The studies presented here demonstrate the potential of the single-molecule solutions offered by LUMICKS’ C-Trap in the study of RNA virus replication.
Performing single-molecule experiments, the researchers uncovered two opposing and significant roles of RNA binding proteins. Zimmer et al. provided direct
evidence that the RNA-binding protein ZAP-S directly impacts the SARS-CoV-2 1a/1b frameshifting and can thus inhibit viral replication [1] – a discovery that
could lead to the development of novel Coronavirus treatments. Contrarily, Hill et al. showed that accumulation of protein 2A in host cells can lead to increased
viral protein translation through RNA binding [2], allowing for the development of RNA therapies that could help treat encephalomyocarditis.
The success of chimeric antigen receptor (CAR) T cell therapy for hematological malignancies has not yet translated into long-term elimination of solid tumors, indicating the need for adequate tuning of CAR T cell functionality. The CAR binding moiety is the critical trigger for CAR T cell signaling. CAR binding affinity alone does not determine T cell effector functions. In a panel of anti-Her2 CARs covering a 4-log affinity range, we observed that rather high affinity and cell avidity above the minimum threshold, combined with elevated tonic signaling, produce adequate T cell capacity for expansion and tumor control. The same scFv mutations increased both antigen-specific affinity, cell avidity, and antigen-independent tonic signaling; above a minimum threshold, raise in affinity translated into cell avidity in a non-linear fashion. In this case, replacement by amino acids of higher hydrophobicity within the scFv coincidentally augmented affinity, non-specific binding, spontaneous CAR clustering, and tonic signaling, all together relating to T cell functionality in an integrated fashion. Data highlight the mechanistic complexity of CAR signaling and suggest inclusion of additional variables, for example, hydrophobic interactions, into the equation when determining the CAR’s antigen-specific and tonic signaling capacities.
Translocations involving FGFR2 gene fusions are common in cholangiocarcinoma and gastric carcinoma and predict response to FGFR kinase inhibitors. However, response rates and durability are limited due to the emergence of resistance, typically involving FGFR2 kinase domain mutations, and to sub-optimal dosing, relating to adverse drug effects.
This webcast will present new work showing that the vast majority of such alterations retain the extracellular domain (ECD), potentially enabling highly selective targeting of the FGFR2 ECD using biotherapeutics.
To improve on the activity of traditional bivalent monotopic antibodies, the Sellers lab systematically generated biparatopic antibodies targeting distinct epitope pairs in FGFR2 ECD, and identified antibodies that effectively block signaling and malignant growth driven by FGFR2-fusions.
These antibodies robustly blocked proliferation and colony formation in FGFR2-fusion driven cholangiocarcinoma and demonstrated robust in vivo anti-tumour activity. In vivo activity was marked by significant antibody-mediated downregulation of FGFR2 and in turn this was associated with robust lysosomal internalization enacted by the two biparatopics. In vitro, the biparatopic antibodies demonstrated activity against FGFR inhibitor resistant alleles of FGFR2. The internalization properties of the antibodies also make them suitable for exploration as antibody-drug conjugates
Commercial CAR-T therapies still suffer from severe limitations, as majority of patients fail to achieve complete response and ultimately relapse.
Watch this Webinar to discover Prof. Marco Ruella’s team have adopted a novel CAR-T avidity screening method to improve safety and exhaustion profile, leading to 100% clinical response in a phase I trial.
Acute myeloid leukemia (AML) continues to be an unmet clinical need for both adult and pediatric patients. Although CAR-T cell therapy has demonstrated substantial therapeutic potential, further advancements are necessary to achieve safe and lasting disease remission. In this webinar, CAR-CIK cell pioneer Dr. Sarah Tettamanti, from the Tettamnti foundation in Milan, Italy (alongside our Lead Product Manager, Shira Segal, at LUMICKS) discuss how Cell avidity was used to generate an additional layer of information to understand the mechanism of action and enhance decision-making on identifying the most efficacious candidates whilst limiting toxicity to healthy cells.
T cells play a pivotal role in tumor immunosurveillance. Multispecific cell engagers (CEs) have been adopted in the field of immuno-oncology to redirect T cells toward cancer cells, thereby unleashing the anti-tumor potential of the patient’s immune system. CE-mediated cell binding induces T cell activation and the formation of an immunological synapse, which is a prerequisite for effective tumor cell lysis.
The strength of the initial binding events between a T cell and a tumor cell dictates the efficiency of the anti-tumor response. Assessing cell avidity, i.e. the total intercellular interaction strength between two cells, gives crucial insights into the efficacy of CEs as anti-tumor therapeutic agents.
Here, we deploy LUMICKS’ high throughput avidity measurement (HTAM) technology to measure CE-induced cell avidity in a high throughput manner. We demonstrate the assay performance characteristics, i.e. specificity, precision, and range, via CE titration experiments in the context of a Jurkat T cell model system. We find that the HTAM CA assay is suitable for candidate screening in high throughput, with high sensitivity and precision.
T cell receptor (TCR) -based cancer immunotherapy has the potential to become a powerful approach to treat solid tumors, such as melanoma. However, conventional methods that validate the effectiveness of TCR transduced T cells are often inconsistent with functional assays or are tedious to perform. In this application note, we show how the z-Movi® Cell Avidity Analyzer reliably and quickly identifies functionally optimal TCR-engineered T cells targeting melanoma cell lines based on cell–cell interaction strength (cellular avidity).
Identifying effective immunotherapeutic treatment strategies for multiple myeloma that also mitigate relapse often requires tedious and time-consuming validations, such as cell-killing assays and in vivo engraftments. We show that intercellular binding strength (cell avidity), measured by the z-Movi® Cell Avidity Analyzer, quickly predicts CAR T-cell efficacies that correlate with treatment outcomes in vivo.