Mucin overproduction is a hallmark of nontypeable Haemophilus influenzae (NTHi) infections. The molecular mechanisms underlying up-regulation of mucin in NTHi infections especially during the initial phase remain unknown. Here we show that P6, a 16-kDa outer membrane lipoprotein well conserved in NTHi, up-regulates MUC5AC mucin gene transcription in vitro and in vivo. Moreover, P6 induces MUC5AC transcription via TLR2-MyD88-IRAK1-TRAF6-TAK1-dependent p38 MAPK-AP1 and IKKbeta-IkappaBalpha-NF-kappaB signaling pathways. This study may bring new insights into the molecular pathogenesis of NTHi-induced infections and lead to novel therapeutic intervention for inhibiting mucin overproduction in patients with NTHi infections.

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http://dx.doi.org/10.1016/j.bbrc.2004.09.157DOI Listing

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