In an in vitro model of primary human lung microvascular endothelial cells (LMECs), Bauer et al. (2023) [42] found that although LMECs are rarely and abortively infected by IAV, high levels of pro-inflammatory cytokines such as IL-6, IL-1, IP-10, IFN-β, IFN-λ, and IFN-γ are produced in response to infection, suggesting that in a natural infection endothelial cells can potentially contribute to systemic inflammation. Here, IL6 is linked to infection.