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Acquired Haemophilia: Functional Study of Antibodies to Factor VIII

Thrombosis and Haemostasis ◽

10.1055/s-0038-1650189 ◽

1981 ◽

Vol 45 (03) ◽

pp. 285-289 ◽

Cited By ~ 14

Author(s):

J P Allain ◽

A Gaillandre ◽

D Frommel

Keyword(s):

Factor Viii ◽

Functional Study ◽

Factor Viii Inhibitor ◽

Acquired Haemophilia ◽

Viii Inhibitor ◽

Kinetics Of ◽

Antibody Function ◽

Native Plasma

SummaryFactor VIII complex and its interaction with antibodies to factor VIII have been studied in 17 non-haemophilic patients with factor VIII inhibitor. Low VIII:C and high VIIIR.Ag levels were found in all patients. VIII:WF levels were 50% of those of VTIIRrAg, possibly related to an increase of poorly aggregated and electrophoretically fast moving VIIIR:Ag oligomers.Antibody function has been characterized by kinetics of VIII :C inactivation, saturability by normal plasma and the slope of the affinity curve. Two major patterns were observed:1) Antibodies from 6 patients behaved similarly to those from haemophiliacs by showing second order inhibition kinetics, easy saturability and steep affinity slope (> 1).2) Antibodies from other patients, usually with lower titres, inactivated VIII :C according to complex order kinetics, were not saturable, and had a less steep affinity slope (< 0.7). In native plasma, or after mixing with factor VIII concentrate, antibodies of the second group did not form immune complexes with the whole factor VIII molecular complex. However, dissociation procedures did release some antibodies from apparently low molecular weight complexes formed in vivo or in vitro. For appropriate management of non-haemophilic patients with factor VIII inhibitor, it is important to determine the functional properties of their antibodies to factor VIII.

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Platelet Microtubule Subunit Proteins

Thrombosis and Haemostasis ◽

10.1055/s-0038-1657068 ◽

1979 ◽

Vol 42 (05) ◽

pp. 1630-1633 ◽

Cited By ~ 3

Author(s):

A G Castle ◽

N Crawford

Keyword(s):

Epithelial Cells ◽

Gel Electrophoresis ◽

Blood Platelets ◽

Polyacrylamide Gel Electrophoresis ◽

Polyacrylamide Gel ◽

Lens Epithelial Cells ◽

Molecular Weights ◽

Kinetics Of ◽

Microtubular Structures

SummaryBlood platelets contain microtubule proteins (tubulin and HMWs) which can be polymerised “in vitro” to form structures which resemble the microtubules seen in the intact platelet. Platelet tubulin is composed of two non-identical subunits a and p tubulin which have molecular weights around 55,000 but can be resolved in alkaline SDS-polyacrylamide gel electrophoresis. These subunits associate as dimers with sedimentation coefficients of about 5.7 S although it is not known whether the dimer protein is a homo- or hetero-dimer. The dimer tubulin binds the anti-mitotic drug colchicine and the kinetics of this binding are similar to those reported for neurotubulins. Platelet microtubules also contain two HMW proteins which appear to be essential and integral components of the fully assembled microtubule. These proteins have molecular weights greater than 200,000 daltons. Fluorescent labelled antibodies to platelet and brain tubulins stain long filamentous microtubular structures in bovine lens epithelial cells and this pattern of staining is prevented by exposing the cells to conditions known to cause depolymerisation of cell microtubules.

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