A ring $R$ with an automorphism $sigma$ and a $sigma$-derivation $delta$ is called $delta$-quasi-Baer (resp., $sigma$-invariant quasi-Baer) if the right annihilator of every $delta$-ideal (resp., $sigma$-invariant ideal) of $R$ is generated by an idempotent, as a right ideal. In this paper, we study Baer and quasi-Baer properties of skew PBW extensions. More exactly, let $A=sigma(R)leftlangle x...

The regional variation in the intraepithelial lymphocytes (IELs) in the small intestine was examined in BALB/c male and female mice and C3H/He and C57BL/6 male mice. The small intestines were taken from 11 to 12-week-old mice and divided equally into 3 parts (the proximal, middle and distal parts). IELs were isolated from each part of the intestine and analyzed with flow cytometer. The number o...

Wild-type (WT) and targeted-mutant mice incapable of making alphabeta T cells, gammadelta T cells, class I major histocompatibility complex (MHC), class II MHC, interferon (IFN)-gamma, or inducible nitric oxide synthase (NOS2), were infected with Mycobacterium tuberculosis (Mtb) by aerosol, and monitored over time for their ability to (a) control infection, (b) develop histopathology at sites o...

The antiapoptotic function of the interleukin-7 (IL-7) receptor is related to regulation of three members of the Bcl2 family: synthesis of Bcl2, phosphorylation of Bad, and cytosolic retention of Bax. Here we show that, in an IL-7-dependent murine T-cell line, different regions of the IL-7 receptor initiate the signal transduction pathways that regulate these proteins. Both Box1 and Y449 are re...

BACKGROUND Double negative CD3(+)4(-)8(-) TCR alphabeta splenic cells (DNCD3) can suppress the immune responses to allo and xenografts, infectious agents, tumors, and some autoimmune disorders. However, little is known about their role in autoimmune diabetes, a disease characterized by the reduction of insulin production subsequent to destruction of pancreatic beta-cells by a polyclonal populat...

Sensitization is a critical unresolved challenge in transplantation. We show for the first time that blockade of CD154 alone or combined with T-cell depletion prevents sensitization. Allogeneic skin grafts were rejected by recipients treated with anti-alphabeta T-cell receptor (TCR), anti-CD154, anti-OX40L, or anti-inducible costimulatory pathway (ICOS) mAb alone with a kinetic similar to untre...

Signals from the IL-7R are uniquely required for T cell development and maintenance, despite the resemblance of IL-7R to other cytokine receptors and the apparent sharing of common signaling pathways. This unique requirement could either reflect unique expression of IL-7R or IL-7, or it could indicate that the IL-7R delivers unique signals. To determine whether the IL-7R provided unique signals...

Some T lymphocytes express the CD94 Ag, which is known to form heterodimers with members of the NKG2 family. We have studied the expression pattern and function of CD94 heterodimers in different alphabeta or gammadelta T cell clones. Most of the CD94+NKG2A- T cells have a low to intermediate expression of CD94 Ag. The cross-linking of the CD94/NKG2 heterodimer in one of these CD8 alphabeta CD94...

The structure of R-phycoerythrin (R-PE) from the red alga Griffithsia monilis was solved at 1.90-A resolution by molecular replacement, using the atomic coordinates of cyanobacterial phycocyanin from Fremyella diplosiphon as a model. The crystallographic R factor for the final model is 17.5% (Rfree 22.7%) for reflections in the range 100-1.90 A. The model consists of an (alphabeta)2 dimer with ...

Many viruses induce a strong T cell response that contributes to the elimination of infected cells presenting viral peptides by MHC molecules. The structure and expression of genes encoding molecules homologous to mammalian alphabeta TCRs have been recently characterized in rainbow trout and in several teleost species, but the alphabeta T cell response against pathogens has not been directly de...