Peroxisomes Are Critical for the Development and Maintenance of B1 and Marginal Zone B Cells but Dispensable for Follicular B Cells and T Cells.

Antioxidant systems maintain cellular redox (oxidation-reduction) homeostasis. In contrast with other key redox pathways, such as the thioredoxin system, glutathione, and NF-E2-related factor 2 (Nrf2), little is known about the function of the redox-sensitive organelle "peroxisome" in immune cells. In this study, we show that the absence of peroxisomes in conditional -deficient mice strikingly results in impaired homeostatic maintenance of innate-like B cells, namely, B1 and marginal zone B cells, which translates into a defective Ab response to Surprisingly, however, follicular B2 cell development, homeostatic maintenance, germinal center reactions, Ab production, class switching, and B cell memory formation were unaffected in -deficient animals. Similarly, T cell development and responses to viral infections also remained unaltered in the absence of Thus, this study highlights the differential requirement of peroxisomes in distinct lymphocyte subtypes and may provide a rationale for specifically targeting peroxisomal metabolism in innate-like B cells in certain forms of B cell malignancies involving B1 cells.