Stryker doesn't budge an inch. "These are not people. They're mutants. If we don't defend ourselves against them, they will do away with us first. Personally, I'm not going down without striking back first."
At the Doctor's no, he simply shrugs and calls for a medical technician who comes in to take some of the Doctor's blood. "If that's how you feel about it..." Once he gets the blood, Stryker can formulate a dose for the Doctor.
Till then, the two of them are left alone in the cell again. Kurt only lets him go once the door shuts again, going back to sit in his corner.