Influenza A viruses (IAV) mutate rapidly and cause seasonal epidemics
and occasional pandemics, which result in substantial number of patient
visits to the doctors and even hospitalizations. We aimed here to
identify inflammatory proteins, which levels correlated to clinical
severity of the disease. For this we analysed 102 cytokines and growth
factors in human nasopharyngeal aspirate (NPA) samples of 27
hospitalized and 27 outpatients diagnosed with influenza A(H1N1)pdm09
virus infection. We found that the relative levels of monocyte
differentiation antigen CD14, lipocalin-2 (LCN2), C-C-motif chemokine 20
(CCL20), CD147, urokinase plasminogen activator surface receptor
(uPAR), pro-epidermal growth factor (EGF), trefoil factor 3 (TFF3), and
macrophage migration inhibitory factor (MIF) were significantly lower
(p<0.008), whereas levels of retinol-binding protein 4 (RBP4), C-X-C
motif chemokine 5 (CXCL5), interleukin-8 (IL-8), complement factor D
(CFD), adiponectin, and chitinase-3-like 1 (CHI3L1) were significantly
higher (p<0.008) in NPA samples of hospitalized than non-hospitalized
patients. While changes in CD14, LCN2, CCL20, uPAR, EGF, MIF, CXCL5,
IL-8, adiponectin and CHI3L1 levels have already been correlated with
severity of IAV infection in mice and humans, our study is the first to
describe association of CD147, RBP4, TFF3, and CFD with hospitalization
of IAV-infected patients. Thus, we identified local innate immune
profiles, which were associated with the clinical severity of influenza
infections.