Induced microfold cells are required for the function of pulmonary tertiary lymphoid organs that promote mucosal immunity

Influenza-induced lung tertiary lymphoid organs depend on inducible microfold (iM) cells, with iM cell ablation reducing germinal center B cells and secretory IgA/IgG while impairing viral control.

• Why it matters: TLOs form during infection and inflammation, but how their mucosal immune function is organized—especially the role of iM cells in iBALT—was unclear.
• What they did: Using influenza-induced lung TLOs, the study shows iM cells are required for iBALT follicle architecture and measures immune cell populations and secretory IgA/IgG after iM cell ablation.
• The result: iM cells arise from epithelial progenitors responding to a RANKL signal from infiltrating T cells, linking patchy pneumonia inflammation to variable iM cell–iBALT coupling and suggesting targets for mucosal vaccination.

AI summary of the abstract · may contain errors · not medical advice · read the paper.