A tissue proteomics process is presented where hepatocyte cell isolation in combination with two-dimensional (2-D) gel electrophoresis and mass spectrometric identification were used to annotate the liver proteome. Laser microdissection of 8 microm liver tissue sections was performed and protein expression profiling was compared using a variety of quantities of input cells, and gel separation conditions. The 30 microm diameter laser generated the highest protein yields from the polymer coated caps following microsolubilization. We found that 6000 laser pulses (approximately 7200 hepatocytes) were required in order to generate high-resolution gel maps. Within homogeneous tissue samples, this could be accomplished in a total cycle time of 20 min using an automated dissection procedure. Close to 1000 high-quality gel annotations were generated from the corresponding 2-D gel expression profiles which matched closely the corresponding patterns of analytical-scale liver preparations detected by silver staining.