Since the beginning of the autoimmunity field, autoantibodies have been the tool used by clinical laboratories to diagnose and monitor autoimmunity. Prevalence of ANA in the general population by age and gender (Guo YP et al Curr Ther Res, 2014).Īutoantibodies are an excellent biomarker for autoimmunity The appearance of these autoimmune events secondary to the use of cancer immunotherapy strongly suggests that autoreactive T cells and autoreactive B cells (i.e., autoantibodies) do exist in healthy individuals, but are kept under control by regulatory mechanisms. This broad activation of effector T cells, however, unleashes in a relatively short time a variety of immune-related side effects that resemble the autoimmune diseases occurring in the absence of cancer immunotherapy. Cancer patients who are treated with inhibitors of immune checkpoints (such as CTLA-4 and PD-1) develop a broad activation of their effector T cells, which is the basis for eliminating the tumor cells. Similar reasoning applies to autoreactive T cells, although in the clinical laboratory it is much more complicated to test for T cells than for autoantibodies.Īn additional proof that autoantibodies and autoreactive T cells can be present in individuals who do not have clinical evidence of autoimmune disease comes from the new types of cancer treatment based on immunotherapy.
Thus, it is not surprising that if we were to test the serum broadly enough, we would find some autoantibodies in most “healthy” individuals. If we use autoantibodies as an indicator for autoimmunity, we find there are many, many types of autoantibodies, directed against many different self-antigens.