| First Author | MacLean AJ | Year | 2024 |
| Journal | J Exp Med | Volume | 221 |
| Issue | 7 | PubMed ID | 38661717 |
| Mgi Jnum | J:352756 | Mgi Id | MGI:7625590 |
| Doi | 10.1084/jem.20232014 | Citation | MacLean AJ, et al. (2024) Regulation of pulmonary plasma cell responses during secondary infection with influenza virus. J Exp Med 221(7) |
| abstractText | During secondary infection with influenza virus, plasma cells (PCs) develop within the lung, providing a local source of antibodies. However, the site and mechanisms that regulate this process are poorly defined. Here, we show that while circulating memory B cells entered the lung during rechallenge and were activated within inducible bronchus-associated lymphoid tissues (iBALTs), resident memory B (BRM) cells responded earlier, and their activation occurred in a different niche: directly near infected alveoli. This process required NK cells but was largely independent of CD4 and CD8 T cells. Innate stimuli induced by virus-like particles containing ssRNA triggered BRM cell differentiation in the absence of cognate antigen, suggesting a low threshold of activation. In contrast, expansion of PCs in iBALTs took longer to develop and was critically dependent on CD4 T cells. Our work demonstrates that spatially distinct mechanisms evolved to support pulmonary secondary PC responses, and it reveals a specialized function for BRM cells as guardians of the alveoli. |