Recombinant Human LILRB2/CD85d/ILT4 Fc Avi-tag Protein, CF

Recombinant Human LILRB2/CD85d/ILT4 Fc Avi-tag Protein, CF Summary

Product Specifications

Product Datasheets

Carrier Free

CF stands for Carrier Free (CF). We typically add Bovine Serum Albumin (BSA) as a carrier protein to our recombinant proteins. Adding a carrier protein enhances protein stability, increases shelf-life, and allows the recombinant protein to be stored at a more dilute concentration. The carrier free version does not contain BSA.

In general, we advise purchasing the recombinant protein with BSA for use in cell or tissue culture, or as an ELISA standard. In contrast, the carrier free protein is recommended for applications, in which the presence of BSA could interfere.

Background: LILRB2/CD85d/ILT4

The immunoglobulin-like transcript (ILT) comprise a family of activating and inhibitory type immunoreceptors whose genes are located in the same locus that encodes killer cell Ig-like receptors (KIR) (1-3). ILT4, also known as LIR-2 and LILRB2, is a type I transmembrane protein expressed primarily on monocytes and dendritic cells (DC) (4). Human ILT4 is produced as a 598 amino acid (aa) precursor including a 21 aa signal sequence, a 440 aa extracellular domain (ECD), a 21 aa transmembrane segment, and a 116 aa cytoplasmic domain. The ECD contains four Ig-like domains, and the cytoplasmic domain contains three immunoreceptor tyrosine-based inhibitory motifs (ITIM) (5). The ECD of human ILT4 shares 76% aa identity with chimpanzee ILT4 and 74%, 81%, 33%, 52%, 77%, 61%, and 64 % aa identity with human ILT1, 2, 3, 5, 6, 7, and 8, respectively. ILT4 binds to classical MHC I proteins as well as the non-classical HLA-G1 and HLA-F molecules (5-9). It competes with CD8 alpha for MHC I binding but does not compete with KIR2DL1 (7). Ligation of ILT4 induces Tyr phosphorylation within its cytoplasmic ITIMs, a requirement for association with SHP-1 (4, 6). Activation of ILT4 inhibits signaling through Fc gamma RI (4) and Fc epsilon RI (6) and causes DC to become tolerogenic by down-regulation of co‑stimulatory molecules (10, 11). ILT4 mediates tolerogenic DC‑induced CD4⁺ T cell energy in vitro and in vivo (10-12). Our Avi-tag Biotinylated human LILRB2/CD85d/ILT4 features biotinylation at a single site contained within the Avi-tag, a unique 15 amino acid peptide. Protein orientation will be uniform when bound to streptavidin-coated surface due to the precise control of biotinylation and the rest of the protein is unchanged so there is no interference in the protein's bioactivity.

Related Research Areas

• Angiopoietins, Angiopoietin-like Proteins, and Receptors
• B Cell Activation
• Co-stimulatory and Co-inhibitory Molecules
• Dendritic Cell ITIM/ITAM Immunoreceptors
• Dendritic Cell Pathogen Recognition/Uptake
• ITIM/ITAM Immunoreceptors and Related Molecules
• Monocyte Markers
• Search Immune Checkpoint Targets
• T Cell Antigen Recognition