The importance of antibodies as tools in scientific research studies cannot be understated, yet these reagents have increasingly come under fire for their lack of reproducibility. Part of the issue is that the antibody market is composed of hundreds of vendors and resellers with varying definitions for validation and consistency. Cell Signaling Technology (CST) believes that antibody suppliers should be held accountable for the products they provide, but that vendors alone cannot solve the reproducibility “crisis." How antibodies are validated and used in the laboratory is a critical component to this process. Researchers need to be more attentive to following established protocols and leverage the expertise of the scientists who have developed and tested the product they are using. Journals need to be more active in enforcing existing policies regarding materials and methods or develop more clear-cut means to identify and describe the use of biological reagents in published research. During this webinar we will address the role vendors, researchers, and journals should play in minimizing irreproducibility. We will also outline CST’s antibody validation process, while highlighting steps all users should consider when selecting and using antibodies in their research.
It's hard to believe that another year is almost over. We hope you're having a lovely holiday season with you and yours. We've been fairly busy closing another quarter. But it hasn't been all business. 'Tis the season for a little nonsense to fill us all with good cheer! We couldn't think of a better way than putting on some ugly sweaters and rocking the cafeteria.
Topics: Just for fun
Webinar | Validation of a Glycosylation-Independent Antibody Against the Cancer Stem Cell Marker CD133
The cancer stem cell hypothesis postulates that a population of self-renewing tumor-initiating cells, termed Cancer Stem Cells (CSCs), may be responsible for driving tumor heterogeneity, metastasis, therapeutic resistance and/or tumor relapse. Tools to identify and characterize putative CSCs are therefore of significant value for the cancer research community. CD133 is a 5- transmembrane (5-TM) cell surface glycoprotein that shows elevated expression in putative CSCs from multiple tumor types. Numerous studies have used antibodies directed against CD133 to isolate putative CSCs for characterization, in vitro culture, transplantation and drug discovery studies. However, the most commonly used antibodies used to study CD133+ CDCs are raised against glycosylated CD133 epitopes; this is problematic because the glycosylation status of CD133 varies in response to environmental conditions (e.g., hypoxia) or cell differentiation status.
Webinar | Post-translational Modification: Antibody Enrichment for Mass Spectrometry-based Proteomics
PTMScan Proteomics: Identification and Quantification of Post-Translationally Modified Peptides
Protein post-translational modifications (PTMs) regulate all aspects of cellular growth, development, and disease biology. Proteomic analysis of these PTMs has become central to gaining a better understanding of cellular signaling. Current proteomic methods and instrumentation allow for identification of thousands of peptides in a single experiment. PTMScan proteomics from Cell Signaling Technology combine antibody-based enrichment with liquid chromatography-tandem mass spectrometry (LC-MS/MS) for identification and quantitation of post-translationally modified peptides. Products and services are available for analysis of protein phosphorylation, acetylation, ubiquitination, methylation, succinylation, and caspase cleavage from cell lines, tissues, xenografts, or other biological materials (PTMScan Discovery). Services have also been designed for targeted, in-depth coverage of critical signaling pathways (PTMScan Direct). PTMScan methods have been successfully applied to biomarker discovery, drug development, and studies to gain a better understanding of cellular signaling.
Once a year, we slow the centrifuges, quit the cloning, and lose the lab coats, all in honor of relaxation. Our company party gives us a chance to talk about everything outside the lab. We grab a glass of wine or beer and salute the delicious lobsters that fought so bravely. We kick soccer balls and toss Frisbees. We compare notes on sand castle construction.
Topics: Just for fun
Webinar | Highly Multiplexed Single Cell Analysis of Tumor Heterogeneity through Time and Space by Mass Cytometry
The study of the tumor ecosystem and its cell-to-cell communications is essential to enable an understanding of tumor biology, to define new biomarkers to improve patient care, and ultimately to identify new therapeutic routes and targets.
Cancer research is near and dear to our hearts, but so is having a good time. AACR is an annual opportunity to get out of the office and get after both.
Characterize Immune Checkpoint Proteins and T Cell Exhaustion
Using Multiplex IHC
Advances in immuno-oncology have successfully led to novel cancer therapeutics with favorable patient responses that are more durable than conventional cytotoxic chemotherapy (1). However, not all patients respond to immunotherapy; therefore investigators are trying to identify clinically relevant biomarkers with the goal of developing therapeutics based on personalized medicine (2,3).
For those who wish to bring a measure of rationality to the western blot data in the literature, loading controls can induce a fair amount of hand wringing. There are some obvious criteria. First, the protein level of the loading control must not be altered by experimental conditions. Second, the molecular weight of the control must be different from the protein of interest. Third, and most importantly, the signal detected for both the loading control and the protein of interest must be in a linear range, otherwise you’ll find yourself with burnt-out bands that you’ll be unable to quantify.
Topics: Western Blot
Epigenetic modifications to DNA and histone proteins are known to regulate metabolic gene expression, which in turn impacts metabolite levels. Conversely, the machinery responsible for modifying DNA and histones at the epigenetic level is highly sensitive to metabolites arising from cellular metabolism. . .