ABSTRACT
Gene expression analysis provides an insight into the unique and defining biomolecular characteristics of a given cell type. However, heterogeneous cellular compositions hinder gene analysis studies from most tissue samples. The laser microdissection (LMD) technique allows for the unambiguous isolation of a desired cell population. However, preserving RNA integrity can be challenging because of the deliberately limited amount of starting material, sometimes as little as a single cell. General laboratory procedures for reducing ribonuclease (RNase) activity, both in reagents and in the laboratory environment, are required for successful downstream RNA isolation and quantitation. Quality RNA can be extracted from sections made from flash-frozen and paraffin-embedded tissue. The standard histological stains such as hematoxylin and eosin (H&E), or toluidine blue, can provide visualization of the cells of interest. Following LMD, validation of RNA integrity should precede downstream analysis.
Subject(s)
Lasers , Microdissection/methods , RNA/analysis , Tissue and Organ Harvesting/methods , Humans , RNA/antagonists & inhibitors , Staining and Labeling/methodsABSTRACT
Detection of proliferating cells based on bromodeoxyuridine (BrdU) incorporation and determination of phenotype by immunofluorescence labeling are standard approaches for studying stem and progenitor cell populations in developing and adult tissue as well as in histopathology studies. We describe incorporation of different halogenated thymidine analogs for temporal discrimination of cell cycle in the rat. With equimolar delivery, these analogs are suitable for quantitative histological studies including assessment of the regulation of proliferation, clonal analysis and simultaneous profiling of cell phenotype relative to proliferative history.