Leishmania is an intracellular protozoan parasite that establishes infection within host macrophages by subverting their immune defenses and reprogramming cellular metabolism. Previous studies at the bulk population level, including transcriptomic analyses, have revealed significant alterations in macrophage gene expression upon infection. These include suppression of pro-inflammatory pathways and modulation of macrophage polarization states, facilitating parasite survival and replication.
However, macrophages are inherently heterogeneous, and bulk approaches — even when applied to relatively homogenous bone marrow-derived macrophages — mask cell-to-cell variability that may be critical for understanding host-pathogen dynamics. To address this, we aim to perform single-cell RNA sequencing (scRNA-seq) using the 10x Genomics platform on uninfected and Leishmania-infected macrophages. This approach will enable high-resolution dissection of macrophage heterogeneity, with a focus on characterizing distinct transcriptional profiles and polarization states (e.g., M1-like vs. M2-like phenotypes) in response to the intracellular amastigote stage of Leishmania.
By profiling thousands of individual cells per condition, we seek to uncover specific macrophage subpopulations, transcriptional trajectories, and infection-induced states that contribute to Leishmania persistence or clearance, offering new insights into host-pathogen interactions and immune evasion strategies at the single-cell level.