Monday, May 27, 2013

Quantibody® Cytokine Arrays

Cytokines, Adipokines, Growth Factors and Neurotrophins

We are pleased to announce addition of Antibody Arrays to our catalog. These are excellent tools for study apoptosis, inflammation, angiogenesis and  immune response and related autoimmune, inflammatory and degenerative diseases plus many forms of cancers. Check out this video.

Specific Research Applications Include:
•High-throughput profiling of cytokine expression
•Validation of semi-quantitative antibody array results
•Identifying potential molecular targets for drug development
•Identifying the molecular mechanisms of drug action
•Identifying crucial factors involved in disease processes
•Discovering biomarkers for disease management
•Discovering expression patterns for molecular classification of diseases

How Quantibody Arrays Work

We will be aggresively adding new arrays to our product offerings in June. Stay tuned for more.

Saturday, May 25, 2013

Schwann Cell-Sensory Neurons-PNS Markers

These markers a important tools for the study of Neuro-muscular diseases like Amyotrophic Lateral Sclerosis (ALS) and Multiple Sclerosis (MS).

For Neuromuscular Disease Researchers, we have some of the best Schwann Cell and Sensory/Peripheral Neuron Markers in the business.
Images: Rat mixed neuron/glial cultures stained with Peripherin (green channel) and Neurofilament alpha-internexin/NF66 (green channel). These cultures contain mostly neurons which are rich in alpha-internexin, and a subgroup which have a large amount of peripherin also, such as the prominent cell in the middle of the micrograph. Since this cell expresses large amounts of peripherin and alpha-internexin, the green and red signals superimpose to produce a golden cell. Blue is a DNA stain. Protocol on data-sheet.

Here're recent publications referencing use of these markers:
Leah R. Reznikov, Qian Dong, Jeng-Haur Chena, Thomas O. Moninger, Jung Min Park, Yuzhou Zhang, Jianyang Du, Michael S. Hildebrand, Richard J. H. Smith, Christoph O. Randak, David A. Stoltz, and Michael J. Welsh. CFTR-deficient pigs display peripheral nervous system defects at birth. anti-p75 (1:500; Neuromics)...

Gayle M. Passmore, Joanne M. Reilly, Matthew Thakur, Vanessa N. Keasberry, Stephen J. Marsh, Anthony H. Dickenson and David A. Brown. Functional significance of M-type potassium channels in nociceptive cutaneous sensory endings. Fronteirs in Molecular Science. doi: 10.3389/fnmol.2012.00063. ...neurofilament H (1:1000,Neuromics,USA)...

Leigh A Nattkemper, Zhong-Qiu Zhao, Anna J Nichols, Alexandru D P Papoiu, Carol A Shively, Zhou-Feng Chen and Gil Yosipovitch. Over-Expression of the Gastrin-Releasing Peptide in Cutaneous Nerve Fibers and its Receptor in Spinal Cord in Primates with Chronic Itch. Journal of Investigative Dermatology accepted article preview 4 April 2013; doi: 10.1038/jid.2013.166...Protein Gene Product 9.5 (PGP9.5; Neuromics, Edina, MN).

Wiebke Kallenborn-Gerhardt, Katrin Schröder, Domenico Del Turco, Ruirui Lu, Katharina Kynast, Judith Kosowski, Ellen Niederberger, Ajay M. Shah, Ralf P. Brandes, Gerd Geisslinger, and Achim Schmidtko. NADPH Oxidase-4 Maintains Neuropathic Pain after Peripheral Nerve Injury. The Journal of Neuroscience, 25 July 2012, 32(30): 10136-10145; doi: 10.1523/​JNEUROSCI.6227-11.2012...chicken anti-P-Zero or MPZ (1:500; Neuromics)...

Images: Micrographs depicting SSeCKS colocalization with myelination markers (CNPase and Pzero). (A) SSeCKS (red) and CNPase (green) in the lumbar spinal cord dorsal horn. The labeling appears discrete with minimal colocalization. (B) SSeCKS (red) and Pzero (green) in the L4 dorsal root ganglia. A lack of co-localization is observed and Pzero can be seen localized to putative axonal elements (arrow). (C) SSeCKS (red) and Pzero (green) in the sciatic nerve. As in the dorsal root ganglia, a lack of co-localization is observed. Both SSeCKS and Pzero can be seen localized to axonal elements. (D) SSeCKS (red) and Pzero (green) in glabrous skin of the hind-paw, fibers displaying colocalization (yellow) can be observed (arrow). Irmen et al. Journal of Brachial Plexus and Peripheral Nerve Injury 2008 3:8 doi:10.1186/1749-7221-3-8.

I will post new data and pubs as they become available.

Saturday, May 18, 2013

The Role of Obesity in Obstructive Sleep Apnea (OSA)

Intermittent Hypoxia and Leptins

Scott Mesenger recently published a Master's Thesis that implicates compelling links between Leptin Signaling and OSA: This work was done in the John Cirello Lab at University of Western Ontario. The study extensively uses our Ob-Rb Antibody to generate data.

There is a strong link between obesity and OSA. "Perhaps the single most important factor affecting OSA risk is body weight. Weight gain of 10% increases the risk of developing OSA by six-fold (Peppard et al., 2000a) and a 10% loss of body weight is estimated to decrease the apnea/hypopnea index (events/hour) by 26%  Within the obese population (BMI ≥ 30) (Wolk et al., 2003), approximately 40% experience significant OSA and approximately 70% of OSA patients are obese (Vgontzas et al., 1994), daunting numbers considering the obesity epidemic occurring in North America and estimates suggesting 41% of Americans will be obese by 2015 (Nejat et al., 2009)."

"Leptin can exert cardiovascular effects by acting centrally, as has been shown by studies introducing leptin directly into the CNS. Central administration serves to increase plasma catecholamines epinephrine and norepinephrine (Satoh et al., 1999). In other studies, leptin has been found to increase SNA, arterial pressure as well as heart rate and to inhibit the baroreflex (Arnold et al., 2009; Mark et al., 2009). Leptin may also have a role in modulating the peripheral chemoreflex at the level of the CNS as microinjection of leptin into caudal pressor areas of the NTS has been found to potentiate the sympathetic and blood pressure responses to chemoreflex activation (Ciriello & Moreau, 2012). These cardiovascular effects may not be debilitating under normal homeostatic conditions, however in conditions of increased circulating leptin, such as in OSA and obesity, the cardiovascular responses may be detrimental."

This study shows the increase in the expression of leptins like Ob-Rb in Carotid .

Images: Fluorescent (a-c) photomicrographs showing the effect of IH on Ob-Rb (a) and ERK 1/2 (b) expression in carotid body glomus cells. Note that Ob-Rb and ERK 1/2 are co-expressed in the same cells (c). Calibration mark in (a) represents 100 μm and applies to (a-c).
Images: Western blots showing the presence of Ob-Rb (a) and Ob-R100 (b) in carotid bodies after IH. Note that IH significantly (*) decreases the protein level of Ob-Rb (a), while significantly (*) increasing the protein level of Ob-R100 (b) compared to normoxic controls (b). p values are indicated. n=5-6.

This study will give the reader great insights on the molecular biology of OSA. Check it out:

Saturday, May 11, 2013

Tissue Acidosis and Inflammation Related Nociceptive Pain

Important Implications for Inflammatory Pain States

Inflammatory pain is often accompanied by a drop in pH (Acidosis). Here investigators hypothesized that modest drops in extracellular pH leading to calcium fluxes acts like a dynamic switch to rapidly mobilize trkA to the cell membrane surface of adult sensory neurons, which in turn serves to increase the sensitivity of these neurons to NGF. The findings reveal a cellular mechanism whereby even small changes in pH can rapidly shift sensitivity to a critical driver of the inflammatory pain state—NGF. They way they demonstrate this shift is quite ingenious: Geoffrey E. Bray, Zhengxin Ying, Landon D. Baillie, Ruiling Zhai, Sean J. Mulligan, and Valerie M.K. Verge. Extracellular pH and Neuronal Depolarization Serve as Dynamic Switches to Rapidly Mobilize trkA to the Membrane of Adult Sensory Neurons. The Journal of Neuroscience, 8 May 2013, 33(19):8202-8215; doi:10.1523/JNEUROSCI.4408-12.2013.
Images: NGF-responsive adult sensory neurons have a large cytoplasmic pool of high-affinity NGF receptors. Six micrometer cryostat sections of L5 DRG processed for high-affinity NGF binding (left) or trkA immunohistochemistry (right) reveal a large cytoplasmic pool of proteins that are able to bind 20 pm radio-iodinated NGF with high affinity or that are immunoreactive to trkA-selective antibodies. Scale bar, 20 μm.

Here're images showing the pH Related switch and rapid migration of TrkA to the membrane

Images: Acidic pH challenge rapidly mobilizes trkA to the membrane from internal stores. A, Bar graphs summarize relative changes in neuronal cell-surface trkA expression from three separate experiments (detected with immunofluorescence) over neurons exposed to control (pH 7.4) or acidic (pH 6.5) media for 30 min with or without exposure to Golgi collapsing compound BFA and as normalized to the mean signal intensity from the control pH group. Note: A significant increase is observed in the mean levels of trkA mobilized to the neuronal membranes of sensory neurons in response to acidosis when compared with the control pH, a response that is blocked with BFA treatment. B, Immunofluorescence photomicrographs and summary histograms (C) depict degree of FM 1–43FX-stained neuronal membrane internalization in response to conditions as indicated. Note: Significant membrane internalization was only observed in the NGF challenge control group and not in response to acidic pH challenge with or without BFA treatment. (Data normalized to the control pH of each experimental condition and pooled from three separate experiments; A, C, one-way ANOVA with post hoc Tukey's, **< 0.01; ***< 0.001). Scale bar, 20 μm.

The heightened level of trkA activation likely has ramifications on both short- and long-term sensitization processes as it regulates the activity and expression of a wide variety of receptors, ion channels, and signaling molecules (Mantyh et al., 2011). In the short term, it modulates the activity of receptors and ion channels. For example, NGF decreases the threshold of activation of the nociceptive transient receptor potential vanilloid 1 (TRPV1) receptors (Chuang et al., 2001), mediates TRPV1 trafficking to the membrane (Stein et al., 2006), increases purinergic receptor P2X3-mediated currents and Ca2+ transients (D'Arco et al., 2007) and for sympathetic neurons, rapidly modulates the activity of at least four voltage-gated currents (Luther and Birren, 2009). In the long term, increased NGF can lead to increased transcription of many nociception-associated genes such as its receptors trkA and p75 (Verge et al., 1989, 1992); the neuropeptides Substance P, calcitonin gene-related peptide (Lindsay and Harmar, 1989; Verge et al., 1995), and PACAP; Jongsma Wallin et al., 2001, 2003); sodium channels (Dib-Hajj et al., 1998; Fjell et al., 1999; Kerr et al., 2001); and P2X3 (Ramer et al., 2001; Simonetti et al., 2006). It is also interesting to note that activation of trkA was linked in our study to a parallel activation of p38MAPK, which has been shown to be linked to NGF-mediated increases in ASIC3 expression during inflammation (Mamet et al., 2003).

Related Reagents:
All Trk Antibodies
Neurotrophin Antibodies
Neurotrophin Proteins
Primary Neurons and Astrocytes-Primary human, rat and mouse neurons and astrocytes by Category


Tuesday, May 07, 2013

More on the Neurobiology of Itch

I have an earlier posting on neuro-transmission of itch or pruritis. This focused on the role of Toll-like Receptor 3 (TLR 3). This posting looks at the role of Gastrin-Releasing Protein (GRP) and the Gastrin-Releasing Protein Receptor (CRPR) in chronic itch. The findings are important because this condition affects millions worldwide and results in a costly erosion of quality of life.

Here chronic itch was studied in Macque Monkeys over a period of 4 years. The expression patterns of GRP, GRPR and PGP9.5 were accessed by immunohistochemistry: Leigh A Nattkemper, Zhong-Qiu Zhao, Anna J Nichols, Alexandru D P Papoiu, Carol A Shively, Zhou-Feng Chen and Gil Yosipovitch. Over-Expression of the Gastrin-Releasing Peptide in Cutaneous Nerve Fibers and its Receptor in Spinal Cord in Primates with Chronic Itch. Journal of Investigative Dermatology accepted article preview 4 April 2013; doi: 10.1038/jid.2013.166.
Images: Double labeling of PGP9.5 and GRP in skin of primates representing mild, moderate and severe itch. Primates with higher scratching severity showed in increase in the co-localization of PGP9.5 and CRP at the dermal-epidermal junctions (arrows).

In addition to increased PGP9.5/GRP expression in the skin, similar results were shown for expression of GRP/GRPR in DRGs. This makes GRP and its receptor candidate drug targets for chronic itch or pruritis in humans.