The Fc receptor on NK cells, FcγRIIIA (CD16), has been extensively studied for its role in mediating antibody-dependent cellular cytotoxicity (ADCC). A homozygous missense mutation in CD16 (encoding a L66H substitution) is associated with severe herpesvirus infections in rare patients. Here, we identified a new patient with this CD16 mutation and compared the patient's NK cells to those of the ...

Intracellular protein interaction domains are essential for eukaryotic signaling. In T cells, the CD2BP2 adaptor binds two membrane-proximal proline-rich motifs in the CD2 cytoplasmic tail via its GYF domain, thereby regulating interleukin-2 production. Here we present the structure of the GYF domain in complex with a CD2 tail peptide. Unlike SH3 domains, which use two surface pockets to accomm...

NMDA receptor channels are characterized by high Ca2+ permeability. It remains unclear whether extracellular Ca2+ could directly modulate channel gating and control Ca2+ influxes. We demonstrate a pore-blocking site external to the activation gate for extracellular Ca2+ and Cd2+, which has the same charge and radius as Ca2+ but is impermeable to the channel. The apparent affinity of Cd2+ or Ca2...

2-(3- indolyl) – 4,5 di phynyl imidazole.(IDPI) was used as a complexing agent in cloud point extraction for the first time and applied for selective pre-concentration of trace amounts of cadmium. The method is based on the extraction of cadmium at pH= 7.0 by using non-ionic surfactant Triton-X114 and 2-(3- indolyl) – 4,5 di phynyl imidazole. (IDPI) as a chelating agent. The adopted concentrati...

Introduction One of the more familiar examples of cell-cell recognition is that between T cells and an antigenpresenting cell, which consists of a complex array of interprotein interactions that are just beginning to be unravelled [ 1, 21. These interactions promote and support the recognition of foreign antigenic peptides bound to major histocompatibility proteins by specific T-cell receptor m...

Adoptive transfer of Tumor Infiltrating Lymphocytes (TIL), T-cell receptor (TCR)-transduced PBL and Chimeric Antigen Receptor (CAR)-transduced PBL have proven to be clinically effective. CARs have evolved by introducing cytoplastic costimulatory domains. Higher cytokine secretion and longer persistence of CARtransduced T-cells in vivo imply important roles of costimulatory signals. In contrast,...

We have recently identified a dominant wave of CD4-CD8- (double-negative [DN]) thymocytes in early murine fetal development that express low affinity Fc gamma receptors (Fc gamma RII/III) and contain precursors for Ti alpha/beta lineage T cells. Here we show that Fc gamma RII/III is expressed in very immature CD4low single-positive (SP) thymocytes and that Fc gamma RII/III expression is downreg...

Crosslinking of CD2 antigen on T lymphocytes and natural killer (NK) cells leads to a rise in cytoplasmic-free Ca2+ concentration ([Ca2+]i). However, CD2 seems unlikely to interact directly with the second messenger pathways since signaling via CD2 is poor in T cells that lack the T cell receptor (TCR) and is absent in L cells or insect cells that express CD2. In contrast, NK cells that are als...

Major histocompatibility complex-unrestricted lymphokine-activated killer (LAK) cells have been proposed as therapy for a variety of hematologic malignancies. Because these cells recognize and kill their targets independently of their antigen specific CD3 receptor, it is unclear how they might discriminate between normal and malignant cells. We now propose one such mechanism for the selective k...

Transmembrane signaling of normal human T cells was explored with mAbs directed at TCR, CD2, CD4, CD5, or CD8 antigens and highly purified CD4+ T cells and CD8+ T cells. Our experiments explicitly show that: (a) crosslinkage of TCR with the CD2 antigen, and not independent crosslinking of TCR and of CD2 antigen or crosslinking of either protein with the CD4 or CD8 antigen induces significant pr...