Authors declare no conflicts of interest.

Here we provide a SOP to outline the correct procedures to dual stain FFPE human tissue for, 1) pathological TDP-43 protein, along with 2) any other protein of interest, with the aim of visualising protein of interest histology in the context of TDP-43 pathology.

This protocol can be implemented for dual staining of any rabbit or mouse primary detection antibody (using the Novolink Polymer Detection System), with our TDP-43 RNA aptamer (biotinylated) as published in Acta Neuropathologica herehttp://link.springer.com/article/10.1007/s00401-024-02705-11 in Spence and Waldron et al l., 2024.

The resulting dual stain will show brown chromogen (detecting the target of the primary antibody) with red chromogen (detecting TDP-43 pathology with our TDP-43 RNA aptamer.

Reference for citations of this method

Clinicopathological analysis of NEK1 variants in amyotrophic lateral sclerosis. NEK1 variants in amyotrophic lateral sclerosis.

Olivia M. Rifai, Fergal M. Waldron, Danah Sleibi, Judi O’Shaughnessy, Danielle J. Leighton*, Jenna M. Gregory*^‡ (2024). Brain Pathology doi: 10.1111/bpa.13287  (in press at the time of publication of this SOP) *equal contributions, ^‡corresponding author.

Antibody and TDP-43 RNA aptamer dual staining to detect patterns of  co-pathology in FFPE-preserved human tissue, as described in Rifai et al., 2024 (Brain Pathology): An SOP and tick-sheet .

Fergal M. Waldron, Olivia M. Rifai, Jenna M. Gregory^‡, (2024). Protocols.io 2024; doi: tbc

^‡corresponding author

IHC_SOP_Double Stain_Antibody & TDP-43 RNA Aptamer_v1.0_03Jul24.pdf IHC_TS_Double Stain_Antibody & TDP-43 RNA Aptamer_v1.0_03Jul24.pdf