A second TCRδ locus in Galliformes uses antibody-like V domains: insight into the evolution of TCRδ and TCRμ genes in tetrapods.

A Second TCRd Locus in Galliformes Uses Antibody-like V Domains: Insight into the Evolution of TCRd and TCRm Genes in Tetrapods

A Model for the Evolution of the Mammalian T-cell Receptor α/δ and μ Loci Based on Evidence from the Duckbill Platypus

The specific recognition of antigen by T cells is critical to the generation of adaptive immune responses in vertebrates. T cells recognize antigen using a somatically diversified T-cell receptor (TCR). All jawed vertebrates use four TCR chains called α, β, γ, and δ, which are expressed as either a αβ or γδ heterodimer. Nonplacental mammals (monotremes and marsupials) are unusual in that their ...

RUNX1 as a recombinase cofactor

The regulation of TCR rearrangements, particularly of TCRδ and TCRβ, plays a decisive role in lymphoid differentiation and oncogenic transformation. Somatic assembly of TCR loci is established through V(D)J recombination during lymphocyte development. All V, (D) and J gene segments are flanked with recombination signal sequences (RSS) which are composed of conserved heptamer and nonamer motifs ...

Platypus TCRμ provides insight into the origins and evolution of a uniquely mammalian TCR locus.

TCRμ is an unconventional TCR that was first discovered in marsupials and appears to be absent from placental mammals and nonmammals. In this study, we show that TCRμ is also present in the duckbill platypus, an egg-laying monotreme, consistent with TCRμ being ancient and present in the last common ancestor of all extant mammals. As in marsupials, platypus TCRμ is expressed in a form containing...

γδ T Cells Are Required for M2 Macrophage Polarization and Resolution of Ozone-Induced Pulmonary Inflammation in Mice

We examined the role of γδ T cells in the induction of alternatively activated M2 macrophages and the resolution of inflammation after ozone exposure. Wildtype (WT) mice and mice deficient in γδ T cells (TCRδ-/- mice) were exposed to air or to ozone (0.3 ppm for up to 72h) and euthanized immediately or 1, 3, or 5 days after cessation of exposure. In WT mice, M2 macrophages accumulated in the lu...