Single-cell RNA-sequencing of skin, fresh blood, and cultured peripheral blood mononuclear cells from a patient with drug-induced hypersensitivity syndrome and healthy volunteers

Purpose: Determine new therapeutic targets for a refractory drug-induced hypersensitivity syndrome/DRESS using single cell transcriptomic analysis. Methods: Skin cells were dissociated from skin biopsies of a patient with DRESS and 5 healthy volunteers using enzymatic digestion, then viable skin cells were sorted using flow cytometry. Peripheral blood mononuclear cells (PBMCs) were isolated from peripheral blood using Ficoll-paque density separation. PBMCs were cultured with or without medications for 4 days. In detail, 200,000 PBMCs were cultivated in 200ul of RPMI-1640 supplemented with 10% human AB serum with (PBMC_T4_BACT) or without (PBMC_T4_CTRL) 48 ug/mL sulfamethoxazole/trimethoprim (SMX-TMP). For the in vitro therapeutic experiments, PBMCs were cultured in the presence of SMX-TMP with (DRESS_Day4_TOFA) or without (DRESS_Day4_BACT) tofacitinib. The patient was treated with 10mg/d of tofacitinib, a JAK3 inhibitor. The freshly isolated PBMCs were collected again two weeks after initiation of intervention (PBMC_POST2W). Single cells from the skin, freshly isolated PBMCs, and culture PBMCs were captured using droplet based single-cell approach (10x Genomics) and library were prepared. Results: The lymphocytes in skin and PBMCs exhibited upregulation of skin-homing chemokine receptors, CCR4 and CCR10, and JAK3 and STAT1. Treatment with tofacitinib dramatically extinguished skin inflammation in a chronic refractory case of DiHS/DRESS. Conclusions: A successful intervention with tofacitinib in a refractory case of DiHS/DRESS was guided by the use of scRNAseq, which demonstrated aberrant activity in the JAK-STAT pathway.

Transcriptome profiles of skin, blood, and cultured PBMCs were generated by droplet-based single cell RNA-seq.