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Cobbold, M.

Publications and source records attributed to Cobbold, M..

5 recordsLinked to original sources

Mechanisms regulating combination effect of antibody-drug conjugates and cancer immunotherapy

Antibody-drug conjugates (ADCs) have emerged as a transformative class of cancer therapeutics with important challenges still to be addressed. Combination of ADC with immunotherapy is a promising strategy but mechanisms and effective application remain to be determined. We evaluated ADC combinations with T cell engagers (TCEs) and checkpoint inhibitors (CPI). ADC-TCE combinations produced robust antitumor activity independent of antigen and payload and persisted despite ADC-related T cell loss. Efficacy was dominated by a direct effect of ADC on tumor cells. ADCs induced autophagy that upregulated TNF receptors (TNFRs) and mannose-6-phosphate receptors (M6PR). When ADCs were combined with TCEs TNF released by T cells was primarily responsible for potent antitumor effect of combination. In contrast, M6PR was dispensable for ADC-TCE activity but critical for combinations with CPI expanded antigen-specific T cells via enhanced granzyme B uptake. These data reveal a unifying, target- and payload-agnostic mechanism enabling rational ADC-immunotherapy combinations. SignificanceThis is first evidence that ADC-induced tumor cell autophagy via up-regulation of TNFR and M6PR could be responsible for potent antitumor effect of combination of ADC with TCE. TCEs exploit a TNF-TNFR axis, whereas antigen-specific T cells leverage granzyme B-M6PR uptake. This mechanistic framework explains broad ADC-TCE synergy and guides rational selection of ADC-immunotherapy combinations beyond checkpoint blockade.

immunology↗

BCMA/CD19 dual-targeting with FasTCAR: AZD0120 demonstrates potent preclinical efficacy in multiple myeloma

Chimeric antigen receptor (CAR)-T cell therapy has improved outcomes for patients with multiple myeloma (MM), but its broader use is restricted by manufacturing complexities and treatment-related toxicities. AZD0120 is a dual-targeting B-cell maturation antigen (BCMA)/CD19 CAR-T cell therapy manufactured via the rapid FasTCAR process. We developed a dual-targeting "loop" CAR that incorporates a novel humanized anti-BCMA single-chain variable fragment (scFv), clone SG, and an FMC63-derived anti-CD19 scFv. This AZD0120 CAR preserved functional binding to both antigens and conferred robust in vitro and in vivo cytotoxicity while maintaining single-antigen reactivity. Conventional manufacture of CAR-T cells with the AZD0120 CAR (AZD0120C) yielded cells with minimal tonic signaling, limited responsiveness to soluble BCMA, and preservation of naive/stem cell memory-enriched phenotypes, yet robust cytokine production upon BCMA+ target engagement. AZD0120C demonstrated cytotoxicity comparable to benchmark BCMA CAR-Ts across MM lines in vitro and showed strong in vivo expansion and tumor control in xenograft models. FasTCAR manufacturing - designed to shorten vein-to-vein timelines and enrich less-differentiated phenotypes - further enhanced in vivo performance: AZD0120 consistently achieved superior tumor control and greater CAR-T expansion vs AZD0120C across disseminated MM.1S, NALM-6, and JeKo-1 models, with superior efficacy observed at lower cell doses. Collectively, these data support clinical evaluation of AZD0120 as a differentiated BCMA/CD19 CAR-T cell therapy with the potential to improve disease control and patient access in MM. Key PointsO_LIAZD0120 is a dual-targeting CAR-T that displays a favorable anti-myeloma functional profile and co-targets a source of potential relapse C_LIO_LIThe FasTCAR process yields TN/SCM-rich CAR-T populations, promotes in vivo expansion and achieves potent tumor control in xenograft models C_LI

cancer biology↗

Antibody peptide epitope conjugates for αPD-1 therapy-resistant head and neck squamous cell carcinoma

Poor tumor antigenicity is an important cause of non-response to immune checkpoint blockade (ICB)-therapy in many cancer patients and mandates new treatment strategies. Here we explore the use of proteolytically activated antibody-peptide epitope conjugates (APECs) to redirect the immunological effector activities of tumor-infiltrating antiviral bystander CTLs against head and neck squamous cell carcinoma (HNSCC) by loading cancer cell surface MHC I proteins with viral peptides. We find that inflationary T cell memory responses against common viral pathogens such as CMV and EBV unfold superior anti-tumor activity compared to conventional memory responses under APEC therapy in an ICB-resistant preclinical model of HNSCC. Mechanistically, APEC activation required cancer cell-intrinsic protease activity, even for proteases expressed by cells of the tumor stroma. Data mining and functional screening identified the protease activity of plasminogen activator urokinase (PLAU) as widely shared between human HNSCC cancers and as a highly efficient proteolytic activator of APECs. Furthermore, peripheral blood analysis in HNSCC patients reliably predicts the specificity, magnitude, and quality of intratumoral bystander CTL, thus allowing for the screening of HNSCC patients who may benefit most from APEC therapy.

immunology↗

The differential immunological impact of photon vs proton radiation therapy in high grade lymphopenia

Radiation therapy has long been a cornerstone of cancer treatment. More recently, immune checkpoint blockade has also been applied across a variety of cancers, often leading to remarkable response rates. However, photon-based radiotherapy - which accounts for the vast majority - is also known to frequently induce profound lymphopenia, which might limit the efficacy of immune system based combinations. Proton beam therapy is known to produce a less drastic lymphopenia, which raises the possibility of greater synergy with immunotherapy. In this study we aimed to explore the exact nature of the differential impact of the two radiation modalities upon the immune system. We used multiparametric flow cytometry and deep sequencing of rearranged TCRb loci to investigate a cohort of 20 patients with gastrointestinal tumors who received either therapy. Proton-treated patients remained relatively stable throughout treatment for most metrics considered, whereas those who received photons saw a profound depletion in naive T cells, increase in effector/memory populations, and loss of TCR diversity. The repertoires of photon-treated patients underwent oligoclonal expansion after their lymphocyte count nadirs, particularly of CD8+ Temra cells, driving this reduction in diversity. Across the entire cohort, this reduction in post-nadir diversity inversely correlated with the overall survival time of those patients who died. This raises the possibility that increased adoption of proton-based or other lymphocyte sparing radiotherapy regimes may lead to better survival in cancer patients.

immunology↗

Stitchr: stitching coding TCR nucleotide sequences from V/J/CDR3 information

The study and manipulation of T cell receptors (TCRs) is central to multiple fields across basic and translational immunology research. Produced by V(D)J recombination, TCRs are often only recorded in the literature and data repositories as a combination of their V and J gene symbols, plus their hypervariable CDR3 amino acid sequence. However, numerous applications require full-length coding nucleotide sequences. Here we present Stitchr, a software tool developed to specifically address this limitation. Given minimal V/J/CDR3 information, Stitchr produces complete coding sequences representing a fully spliced TCR cDNA. Due to its modular design, Stitchr can be used for TCR engineering using either published germline or novel/modified variable and constant region sequences. Sequences produced by Stitchr were validated by synthesizing and transducing TCR sequences into Jurkat cells, recapitulating the expected antigen specificity of the parental TCR. Using a companion script, Thimble, we demonstrate that Stitchr can process a million TCRs in under ten minutes using a standard desktop personal computer. By systemizing the production and modification of TCR sequences, we propose that Stitchr will increase the speed, repeatability, and reproducibility of TCR research. Stitchr is available on GitHub.

immunology↗