[edit]
GeST: Towards Building A Generative Pretrained Transformer for Learning Cellular Spatial Context
Proceedings of the 20th Machine Learning in Computational Biology meeting, PMLR 311:1-11, 2025.
Abstract
Learning spatial context of cells through pretraining on spatial transcriptomics (ST) data may empower us to decipher tissue organization and cellular interactions. Yet, transformer-based generative models often focus on modeling individual cells, overlooking the intricate spatial relationships within them. To address this limitation, we develop GeST, a deep transformer model pretrained by a novel spatially informed generation task: Predicting cellular expression profile of a given location based on the information from its neighboring cells. GeST integrates a specialized spatial attention mechanism for efficient pretraining, a flexible serialization strategy for sequentializing ST data, and a cell tokenization method for quantizing gene expression profiles. We pretrained GeST on large-scale ST datasets across multiple ST technologies, achieving superior performance in generating previously unseen spatial cell profiles, extracting spatial niche embeddings in a zero-shot manner, and annotating spatial regions. Furthermore, GeST can simulate gene expression changes in response to perturbations of cells within spatial context, closely matching existing experimental results. GeST offers a powerful generative pre-training framework for learning spatial contexts.