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Improved PTX3 ELISA!

Aug 25, 2014 3:31:30 AM

Specifications of the improved Pentraxin 3 ELISA:

  • Highest sensitivity: Range of 0.041 - 10 ng/ml
  • Very good inter- and intra tests: CV < 3% for the latest batch!
  • Excellent Linearity
  • (Almost all) plasma samples can be measured when diluted 4 and 20x
  • Recovery within 20%
  • Improved variation between samples

  

Examples of Data of the PTX3 ELISA after improvements: Sample dilutions and linearity. The sample dilution is lowered due to increased specificity and sensitivity.

  Dilution      
Sample name 5x 10x 20x 40x
#7 A1(24) triglyc no result no result 133618.5 147785.9
#18 A2(25) triglyc 2540 2916.7 3524.2 501.3
#9 B1(24) CRP 18593.3 17607.6 16352 15479.8
#24 B4(25) CRP 25236.3 27862 28672.2 27873.4
#3 C1(23) auto-ab 26382.7 24253.7 22277.9 23802.5
#12 C2(24) auto-ab 8845.5 9020.4 10173 8240.4
#13 D1(24) septic no result 71245.4 76865.7 79431.9
#26 D1(25) septic no result 61980.5 71572.1 72560.4
#5 E1(23) bilirub 26731.4 26618.7 25262.4 24747.2
#29 E1(25)bilirub 17893 18586.9 18017.5 19893

 

PTX3 ELISA - After improvement  

Samples measured by two different operators: results are consistent.

PTX3 ELISA - After improvements

 

 Data of the PTX3 ELISA before improvements:

PTX-3 ELISA before improvement

 Dilutions of the samples before improvements: sample dilutions are higher (more matrix influences). With the improvements, the dilutions for plasma samples are 4-20x.

PTX-3 ELISA before improvement

Posted in Product News By Kim Peeters

Defensins and LL-37 for Your Research!

Aug 15, 2014 7:13:06 AM

Highlighted products: the Defensins and LL-37. Find out more by clicking the flyers!

 

Defensins              LL-37

 

Posted in Product News By Kim Peeters

The role of TLR4 signaling  and OxPAPC in the pathogenesis of Atherosclerosis

Toll-like receptors (TLRs) are increasingly being recognized as a link between the innate immune system, inflammation, and atherogenesis. This family of innate immune receptors is expressed by endothelial cells, in which they trigger various signaling pathways and lead to cell activation, increased expression of inflammatory cytokines and adhesion molecules, and endothelial dysfunction. While initially identified as sensors of microbial invasion, TLRs are now known to be activated also by endogenous ligands produced in inflamed tissues, potentially leading to further inflammation. Among them, TLR4, a receptor for lipopolysaccharide (LPS) from Gram negative bacterial cell walls, also exhibits affinity for fatty acids, extracellular matrix components, fibrinogen, and various heat shock proteins. Of note, TRL4 signaling leads to activation of NF-kB, a pathway associated with endothelial injury, and TRL4 expression is increased in human atherosclerotic plaques. Several studies indicate that TLR4 may play a relevant role of in the pathogenesis of autoimmune damage in Rheumatic arthritis.

The paper of Menghini_R_2014 report results of an in vitro study indicating that TLR4 signaling in endothelial cells may be triggered by both LPS and endogenous ligands, such as oxidized phospholipids (OxPAPC), leading to endothelial cell activation and a proinflammatory phenotype. Importantly, TLR4 activation by endogenous ligands is likely to occur in the presence of a proatherosclerotic milieu, where it can contribute to maintain and amplify endothelial activation and vessel wall inflammation.

Reference:

Menghini, R et al. Toll-Like Receptor 4 Mediates Endothelial Cell Activation Through NF-kB but Is Not Associated with Endothelial Dysfunction in Patients with Rheumatoid Arthritis. PLoS ONE 9(6): e99053.

OxPAPC

Figure 1. An oxidized phospholipid (oxPAPC) inhibits LPS-induced expression of adhesion molecules in endothelial cells.

OxPAPC inhibits the binding of LPS to LBP and CD14 impairing, the intracellular signaling of LPS thru TLR-4, events downstream of TLR-4 include activation of kinase p38MAPK, phosphorylation of I- B and activation of the transcription factor NF- B will be impaired in the presence of oxPAPC. oxPAPC treatment results in decreased expression of adhesion molecules, leading to decreased neutrophil attachment and activation. In this model, reactive oxygen species like O2 from activated neutrophils oxidize PAPC, which represents a negative feedback mechanism on neutrophil recruitment and activation. Nature Medicine  8, 1084 - 1085 (2002)

Products

Product Description Quantity Cat #
PAPC 5 mg HC4043
Oxidized PAPC 5 mg HC4036
Oxidized PAPC 1 mg HC4035
Posted in Scientific Publications Product News By Kim Peeters

Oxidation products of 1-palmitoyl-2-arachidonoyl- sn -glycerol-3-phosphatidylcholine (PAPC), referred to as OxPAPC, and an active component, 1-palmitoyl-2- (5,6-epoxyisoprostane E 2 )- sn -glycero-3- hosphatidylcholine (PEIPC), accumulate in atherosclerotic lesions and regulate over 1,000 genes in human aortic endothelial cells (HAEC).

OxPAPC is a prototypic biologically active oxidized phospholipid first isolated from LDL minimally modified by oxidation (MM-LDL). OxPAPC is an active principle of MM-LDL that mimics several pro- and anti-inflammatory effects induced by oxidized lipoproteins. Oxidation of PAPC generates a mixture of oxidized phospholipids containing either fragmented or full-length oxygenated sn-2 residues. Both fragmented and full-length oxygenated species can regulate immune reactions. Pro-inflammatory effects of OxPAPC include stimulation of endothelial cells to bind monocytes and induction of tissue clotting factor, IL-8, MCP-1, G-CSF and other mediators of atherothrombosis. Anti-inflammatory effects of OxPAPC are mediated by induction of protective enzymes such as heme oxygenase-1 as well as suppression of innate immune responses to bacterial lipopolysaccharide (LPS) due to inhibition of LPS recognition by LPS-binding protein (LBP) and CD14. OxPAPC is active in vivo and was shown to protect mice in several models of acute inflammation induced by bacterial products. In addition, oxidized phospholipids present in OxPAPC are recognised by scavenger receptor CD36 and auto-antibodies present in patients with anti-phospholipid syndrome. Biological activities of OxPAPC are mediated by a variety of signal transduction mechanisms, including elevation of cAMP and Ca2+ levels, activation of MAP kinases, PI-3-kinase and small GTPases Rac-1 and Cdc42. OxPAPC-induced gene expression is mediated by transcription factors such as Egr-1, NFAT, CREB, NRF2, ATF4 but does not involve NFκB-dependent transcription.

Springstead_J_2012 reveals strong evidence that both gene regulation and covalent binding of OxPAPC involve interactions with cysteine and that this interaction is primarily from PEIPC.

They have demonstrated that cysteine plays an important role in OxPAPC regulation of endothelial function. They show that PEIPC is the major cysteine binding lipid in OxPAPC. OxPNB and 15dPGJ 2 bind to the same cysteines in H-Ras, resulting in similar H-Ras activation. There is a strong overlap in protein binding and gene regulation by PEIPC, OxPAPC, and 15dPGJ 2 in HAECs, including genes involved in inflammation, stress response, and atherosclerosis. Overall, this study strongly suggests that interaction with cysteines constitutes a major mechanism of action by PEIPC and OxPAPC in endothelial cells. Studies identifying reactive cysteines suggest that there is a strong correlation between hyperreactivity and functionality of cysteines. Thus, many of the proteins covalently binding OxPAPC in cells may play an important role in OxPAPC signaling.

Reference:

Springstead, J et al. Evidence for the importance of OxPAPC interaction with cysteines in regulating endothelial cell function. J. Lipid Res. 2012. 53:1304–1315.

Products

Product Description Quantity Cat #
PAPC 5 mg HC4043
Oxidized PAPC 5 mg HC4036
Oxidized PAPC 1 mg HC4035
Posted in Scientific Publications Product News By Kim Peeters

Immune responses that are enhanced by cell injury include trauma, necrosis or infection are primarily mediated by cell-originating DAMPs. Recently, evidence for aberrant extracellular functions of gp96 have emerged, suggesting that once exiting the cells, gp96 behaves as a DAMP molecule. Extracellular gp96 binds to TLR2/4 and to CD91, which in turn facilitate an increase in the release of pro-inflammatory cytokines. Macrophages that were introduced to synovial fluid from Rheumatic Arthritis patients, containing high levels of endogenous gp96, responded with an inflammatory flare.

In this study, they present that during inflammatory conditions, pancreatic islets are a target of gp96-mediated inflammatory damage and that this aspect of cell injury may be regulated by circulating α1-antitrypsin. α1-Antitrypsin is an anti-inflammatory protein that circulates at high levels. They showed that gp96-treated inflammatory damage was reduced by the addition of α1-antitrypsin and that IL10 release was elevated in the gp96 treated macrophage cultures after addition of α1-antitrypsin. They conclude that Islets that are presented with highly inflammatory molecular and cellular environments are injured by extracellular gp96 and protected by α1-antitrypsin.

Also in an allogenic skin transplantation model, α1-antitrypsin has decreased cell-surface expression of gp96 on macrophages that were recovered from the transplantation site.

Direct interaction between gp96 and α1-antitrypsin has been demonstrated in plasma samples from diabetes type I patients as well as in the normal secretory pathway of intracellular α1-antitrypsin. The domain of α1-antitrypsin that interacts with gp96 is unknown.

Taken together, the important activity of α1-antitrypsin may place the clinically available molecule for consideration as an added therapeutic in pathologies that are intensified by tissue damage, such as ischemic heart disease, and graft-versus-host disease.

Reference: David E. Ochayon et al. Frontiers in Immunology 2013, 4:1

Product

Alpha-1-antitrypsin, Human, clone 2C1, Cat.# HM2289

The mouse monoclonal antibody clone 2C1 recognizes polymeric forms of human alpha-1-antitrypsin.

Posted in Scientific Publications Product News By Kim Peeters

Concentrations related to CVD: CRP values which are

  • <1.0 mg/L indicate a low risk
  • 1.0-2.9 mg/L indicate an intermediate risk
  • >3.0 mg/L indicate a high risk

The standards in the hsCRP ELISA kit, cat # HK369,  have been calibrated against the NIBSC 1st International Standard, 85/506. More information? Go to the productpage of the hsCRP ELISA.

Cardiovascular Disease

Cardiovascular disease (CVD) is the leading cause of deaths worldwide. High Sensitive (hs)CRP is the novel and evolving biomarker which provides a most useful predictive indicator for subsequent cardiovascular events.

An estimated 17.3 million people died from CVDs in 2008, representing 30% of all global deaths. Of these deaths, an estimated 7.3 million were due to coronary heart disease and 6.2 million were due to stroke. The number of people who die from CVDs, mainly from heart disease and stroke, will increase to reach 23.3. million by 2030.

Most cardiovascular diseases can be prevented by addressing risk factors such as tobacco use, unhealthy diet and obesity, physical inactivity, high blood pressure, diabetes and raised lipids. (source:  World Health Organization).

Cardiovascular diseases (CVDs) are a group of disorders of the heart and blood vessels and they include:

  • coronary heart disease – disease of the blood vessels supplying the heart muscle;
  • cerebrovascular disease - disease of the blood vessels supplying the brain;
  • peripheral arterial disease – disease of blood vessels supplying the arms and legs;
  • rheumatic heart disease – damage to the heart muscle and heart valves from rheumatic fever, caused by streptococcal bacteria;
  • congenital heart disease - malformations of heart structure existing at birth;
  • deep vein thrombosis and pulmonary embolism – blood clots in the leg veins, which can dislodge and move to the heart and lungs.

More information? Go to http://www.who.int/mediacentre/factsheets/fs317/en/.

CRP in short:

  • an acute-phase protein, produced exclusively in the liver
  • present in the serum of normal persons at concentrations ranging up to 5 µg/ml
  • hsCRP: for high sensitive measurement of CRP

For general inflammation the normal CRP ELISA is recommended.

 

Posted in Product News By Kim Peeters

Highlighted: L-FABP antibody for IHC

Jun 4, 2014 7:43:48 AM

Human L-FABP antibody (clone L2B10) useful for frozen and paraffin embedded sections!

  HM2049 frozen                                HM2049 frozen

 

 

 

 

 

 

 

Immunohistochemical analysis of human L-FABP in frozen human kidney tissue using mAb L2B10 (Cat.# HM2049). The antibody was diluted respectivically 500 and 1000 times.

 HM2049 paraffin HM2049 paraffin 

 

 

 

 

 

 

 

Immunohistochemical analysis of human L-FABP in paraffin embedded human kidney tissue using mAb L2B10 (Cat.# HM2049). The antibody was diluted respectivically 1000 times and the antigen retrieval was with glycine buffer for the first section and TrisHCl buffer for the second section.

 

Posted in Product News By Kim Peeters

Tumor-produced Versican V1 enhances hCAP/LL37 expression in macrophages through activation of TLR2 and Vitamin D3 signaling to promote ovarian cancer progression in vitro

A tumor microenvironment plays a critical role in tumor initiation and promotion. This tumor microenvironment exists of innate immune cells, lymphocytes and connective tissue as well as malignant cells. Innate immune cells, which includes macrophages, release cytokines and chemokines as well as influence tumorigenesis. Tumor-associated macrophages (TAMs) are an important component of inflammatory infiltrates in tumors. The human cationic antimicrobial protein-18 (hCAP18)/LL-37 is the only known cathelicidin peptide in humans. HCAP18/LL-37 is constitutively produced in numerous cell types including macrophages, neutrophils, skin epithelial cells of the skin, gastrointestinal tract and urinary tract, by the epididymis and by respiratory epithelial cells.

The LL-37 peptide serves various functions in different immune reactions, including immune modulation, inflammatory reaction, cell proliferation, angiogenesis, and anti-apoptotic activity. LL-37 has been established as a contributor to tumorigenesis and tumor progression.

The aim of this study was to investigate the regulation mechanisms of hCAP18/LL-37 in the tumor microenvironment. Dong Li and his team report that Versican V1 derived from tumor cells enhances hCAP18/LL-37 expression in macrophages through the activation of TLR2 and subsequent vitamin D-dependent mechanisms.

Moreover it enhances the chain of cellular signaling events that promotes ovarian tumor cell proliferation and invasion. Their results propose novel mechanism for hCAP18/LL-37 regulation in the tumor microenvironment. In addition they provide insights into critical factors involved in the cancer progression.

Li, D et al. PLOS One 2013, 8:e56616

Related products

Description Cat#
LL-37/CAP-18, Human, Peptide 50 µg   HC4013  
LL-37, Human, ELISA kit 1 x 96 det.  HK321-01
LL-37/CAP-18, Human, mAb 3D11 100 µg FS IF P W  HM2070   
Posted in Scientific Publications Product News By Kim Peeters

Emphysema is a long term, progressive disease that is under the category “COPD” or Chronic Obstructive Pulmonary Disease.

Not everyone who smokes gets emphysema, and likewise not everyone who abstains from smoking does not get emphysema.

There are typically two ways that one develops emphysema: smoking or alpha-1 antitrypsin deficiency.

Smoking-induced emphysema is the most common and most preventable type of emphysema. Cigarette smoke destroys the lung tissue as well as causes inflammation of the airway that makes the disease even worse. The smoke destroys the cilia over time, which carries harmful pollutants out of the lungs and out through the nose. Without cilia, pollutants become trapped in the lungs, eating away at the tissue. The immune cells sent to fight these pollutants also become compromised by the poisons in the cigarette. Over time, this leads to an increased secretion of the enzyme neutrophil elastase, which will be further explained below.

The latter type of emphysema, Alpha-1, is caused when a person does not inherit a protective protein called alpha-1 antitrypsin (AAT), which is created in the liver. There is a natural enzyme in the body called neutrophil elastase. This enzyme breaks down damaged or aging cells or bacteria in the lungs, which is useful in keeping the lungs healthy. However, this enzyme has no sense of stopping. Thus, AAT is released by the body to inhibit the neutrophil elastase from destroying the lungs. For those individuals with no AAT, the neutrophil elastase has nothing to stop it, which leads to a continual destruction of lung tissue.

Pathology: Although the origin between the two types of emphysema differs, the development and symptoms are very similar. Lung USA has a great description of how the disease develops:

“Emphysema begins with the destruction of alveoli, small sac-like structures (resembling bunches of grapes) in the lungs where oxygen from the air is exchanged for carbon dioxide in the blood. The walls of the alveoli are thin and fragile, and are easily damaged.

The damage is irreversible and results in permanent “holes” in the tissues of the lower lungs. As alveoli are destroyed, the lungs are able to transfer less and less oxygen to the bloodstream, causing shortness of breath during exercise and eventually even at rest.

The lungs also lose their elasticity, so the patient experiences great difficulty exhaling. The bronchial tubes leading to the air sacs may collapse, which traps air in the lungs. This is the condition known as emphysema.”

Symptoms: Symptoms develop slowly, and usually never have acute phases.

  • Shortness of breath
  • Wheezing
  • Chronic cough
  • Sputum (phlegm) production
  • Recurring chest colds
  • Jaundice
  • Swelling in abdomen or legs
  • Loss of appetite or weight loss (due to the increased difficulty in eating)
  • Decrease in ability to exercise
  • Year-round allergies
  • Liver problems
  • Bronchitis
  • “Barrel Chest”, where the distance from the chest to the back increases as a result of trapped air

Age of Onset: Alpha-1 tends to develop between the ages of 32-41. Smoking-induced depends on the age of onset of smoking, amount of smoking, etc.

Diagnosis: Alpha-1 can be detected through a simple blood or liver function test. Other types of emphysema can be diagnosed through a chest x-ray, or various lung function tests which measure the amount of air expelled by the patient.

Morbidity (# of people affected): About 100,000 Americans are born with Alpha-1 Emphysema, and it affects a majority of those with it. It is estimated by the World Health Organization (WHO) that 116 million people worldwide are carriers of this disease.

16-30 million Americans in total have emphysema.

Mortality (# of deaths): As the fourth leading cause of death, about 100,000 Americans die annually from this disease.

Treatment: For those with smoking-induced emphysema, the most important thing to do is STOP SMOKING. Not only does it  halt the progression of the disease, it may actually improve over time.

Some doctors prescribe steroid therapy to those with emphysema to decrease the swelling in the body.

Also, depending on the severity of the disease, many people receive oxygen treatments, whether in the hospital or the home. This provides a more concentrated dose of “good” air, which maximizes the person’s ability to oxygenate their blood.

Alpha-1 can be treated with replacement therapy. The patient is infused with derivatives of human plasma which raises the level of AAT in the blood, halting the activity of the neutrophil elastase. It cannot be used for patients who have smoking-induced emphysema. It also does not cure the disease, but rather halts the progression. It is most effective in patients who start at the initial onset of symptoms and continue treatment throughout their life.

Those affected may also opt for a lung and/or liver transplant, depending on where the AAT deficiency more greatly affects the body. However, because of the lack of oxygen, many other vital organs can be compromised, and those who receive a transplant must take a wide regime of anti-rejection medication, which can cause side effects just as bad as the disease itself.

In addition, people with emphysema should stay out of areas with harmful pollutants, and keep breathing treatments on hand. Although there are several treatments, there is no current cure for this disease.

Interesting Facts:

  • Alpha-1 type Emphysema was discovered in 1963 by Carl-Bertil Laurell in Sweden.
  • Types combined, emphysema is the fourth leading cause of death in the United States.
  • Spencer Tracy, Dean Martin, Samuel Beckett, T. S. Eliot, and Johnny Carson all suffered from emphysema.
  • 70% of all doctor visits are respiratory related
  • About 1,000 people receive lung transplants each year
  • During a normal 24-hour period, the average number of breaths taken by a human is 23,040

Related links:

http://www.nlm.nih.gov/medlineplus/emphysema.html

http://emphysema.org/

http://www.mayoclinic.org/diseases-conditions/emphysema/basics/definition/con-20014218

http://www.emphysemafoundation.org/

Posted in Scientific Publications By Kim Peeters

Novel insights in localization & expression of C5aR and C5L2

Reference: Maaike B. van Werkhoven, Department of Internal Medicine, Division of Nephrology, University Medical Center Groningen, The Netherlands. Molecular Immunology 2013, 53:237-245

Distinct renal expression patterns for C5L2 and C5aR have been detected. The findings mentioned in the article suggest a functional role for renal C5L2 rather than being a C5a decoy receptor.

HP9036

C5L2 in human renal tissue. Staining of frozen section with antibody to human C5L2 (Cat.# HP9036).

HM2094

C5aR in human renal tissue. Staining of distal tubuli or proximal tubuli (*) in frozen section with antibody to human C5aR(Cat.# HM2094).

Posted in Scientific Publications Product News By Kim Peeters

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