A 46-year-old woman comes to the physician for a 1-week history of progressively worsening skin lesions and a painful intra-oral lesion. Physical examination shows scattered intact and ruptured bullae on the trunk. Palpation of one of the bullae with lateral friction causes it to rupture. Antibodies directed against which of the following is most likely responsible for this patient’s condition?
A
B
C
D
E
