Anti-CD3D monoclonal antibody, clone VDIU2 [PE]

The behaviour of polycrystalline cadmium in different oxidative atmospheres was investigated. The interactions between cadmium and O2, CO2, water, and mixtures of these were studied. The cadmium sample was only reactive towards oxygen. A progressive growth of the O1s signal as a function of O2 exposure was observed, together with a shift in the Cd3d and Cd MNN peaks towards the positions reported for CdO. The O1s spectra show the presence of several components in the range of exposures analysed and the best fit of the experimental signals is obtained for the components at 529.3 eV and 531.3 eV. The signal at lower binding energy is characteristic of O2- in the oxide state, while the component at higher binding energy could be due to either chemisorbed oxygen or oxygen in a non-equivalent site in the oxide structure.

T cells recognize antigens via their cell surface TCR and are classified as either alpha beta or gamma delta depending on the variable chains in their TCR, alpha and beta or gamma and delta, respectively. Both alpha beta and gamma delta TCRs also contain several invariant chains, including CD3 delta, which support surface TCR expression and transduce the TCR signal. Mutations in variable chains would be expected to affect a single T cell lineage, while mutations in the invariant chains would affect all T cells. Consistent with this, all CD3 delta-deficient patients described to date showed a complete block in T cell development. However, CD3 delta-KO mice have an alpha beta T cell-specific defect. Here, we report 2 unrelated cases of SCID with a selective block in alpha beta but not in gamma delta T cell development, associated with a new splicing mutation in the CD3D gene. The patients' T cells showed reduced CD3D transcripts, CD3 delta proteins, surface TCR, and early TCR signaling. Their lymph nodes showed severe T cell depletion, recent thymus emigrants in peripheral blood were strongly decreased, and the scant alpha beta T cells were oligoclonal. T cell-dependent B cell functions were also impaired, despite the presence of normal B cell numbers. Strikingly, despite the specific loss of alpha beta T cells, surface TCR expression was more reduced in gamma delta than in alpha beta T cells. Analysis of individuals with this CD3D mutation thus demonstrates the contrasting CD3 delta requirements for alpha beta versus gamma delta T cell development and TCR expression in humans and highlights the diagnostic and clinical relevance of studying both TCR isotypes when a T cell defect is suspected.