Membrane protein GARP is a receptor for latent TGF-β on the surface of activated human Treg
✍ Scribed by Julie Stockis; Didier Colau; Pierre G. Coulie; Sophie Lucas
- Publisher
- John Wiley and Sons
- Year
- 2009
- Tongue
- English
- Weight
- 369 KB
- Volume
- 39
- Category
- Article
- ISSN
- 0014-2980
No coin nor oath required. For personal study only.
✦ Synopsis
Human Treg and Th clones secrete the latent form of TGF-b, in which the mature TGF-b protein is bound to the latency-associated peptide (LAP), and is thereby prevented from binding to the TGF-b receptor. We previously showed that upon TCR stimulation, human Treg clones but not Th clones produce active TGF-b and bear LAP on their surface. Here, we show that latent TGF-b, i.e. both LAP and mature TGF-b, binds to glycoprotein A repetitions predominant (GARP), a transmembrane protein containing leucine rich repeats, which is present on the surface of stimulated Treg clones but not on Th clones. Membrane localization of latent TGF-b mediated by binding to GARP may be necessary for the ability of Treg to activate TGF-b upon TCR stimulation. However, it is not sufficient as lentiviral-mediated expression of GARP in human Th cells induces binding of latent TGF-b to the cell surface, but does not result in the production of active TGF-b upon stimulation of these Th cells.