|Detection of TSLP R in NS0 Mouse Cell Line Transfected with Human TSLP R by Flow Cytometry. NS0 mouse myeloma cell line transfected with human TSLP R was stained with Mouse Anti-Human TSLP R Alexa Fluor® 488‑conjugated Monoclonal Antibody (Catalog # FAB981G, filled histogram) or isotype control antibody (Catalog # IC002G, open histogram). View our protocol for Staining Membrane-associated Proteins.|
TSLP R, also named Delta (1) and CRLM-2 (2) (Cytokine Receptor-Like Module-2), was originally cloned as a novel type 1 cytokine receptor with similarity to the common gamma chain. It was subsequently identified to be a subunit of the cellular receptor for the IL-7-like cytokine TSLP and termed TSLP R (3). The human TSLP R cDNA encodes a 371 amino acid (aa) residue type 1 membrane protein with a 22 aa residue signal peptide, a 210 aa residue extracellular domain, a 20 aa residue transmembrane domain, and a 119 aa residue cytoplasmic domain (4, 5). The extracellular region contains two fibronectin type III-like domains and a WSXWS-like motif. The cytoplasmic domain contains a membrane-proximal box 1 motif that is known to be important for association with JAKs (4). Human TSLP R displays 39% identity to mouse TSLP R and 24% identity to the common gamma receptor (4). An alternatively spliced mRNA variant encoding a soluble TSLP R has also been reported in mouse (2). TSLP R expression is ubiquitous in the immune and hematopoietic cells, but is up-regulated in Th2-skewed cells. Cells expressing TSLP R alone bind TSLP with low affinity. Co-expression of TSLP R and IL-7 R alpha is required for high-affinity TSLP binding and signal transduction (3‑6). The TSLP R and IL-7 R alpha are co‑expressed primarily on monocytes and dendritic cells and at lower levels in lymphoid cells. TSLP has been shown to induce the release of T cell-attracting chemokines from monocytes and enhance the maturation of CD11c+ dendritic cells (5).