Over expression of a soluble FKN (sFKN; predicted to be the ADAM10/17 cleavage product, Fig. 1) via AAV in the rTg4510 mouse model of tauopathy reduced both soluble and insoluble phospho-tau pathology, ameliorated neuron loss, and reduced microglial activation. This evidence concerns the gene CX3CL1 and tauopathy.