Immunization of mice with proteins reacted with malonic dialdehyde (MDA): comparison between autologous and heterologous modified proteins.

In previous experiments, rabbits were injected with heterologous proteins reacted with MDA, and produced antibodies cross-reacting with other MDA-modified proteins (MPr), but not with the corresponding native ones (Pr). It was concluded that these antibodies (AbAIP) recognized epitopes including 1-amino-3-imino-propene (AIP) bridges resulting from reactions of MDA with primary amino groups of proteins. In the present work, mice were injected with autologous MDA-modified albumin (MAI) or with heterologous MPr. Mice immunized with MAI developed an immune response leading to an increased production of AbAIP, which clearly indicates that such a response may occur even with an autologous MPr.