Advances in Immunoengineering

We developed a flexible human tumour microenvironment 3D cell model platform, adjustable for cellular source and complexity, with comprehensive readouts for antibody specificity and potency.  This breast cancer heterotypic 3D cell culture platform explores microencapsulation in alginate and stirred-tank culture systems. TME components, e.g., fibroblasts and immune cells, were added to tumour spheroids. Proof-of-concept studies evaluated the anti-tumour and immunomodulatory potential of therapies targeting tumour cells and tumour microenvironment.

Monoclonal antibodies and Antibody-drug conjugates (ADCs) are a leading area of targeted cancer therapeutics. In this talk I will discuss novel approaches in antibody design that consider patient immune responses and the tumour immune microenvironment. I will explore antibody target selection and payload combinations directed at pro-tumour mechanisms. Studying cancer immunology and the tumour microenvironment, alongside patient stratification can offer opportunities to harness immune states in cancer and deliver drugs that target cancer vulnerabilities in treatment-resistant solid tumours.

Hypoxia is a key feature of over 90% of solid tumors, and has long been known to play a role in promoting cancer progression and resistance to therapeutic intervention. In this study, we provide an overview of novel strategies to interrogate tumor targeting therapies under hypoxic conditions in 3-D, using robotics-enabled high content imaging. Furthermore, we illustrate how these models could enable novel target identification and validation.

In the post-GWAS era, the HLA region is linked to numerous human diseases. HLA proteins present a complex array of peptides that interact with CD8+ and CD4+ T cells, influencing disease dynamics. The Caron Lab aims to use mass spectrometry and systems immunology to explore the immunopeptidome's role in immune-related diseases and enhance treatments through next-gen immunopeptidomics technologies and collaboration in vaccine design and T-cell immunotherapy.

The microbiome is a complex host factor and key determinant of the outcome of cancer immunotherapy. Its postbiotics are a blend of soluble commensal byproducts that modulate the host environment and can be exploited to predict and improve chimeric antigen receptor (CAR) T cell therapy efficacy. We demonstrate that postbiotics-mediated epigenetic-metabolic reprogramming during CAR T cell manufacturing promotes anti-tumor function and tumor microenvironment resistance in hematologic and solid malignancies.

To identify antibodies specific for tumour-associated Tregs, lymphocytes from tumour-bearing mice were panned against the n-CoDeR phage display library. The antibodies were evaluated for cell specificity, tissue selectivity, Treg depletion, and anti-tumour activity. Deconvoluting the antigens bound revealed both expected and unexpected Treg targets. One antibody bound a distinct epitope on ICAM-1, that was hypothesised to mediate its selectivity towards tumour-associated Tregs. This antibody selectively depleted tumour-associated Tregs, leaving those in the periphery untouched, which was important for anti-tumour effects. These findings support a need for target-agnostic discovery approaches to identify therapeutic antibodies.

IOMX-0675, a fully human antibody antagonises the immunosuppressive receptors LILRB1 and LILRB2 while showing a highly differentiated binding profile towards closely related immune-activating family members, LILRA1 and LILRA3. We describe the selection of IOMX-0675 from our proprietary phage display library and demonstrate that the differential binding profile translates into high efficacy positioning IOMX-0675 as a dual-targeting checkpoint inhibitor with best-in-class potential. The recent CTA approval enables preparing for a FIH study.

INCA33890 is a bispecific antibody targeting TGFbR2 and PD1. It antagonises the TGFb signaling pathway only in cells co-expressing PD-1 and TGFR2, mitigating risks of adverse effects associated with systemic TGFb pathway inhibition. INCA33890 has a higher affinity for PD-1, antagonising the PD-1 axis independently of TGFbR2 co-expression, and can specifically antagonise TGFb and PD-1 signaling in tumours.

One obstacle associated with CAR T cells is their limited controllability after administration to the patient, which becomes particularly problematic in the case of severe toxicities. To be able to control CAR T cell function in vivo, we generated caffeine-responsive molecular switches by using high-end protein engineering. We demonstrate that these switches are clean (i.e. no background activation in the absence of caffeine) and efficiently turned on upon addition of caffeine. Furthermore, integration of these switch modules into CARs yields switchable “CaffCARs”, whose function can be precisely controlled via administration of caffeine. We show that this switch platform is modular, enabling caffeine-dependent regulation of CARs directed against different antigens (including antigens for leukemia, lymphoma and solid tumors). Importantly, these CaffCAR T cells are efficiently activated in response to caffeine concentrations that are achieved in human serum after drinking one cup of coffee. Finally, when we tested our CaffCAR T cells in a lymphoma mouse model in vivo, we observed high anti-tumor potency that could be regulated efficiently via administration of caffeine to the mice. Together, we introduce caffeine-responsive switch modules that enable functional regulation of CAR T cells in vivo with caffeine concentrations that are achieved in human serum after drinking one cup of coffee.