New PASTA Method Enhances Spatial Biology for Multimodal Tissue Analysis
A new method called protein and nucleic acid serial tyramide amplification (PASTA) has been developed to address technical challenges in spatial biology. Reported by Michel, McCallum, Wu, and colleagues in Nature Methods, PASTA combines highly sensitive protein detection with RNA visualization within the same tissue section. This approach aims to overcome limitations of conventional fluorescence-based detection, such as weak signals, overlapping emission spectra, and the restricted number of markers that can be measured simultaneously, especially in formalin-fixed, paraffin-embedded (FFPE) tissue samples. PASTA utilizes tyramide amplification, where horseradish peroxidase (HRP) activity leads to the localized deposition of oligonucleotides, which are short synthetic DNA sequences. These oligonucleotide tags can be detected in repeated imaging cycles, allowing for the sequential identification of numerous targets and expanding the measurable features while preserving spatial relationships among cells. The m... 
