Tumour-necrosis factors

How the airway microbiome protects against bacterial pneumonia remains unclear. Here, the authors identify airway bacterial species that activate the immune system to facilitate rapid clearance of the pathogen Streptococcus pneumoniae from the lung.

The study suggests a link between ICOS-ICOSL signaling and LTa3 induction on T cells. LTa3 subsequently activates fibroblasts in the salivary gland, leading to formation of tertiary lymphoid tissues (TLS).

Reduction of systemic autoimmunity using TNF blockers may also reduce inflammatory diseases in other organs. Here, the authors use a patient database and scRNA-seq to link autoimmune diseases to benign prostatic hyperplasia (BPH), and demonstrate that prostatic hyperplasia is reduced by TNF blockers in humans and mice.

Expansion of synovial fibroblast is associated with rheumatoid arthritis (RA) progression, but how this expansion is regulated is still not clear. Here the authors use a mouse RA model, single cell RNA sequencing and in vitro analyses to show that inducing ferroptosis and suppressing TNF signaling reduce fibroblast numbers and ameliorate experimental arthritis.