https://www.selleckchem.com/products/kpt-9274.html Likewise, CDR3 alone did not discriminate against MHC binding, suggesting VDJ recombination together with Vα/Vβ pairing determine their MHC-independent specificity for CD155. The structures of A11 and B12A TCR are nearly identical to those of MHC-restricted TCR, including the conformations of CDR1 and 2. Mutational analysis, together with negative-staining electron microscopy images, showed that the CDR regions of A11 and B12A recognized epitopes on D1 domain of CD155, a region also involved in CD155 binding to poliovirus and Tactile in human. Taken together, MHC-independent TCRs adopt canonical TCR structures to recognize native Ags, highlighting the importance of thymic selection in determining TCR ligand specificity. Copyright © 2020 by The American Association of Immunologists, Inc.LILRB1 is a highly polymorphic receptor expressed by subsets of innate and adaptive immune cells associated with viral and autoimmune diseases and targeted by pathogens for immune evasion. LILRB1 expression on human NK cells is variegated, and the frequency of LILRB1+ cells differs among people. However, little is known about the processes and factors mediating LILRB1 transcription in NK cells. LILRB1 gene expression in lymphoid and myeloid cells arises from two distinct promoters that are separated by the first exon and intron. In this study, we identified a polymorphic 3-kb region within LILRB1 intron 1 that is epigenetically marked as an active enhancer in human lymphoid cells and not monocytes. This region possesses multiple YY1 sites, and complexes of the promoter/enhancer combination were isolated using anti-YY1 in chromatin immunoprecipitation-loop. CRISPR-mediated deletion of the 3-kb region lowers LILRB1 expression in human NKL cells. Together, these results indicate the enhancer in intron 1 binds YY1 and suggest YY1 provides a scaffold function enabling enhancer function in regulating LILRB1 gene transcription in human NK ce