Anti-inflammatory effects of the new generation synthetic surfactant CHF5633 on <i>Ureaplasma</i>-induced cytokine responses in human monocytes

<p><b>Background:</b> Synthetic surfactants represent a promising alternative to animal-derived preparations in the treatment of neonatal respiratory distress syndrome. The synthetic surfactant CHF5633 has proven biophysical effectiveness and, moreover, demonstrated anti-inflammatory effects in LPS-stimulated monocytes. With ureaplasmas being relevant pathogens in preterm lung inflammation, the present study addressed immunomodulatory features on <i>Ureaplasma</i>-induced monocyte cytokine responses.</p> <p><b>Methods:</b><i>Ureaplasma parvum</i>-stimulated monocytes were exposed to CHF5633. TNF-α, IL-1β, IL-8, IL-10, TLR2 and TLR4 expression were analyzed using qPCR and flow cytometry.</p> <p><b>Results:</b> CHF5633 did not induce pro-inflammation, and did not aggravate <i>Ureaplasma</i>-induced pro-inflammatory cytokine responses. It suppressed <i>U. parvum</i>-induced intracellular TNF-α (p < 0.05) and IL-1β (p < 0.05) in neonatal monocytes and inhibited <i>Ureaplasma</i>-induced TNF-α mRNA (p < 0.05), TNF-α protein (p < 0.001), and IL-1β (p = 0.05) in adult monocytes. <i>Ureaplasma</i>-modulated IL-8, IL-10, TLR2 and TLR4 were unaffected.</p> <p><b>Conclusion:</b> CHF5633 does neither act pro-apoptotic nor pro-inflammatory in native and <i>Ureaplasma</i>-infected monocytes. Suppression of <i>Ureaplasma</i>-induced TNF-α and IL-1β underlines anti-inflammatory features of CHF5633.