369 Single-cell RNA sequencing analysis of a COVID-19-associated maculopapular rash in a psoriasis patient treated with ustekinumab

The 2019 coronavirus disease (COVID-19) primarily affects the respiratory system, but extra pulmonary manifestations, including the skin, have been well documented. However, transcriptomic profiles of skin lesions have not been performed so far. Here, we present a single-cell RNA sequencing analysis in a patient with COVID-19 infection suffering from a maculopapular skin rash while on treatment with ustekinumab for his underlying psoriasis. Results were compared to 4 healthy control individuals. Lesional tissue showed a primarily type-1 interferon triggered pattern with highest levels of genomic dysregulation in keratinocytes, but no evidence of type-2, type-17 or type-22 T-cell immune activation. Viral entry receptors ACE2 and TMPRSS2 were sparsely expressed in keratinocytes of the patient, while ACE2 expression was not detected in healthy control individuals. Among immune cells, cytotoxic lymphocytes showed upregulation of IFNG and killer molecules GZMA, GZMB, GZMH and GNLY, and regulatory T cells expressed ICOS, CD27, and CXCL13. Conversely, we found significant downregulation of several anti-inflammatory mediators in stromal cells including fibroblasts, including the dual specificity protein phosphatase 2 DUSP2. This first transcriptomic description of a COVID-19 associated rash might help to gain a better understanding of SARS-CoV2 associated skin conditions.