#4. What is the cause of Systemic lupus erythematosus?

Systemic lupus erythematosus is the prototype of a multi-organ autoimmune disease. Patients usually carry multiple autoantibodies, especially anti-nuclear antibodies. These antibodies probably mediate the pathological processes. Other genes probably play a part as well. The autoimmunity is predisposed by certain HLA class II alleles. No commonly accepted pathogen has been identified.

Figure 4. Antinuclear anibody demonstrated by immunofluorescence.