CD19 and neoplasm: We found that PPARδ is significantly upregulated in tumor-induced IL-10+ Bregs with a phenotype of CD19+CD24hiIgDlo/−CD38lo or CD19+CD24hiIgDlo/−CD38hi in both mice and humans, and the level of PPARδ expression was correlated with their potential to produce IL-10 and to inhibit T cell activation.