How to obtain good morphology and antigen detection in the same tissue section?

Area of Science:

• Histopathology
• Immunohistochemistry
• Biopsy Sample Processing

Background:

• Paraffin embedding is standard for biopsy samples, offering good morphology but often hindering antigen detection.
• Cryosections preserve antigens well for techniques like immunofluorescence but typically lack detailed morphology.
• A method combining good morphology and antigen preservation is needed for effective pathological evaluation and research.

Purpose of the Study:

• To evaluate novel cryosectioning methods for improved antigen preservation and tissue morphology.
• To compare these methods against routine formaldehyde fixation and paraffin embedding.
• To assess the clinical relevance of the optimal method for human biopsy samples.

Main Methods:

• Tested three fixation and freezing methodologies, including sucrose impregnation prior to freezing.
• Used rat urinary bladder and trachea epithelium as a model system.
• Performed haematoxylin and eosin staining and immunofluorescence for ZO-1 and cytokeratin 7 on all samples.

Main Results:

• The sucrose impregnation prior to freezing method yielded the best balance of morphology and immunofluorescence.
• This method proved quicker than standard paraffin embedding.
• Human neoplastic biopsy samples showed good morphology and immunofluorescence using this technique.

Conclusions:

• Sucrose impregnation prior to freezing offers a superior compromise between morphology and antigen preservation for cryosections.
• This method is faster than paraffin embedding and clinically relevant for human samples.
• The proposed cryosectioning technique warrants further use in clinical and veterinary pathology.