Characterization of exfoliated cells and tissues from human endocervix and ectocervix by FTIR and ATR/FTIR Spectroscopy

Abstract

AbstractThe transmission infrared spectra of exfoliated endocervical mucin‐producing columnar epithelial cells and the attenuated total reflectance (ATR) infrared spectra of the single‐columnar cell layer on the endocervical tissues have been measured and compared with the corresponding infrared spectra of the ectocervical squamous cells and squamous epithelium. The infrared spectra of the exfoliated cervical cells obtained from the present work are comparable with those directly measured from the epithelia on the cervical tissues by ATR technique. The transmission infrared spectra of endocervical columnar epithelial tissue containing some components of the underlying connective tissue have also been measured and compared with the ATR/FTIR (Fourier‐transform infrared) spectra of the endocervical columnar epithelial tissue. The effects of the contaminated connective tissue on the infrared spectra of the endocervical columnar epithelial tissue have demonstrated that ATR/FTIR is a more desirable method than the transmission method to obtain meaningful and good‐quality infrared spectra of tissue samples, especially samples consisting of thin layers of different types of tissues. Substantial differences in the infrared spectra between the columnar cells and squamous cells on the endocervical and ectocervical tissues, respectively, were evident. The strong glycogen bands in the infrared spectrum of the ectocervical squamous cells are absent in the spectrum of the endocervical columnar cells. This spectral change is similar to that observed in malignant squamous cells. Therefore, if the decrease in the intensity of the glycogen bands is used as the only criterion for the determination of cellular abnormalities in the cervix, the presence of a large number of normal endocervical columnar cells in the cervical specimen would lead to a false result. Consequently, in addition to the glycogen bands, other features in the infrared spectra should be considered for the evaluation of abnormalities in exfoliated cervical epithelial cells. In order to identify the spectral features that are unique to endocervical columnar cells, the infrared spectra of an aqueous solution of glycogen, the mucus from the endocervix, and the connective tissues from both the endocervix and the ectocervix have also been measured and analyzed. © 1995 John Wiley & Sons, Inc.