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Beers, S. A.

Publications and source records attributed to Beers, S. A..

3 recordsLinked to original sources

Bispecific Antibody Architecture and TNFRSF Target Selection Determine CD8+ T Cell Differentiation and Anti-tumour Immunity

Tumour necrosis factor receptor superfamily (TNFRSF)-targeting bispecific antibodies (bsAb) enable tumour-localised T cell co-stimulation, yet how antibody architecture and receptor choice govern activity remains unclear. Here we define how bsAb format and TNFRSF target selection shape CD8+ T cell responses and anti-tumour immunity. Using B7-H3 as a tumour-associated antigen, we show that dual-bivalent 2x2 bsAb elicit maximal agonistic activity, whereas the corresponding monovalent 1x1 format is least active. A 2x1 format retaining TNFRSF bivalency but monovalent B7-H3 binding preserves substantial activity, identifying co-stimulatory receptor bivalency as a key determinant of efficacy. Across TNFRSF targets, 4-1BB drives the strongest cytotoxic CD8+ T cell differentiation and anti-tumour response. This superiority is conserved in human T cells and reproduced by cognate ligands, indicating that the observed functional hierarchy reflects receptor-intrinsic biology. Mechanistically, efficacy requires tumour-associated B7-H3 and T cell-dependent 4-1BB signalling. Together, these findings establish general principles linking antibody architecture and receptor biology to co-stimulatory bsAb efficacy and provide a framework for rational design leading to optimal therapeutics.

immunology↗

Leveraging TNFR2 for antitumour immunity: T reg depletion and myeloid reprogramming versus T cell costimulation

Although checkpoint inhibitors have revolutionized cancer treatment, responses are largely restricted to targeting CTLA-4 and PD-(L)1. TNFR2 has been identified as a target of interest, but a lack of understanding of whether agonists or blockers should be used, and whether Fc{gamma}R interactions promote effcacy, has hampered therapeutic antibody development. Here, we engineered two distinct -TNFR2 types: ligand-blocking Fc{gamma}R-engaging versus non-ligand-blocking agonist antibodies. Both showed potent anti-tumor effcacy across multiple syngeneic mouse tumor models and combined effectively with -PD-1. The ligand-blocking antibody depleted intratumoral T regs and reprogrammed the myeloid compartment, directing monocytes towards a pro-inflammatory macrophage and dendritic cell trajectory. Surprisingly, this effect depended on both inhibitory and activating Fc{gamma}Rs. In contrast, the agonist directly co-stimulated T and NK cells, through partially Fc{gamma}R-independent mechanisms. Both antibodies converged on activating tumor-specific CD8+ T cells mediating tumor rejection. Clinical assessment of both ligand-blocking (BI-1808) and agonist (BI-1910) -TNFR2 antibodies is currently ongoing. Graphical abstractO_LILigand-blocking anti-TNFR2 mAbs (BI-1808 and 3F10) deplete CCR8+ T regs and activate myeloid cells, remodeling the TME and leading to CD8+ T cell killing of cancer cells. T reg depletion and myeloid activation are mediated through interaction with activating Fc{gamma}Rs and the inhibitory Fc{gamma}RIIB, respectively. C_LIO_LIAgonist anti-TNFR2 mAbs (BI-1910 and 5A05) intrinsically agonize TNFR2 on T cells and NK cells, which is enhanced by Fc{gamma}RIIB crosslinking. The resulting broad lymphocyte activation mediates cancer cell killing. C_LI O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=127 SRC="FIGDIR/small/697572v1_ufig1.gif" ALT="Figure 1"> View larger version (30K): org.highwire.dtl.DTLVardef@3ecc17org.highwire.dtl.DTLVardef@c936a7org.highwire.dtl.DTLVardef@23189aorg.highwire.dtl.DTLVardef@243a05_HPS_FORMAT_FIGEXP M_FIG C_FIG

immunology↗

Synthetic STING agonists elicit powerful vaccine adjuvancy providing robust central memory and anti-tumour effects

Drugs that target the innate immune sensor STING are known to be effective in modulating the immune infiltrate of the tumour microenvironment. STING agonists have potential to enhance responses to checkpoint inhibitor therapy, however, their ability to influence and shape adaptive immune responses is poorly understood. Here, we investigated the impact of a range of synthetic STING agonists on antigen specific CD8+ T-cell responses to soluble antigen using the murine OT-1 adoptive transfer model with Ovalbumin as the antigen to monitor T cell responses. Our data demonstrate that synthetic STING agonists are able to stimulate antigen specific T-cell expansion in response to challenge in mice. This effect required expression of STING, an intact myeloid compartment and Type-I IFN and TNF signalling. Expanded T-cells post treatment differed from those induced by the established immune adjuvant, anti-CD40 antibody through lower induction of the immune checkpoint receptor PD-1. Furthermore, our data revealed a marked increase in the induction and persistence of CD8+ central memory cells after STING agonist and antigen challenge. Finally, we demonstrate that following rechallenge, STING agonism produced larger secondary responses that could be translated into enhanced tumour protection and survival. Therefore, synthetic STING agonists are capable of acting as potent immune adjuvants and can induce robust memory formation leading to better recall and tumour control. Critically, these benefits along with the lower expression of PD-1, have implications for their use as adjuvants for multiple immunotherapy and vaccine applications.

immunology↗