Constructing a cell atlas involves several key steps: 1. Tissue Sampling: Collection of diverse tissue samples from various organs. 2. Single-Cell Analysis: Techniques like single-cell RNA sequencing (scRNA-seq) are employed to analyze gene expression at the single-cell level. 3. Spatial Mapping: Advanced imaging techniques such as immunohistochemistry and in situ hybridization map the spatial location of cells. 4. Data Integration: Computational methods integrate diverse datasets to create a comprehensive atlas.