| abstract |
The invention demonstrates that the XBP-1 transcription factor is a regulator of hepatocyte growth, differentiation of plasma cells and the activity of subgroups of T cells. Methods for identifying modulators of hepatocyte growth, differentiation of plasma cells are provided. and / or activity of subgroups of T cells, using indicator compositions containing XBP-1 or XBP-1 deficient cells. Methods are also provided to modulate hepatocyte growth, differentiation of plasma cells and / or activity of subgroups of T cells (eg, production of Th2 cytokines) using agents that modulate the activity of XBP-1. Methods for diagnosing disorders associated with aberrant hepatocyte growth, aberrant differentiation of plasma cells and / or aberrant activity of subgroups of T cells, by evaluating a change in the expression of XBP-1, are also provided. The invention also offers cells, animals and embryos deficient in XBP-1 as well as kits for the methods of the invention. |