A novel immunohistochemistry slide adhesive 3-(trimethoxysilyl) propyl methacrylate (tpm) for bluetongue virus serotype-1 antigen detection in ovine foetal tissues

The present study describes the use of 3-(trimethoxysilyl) propyl methacrylate (TPM) as a glass slide adhesive for better tissue adherence in immunohistochemistry. TPM is an alkoxysilane, dissolved in acidified water (pH 3.5) with glacial acetic acid. TPM formed a gel cast on the glass slide surface, which enhanced the net positive charge of the slide. Tissues with net negative charge adhered with gel cast adhesive on the slide surface with covalent bonding. Practically, foetal tissues have less tissue adherence capacity due to less net negative charge. Foetal brain, pancreas, lymph node and umbilical cord of sheep were included in the study. Foetal tissues were collected and fixed in Bouin’s fixative and processed as per standard paraffin embedding technique. Immunohistochemistry was performed on foetal tissues and umbilical cord using three different glass slide adhesive such as poly-L-lysin (PLL), aminopropyl triethoxy silane (APES) and TPM under different antigen retrieval system. TPM significantly enhanced the foetal tissue adherence, when compared with commercially available adhesives such as PLL and APES. In the present study, foetal tissues adhered with TPM coating well tolerated the harsh proteinase K antigen retrieval treatment. Comparatively, TPM coated slides revealed mild to zero tissue loss and less to no background staining. In addition, TPM was cost effective as many commercially available slide adhesives were either costlier or needed accessory chemicals for coating which in turn added the cost per slide. The present study showed that TPM was cost-effective, less hazardous, less time consuming, easy-to-use adhesive for manual preparation of coating slides when compared to other protein adhesive systems. The present experiment also emphasized that tissues with less adherence capacity could be coated with TPM adhesive for best IHC results.