Dupilumab-associated head and neck dermatitis shows a pronounced type 22 immune signature mediated by oligoclonally expanded T cells.

Dupilumab, an IL4R-blocking antibody, has shown clinical efficacy for atopic dermatitis (AD) treatment. In addition to conjunctivitis/blepharitis, the de novo appearance of head/neck dermatitis is now recognized as a distinct side effect, occurring in up to 10% of patients. Histopathological features distinct from AD suggest a drug effect, but exact underlying mechanisms remain unknown. We profiled punch biopsies from dupilumab-associated head and neck dermatitis (DAHND) by using single-cell RNA sequencing and compared data with untreated AD and healthy control skin. We show that dupilumab treatment was accompanied by normalization of IL-4/IL-13 downstream activity markers such as CCL13, CCL17, CCL18 and CCL26. By contrast, we found strong increases in type 22-associated markers (IL22, AHR) especially in oligoclonally expanded T cells, accompanied by enhanced keratinocyte activation and IL-22 receptor upregulation. Taken together, we demonstrate that dupilumab effectively dampens conventional type 2 inflammation in DAHND lesions, with concomitant hyperactivation of IL22-associated responses.

HTLV-1 Presenting as an Incidental Finding after a Cosmetic Procedure.

A 44-year-old woman presented to a plastic surgeon for liposuction of the abdomen, back, and flanks, a gluteal fat transfer, and a vertical pattern breast lift and small reduction. The patient had a medical history of significantly well-controlled hypertension for 4 years treated with hydrochlorothiazide and amlodipine. She had been pregnant four times and delivered six children with two sets of twins. She was allergic to latex and denied a history of smoking. Her physical examination was unremarkable and her body mass index (BMI) was 26.1. No skin lesions were evident (Figure 1). Her preoperative laboratory findings were within normal limits, with unremarkable electrocardiogram (EKG), chest x-ray, and mammogram. The patient underwent a successful surgical procedure, and the excised breast tissue and skin were sent to pathology for routine evaluation. Surgery removed 220 g of breast tissue from the left breast and 45 g was excised from the right one. The histopathology depicted atypical T-cells in the epidermis and superficial dermis of both left and right breasts. Physical examination failed to evidence lymph-adenopathy or masses. The patient denied weight loss, night sweats, or fever; however, due to her Caribbean heritage, adult T-cell leukemia/ lymphoma was considered and submitted for further histologic workup.

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

Coronavirus disease 2019 (COVID-19) primarily affects the respiratory system but extrapulmonary manifestations, including the skin, have been well documented. However, transcriptomic profiles of skin lesions have not been performed thus far. Here, we present a single-cell RNA sequencing analysis in a patient with COVID-19 infection with a maculopapular skin rash while on treatment with the interleukin (IL)-12/IL-23 blocker ustekinumab for his underlying psoriasis. Results were compared with healthy controls and untreated psoriasis lesions. We found the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral entry receptors ACE2 and TMPRSS2 in keratinocytes of the patient with COVID-19, while ACE2 expression was low to undetectable in psoriasis lesions and healthy skin. Among all cell types, ACE2+ keratinocyte clusters showed the highest levels of transcriptomic dysregulation in COVID-19, expressing type 1-associated immune markers such as CXCL9 and CXCL10. In line with a generally type 1-skewed immune microenvironment, cytotoxic lymphocytes showed increased expression of the IFNG gene and other T-cell effector genes, while type 2, type 17, or type 22 T-cell activation was largely absent. Conversely, downregulation of several anti-inflammatory mediators was observed. This first transcriptomic description of a COVID-19-associated rash identifies ACE2+ keratinocytes displaying profound transcriptional changes, and inflammatory immune cells that might help to improve the understanding of SARS-CoV-2-associated skin conditions.