Five anti-TDP scFvs with high selectivity for FTD sera over the controls (FTD-TDP1, FTD-TDP2, FTD-TDP4 and FTD-TDP5) and a commercial antibody against TDP-43 were separately co-incubated with the cells at a concentration of 1 μg/mL to block TDP variants from interacting with the cells. Here, TDP1 is linked to frontotemporal dementia.