High Interferon Signature Leads to Increased STAT1/3/5 Phosphorylation in PBMCs From SLE Patients by Single Cell Mass Cytometry

• Published in: Frontiers in immunology Vol. 13; p. 833636
• Main Authors: Yiu, Gloria, Rasmussen, Tue Kruse, Tsai, Brandon L, Diep, Vivian K, Haddon, David J, Tsoi, Jennifer, Miller, Gopika D, Comin-Anduix, Begoña, Deleuran, Bent, Crooks, Gay M, Utz, Paul J
• Format: Journal Article
• Language: English
• Published: Switzerland Frontiers Media S.A 28.01.2022
• Subjects: Adult; autoantibodies; CyTOF mass cytometry; Female; Flow Cytometry; Humans; Immunology; interferon; Interferon Type I - analysis; Interferon Type I - physiology; Interleukins - analysis; Interleukins - physiology; Leukocytes, Mononuclear - metabolism; lupus (SLE); Lupus Erythematosus, Systemic - metabolism; Male; Middle Aged; Phosphorylation; Signal Transduction; Single-Cell Analysis; STAT1; STAT1 Transcription Factor - metabolism; STAT3 (signal transducer and activator of transcription 3); STAT3 (signal transducer and activator of transcription 3); lupus (SLE); STAT1; interferon signature; CyTOF mass cytometry; interferon; autoantibodies
• ISSN: 1664-3224; 1664-3224
• DOI: 10.3389/fimmu.2022.833636

The establishment of an "interferon (IFN) signature" to subset SLE patients on disease severity has led to therapeutics targeting IFNα. Here, we investigate IFN signaling in SLE using multiplexed protein arrays and single cell cytometry by time of flight (CyTOF). First, the IFN signature for SLE patients (n=81) from the Stanford Lupus Registry is determined using fluidigm qPCR measuring 44 previously determined IFN-inducible transcripts. IFN-high (IFN-H) patients have increased SLE criteria and renal/CNS/immunologic involvement, and increased autoantibody reactivity against spliceosome-associated antigens. CyTOF analysis is performed on non-stimulated and stimulated (IFNα, IFNγ, IL-21) PBMCs from SLE patients (n=25) and HCs (n=9) in a panel identifying changes in phosphorylation of intracellular signaling proteins (pTOF). Another panel is utilized to detect changes in intracellular cytokine (ICTOF) production in non-stimulated and stimulated (PMA/ionomycin) PBMCs from SLE patients (n=31) and HCs (n=17). Bioinformatic analysis by MetaCyto and OMIQ reveal phenotypic changes in immune cell subsets between IFN-H and IFN-low (IFN-L) patients. Most notably, IFN-H patients exhibit increased STAT1/3/5 phosphorylation downstream of cytokine stimulation and increased phosphorylation of non-canonical STAT proteins. These results suggest that IFN signaling in SLE modulates STAT phosphorylation, potentially uncovering possible targets for future therapeutic approaches.