Solid phase cytometry allows rapid in situ quantification of human papilloma virus infection in biopsy material

Solid phase cytometry would be an asset for many histological and cytological studies. Current microscope-based cytometers and image analysis systems are too slow to analyze specimens several millimeters wide. We have recently shown that a rapid wide area laser scanning device that operates on solid supports has a linear response. We assess it here for solid phase cytometry. Each cell detected by the cytometer can be automatically positioned for visual observation in the field of an epifluorescence microscope (conventional or confocal) in which the stage is driven by the instrument's computer. We were able to detect and map human papillomavirus-infected cells labeled by fluorescent in situ hybridization in cervical condyloma biopsies. We could quantify the fluorescence emitted by these cells and show differences of up to 35-fold in fluorescence intensity between individual cells. These differences in intensity might reflect differences in viral copy number. The potential of the system to provide fast, reliable and reproducible analyses of solid tissue samples is discussed.