Loss of anti-AT1R reactivity in ELISA post-adsorption - False reactivity or interference in the assay?

Autoantibodies to Angiotensin II type 1 receptor (AT1R) are associated with detrimental outcomes in organ transplants. However, reports showed that adsorption with latex beads reduced positive anti-AT1R antibodies, suggesting possible false reactivity. To investigate this conundrum, we studied 11 samples positive for AT1R antibodies with an ELISA kit before and after adsorption.