Glomerular targets for autoantibodies in lupus nephritis--an apoptotic origin

Systemic lupus erythematosus (SLE) is an autoimmune syndrome where different organs may individually or simultaneously be affected. Whether SLE is one disease entity or represents a variety of intrinsically unrelated organ manifestations is unknown. Variability of clinical presentations of SLE argues against the former. This does not, however, exclude that certain organ manifestations may be pathogenetically linked. It is believed that in situ binding of anti-dsDNA antibodies by nucleosomes is involved in organ manifestations in SLE. This review will focus on nature and origin of target structures for anti-dsDNA and antinucleosome antibodies in glomerular capillary and mesangial matrix membranes. We will particularly discuss the potential role of apoptosis and release of apoptotic chromatin in terms of their putative impact in SLE.