Lab Expectations

 You are all amped up to run a western blot to identify “your favorite protein.” The lysates have been run and proteins separated by SDS-PAGE. Now it’s time to transfer proteins from the gel to the membrane, and you’re sitting wondering….wet or semi-dry?? Or maybe you are better prepared than I was as a graduate student and you already know your next step, in which case you are aware of the pros and cons of wet and semi-dry transfer.

So your experiments and data are funneling you down an inescapable path. You need to show direct gene regulation by your protein of interest. You think to yourself, “Oh, ChIP...”

You’re gathering data from all your experiments and preparing to present to your advisor and thesis committee at your annual progress report. You have an interesting hypothesis, and you have a validated antibody that recognizes your target protein on a western blot (WB). The molecular weight of the band is correct, and the expression of the target protein changes just the way you predicted it would. Now, you know — and you’d bet the house on it — when that powerpoint slide comes up, someone on your committee is going to ask about loading controls.

The use of multiple antibodies in a single experiment can provide useful information to researchers. Co-staining with multiple antibodies and cellular dyes is a simple, low-content form of multiplex analysis. Techniques for performing multiplex analyses in cells and tissues are powerful research tools that are applicable to general cell biology studies as well as diagnostic purposes. These techniques allow researchers to detect multiple biomarkers to assess their samples. They also allow for easy colocalization studies to determine relationships between analytes. Here we describe two common techniques for fluorescent staining using multiple antibodies in the same assay.

A picture is worth a thousand words, or in the case of immunofluorescent imaging, a thousand proteins. The images used to illustrate a scientific experiment should convey as much information as the text itself. Here at CST, we pride ourselves in the quality of our antibodies and our rigorous validation process. When we approve our primary antibodies for IF, we like to showcase them using high quality images generated in-house. Beyond our recommended IF protocols (check it out here), here are some additional considerations to make when planning your IF staining. 

If you’ve ever transitioned your IHC experiments from a manual protocol to an automated platform, you may have found the conversion process to be a drag. It isn’t an easy thing to do. For that reason, we’re happy to announce our IHC Leadership in Automation initiative. This rigorous validation initiative expands on our already thorough measures, allowing researchers to not only use CST products with our recommended manual IHC protocol, but also to bridge the assay to new platforms and techniques. Our foray into the world of automated IHC aims to reduce the amount of time researchers spend on assay transfer and protocol optimization.

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Traditionally, flow cytometry has been used to identify distinct cell types within a heterogeneous pool of cells, based on extracellular or surface marker expression, an application commonly known as immuno-phenotyping. However, this technology is also readily amenable to intracellular target detection and can be successfully applied to the study of complex signaling events.

This is part two of a two-part series on how to optimize your IHC protocols. Part one introduced the principles behind antigen retrival. Click here if you missed it... but, if you've got your tissue prepped and ready to go, we'll move on to the next steps in the staining protocol.

It’s Friday night and you could be out with your friends right now, but instead you’re tucked away in a dark little room filled with microscopes. Spending the evening in the lab seemed like a good choice at the time because you were certain this immunohistochemistry was going to reveal some small - but important - mystery of the universe to you. But now you’re sitting here, cursing the universe and everyone in it, because all you see when you stare down into the scope is some indistinct fuzziness. And did the controls work - meh - who’s to say? There’s no sugar coating it. It’s a fail.

Part four of a series on immunofluorescence techniques. Check out previous posts on Validation, Experimental Controls, and Fixation/Permabilization. 

After your samples have been prepared, it's time to incubate them with a well-validated antibody, the workhorse of immunofluorescence. If you are a seasoned pro at IF experiments, you are probably used to checking the antibody datasheet (or web page) for the recommended dilution. But have you ever wondered where those recommendations come from?