Autofluorescence Patterns in Short-Term Cultures of Normal Cervical Tissue

Abstract

Fluorescence spectroscopy has potential to improve cervical precancer detection. The relationship between tissue biochemistry and fluorescence is poorly understood. The goal of this study was to characterize normal cervical autofluorescence, using fresh tissue short-term tissue cultures and epithelial cell suspensions. Transverse, short-term tissue cultures were prepared from 31 cervical biopsies; autofluorescence images were obtained at 380 and 460 nm excitation. Fluorescence excitation-emission matrices were measured from normal, precancerous and cancerous cervical cell suspensions. Observed fluorescence patterns contrast those reported for frozen-thawed tissue, and were placed into groups with (1) bright epithelial and weak stromal fluorescence; (2) similar epithelial and stromal fluorescence; and (3) weak epithelial and bright stromal fluorescence. The average ages of women in the groups were 30.9, 38.0 and 49.2 years. Epithelial fluorescence intensity was similar in Groups 1 and 2, but weaker in Group 3. Stromal intensity was similar in Groups 2 and 3, but weaker in Group 1. The ratio of epithelial to stromal fluorescence intensity was significantly different for all groups. EEMs of cell suspensions showed peaks consistent with tryptophan, reduced form of nicotinamide adenine dinucleotide (phosphate) and flavin adenine dinucleotide. Short-term tissue cultures represent a novel, biologically appropriate model to understand cervical autofluorescence. Our results suggest a biological basis for the increased fluorescence seen in older, postmenopausal women.

Optimal methods for fluorescence and diffuse reflectance measurements of tissue biopsy samples

“…The excitation±emission wavelength pairs of the tissue¯uorescence peaks were located at 300±345, 320±390, 340±460, and 460±520 nm, which are thought to correspond to tryptophan, collagen, NADH, and FAD, respectively [14]. The¯uorescence emission spectra of the frozen and thawed tissues at these excitation wavelengths are 30±50% of the corresponding in vivo state.…”

<title>Fluorescence and reflectance spectra of freshly excised cervical tissue</title>

“…It has been shown that these whitening changes are valuable in reflectance measurements (9) and fluorescence measurements (10) in differentiation of neoplastic and normal cervical tissue. Data collected in this study from non-neoplastic cervical tissue reveal changes after the application of acetic acid (Figs.…”

Fluorescence spectroscopy for in vivo characterization of ovarian tissue

“…Differences at 330 nm excitation can be attributed to changes in the¯uorescence of structural proteins, NADH, and reabsorption due to hemoglobin. The source of these changes can be explored using¯uorescence microscopy of short-term tissue cultures [14]. This pilot study suggests that such microscopy of normal and neoplastic ovarian tissue should be carried out at 330, 375, and 415 nm excitation.…”