OBJECTIVE: To explore the clinical characteristics and genetic variant in a premature infant with Netherton syndrome (NS). METHODS: A neonate with NS caused by variants of SPINK5 gene diagnosed at the Children's Hospital Affiliated to Zhejiang University School of Medicine in March 2020 was selected as the study subject. Clinical data and family history were collected. Peripheral blood samples (2 mL each) were obtained from the child and her parents for whole-exome sequencing (WES). Candidate variants were subjected to pathogenicity classification and deleteriousness evaluation. This study has been approved by the Medical Ethics Committee of the Hospital (Ethics No. 2024-IRB-0251-P-01). RESULTS: The infant was born prematurely at 35⁺³ weeks due to "premature rupture of membranes for 4 hours" and exhibited generalized skin peeling, with meconium-stained amniotic fluid resembling bean curd residue. The condition improved with supportive treatments such as anti-infection and moisturizing therapy, though periodic hair loss had persisted. No similar case was reported by family history. WES has revealed a heterozygous c.1130delG (p.G377Efs*127) variant in exon 14 of the SPINK5 gene, which was inherited from her mother, and deletion of exons 1 ~ 33 of the SPINK5 gene, which was inherited from her father. CONCLUSION This case of NS presented with intrauterine onset in a preterm infant, which has not been previously reported. The identification of c.1130delG (p.G377Efs*127) variant has expanded the mutation spectrum of the SPINK5 gene.
Humans ; Serine Peptidase Inhibitor Kazal-Type 5/genetics* ; Netherton Syndrome/genetics* ; Female ; Infant, Newborn ; Infant, Premature ; Mutation ; Exome Sequencing ; Male

BACKGROUNDAtopic dermatitis (AD) is characterized by defective skin barrier and imbalance in T helper 1/T helper 2 (Th1/Th2) cytokine expression. Filaggrin (FLG) is the key protein to maintaining skin barrier function. Recent studies indicated that Th1/Th2 cytokines influence FLG expression in keratinocytes. However, the role of Th1/Th2 cytokines on FLG processing is not substantially documented. Our aim was to investigate the impact of Th1/Th2 cytokines on FLG processing.

METHODSHaCaT cells and normal human keratinocytes were cultured in low and high calcium media and stimulated by either interleukin (IL)-4, 13 or interferon-γ (IFN-γ). FLG, its major processing proteases and key protease inhibitor lymphoepithelial Kazal-type-related inhibitor (LEKTI) were measured by both real-time quantitative polymerase chain reaction and Western blotting. Their expression was also evaluated in acute and chronic AD lesions by immunohistochemistry.

RESULTSIL-4/13 significantly reduced, while IFN-γ significantly up-regulated FLG expression. IL-4/13 significantly increased, whereas IFN-γ significantly decreased the expression of kallikreins 5 and 7, matriptase and channel-activating serine protease 1. On the contrary, IL-4/13 significantly decreased, while IFN-γ increased the expression of LEKTI and caspase-14. Similar trends were observed in AD lesions.

CONCLUSIONSOur results suggested that Th1/Th2 cytokines differentially regulated the expression of major FLG processing enzymes. The imbalance between Th1 and Th2 polarized immune response seems to extend to FLG homeostasis, through the network of FLG processing enzymes.

Caspase 14 ; metabolism ; Cell Line, Tumor ; Cells, Cultured ; Dermatitis, Atopic ; metabolism ; Humans ; Immunohistochemistry ; Interferon-gamma ; metabolism ; Interleukin-13 ; metabolism ; Interleukin-4 ; metabolism ; Intermediate Filament Proteins ; metabolism ; Keratinocytes ; enzymology ; metabolism ; Proteinase Inhibitory Proteins, Secretory ; metabolism ; Serine Peptidase Inhibitor Kazal-Type 5 ; Th1 Cells ; metabolism ; Th2 Cells ; metabolism