design: total RNA was extracted from GFP+ Treg cells using the RNeasy Plus Mini Kit (Qiagen, 74134). RNA-Seq libraries construction and sequencing were performed on Haplox (Nanchang, China). Raw reads were trimmed using fastp (version 0.23.2) and aligned against mm10 genome reference with HISAT2 (version 2.1.0). The sam files were sorted and converted into BAM file format using Samtools (1.10). Sequencing and PCR duplicates were removed by picard MarkDuplicates (version 2.25.0). Deduplicated mapped BAM reads were quantified by HTSeq count (0.11.3). Count files were then fed into DESeqDataSetFromHTSeqCount function in DESeq2 package (1.34.0) to perform differential expression analysis. The significance threshold was set to P-value < .05 and |log2FC| > 0.5.