| First Author | Cassard L | Year | 2012 |
| Journal | J Immunol | Volume | 189 |
| Issue | 6 | Pages | 2995-3006 |
| PubMed ID | 22908332 | Mgi Jnum | J:190233 |
| Mgi Id | MGI:5448474 | Doi | 10.4049/jimmunol.1200968 |
| Citation | Cassard L, et al. (2012) Fcgamma receptors inhibit mouse and human basophil activation. J Immunol 189(6):2995-3006 |
| abstractText | Besides high-affinity IgE receptors (FcepsilonRI), human basophils express activating (FcgammaRIIA) and inhibitory (FcgammaRIIB) low-affinity IgG receptors. IgG receptors (FcgammaR) were also found on mouse basophils, but not identified. We investigated in this study FcgammaR and the biological consequences of their engagement in basophils of the two species. We found the following: (1) that mouse basophils also express activating (FcgammaRIIIA) and inhibitory (FcgammaRIIB) low-affinity FcgammaR; (2) that activating FcgammaR can activate both human and mouse basophils, albeit with different efficacies; (3) that negative signals triggered by inhibitory FcgammaR are dominant over positive signals triggered by activating FcgammaR, thus preventing both human and mouse basophils from being activated by IgG immune complexes; (4) that the coengagement of FcepsilonRI with inhibitory and activating FcgammaR results in a FcgammaRIIB-dependent inhibition of IgE-induced responses of both human and mouse basophils; (5) that FcgammaRIIB has a similar dominant inhibitory effect in basophils from virtually all normal donors; and (6) that IL-3 upregulates the expression of both activating and inhibitory FcgammaR on human basophils from normal donors, but further enhances FcgammaRIIB-dependent inhibition. FcgammaR therefore function as a regulatory module, made of two subunits with antagonistic properties, that prevents IgG-induced and controls IgE-induced basophil activation in both mice and humans. |
