Isolation of endogenous cytosolic DNA from cultured cells.

DNA damage caused by genetic instability or extrinsic treatment can induce DNA leakage from the nucleus or mitochondria into the cytosol and activate innate and adaptive immunity. To enable characterization of these endogenous cytosolic DNAs and the mechanisms that produce them, we developed an approach for isolation of cytosolic DNA with no detectable mitochondrial contamination. Here we describe cytosolic compartment separation followed by DNA purification from colorectal cancer cells and illustrate how this may be expanded to other cell types.