Johan Duchêne

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Apolipoprotein E antibody screening by Western Blot on culture media. HAP1 WT and APOE KO were cultured in serum free media. Media were collected, concentrated, and 30 μg of protein were processed for Western Blot with the indicated Apolipoprotein E antibodies. The Ponceau stained transfers of each blot are shown. Antibody dilutions were chosen according to the recommendations of the antibody supplier. Exceptions were given for antibodies ab1907*,13366**,18254-1-AP, MA5-15852* and 66830-1-Ig* which were titrated to the concentrations listed below, as the signals were too weak when following the supplier’s recommendations. Antibody dilutions used: GTX635889* at 1/200, GTX635891* at 1/200, ab52607** at 1/200, ab51015** at 1/1000, ab1907* at 1/200, 13366** at 1/500, ARP54283 at 1/1000, 701241** at 1/200, MA5-41148** at 1/200, MA5-15852* at 1/200, MAB41441* at 1/200, NB110-60531* at 1/200, 18254-1-AP at 1/200, 66830-1-Ig* at 1/200. Apolipoprotein E predicted band size: 36 kDa. *Monoclonal antibody, **Recombinant antibody.

APOE plays a key role in cardiovascular and Alzheimer’s disease.

Reliable tools are needed to study its expression and function.

Among 14 antibodies tested, 4 showed excellent performance.

Pick up the right one.

Report: f1000research.com/articles/12-...
Data summary: onlygoodantibodies.co.uk/28/

YouTube video by Antibody Validation Antibody Validation as a Scientific Discipline: Lessons and Challenges from YCharOS - Carl Laflamme

Here is Laflamme's presentation on Antibody Validation as a Scientific Discipline.
www.youtube.com/watch?v=c0Oc...

The antibodies don’t work! The race to rid labs of molecules that ruin experiments Poorly performing antibodies have plagued biomedical sciences for decades. Several fresh initiatives hope to change this.

The antibodies don’t work! The race to rid labs of molecules that ruin experiments

Poorly performing antibodies have plagued biomedical sciences for decades. Several fresh initiatives hope to change this.

www.nature.com/articles/d41...

Many articles reported using an antibody ... that didn’t even bind the key protein in Laflamme’s testing. Those articles had been cited over 3,000 times.

A key question is:

◼️ 𝐂𝐚𝐧 𝐩𝐫𝐨𝐭𝐞𝐢𝐧 𝐛𝐢𝐧𝐝𝐞𝐫𝐬 𝐚𝐜𝐡𝐢𝐞𝐯𝐞 𝐡𝐢𝐠𝐡 𝐬𝐩𝐞𝐜𝐢𝐟𝐢𝐜𝐢𝐭𝐲 𝐟𝐨𝐫 𝐞𝐯𝐞𝐫𝐲 𝐞𝐩𝐢𝐭𝐨𝐩𝐞 & 𝐩𝐫𝐨𝐭𝐞𝐨𝐟𝐨𝐫𝐦?

Some investors assume an answer.

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Analysis of 16 C9ORF72 antibodies by immunoblot. Cell lysates from HEK-293 parental, heterozygous (+/-) or two individual C9ORF72 KO clones (KOA, KOB) were prepared and processed for immunoblot with the indicated C9ORF72 antibodies. The arrows point to positive C9ORF72 signals. The Ponceau stained transfers associated with each blot are shown as a protein loading control. More details: https://doi.org/10.7554/eLife.48363

ALS is a neurodegenerative disease
C9ORF72 mutation is common
Understanding its biology is key

Laflamme 2019 (10.7554/eLife.48363) showed:
👉Most antibodies were non-specific
👉Specific ones never used

Since then:
❌ Sc-138763: discontinued
✅ Specific ones (GTX634482,GTX632041, ab221137): adopted

Nobel Prizes This Year Offer Three Cheers for Slow Science

'All three awards (...) honored achievements rooted in fundamental research from decades ago. Some experts interpret the selections by the Royal Swedish Academy of Sciences as representing the importance of slow, basic science, work pursued out of a desire to better understand the world.'

Here is the Antibody Characterization Report for E3 ubiquitinprotein ligase parkin (Parkin)
zenodo.org/records/5747...

More reports are found here: ycharos.com/data/

Indeed !

Yes the website is super new and will be updated every month with new antibodies.

Accueil / Home YCharOS Inc. YCharOS Inc. est une entreprise canadienne d’intérêt public, dont la mission est de caractériser les anticorps commerciaux disponibles pour chaque protéine humaine, tout en suivant les pr...

Sorry to hear that OGA website does not work at Memorial Sloan Kettering.
Maybe try this ycharos.com
All data are available here too, but it is more tedious as you would need to download a report for each protein.

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Parkin antibody screening by immunoblot. Lysates of SH-SY5Y (WT and PRKN KO) were prepared and 50 μg of protein were processed for immunoblot with the indicated Parkin antibodies. The Ponceau stained transfers of each blot are shown. Antibody dilution used: 702785 at 1/200; 711820 at 1/200; 39-0900 at 1/500; ab77924 at 1/200; ab15954 at 1/500; 14060-1-AP at 1/1000; MAB1438 at 1/250; MAB14381 at 1/500; GTX39745 at 1/1000; GTX65811 at 1/1000. Predicted band size: 52 kDa. Which antibody should you choose then?

PARKIN labels damaged mitochondria for recycling
No PARKIN → no cleanup → neurodegeneration
Mutations in PARK2 are common in Parkinson’s disease

Accurate detection of PARKIN is crucial

Problem:
The most used antibodies are not selective
In contrast, some very specific antibodies are not used

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⚠️ Half of commercial antibodies miss their target!
So how do you pick the right one for your experiment?

Here’s the solution 👉
Antibody characterization data (all tested in KO cells) are now available at:
🔗 onlygoodantibodies.co.uk

Tested by @ycharos.bsky.social & @oga-community.bsky.social

Scientific objectivity is a myth – cultural values and beliefs always influence science and the people who do it Cultural ideas are inextricably entwined with the people who do science, the questions they ask, the assumptions they hold and the conclusions they land on.

The myth of scientific objectivity hides the truth that every experiment is influenced by cultural values, assumptions and beliefs – and that actually hurts the search for truth

Analysis:
buff.ly/KcLU0bE
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Durable lymphocyte subset elimination upon a single dose of AAV-delivered depletion antibody dissects immune control of chronic viral infection To interrogate the role of specific immune cells in infection, cancer, and autoimmunity, immunologists commonly use monoclonal depletion antibodies (d…

We've also switched from mostly transgenic mouse strains to AAV/retrovirus "transgenes". It cut mouse costs by >50%, and makes our work faster and more responsive to reviewer requests. AAVs can even be used to produce depleting antibodies.

www.sciencedirect.com/science/arti...

Do more with Less: Improving High Parameter Cytometry Through Overnight Staining Recent advances in flow cytometry have allowed high-dimensional characterization of biological phenomena, enabling breakthroughs in a multitude of fields. Despite the appreciation of the unique prope...

You can also save money by cutting-costs and preventing waste. We do a low of flow cytometry, and retitrated antibodies for overnight staining, reducing costs ~100-fold while improving signal-to-noise and reproducibility

currentprotocols.onlinelibrary.wiley.com/doi/10.1002/...

Abstract submission and travel grant application for the 9th World Conference on Research Integrity are open. Please consider to submit an abstract and to reshare this message. lnkd.in/eJ9hmaRs

A do-or-die moment for the scientific enterprise Reflecting on our paper “The entities enabling scientific fraud at scale are large, resilient, and growing rapidly”

Today, our article "The entities enabling scientific fraud at scale are large, resilient, and growing rapidly" is finally published in PNAS. I hope that it proves to be a wake-up-call for the whole scientific community.

reeserichardson.blog/2025/08/04/a...

Stimulating immune cells in vitro is a common experimental lab model. We profiled 150K blood immune cells treated with 11 different stimuli to compare the effects. The data are freely available for researchers. See the preprint for our findings and to access the data 🧪 doi.org/10.1101/2025...

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A comparison of mouse vs human tumor microenvironments shows a major difference.

Mouse TMEs have more macrophages, while human TMEs have more T cells.

Chemokine expression patterns are also different.

Learn more: www.biorxiv.org/content/10.1...

#FluorescenceFriday & Erythroblast

Erythroblast stimulated with CXCL12, stained for CXCR4 (green) and nuclei (blue).

Captured via Correlative Light & Electron Microscopy by
@jemimaburden.bsky.social

Learn more: scim.ag/4kTxFZz
@antalpedro.bsky.social
@jffoley.bsky.social
@science.org

In our science.org/doi/10.1126/... we describe the hitherto overlooked erythroblast expression of CXCR4, which do not migrate in response to CXCR4 ligation by CXCL12. Instead, in these cells CXCR4 localises to the nucleus and mediates alternative cell responses in maturation and triggers enucleation

Intracellular and nuclear CXCR4 signaling promotes terminal erythroblast differentiation and enucleation CXCL12-stimulated intracellular and nuclear CXCR4 signaling mediates erythroblast enucleation to generate red blood cells.

With the right link:
www.science.org/doi/10.1126/...

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Intracellular and nuclear CXCR4 signaling promotes terminal erythroblast differentiation and enucleation CXCL12-stimulated intracellular and nuclear CXCR4 signaling mediates erythroblast enucleation to generate red blood cells.

Not all chemokine signaling is about cell migration!

In mouse erythroblasts, CXCL12-bound CXCR4 enters the nucleus to control gene transcription, trigger calcium bursts, and drive red blood cell formation—especially enucleation.

www.science.org/doi/10.1126/...

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