First Author | McMillan SJ | Year | 2014 |
Journal | Immunol Lett | Volume | 160 |
Issue | 1 | Pages | 11-16 |
PubMed ID | 24698729 | Mgi Jnum | J:288980 |
Mgi Id | MGI:6435607 | Doi | 10.1016/j.imlet.2014.03.008 |
Citation | McMillan SJ, et al. (2014) Siglec-F-dependent negative regulation of allergen-induced eosinophilia depends critically on the experimental model. Immunol Lett 160(1):11-16 |
abstractText | Siglec-8 and siglec-F are paralogous membrane proteins expressed on human and murine eosinophils respectively. They bind similar sialylated and sulphated glycans and mediate eosinophil apoptosis when cross-linked with antibodies or glycan ligands. In models of allergic eosinophilic airway inflammation, siglec-F was shown previously to be important for negatively regulating eosinophilia. It was proposed that this was due to siglec-F-dependent apoptosis, triggered via engagement with ligands that are upregulated on bronchial epithelium. Our aim was to further investigate the functions of siglec-F by comparing two commonly used models of ovalbumin-induced airway inflammation that differ in the dose and route of administration of ovalbumin. In confirmation of published results, siglec-F-deficient mice had enhanced lung tissue eosinophilia in response to intranasal ovalbumin delivered every other day. However, following aerosolised ovalbumin delivered daily, there was no influence of siglec-F deficiency on lung eosinophilia. Expression of siglec-F ligands in lung tissues was similar in both models of allergen induced inflammation. These data demonstrate that siglec-F-dependent regulation of eosinophilia is subtle and depends critically on the model used. The findings also indicate that mechanisms other than ligand-induced apoptosis may be important in siglec-F-dependent suppression of eosinophilia. |