Red blood cells (RBCs) have been studied as models for infectious diseases, various symptoms of anemia, hemolysis, and erythrocyte aging. Although do not directly affect RBCs, other diseases may cause RBC physiological alterations that could be advanced for diagnostic aim or to convince better understanding of a certain pathological pattern. In this study, comparative RBC proteomics between healthy and abnormal conditions involve to promote aging related‐biomarker discovery. Peroxiredoxin II (Prdx II; a typical 2‐Cys Prdx) has been originally isolated from erythrocytes, and its structure and peroxidase activity have been adequately studied. Mice absent to Prdx II proteins had heinz bodies in their peripheral blood, and morphologically aged cells were detected in the dense RBC fractions, which contained markedly higher levels of reactive oxygen species (ROS). In addition, a labeling experiment with the thiol‐modifying reagent biotinylated iodoacetamide (BIAM) in Prdx II‒/‒ mice revealed that a variety of RBC proteins were highly oxidized. To identify oxidation‐sensitive proteins in Prdx II‒/‒ mice, we performed RBC comparative proteome analysis by nano‐UPLC‐MSE shotgun proteomics with relative protein quantitative analysis. We found oxidation‐sensitive 18 membrane and 41 cytosol proteins from 32 and 85 peptides containing cysteine oxidation, and analyzed comparative expression pattern in healthy RBCs of Prdx II+/+ mice (W1), healthy RBCs of Prdx II‒/‒ mice (K1), and abnormal RBCs of Prdx II‒/‒ mice (K2). These proteins belonged to cellular functions related with RBC lifespan maintain, such as cytoskeleton, stress‐induced proteins, amino acid/nucleic acid metabolic enzymes, signal transduction, and molecular transporters. Furthermore, protein networks among identified oxidation sensitive proteins were analyzed to associate with aging consequence. Consequently, we expected that RBC proteome may provide clues to understand redox‐imbalanced diseases.

• Tae‐Hoon Lee(Department of Oral Biochemistry, Dental Science Research Institute, The 2nd Stage of Brain Korea 21 for Dental School, Chonnam National University)
• Hee‐Young Yang(Department of Oral Biochemistry, Dental Science Research Institute, The 2nd Stage of Brain Korea 21 for Dental School, Chonnam National University)
• Hoon‐In Choi(Department of Oral Biochemistry, Dental Science Research Institute, The 2nd Stage of Brain Korea 21 for Dental School, Chonnam National University)
• Gia‐Buu Tran(Department of Oral Biochemistry, Dental Science Research Institute, The 2nd Stage of Brain Korea 21 for Dental School, Chonnam National University)
• Ung Yang(Department of Oral Biochemistry, Dental Science Research Institute, The 2nd Stage of Brain Korea 21 for Dental School, Chonnam National University)