In-house Manual Construction of High-Density and High-Quality Tissue Microarrays by Using Homemade Recipient Agarose-Paraffin Blocks

BACKGROUND Self-made tissue punches can be effectively used to punch holes in blank recipient paraffin blocks and extract tissue cores from the donor paraffin blocks for the low-cost construction of tissue microarrays (TMAs). However, variable degrees of section distortion and loss of the tissue cores can occurs during cutting of the TMAs, posing technical problems for in-house manual construction of high-density TMAs. We aimed to update the method for in-house manual TMA construction to improve the quality of high-density TMAs. METHODS Blocks of agarose gel were subjected to the standard tissue processing and embedding procedure to prepare recipient agarose-paraffin blocks. The self-made tissue punches and recipient agarose-paraffin blocks were used to construct TMAs, which were completely melted and re-embedded in paraffin to make finished TMA blocks. RESULTS The donor tissue cores were completely integrated into the surrounding paraffin of the recipient blocks. This method enabled us to construct high-density TMAs with significantly less section distortion or loss of tissue cores during microtomy. CONCLUSIONS Simple and inexpensive construction of high-density and high-quality TMAs can be warranted by using paraffinized agarose gels as recipient blocks.