Apoptosis and cell penetration by autoantibody may represent linked processes

An hypothesis is presented in which the natural physiologic process of apoptosis may sometimes be linked to cell penetration by autoantibody. Apoptotic blebs as residuals of the programmed cell death process have recently been demonstrated to contain clusters of disparate autoantigens which have previously been implicated in the generation of autoimmune reactions. In parallel, there now exists a mounting body of evidence that certain autoantibody molecules are capable of living cell penetration and even nuclear membrane ingress. We suggest that these two processes, apoptosis and cell penetration by autoantibody, may be associated with one another in certain circumstances.