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…]
We previously addressed the PD-1:PD-L1/PD-L2 immune inhibition and the corresponding cell-based tools to screen immuno-oncology agents for restoring antitumor immune response. Unfortunately cancer cells have other ways to escape and survive. Let’s look together at another immune inhibition pathway, namely the TIGIT:CD155/CD112.
As messenger RNAs (mRNAs) are easier to deliver into cells then plasmids or viral vectors, they are useful for non-dividing cells. Inversely to the vectors, they ensure genome integrity that is recommended for cell therapeutics. mRNA are also well adapted to transient expression as required for cellular reprogramming, gene editing, and vaccines.
You might like to take a look at this poster, presented by Trilink (renowned modified nucleic acid experts) at the Keystone symposia last March (Pattern Recognition Signaling: From Innate Immunity to Inflammatory Disease). They share results on how to optimize messenger RNA for therapeutic activity.
“Innate Immune focused approaches to maximize messenger RNA therapeutic activity”
Download your copy of the poster here.
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 ELISAs 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 pretty 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, iPSC cell lines have emerged as new cellular models. The development of 3D 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 project.
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…]
In a recent paper, Horita H. et al. identified a set of novel Post-Translational Modifications (PTMs) of the protein Programmed Cell Death Ligand (PD-L1).
For this, a novel series of PTM enrichment assays enabling the highly specific profiling of 4 key PTM profiles (Tyrosine phosphorylation (pY), Acetylation (Ac), Unbiquitination (Ub) and SUMOylation 2/3), have been used on EGF-stimulated A431 cell line. They revealed that EGF induced pY, Ac, mono- and poly-Ub Of PD-L1 in these EGF treated epidermoid carcinoma cells. The authors also suggested that the balance between mono- / poly-Ub of PD-L1 might regulate PD-L1 stability, as already described with LDB-1 protein.
These novel PD-L1 PTMs and their related regulatory actions might be valuable information in the future for the design of drug strategies targeting PD-L1/PD-1 immune checkpoint inhibition. [Read more…]
One of the biggest challenges as a researcher in life sciences, is to obtain proof of concept the more predictive as possible. To help you to reach your objectives, many innovative tools are being developed and new techniques are emerging.
In this post, I’d like to essentially focus on two innovative cell culture devices which mimic in-vivo conditions in in-vitro systems, in fields such as 3D cell culture, Microfluidics and Oriented cell culture. [Read more…]
Stauprimide is known to prime Embryonic Stem Cells (ESC) by targeting the c-Myc-activating transcription factor NME2. Its mechanism of action is linked to the inhibition of the nuclear localization of NME2 leading to the downregulation of the transcription of the c-myc oncogene.
In a recent study, Bouvard C. et al. evidenced that Stauprimide’s mechanism of action could also be used to pharmacologically targetc-myc transcription in cancers. [Read more…]
For more than 2 years now, the Silicon Rhodamine-like (SiR) technology has allowed the live cell imaging field to evolve significantly.
Fluorescent SiR-probes have appeared as the best alternative tools for studying Actin (SiR-actin), Microtubules (SiR-Tubulin), DNA (SiR-DNA) and now lysosome (SiR-Lysosome) for live cell imaging. Who better to show this? Well, here’s how other researchers have been using them to get optimal results. [Read more…]