Biochemical Characterization of Human IL-15 Receptor-alpha
Year: 2013
Type: article
Abstract: The cytokine IL-15 is a growth, mobilization and activation factor for NK cells, CD8+ T cells and intraepithelial T lymphocytes. IL-15 activates target cells via a heterodimeric receptor consisting of a beta subunit (CD122) and a gamma chain (CD132) common to the IL-2 receptor. Recently, we demonstrated that in vivo in both mice and humans IL-15 circulates as a heterodimeric cytokine in a noncovalently associated 1:1 complex with a soluble processed form of the IL-15 receptor alpha subunit (IL-15Ra). Soluble IL-15Ra is generated by proteolytic cleavage close to the transmembrane region of the membrane spanning molecule non-covalently linked to IL-15. To identify the cleavage site and other potential post-translational modifications we purified soluble IL-15Ra from the supernatant of stable HEK293-derived human cell lines overproducing IL-15/IL-15Ra heterodimers using reverse phase HPLC. MS analysis and Edman sequencing of sIL-15Ra and its Lys-C peptides allowed identification of C-terminus sequence and thereby the cleavage site. Multiple O-glycosylation sites were identified by mass spectrometry of sIL-15Ra and its Lys-C peptides. Contract No. HHSN261200800001E
Source: Europe PMC (PubMed Central)
Language: English
Subfield: Oncology
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W2397954623