Serological Antibodies Against Membrane Antigens As Potential Biomarkers of Immune Disorders

Immune disorders, characterized by dysregulation at cellular and inflammatory levels, result from a complex interplay of genetics and environmental factors that lead to an abnormal immune response against autoantigens, triggering tissue damage. Recent research highlights reactive antibodies as key players in autoimmune diseases and graft rejection, but the complexity of their determination limits their use in clinic. Hence, we studied the specific binding profile of serological antibodies against a panel of cellular membranes in order to determine whether this antigenic panel could be used to diagnose specific immune disorders in humans. For this purpose, cell membrane microarrays of spleen, liver, and kidney tissues of monkey, rat, and human were developed, and human sera were analyzed, including healthy controls, patients with autoimmune disorders, and kidney transplant patients. A significant increase in antibody reactivity against specific monkey kidney and spleen membranes was observed in the serum of patients with lupus nephritis, while kidney transplant patients showed a significant enhancement against human tissues and Human embryonic kidney 293 cells. These results show the potential importance for clinical and basic research purposes of studying the presence of specific IgG against membrane antigens in the serum of patients as potential biomarkers of immune disorders.