Salvador de la Torre Gonzalez

Google Summer of Code 2025 & 2026 Contributor

email: delatorregonzalezsalvador[at]gmail[dot]com

Education: Mathematics and Computer Engineering, University of Seville, Spain

Completed project: CARTopiaX: an Agent-Based Simulation of CAR T-Cell Therapy built on BioDynaMo
CAR T-cell therapy is a form of cancer immunotherapy that engineers a patient’s T cells to recognize and eliminate malignant cells. Although highly effective in leukemias and other hematological cancers, this therapy faces significant challenges in solid tumors due to the complex and heterogeneous tumor microenvironment. CARTopiaX is an advanced agent-based model developed to address this challenge, using the mathematical framework proposed in the Nature paper “In silico study of heterogeneous tumour-derived organoid response to CAR T-cell therapy,” successfully replicating its core results. Built on BioDynaMo, a high-performance, open-source platform for large-scale and modular biological modeling, CARTopiaX enables detailed exploration of complex biological interactions, hypothesis testing, and data-driven discovery within solid tumor microenvironments. The project achieved major milestones, including simulations that run more than twice as fast as previous model, allowing rapid scenario exploration and robust hypothesis validation; high-quality, well-structured, and maintainable C++ code developed following modern software engineering principles; and a scalable, modular, and extensible architecture that fosters collaboration, customization, and the continuous evolution of an open-source ecosystem. Altogether, this work represents a meaningful advancement in computational biology, providing researchers with a powerful tool to investigate CAR T-cell dynamics in solid tumor and accelerating scientific discovery while reducing the time and cost associated with experimental wet-lab research.

Project Proposal: URL

Mentors: Vassil Vassilev, Lukas Breitwieser, Luciana Melina Luque, Tobias Duswald

Completed project: CARTopiaX: Extending a Next-Generation Platform for Computational Cancer Biology
This project extended CARTopiaX, an agent-based model built on BioDynaMo, to reproduce a published in vitro study of CAR T-cell therapy in a hypoxic 3D tumor model (Ando et al., 2019). The model was extended with a new cylindrical tumor geometry, controllable oxygen gradients, glucose as a new diffusing nutrient, and new cell behaviors, including metabolic competition between CAR T-cells and cancer cells. A Bayesian optimization tool (Optuna, TPE) was also added to calibrate model parameters against experimental data while minimizing the number of expensive simulations. The extended model reproduces the key trends of the study, including emergent behaviors, and offers an in silico explanation of the observed “non-contact mediated” CAR T-cell cytotoxicity using quantities that are hard to measure in the lab, such as death causes per radius. This demonstrates CARTopiaX as a flexible platform for fast, low-cost in silico hypothesis testing in CAR T-cell research.

Project Proposal: URL

Mentors: Vassil Vassilev, Lukas Breitwieser, Luciana Melina Luque

Presentations

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