ABCB1 and systemic lupus erythematosus: PBMC cultures also play a key role in the search for potential biomarkers of SLE, such as non-coding circular RNA hsa_circ_0000479 [92], ATP-binding cassette subfamily B member 1 (ABCB1), Interferon Alpha Inducible Protein 27 (IFI27) and phospholipid scramblase 1 (PLSCR1) [93].