Investigation on the vaccination potential of IL4i1 deficient dendritic cells in Chronic lymphocytic leukemia

Project Information

engineereD to Clear

Grant agreement ID: 101066882

DOI

10.3030/101066882

Project closed

EC signature date 28 July 2022

Start date 1 October 2022

End date 30 September 2024

Funded under

• Marie Skłodowska-Curie Actions (MSCA)

Total cost

No data

EU contribution

€ 189 687,36

Coordinated by

DEUTSCHES KREBSFORSCHUNGSZENTRUM HEIDELBERG
Germany

Periodic Reporting for period 1 - engineereD to Clear (Investigation on the vaccination potential of IL4i1 deficient dendritic cells in Chronic lymphocytic leukemia)

Reporting period: 2022-10-01 to 2024-09-30

Summary of the context and overall objectives of the project

The primary objective of this project is to enhance the efficacy of dendritic cell (DC)-based immunotherapy by targeting the Il4i1 metabolic immune checkpoint. Chronic Lymphocytic Leukemia (CLL) presents unique immunosuppressive challenges, making it imperative to identify and harness mechanisms that can reinvigorate immune responses. The project explores whether Il4i1-knockout (KO) dendritic cells, which demonstrate superior antigen presentation, T-cell activation, and migration capacities, can serve as an advanced therapeutic tool.

Our approach involves differentiating Il4i1-WT and Il4i1-KO conventional dendritic cells (cDC1s) from mouse bone marrow to evaluate their functional improvements. Key assays include antigen presentation and migration studies, OT-1 T-cell proliferation, and in vivo tracking of DC migration. Additionally, integrating mass spectrometry-based immunopeptidomics aims to identify hTCL1A peptides for DC feeding, offering potential avenues for a vaccine strategy within the TCL1-AT mouse model of CLL.

The project's impacts are twofold: First, it addresses the unmet need for more effective DC-based therapies, particularly in the context of CLL's complex immune evasion tactics. Second, by leveraging the increased immunogenicity of Il4i1-KO DCs, the findings could inform broader applications in immunotherapy for various cancers. Given the strategic importance of advancing cancer immunotherapy, these results are poised to contribute significantly to the field, with potential translational outcomes impacting clinical practices.

This project's significance lies in its innovative focus on Il4i1 as a metabolic immune checkpoint and the scale of its expected impact, which includes improving survival rates, reducing relapse, and setting a precedent for next-generation immunotherapies.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

Technical and Scientific Activities and Achievements

Activities Performed
1. Generation of Il4i1-KO Dendritic Cells
- Bone marrow cells from Il4i1-WT and Il4i1-KO mice were differentiated into conventional dendritic cells (cDC1s) using standard protocols.
- Differentiation was assessed by flow cytometry, gating on B220-negative populations.

2. Functional Characterization of cDC1s
- Antigen Presentation Assay: Primary murine cDC1s (WT and KO) were tested for their ability to present antigens using SIINFEKL peptide and OT-1 T-cell proliferation assays.
- Migration Studies: Transwell migration assays and in vivo DC migration studies (via s.c. injection) demonstrated enhanced CCR7 expression and superior migration capacity in Il4i1-KO DCs.

3. Molecular Analyses
- Surface marker expression was quantified using flow cytometry, while mRNA and protein levels of relevant markers were assessed via qPCR and Western blotting, respectively.
- Bulk RNA sequencing was conducted on WT and KO cDC1s to elucidate gene expression changes linked to enhanced functionality.

4. Immunopeptidomics and Mass Spectrometry
- Mass spectrometry-based immunopeptidomics is under progress to identify potential MHC-I binding peptides, including hTCL1A peptides, for use in DC vaccination strategies tailored for CLL.

5. Functional Immune Assays
- Effector cytotoxic T lymphocyte (CTL) responses against identified hTCL1A peptides were tested in the Eu-TCL1 mouse model.
- Preliminary B-cell killing assays demonstrated the potential of peptide-loaded DCs to enhance anti-tumor immunity.

Main Achievements
1. Enhanced Functional Profile of Il4i1-KO DCs
- Il4i1-KO cDC1s showed higher antigen presentation capacity, robust T-cell activation, and improved migration compared to WT controls.
- These results confirm Il4i1 as a critical metabolic checkpoint and a target for enhancing DC-based immunotherapy.

2. Identification of Therapeutic Peptides
- Potential MHC-I binding peptides were successfully identified, paving the way for their use in vaccination strategies targeting TCL1-expressing CLL.

These scientific achievements represent a significant step toward developing advanced DC-based therapies that leverage the enhanced immunogenicity of Il4i1-KO DCs, with promising implications for future clinical applications.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

Results and Potential Impacts:

IL4I1 knockout (KO) dendritic cells (DCs) showed enhanced antigen presentation, T-cell activation, and migration compared to wild-type (WT) DCs.
Specific human TCL1A peptides were identified for potential use in DC-based vaccination strategies against chronic lymphocytic leukemia (CLL).
IL4I1 was found to be expressed by activated DCs, suggesting a role in immune regulation.
IL4I1-KO DCs exhibited increased expression of CCR7, a chemokine receptor involved in DC migration, indicating their potential for improved trafficking to lymph nodes where they can initiate immune responses.
The project developed several assays and protocols for studying DC function and migration, including an in vivo DC migration assay.

Key Needs for Further Uptake and Success:

Further research is needed to fully understand the mechanisms by which IL4I1 regulates DC function and T cell activation.
Additional preclinical studies are needed to evaluate the efficacy and safety of IL4I1-targeted therapies in vivo.
Demonstration of the clinical potential of IL4I1-based therapies through clinical trials.
Exploration of potential intellectual property protection and commercialization strategies.
Collaboration with industry partners to translate research findings into clinical applications.
Supportive regulatory and standardization frameworks to facilitate the development and approval of IL4I1-based therapies.

The project's findings contribute to our understanding of immune regulation and have the potential to lead to the development of novel DC-based vaccines for cancers and other diseases.