Cathepsin C inhibition reduces neutrophil serine protease activity and improves activated neutrophil-mediated disorders.

Cathepsin C (CatC) is an enzyme which regulates the maturation of neutrophil serine proteases (NSPs) essential for neutrophil activation. Activated neutrophils are key players in the innate immune system, and are also implicated in the etiology of various inflammatory diseases. This study aims to demonstrate a therapeutic potential for CatC inhibitors against disorders in which activated neutrophil-derived neutrophil extracellular traps (NETs) play a significant role.

Methylprednisolone pulse-enhanced neutrophil extracellular trap formation in mice with imiquimod-induced lupus-like disease, resulting in ischaemia of the femoral head cartilage.

Objectives: Methylprednisolone (mPSL) pulse therapy is an essential option for patients with active systemic lupus erythematosus, but there is a risk of adverse events related to microcirculation disorders, including idiopathic osteonecrosis of the femoral head (ONFH). Recent studies have revealed that excessive neutrophil extracellular traps (NETs) are involved in microcirculation disorders. This study aimed to demonstrate that mPSL pulse could induce NETs in lupus mice and identify the factors contributing to this induction.

Anti-PLAR Antibody Development During NELL1-Associated Membranous Glomerulonephritis Treatment: A Case Report.

A Japanese man in his early 70s was referred to our hospital because of massive proteinuria. Analysis of his kidney biopsy demonstrated glomerular subepithelial immune deposits containing immunoglobulin (Ig)G, which was dominant for the IgG1 subclass. Immunoperoxidase staining for neural epidermal growth factor-like 1 protein (NELL1) was positive on the glomerular capillary walls, whereas neither serum anti-phospholipase A2 receptor (PLAR) antibodies nor immunofluorescence staining for PLAR was positive.