M2 macrophages promote IL-10+B-cell production and alleviate asthma in mice.

Introduction: B cells have a central regulatory role in various diseases. While macrophages are found in the disease microenvironment and interact with tissue and diverse immune cells, their relationship with B cells remains poorly explored.

Methods: This study used an asthma animal model and macrophage depletion and demonstrated a significant exacerbation of asthma symptoms upon macrophage removal, coupled with a marked reduction in IL-10⁺ B-cell expression.

Results: Further analysis revealed that the macrophages interacting with IL-10⁺ B cells in the asthma microenvironment were of the M2 subtype. Furthermore, our sequencing data indicated a potential mechanism wherein M2 macrophages promote IL-10⁺ B-cell activity through the TGF-β pathway and oxidative phosphorylation pathways.

Conclusion: These findings suggest that M2 macrophages modulate IL-10⁺ B cells, ultimately mitigating asthma symptoms in mouse models.