Transgenic mice with a gamma 2b transgene were produced to investigate whether gamma 2b can replace mu in the development of B lymphocytes. Transgenic gamma 2b is present on the surface of B cells. Young transgenic mice have a dramatic decrease in B cell numbers, however, older mice have almost normal B cell numbers. Strikingly, all gamma 2b-expressing B cells in the spleen also express mu. The...

BACKGROUND Comparison and evaluation of molecular diagnostic assays for the detection and quantification of hepatitis C virus (HCV) RNA have been limited by the lack of RNA controls and calibrators. Armored RNA technology is a means for producing RNA that is completely protected from plasma ribonucleases. This method produces recombinant pseudoviral particles that are noninfectious and contain ...

Transport of macromolecules between the cell nucleus and cytoplasm occurs through the nuclear pores and is mediated by soluble carriers known as karyopherins (Kaps), transportins, importins, or exportins. We report that Kap 2B (transportin-2) forms complexes with the mRNA export factor TAP in the presence of RanGTP, as shown by coimmunoprecipitation from HeLa cells. The interaction strictly dep...

Human mast cells express functional A(2A) and A(2B) adenosine receptors. However, only stimulation of A(2B), not A(2A), leads to secretion of interleukin (IL)-4, an important step in adenosine receptor-mediated induction of IgE synthesis by B-cells. In this study, we investigate intracellular pathways that link stimulation of A(2B) receptors to IL-4 up-regulation in HMC-1 mast cells. Both A(2A)...

gamma 2b transgenic mice have a severe B cell defect, apparently caused by strong feedback inhibition of endogenous H-gene rearrangement coupled with an inability of gamma 2b to provide the survival/maturation functions of mu. A unique gamma 2b transgenic line, named the C line, was found to permit B cell development. When the C line is crossed with a mu-membrane knockout line, gamma 2b+ B cell...