Researchers reported that paclitaxel chemotherapy expands a population of TREM2+ macrophages in the tumor microenvironment, a change linked to impaired antitumor immunity and reduced therapeutic efficacy. The team contrasted paclitaxel with nab‑paclitaxel and traced an immunological mechanism that may explain differences in clinical performance between formulations. The study — published in Nature Communications — maps how standard chemotherapies can reshape myeloid populations and suggests macrophage modulation could be necessary to sustain chemotherapy benefits. The findings flag an immunological liability for paclitaxel and identify TREM2+ macrophages as a potential biomarker or target for combination strategies.