The IndEx-2 system evaluates antigen density and activation thresholds to address on-target, off-tumour side effects in antibody-targeted therapies. This system controls the expression of one or two proteins over a dynamic range, linking antigen density to activation thresholds for cytolysis and cytokine release. This innovative approach supports screening, characterisation, and lead selection for mono- and dual-targeted therapies.

Titratable expression of one or two antigens with a large dynamic range.

The utility of the system is characterised by three key attributes:

• Inducible expression of antigen(s): A cell line system that allows the expression of one or two antigens of interest, in a finely titratable manner and with large dynamic range of expression.
• Functional assays:  A suite of functional assays utilising high content readouts, employing a well-characterised donor pool or even patient material.
• Threshold determination: An analysis methodology that enables the determination of activation thresholds.

The IndEx-2 assays system is a robust in vitro model to evaluate the influence of antigen expression levels on a targeted therapeutic’s efficacy and safety. This versatile tool enables the controlled expression of one or two antigens of interest, and uniquely allows for the estimation of antigen expression thresholds required for therapeutic activation.

We utilise the royalty-free MAD7 CRISPR nuclease, enabling us to generate bespoke knockout or knock in cell lines for our customers. Such gene edited cell lines can be combined with our other technologies, such as the inducible IndEx-2 system, allowing the creation of cell line in a relevant background with inducible expression of the target antigen of interest.

RoukenBio offers custom reporter cell lines to fit the needs of your specific assays, including bioluminescent and fluorescent reporter cell lines, checkpoint blockade reporters (such as PD-1/PD-L1 blockade) as well as fully artificial reporter systems that can be used to monitor the activation of receptor tyrosine kinases or G protein coupled receptors (GPCRs). We have a diverse range of ready to go reporter cell lines, ready to be utilised in assays in-house at RoukenBio, or be shipped to your facility for use in your own assays.

Reporter system engineered into HEK293 generated HEK STAT6 RE cells shows a dose-dependent IL-13 response.

Our in-house expertise in the design and generation of bespoke target expressing recombinant cell lines provides you with the best possible cell line for your specific needs. We also have an ever-growing collection of pre-developed target-expressing cell lines engineered to express specific targets of interest for drug screening and validation studies.

Engineered target cells were opsonised with an antibody drug molecule and incubated with cryopreserved PBMCs to determine ADCC activity as compared to a reference standard.

We have expertise in the utilisation of expression attenuation techniques to create recombinant stable cell lines with defined levels of expression of your target antigen(s). These cells lines can be used in vitro for modelling the expression levels of tumour associated target antigens found in both healthy and diseased tissues and used in in vivo mouse models, for investigating the effect of tumour cell target antigen density on the efficacy and safety profile of a therapeutic. 

Our cell line development experts have experience and expertise in the design of 1^st to 4^th generation chimeric antigen receptors (CARs). We have predeveloped protocols for the generation and expansion of CAR expressing primary αβ and γδ T cells. We also have in-house developed Jurkat NFAT luciferase reporter cell lines that can be used as a background for CAR expression. These primary or Jurkat CAR-T cells can be utilised as effector cells in our suite of functional assays.