Inhibition of LTβR-signalling blocks epithelial apoptosis and activates endogenous Wnt-induced regeneration

Lymphotoxin β-receptor-signalling orchestrates lymphoid neogenesis and subsequent tertiary lymphoid structures (TLS) associated with severe chronic inflammatory diseases spanning multiple organ systems. How LTβR-signalling drives chronic tissue damage particularly in the lung, which mechanism(s) regulate this process, and whether LTβR-blockade might be of therapeutic value has remained unclear. Here we demonstrate increased lymphotoxin expression of LTbR-ligands on myeloid and adaptive and innate immune-cells, enhanced non-canonical NF-κB signalling and enrichment of LTβR-target gene expression in epithelial cells of lungs from patients and mice with smoking-associated chronic obstructive pulmonary disease (COPD). Accordingly, Therapeutic inhibition of LTβR-signalling in young and aged mice with COPD disrupted TLS, reverted lung tissue destruction, airway-fibrosis and systemic muscle wasting. Mechanistically, we identified that LTβR-signalling blockade leads to diminished cell-death, concomitantly reactivated endogenous Wnt/β-catenin-signalling in alveolar epithelial cells and reduced TGFβ-signalling in airways. These findings highlight LTβR as a viable therapeutic target against TLS induced tissue damage that translates into novel anti-inflammatory, regenerative strategies to treat COPD. Expression data of mice exposed to either filtered air or cigarette smoke or cigarette smoke plus LTβR-Ig fusion protein