Neuropeptides SP and CGRP Diminish the Moraxella catarrhalis Outer Membrane Vesicle- (OMV-) Triggered Inflammatory Response of Human A549 Epithelial Cells and Neutrophils

Figure 4

Flow cytometric analysis of antiapoptotic effects of SP and CGRP towards A549 cell death induced by M. catarrhalis OMVs. (a) The A549 cells were treated with various stimulants for 24 h of incubation, processed, stained with Annexin V and PI antibodies, and analyzed using Muse Cell Analyzer (Merck). The upper panel refers to untreated control cells and positive control (5 mM H₂O₂). The lower panel refers to the cells treated with OMVs 100 μg/ml alone or in the presence of 10⁻⁸ M of SP or CGRP. Representative data from at least two independent experiments are shown. (b) Cell surface expression of CEACAM1 in A549 obtained from 1-day postconfluent phase of growth. A549 cells were stained for CEACAM1 with mAb clone 283340 as primary antibody or isotype-matched control followed by Alexa Fluor 488-conjugated goat anti-mouse IgG superclonal secondary antibody. Subsequently, samples were measured by FACs. The data shown are representative of two independent but essentially the same experiments performed in duplicates.

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