Abstract
Selectins guide the traffic of activated T-cells through the blood stream by mediating their tethering and rolling onto inflamed endothelium, in this way acting as beacons to help navigate them to sites of inflammation. Here, we present a comprehensive analysis of E-selectin ligands expressed on activated human T-cells. We identified several novel glycoproteins that function as E-selectin ligands. Specifically, we compared the role of P-selectin glycoprotein ligand-1 (PSGL-1) and CD43, known E-selectin ligands, to CD44, a ligand that has not previously been characterized as an E-selectin ligand on activated human T-cells. We showed that CD44 acts as a functional E-selectin ligand when expressed on both CD4+ and CD8+ T-cells. Moreover, the CD44 protein carries a binding epitope identifying it as hematopoietic cell E- and/or L-selectin ligand (HCELL). Furthermore, by knocking down these ligands individually or together in primary activated human T-cells, we demonstrated that CD44/HCELL, and not CD43, cooperates with PSGL-1 as a major E-selectin ligand. Additionally, we demonstrated the relevance of our findings to chronic autoimmune disease, by showing that CD44/HCELL and PSGL-1, but not CD43, from T-cells isolated from psoriasis patients, bind E-selectin.
| Original language | English (US) |
|---|---|
| Journal | Frontiers in Immunology |
| Volume | 8 |
| Issue number | MAY |
| DOIs | |
| State | Published - May 3 2017 |
Bibliographical note
KAUST Repository Item: Exported on 2020-10-01Acknowledged KAUST grant number(s): CRG2_R2_13_MERZ_KAUST_1
Acknowledgements: This work was supported by the King Abdullah University of Science and Technology (KAUST) Faculty Baseline Research Funding Program as well as a Competitive Research Grant (CRG2_R2_13_MERZ_KAUST_1) to JM. The authors would like to thank Dr. Samir M. Hamdan for discussions regarding SPR studies and Ms. Samar A. Rostom for her support in the management of the lab. The authors would also like to thank Carolyn Unck from the Academic Writing Services at KAUST for editing the manuscript. In addition, a special thanks to Dr. Aswini K. Panigrahi from the Bioscience Core Lab facility for the mass spectrometry assistance and the rest of the members of the Cell Migration and Signaling Laboratory for their support.
