Spatially-resolved transcriptomics reveal macrophage heterogeneity and prognostic significance in diffuse large B-cell lymphoma

Macrophages are abundant immune cells in the microenvironment of diffuse large B-cell lymphoma (DLBCL). Macrophage phenotyping by immunohistochemistry has varying prognostic significance across studies in DLBCL and does not provide a comprehensive analysis of macrophage subtypes. We hypothesized that whole-transcriptomic analysis (WTA) of macrophage in-situ would identify new macrophage subsets of biological and clinical significances. Overall design: Using digital spatial profiling with whole transcriptome analysis of CD68+ cells, we characterized macrophages in distinct spatial niches of reactive lymphoid tissues (RLTs) and DLBCL. We reveal previously unrecognized transcriptomic differences between macrophages populating in RLTs (light zone (LZ)/ dark zone (DZ), germinal center (GC)/ interfollicular (IF) regions), and in between disease states (RLTs and DLBCL). And we also captured the CD20+ cells in the same way, which was used for validation.