Cellular DNA content in normal human thyroid: a flow cytometric study based on frozen biopsy material

Area of Science:

• Biomedical Science
• Cell Biology
• Pathology

Background:

• Accurate DNA content measurement in thyroid tissue is crucial for diagnosis.
• Conventional methods for preparing frozen biopsy samples can impact measurement accuracy.
• Flow cytometry offers a sensitive method for cellular DNA analysis.

Purpose of the Study:

• To develop and validate a method for preparing conventionally frozen thyroid biopsy material for DNA flow cytometry.
• To establish the reliability and accuracy of the proposed preparation technique.
• To determine the threshold for significant deviations from diploid DNA content in thyroid cells.

Main Methods:

• Preparation of frozen thyroid biopsy samples using Histocon preservative solution before freezing.
• Flow cytometric measurement of DNA content in cell suspensions.
• Calibration of fluorescence measurements using fluorescent microspheres.
• Analysis of 24 normal thyroid tissue biopsies from 20 patients.

Main Results:

• Immersion in Histocon preservative solution prior to freezing yielded superior results compared to dry freezing.
• All analyzed samples exhibited a consistent modal DNA value, confirming diploidy.
• A deviation exceeding 13-14% from diploid DNA content was identified as significant using this technique.

Conclusions:

• The presented method provides an accurate and reliable approach for preparing frozen thyroid biopsies for DNA flow cytometry.
• The technique allows for the precise determination of DNA content and identification of aneuploidy in thyroid cells.
• This method enhances diagnostic capabilities for thyroid tissue analysis.