Disclosed are devices and methods for analyzing a fluid cell containing sample. The devices are composed of a solid substrate, microfabricated to define at least one sample inlet port and a mesoscale flow system. The mesoscale flow system includes a sample flow channel, extending from the inlet port, and a cell handling region for treating cells disposed in fluid communication with the flow channel. The devices may further include a component for inducing flow of cells in the sample through the flow system. In one embodiment, the cell-handling region may include a cell lysis component to enable the lysis of cells in the sample, prior to, e.g., the detection of an intracellular component in the cell sample. In another embodiment, the cell handling region may have a cell capture region, with binding sites which reversibly bind to a specific population of cells in the cell sample, to permit the isolation of the specific cell population from the sample. The devices can be utilized in a wide range of automated sensitive and rapid tests for the analysis of a fluid cell containing sample.