Autofluorescence spectroscopy of malpighian epithelial cells,as a new tool for analysis of cervical cancer precursors

A spectroscopic analysis of autofluorescence was investigated within the cell cytoplasm from cervical malpighian epithelia prepared on Thin-Prep smears. Autofluorescence emission spectra from 22 cervix were analyzed by microspectrofluorometry under a 363 nm laser excitation. Among the analyzed cervix, 6 were in normal limits, 6 in inflammatory limits, 5 were evocative of Low-Grade Squamous Intraepithelial Lesions (LGSILs) and 5 were evocative of High-Grade Squamous Intraepithelial Lesions (HGSILs). Cytoplasmic emission intensities at 450 nm of cells from inflammatory, LGSIL and HGSIL cervix were equivalent and were 3-fold higher than from normal cervix. All smears presented a two-fold lower autofluorescence emission in the cytoplasm than in the nucleus. The spectral profile analysis allows the discrimination of cells from inflammatory, LGSIL and HGSIL cervix. The 525/425 nm emission ratios were 0.75+/-0.1, 0.96+/-0.04 and 1.2+/-0.1 for inflammatory, LGSIL and HGSIL, respectively. We suggest that smears of normal, inflammatory, LGSIL and HGSIL cervix could be discriminated by the analysis of the 450 nm emission intensity and 525/425 nm emission ratios from cells of malpighian epithelia.