Application of the tissue transfer technique in veterinary cytopathology

Abstract

Background: Limited availability of diagnostic cytopathologic material may preclude additional diagnostic techniques. Tissue transfer allows for preparation of additional slides from a single original slide. Information pertaining to the application of the tissue transfer technique in veterinary cytopathology is lacking.

Objectives: The objectives were to evaluate the application of the tissue transfer technique on Quick Dip-stained veterinary cytologic smears and to assess if a selection of histochemical and immunocytochemical stains, and PCR analyses could be performed on transferred material.

Methods: Archived Quick Dip-stained canine lymph node aspirate smears from previously diagnosed lymphoma cases were utilized to validate and optimize the tissue transfer technique. In this technique, diagnostic material is lifted from the original stained slide, is divided and transferred to multiple new slides. Histochemical stains such as Gram, periodic acid Schiff, Congo red, and Ziehl-Neelson, immunohistochemistry for CD3 and PAX5, and PCR for cryptococcal and mycobacterial organisms were selectively performed on transferred material.

Results: The tissue transfer technique was simple, and transferred Quick Dip-stained material retained cellular morphology. Histochemical and immunohistochemical stains, and PCR analysis yielded reliable results when performed on the additional smears produced by this technique.

Conclusions: The tissue transfer technique was simple and easy to perform on previously Quick Dip-stained cytology smears. Cellular detail was preserved and multiple additional ancillary diagnostic techniques were facilitated, such as histochemical and immunohistochemical stains, and PCR analysis.

Keywords: Archiving; PCR; cell lifting; histochemical stains; immunocytochemistry.