A DIY guide for image-based spatial transcriptomic: TLS as a case example

Spatial RNA profiling methods provide insight to the cellular heterogeneity and spatial architecture of complex, multi-cellular systems. Combining molecular and spatial information provides important clues to study tissue architecture in development and disease. Here, we present a comprehensive do-it-yourself guide to perform such experiments at reduced costs leveraging open-source approaches. This guide spans the entire life cycle of a project, from its initial definition to experimental choices, wet lab approaches, instrumentation and analysis. As a concrete example, we focus on Tertiary lymphoid structures (TLS), which we use to develop typical questions that can be addressed by these approaches.