Spatial characterization of interface dermatitis in cutaneous lupus reveals novel chemokine ligand-receptor pairs that drive disease.

Chemokines play critical roles in the recruitment and activation of immune cells in both homeostatic and pathologic conditions. Here, we examined chemokine ligand-receptor pairs to better understand the immunopathogenesis of cutaneous lupus erythematosus (CLE), a complex autoimmune connective tissue disorder. We used suction blister biopsies to measure cellular infiltrates with spectral flow cytometry in the interface dermatitis reaction, as well as 184 protein analytes in interstitial skin fluid using Olink targeted proteomics. Flow and Olink data concordantly demonstrated significant increases in T cells and antigen presenting cells (APCs). We also performed spatial transcriptomics and spatial proteomics of punch biopsies using digital spatial profiling (DSP) technology on CLE skin and healthy margin controls to examine discreet locations within the tissue. Spatial and Olink data confirmed elevation of interferon (IFN) and IFN-inducible CXCR3 chemokine ligands. Comparing involved versus uninvolved keratinocytes in CLE samples revealed upregulation of essential inflammatory response genes in areas near interface dermatitis, including AIM2 . Our Olink data confirmed upregulation of Caspase 8, IL-18 which is the final product of AIM2 activation, and induced chemokines including CCL8 and CXCL6 in CLE lesional samples. Chemotaxis assays using PBMCs from healthy and CLE donors revealed that T cells are equally poised to respond to CXCR3 ligands, whereas CD14+CD16+ APC populations are more sensitive to CXCL6 via CXCR1 and CD14+ are more sensitive to CCL8 via CCR2. Taken together, our data map a pathway from keratinocyte injury to lymphocyte recruitment in CLE via AIM2-Casp8-IL-18-CXCL6/CXCR1 and CCL8/CCR2, and IFNG/IFNL1-CXCL9/CXCL11-CXCR3.
Competing Interests: Competing interests: JMR is an inventor on patent application #63/478,900 “Diagnosis of skin diseases in veterinary and human patients” for CTCL. JEH & JMR are inventors on patent application #62489191, “Diagnosis and Treatment of Vitiligo” which covers targeting IL-15 and Trm for the treatment of vitiligo; and on patent application #15/851,651, “Anti-human CXCR3 antibodies for the Treatment of Vitiligo” which covers targeting CXCR3 for the treatment of vitiligo. JEH holds equity in Rheos Medicines and TeVido BioDevices; is a founder with equity of Villaris Therapeutics, Aldena Therapeutics, NIRA Biosciences, Vimela Therapeutics, and Klirna Therapeutics; has served as a consultant for Pfizer, Sanofi Genzyme, Incyte, Sun Pharmaceuticals, LEO Pharma, Dermavant, Temprian Therapeutics, AbbVie, Janssen, Almirall, Methuselah Health, Pandion, AnaptysBio, Avita, Aclaris Therapeutics, The Expert Institute, BiologicsMD, Boston Pharma, Sonoma Biotherapeutics, Two Biotech, Admirx, Frazier Management, 3rd Rock Ventrures, Gogen Therapeutics, Granular Therapeutics, Platelet Biogenesis, BridgeBio, Merck, Matchpoint Therapeutics, and Klirna; has served as an investigator for Pfizer, Sanofi Genzyme, Incyte, Sun Pharmaceuticals, LEO Pharma, Dermavant, Aclaris Therapeutics, GSK, Celgene, Dermira, and EMD Serono. LZ, ML & YL are employees of NanoString Technologies. MR is principal or co-investigator of studies sponsored by Pfizer, Biogen, AbbVie, Incyte, LEO Pharma, Abeona Therapeutics, Dermavant, and Target RWE; and MR provides consulting for Pfizer, Biogen, Incyte, Takeda, Inzen, ROME Therapeutics, Almirall, Medicxi, Related Sciences, and VisualDx. Remaining authors declare that they have no competing interests.