Mapping the Immune Modulation Landscape Induced by Sanguisobae Radix at Single-Cell Resolution

Sanguisorbae radix (SR), a traditional Chinese medicine, is commonly used in China to enhance human immunity. Yet, its effects and underlying mechanisms on various types of immune cells remain to be fully explored. Here, we conduct single-cell transcriptomic analysis across human peripheral blood mononuclear cells (PBMCs) before and after taking SR. Our findings reveal that there were fluctuations in immune cell proportions in the bloodstream, including increased Mega/Platelets, Dendritic cells (DCs), CD8+ T cells, natural killer (NK) cells and Naïve CD4+ T cells, and decreased Mast cells, B cells, and Monocytes after taking SR. Among them, SR increased CD8+ T cells by stimulating the proliferation. Our results suggest that SR enhance viability of these types of immune cells by up-regulating genes related to ribosome protein and mitochondrial energetic metabolism. Notably, SR treatment significantly enhance the activity of Cytotoxic Effector T cells, a subtype of CD8+ T cells, by increasing the cytotoxicity score and the expression of toxic particle-related genes (such as LYZ and GZMK). Furthermore, our findings demonstrate significant inhibition of inflammation-associated genes and pathways by SR across various immune cell subsets, including T cells, Monocytes, and Mega/Platelets. Overall, our study highlights the transcriptional heterogeneity induced by SR treatment and its distinct modulation of various circulating immune cells, providing potential for the development of immunomodulatory therapeutics.