Dimitri Szymczak, PhD

Innovative CleanTag technology provides clean and low input small RNA-seq library

13/10/2017 By Dimitri Szymczak, PhD Leave a Comment

Exploring small RNA transcriptome, a key challenge

Small RNA are involved in numerous biological process and linked to a wide range of conditions. For example miRNA can be used for detection of cancers from blood samples and are used for cancer classification. They are involved in the regulation of the messenger RNA translation.

Small RNA transcriptome is a vast world rich in information. There not only miRNA but other small RNA that can also be used for diagnostics. For example, Repetto et al in 2015 (doi: 10.1186/s12916-015-0489-y) discovered novel small RNA in blood, s-RNY1-5p as a diagnostic biomarker for atherosclerosis-related diseases. The authors used small-RNA sequencing with the innovative CleanTag technology.

[Read more…]

Biomolecule conjugation – how to biotinylate with reproducible results?

13/10/2017 By Dimitri Szymczak, PhD Leave a Comment

Biomolecule conjugation is critical to many applications such as bead-based assays, ELISA and chromatography by affinity. Unfortunately the classical methods are known to be tedious and with low efficiency. Trilink Biotechnologies has come this year with the solution, an innovative chromophore-linker-based conjugation chemistry called ChromaLink. [Read more…]

CleanCap technology – the new era for mRNA capping has come

12/10/2017 By Dimitri Szymczak, PhD Leave a Comment

Capping is a required protection in 5′ of the mRNA that is necessary for biological activity and stability into the cells. There are already several methods of capping using mCap, ARCA or enzymatic methods. Unfortunately, they are limited in efficiency (such as mCap and ARCA), and can be costly (such as the enzymatic methods). Trilink Biotechnologies, the modified nucleic acid experts, have developped a new, far more efficient technology called CleanCap available in Europe via tebu-bio. [Read more…]

Simple and effective CRISPR CAS9 gene editing for primary cells

12/10/2017 By Dimitri Szymczak, PhD Leave a Comment

Vector-free CRISPR-CAS9 gene editing to accelerate therapeutic applications

A few years ago, Ayal Hendel et al (doi:10.1038/nbt.3290) published results revealing that chemical alterations to sgRNA enhance gene editing in primary cells. To demonstrate this, Matthew H Porteus’s team chose the targeted genes CCR5, HBB and IL2RG respectively involved in anti-HIV clinical trials, cell anaemia and thalassemia, and severe combined immunodeficiency. More recently, the same team tested several modified CAS9 mRNA. You can find the practical results on this poster introduced at the ASGC. [Read more…]

Analysis tool for direct and sandwich ELISA – convenient and reliable

11/07/2017 By Dimitri Szymczak, PhD Leave a Comment

Many ELISA kits – one analysis tool

Analyte quantification (in pg/ml or ng/ml) such as IL-6, TNFalpha and numerous other proteins is conveniently performed with immunoassays called ELISA kits. At tebu-bio, we not only provide more than 10 000 ELISA kits but we also support researchers through our techserv team who are on-hand to suggest the best kits and to answer any questions.

Being part of that team, I have noticed a number of often asked questions that can be resumed in one : What is the best method for data analysis? [Read more…]

Optimizing the CAS9 messenger RNA for vector-free gene editing

28/06/2017 By Dimitri Szymczak, PhD Leave a Comment

Sequence engineering and chemical modification of CAS9 mRNA

Cas9 Western Blot in CD34+ cells - Trilink poster "“Maximizing Translation of Cas9 mRNA Therapeutics by Sequence Engineering and Chemical Modification”"

Extract from poster “Maximizing Translation of Cas9 mRNA Therapeutics by Sequence Engineering and Chemical Modification”.

For transgenesis and therapeutic perspectives, vector-free delivery of the CAS9 for gene editing is highly preferable. It avoids the risk of hitting the genome due to the vector integration. Directly using CAS9 mRNA is a top option.

Furthermore, as a new promising class of therapeutic biologics, messenger RNA are the subject of numerous studies.

This year, Matthew Porteus’s and Trilink’s teams revealed key and practical results at the ASGC with a poster you can download below.

Notably, there is a large screen of the mRNA CAS9 modifications based on the indel formation. This interesting comparison includes also CAS9 RNP and reveals the high performance of the CleanCap U-depleted 5-moU CAS9 mRNA. We can also note that for the CleanCap CAS9 mRNA HPLC purification is not required.

“Maximizing Translation of Cas9 mRNA Therapeutics by Sequence Engineering and Chemical Modification”
Download your copy of the poster here.

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Stable Cas9-expressing cell lines

21/06/2017 By Dimitri Szymczak, PhD Leave a Comment

Shen et al (Nature Methods, 2017) explore and identify synthetic interactions among 73 cancer-associated genes. To perform their loss of function screen they combined CAS9-expressing cell lines with a sgRNA library of high titer lentiviral particles. Most of these gene interactions were subsequently validated by drug treatment. [Read more…]

New TIGIT:CD155 cell-based assay to restore immune response

23/05/2017 By Dimitri Szymczak, PhD Leave a Comment

TIGIT:CD155/CD112 immune inhibition (in green)

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.

[Read more…]

Maximize messenger RNA therapeutic activity with innate immune focused approaches

17/05/2017 By Dimitri Szymczak, PhD Leave a Comment

Messenger RNAs – a promising class of new therapeutic biologics

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.

Proteins with the High Purity (HiP™) label make the difference

07/03/2017 By Dimitri Szymczak, PhD Leave a Comment

The HiP™ (High Purity) distinction by BPS Bioscience starts, of course (as the name says), with a high purity level. But that’s not enough. Such pure proteins may aggregate, which is not compatible with binding assays. Thus, the HiP™ label also demands a low level of aggregation, or even none at all. [Read more…]