To study interleukin-7 (IL-7) in early thymocyte development, we generated mice transgenic (Tg) for the IL-7 gene under control of the lck proximal promoter. Founder line TgA, with the lowest level of IL-7 overexpression, showed enhanced alphabeta T-cell development. In contrast, in the highest overexpressing founder line, TgB, alphabeta T-cell development was disturbed with a block at the earl...

Staphylococcus aureus is a major mastitis-causing pathogen in cattle. The chronic nature of bovine staphylococcal mastitis suggests that some products or components of S. aureus may interfere with the development of protective immunity. One class of molecules that could be involved are superantigens (SAgs). Although a significant number of mastitis isolates produce SAgs, the effect of these mol...

The nuclear hormone receptor retinoic acid receptor-related orphan receptor gamma t (RORgamma t) is required for the generation of T helper 17 cells expressing the proinflammatory cytokine interleukin (IL)-17. In vivo, however, less than half of RORgamma t(+) T cells express IL-17. We report here that RORgamma t(+) T alphabeta cells include Foxp3(+) cells that coexist with IL-17-producing RORga...

The innate immune system uses different mechanisms to respond to infectious pathogens. Experiments evaluating the requirements for a type 1 IFN (IFN-alphabeta) response to lymphocytic choriomeningitis virus (LCMV) resulted in the surprising discovery that mice deficient in B and T cell development, i.e., RAG-deficient and SCID, had profoundly reduced levels of IFN-alphabeta in serum and spleen,...

Photosystem II is a reaction center protein complex located in photosynthetic membranes of plants, algae, and cyanobacteria. Using light energy, photosystem II catalyzes the oxidation of water and the reduction of plastoquinone, resulting in the release of molecular oxygen. A key component of photosystem II is cytochrome b559, a membrane-embedded heme protein with an unknown function. The cytoc...

Type I IFN (IFN-alphabeta), which is produced rapidly in response to infection, plays a key role in innate immunity and also acts as a stimulus for the adaptive immune response. We have investigated how IFN-alphabeta induces cross-priming, comparing CD8+ T cell responses generated against soluble protein Ags in the presence or absence of IFN-alphabeta. Injection of IFN-alpha was found to prolon...

Previously, we have reported that neutralization of surface lymphotoxin (LT-alphabeta) in mice which expressed an LT-beta receptor-Fc fusion protein, driven by the cytomegalovirus promoter, resulted in an array of anatomic abnormalities. We now report that mice which express a tumor necrosis factor (TNF) receptor p60-Fc fusion protein (which neutralizes TNF and soluble LT-alpha3 activity) devel...

Vanilloid (VR1) and purinergic (P2X) receptors are found in cranial afferent neurons in nodose ganglia and their central terminations within the solitary tract nucleus (NTS), but little is known about their function. We mechanically dissociated dorsomedial NTS neurons to preserve attached native synapses and tested for VR1 and P2X function primarily in spindle-shaped neurons resembling intact s...

The editing reactions catalyzed by aminoacyl-tRNA synthetases are critical for the faithful protein synthesis by correcting misactivated amino acids and misaminoacylated tRNAs. We report that the isolated editing domain of leucyl-tRNA synthetase from the deep-rooted bacterium Aquifex aeolicus (alphabeta-LeuRS) catalyzes the hydrolytic editing of both mischarged tRNA(Leu) and minihelix(Leu). Wit...

The rod photoreceptor phosphodiesterase (PDE) is unique among all known vertebrate PDE families for several reasons. It is a catalytic heterodimer (alphabeta); it is directly activated by a G-protein, transducin; and its active sites are regulated by inhibitory gamma subunits. Rod PDE binds cGMP at two noncatalytic sites on the alphabeta dimer, but their function is unclear. We show that transd...