Human Autoantigen Atlas: Searching for the Hallmarks of Autoantigens

Understanding autoimmunity to endogenous proteins is
crucial in
diagnosing and treating autoimmune diseases. In this work, we developed
a user-friendly AAgAtlas portal (http://biokb.ncpsb.org.cn/aagatlas_portal/index.php#), which can be used to search for 8045 non-redundant autoantigens
(AAgs) and 47 post-translationally modified AAgs against
1073 human diseases that are prioritized by a credential score developed
by multisource evidence. Using AAgAtlas, the immunogenic properties
of human AAgs was systematically elucidated according to their genetic,
biophysical, cytological, expression profile, and evolutionary characteristics.
The results indicated that human AAgs are evolutionally conserved
in protein sequence and enriched in three hydrophilic and polar amino
acid residues (K, D, and E) that are located at the protein surface.
AAgs are enriched in proteins that are involved in nucleic acid binding,
transferase, and the cytoskeleton. Genome, transcriptome, and proteome
analyses further indicated that AAb production is associated with
gene variance and abnormal protein expression related to the pathological
activities of different tumors. Collectively, our data outlines the
hallmarks of human AAgs that facilitate the understanding of humoral
autoimmunity and the identification of biomarkers of human diseases.