IRF4 and rheumatoid arthritis: In the gene expression profile of TL1A-stimulated RA-FLS, the expression of spectrin repeat-containing nuclear envelope 1, Fc receptor-like 2, PYD (pyrin domain)-containing 1, cell division cycle 45 homolog, signal transducer and activator of transcription 5B, and interferon regulatory factor 4 [15] were regulated by TL1A.