A single-domain antibody (sdAb, also called Nanobody) is an antibody fragment consisting of a single monomeric variable antibody domain. Like a whole antibody, it is able to bind selectively to a specific antigen. With a molecular weight of only 12–15 kDA, single-domain antibodies are much smaller than common antibodies (150–160 kDa). They have been shown to be just as specific as a regular antibody and in some cases more robust. They are being researched for multiple pharmaceutical applications in in vivo imaging and targeted therapy. eg. the fusion of a fluorescent protein to a single-domain antibody can be used to trace targets in different compartments of living cells. They can therefore increase the possibilities of live cell microscopy and will enable novel functional studies. [Read more…]
Sekisui XenoTech has just been issued U.S. Patent No. 9,642,355 for the “cryopreservation of cells and subcellular fractions,” specifically related to Sekisui XenoTech’s CryostaX® test systems. This hepatocyte cryopreservation method was invented by Maciej Czerwinski, Ph.D., Director of Consulting for Sekisui XenoTech. [Read more…]
The mitogen-activated protein kinase (MAPK) signaling pathway is activated by a number of extra and intracellular stimuli including cytokines, growth factors, and hormones as well as stressors such as oxidative and ER stress. This pathways plays a key role in the regulation of many cellular processes including proliferation, differentiation, the stress response, motility, growth, differentiation, survival, and death. Abnormal MAPK signaling may contribute to increased or uncontrolled cell proliferation and/or resistance to apoptosis. To study this complex pathway, several tools are available, from the pathway specific arrays for an initial screen, to phospho-specific ELISA tests for individual target validation. This post aims at helping you to easily identify tools to explore this pathway in your samples (from arrays to phospho-ELISAs). However, I could not start without showing you once more one of these eye-catching illustrations of cell signalling pathways. I’ll let you explore it to dig out the MAPK protein cascade among all of them (a kind of Where’s Wally for the researcher !).
Since the discovery of reprogramming factors in 2006 and the boom of CRISPR gene editing strategies, induced pluripotent stem cells (iPSC) have emerged as new cellular models. The development of 3D cell culture technologies has also contributed to the generation of induced Pluripotent Stem Cell (iPSC) derived cells, with unique applications from patient-specific drug responses testing, to regenerative medicine. I would like to introduce in this post a selection of reagents in this domain, a combination of both routine and innovative quality reagents, that I consider as bringing something extra to your stem cell research projects.
In a previous post dedicated to Quantitative arrays (Quantibody), I introduced our L-Series aimed at a broad one shot profiling of up to 1000 markers at once. This relative quantitation technology allows you to perform a first screen of your samples of interest versus a control, before you go on to targeted profiling using either pathway specific arrays, or a custom array including the targets of interest identified with the initial L-series screen. [Read more…]
On your journey to Biomarker profiling, you will reach the point where you need to quantify the proteins of interest identified along the way (eg. validation of semi-quantitative array results; biomarker discovery with an initial hunch on which pathway is involved).
At this stage, you will have narrowed down the number of targets you want to look at. However, the use of ELISAs is likely to be still too costly, too time consuming, and may require too much sample volume. [Read more…]
Progesterone derived Allopregnanolone (ALLO) is an extensively studied neurosteroid that has been shown to be involved in neurodegenerative diseases, including Alzheimer’s, Parkinson’s disease, and multiple sclerosis. It is also linked to neuroinflammatory processes through a beneficial action on pro-inflammatory cytokines.
Allopregnanolone detection kits based on polyclonal antibodies were already available through Arbor Assays (K044-H and K044-C), a specialist of immunassay kits, with a special focus on inflammation and reproduction targets.
A new Allopregnanolone EIA kit has just been released, based on a monoclonal antibody (K061-H1). In addition to the supply stability offered by the monoclonal antibodies, this new kit is more sensitive than the original one, it requires smaller sample volumes and provides increased signal. It also has a more favorable cross reactivity profile: [Read more…]
These cell lines transiently express the current FDA and EMA recommended SLC drug transporters (eg. OCT1 and OCT2; OAT1 and OAT3; MATE1; MAT2K…). Conditioned as cryopreserved format, they provide flexibility for experimental planning and can be assayed in just 2 days.
The JAK/STAT pathway is an important signalling process for numerous cytokines and growth factors.
Its activation is essential to many processes such as hematopoiesis, immune development, growth, adipogenesis, mammary gland development… [Read more…]
Human and Animal Dermal S9 Fractions now available as standard products
Subcellular fractions are widely used in drug discovery and preclinical drug development to evaluate the in vitro metabolism of new therapeutics. Skin fractions are already available from tebu-bio as catalogue items for CD1 Mouse and IGS Sprague Dawley Rat.