2B4 (CD244) Is Expressed and Functional on Human Eosinophils

Department of Pharmacology, School of Pharmacy, Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem 91120, Israel.
The Journal of Immunology (Impact Factor: 4.92). 02/2005; 174(1):110-8. DOI: 10.4049/jimmunol.174.1.110
Source: PubMed


Eosinophils are present in parasitic, allergic, various immunological, and malignant disorders as well as in a variety of idiopathic hypereosinophilic syndromes. However, their exact role in some of these conditions remains elusive. They can be activated both in vivo and in vitro by various agonists, such as Igs, lipid mediators, and cytokines. By phenotyping the surface of the eosinophils, it may be possible to better define their function(s) in different pathophysiological settings. In the present work we screened eosinophils with a panel of Abs recognizing CD2 subfamily receptors usually present on a number of hemopoietic cells. We have demonstrated that human peripheral blood eosinophils, but not basophils or neutrophils, express NTB-A. In addition eosinophils express 2B4, CD84, CD58, and CD48, but not signaling lymphocytic activation molecule or CD2, on their surface (FACS). Cross-linking of 2B4 on eosinophils elicited a significant release of eosinophil peroxidase (30 min), IFN-gamma, and IL-4 (18 h). Moreover, activation of eosinophils via 2B4 induced eosinophil-mediated cytotoxicity toward two malignant cell lines, i.e., mouse mastocytoma P815 and EBV-infected 721.221 B cell lines. Cross-linking of 2B4 on the surface of eosinophils or pervenadate treatment elicited ERK and tyrosine phosphorylation, respectively. Furthermore, we showed that eosinophils express slam-associated protein. The demonstration that human eosinophils express a functional 2B4 receptor indicates a broader role for these cells in health and disease.

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    • "). Eosinophils express various receptors for activating stimuli such as IL-2, C5a and PAF, interferon (IFN)-γ (Neves et al., 2008), IL-3, IL-5, GM-CSF, chemokine receptor 3 (CCR3), RANTES (Regulated on Activation, Normal T Expressed and Secreted) (Gregory et al., 2003) and the immunoglobulin A (Decot et al., 2005), which cause them to degranulate. Moreover they also express CD48, 2B4 (Munitz et al., 2005), pattern recognition receptors (PRRs) (Kvarnhammar and Cardell, 2012) and histamine receptors that signal via various mechanisms/pathways (summarized in (Davoine and Lacy, 2014). This would indicate their capacity to be involved in several kinds of pathologies. "
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