The erythrocyte contributes to the immune system in several ways. It sequesters interferons, interleukins or chemokines and by binding nucleic acid. It binds virus and bacteria and may deliver bacteria to macrophages for phagocytosis. It may also kill bacteria directly with oxygen. For proper function of the erythrocyte, homeostasis of reactive oxygen species, selenium, metal ions and trace elements is important. Erythrocytes display morphological and metabolic changes in diseases like sepsis, and in several genetic diseases. Patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), giving rise to the coronavirus disease 2019 (Covid-19), show many erythrocyte changes as compared to healthy controls. The erythrocyte responds to hemolysins by purinergic signaling leading to hemolysis or phosphatidylserine exposure on the plasma membrane. Phosphatidylserine marks erythrocytes for clearance by spleen macrophages. Regulated erythrocyte cell death, also called eryptosis, can be induced by oxidative stress, pathogen infection, and certain diseases like sepsis. Erythrocytes may, in the future, contribute more to diagnosis based on research and diagnostic technological development.
Part of the book: Erythrocyte
Evolution has created a hierarchy of systems for information and energy using different cells according to messages generated from DNA, RNA, and other sources. Erythrocytes are formed in high speed at about 2 × 106/s to balance dying or not working erythrocytes to maintain optimal energy and information transfer. Important information is handled by nucleotides and distribution of metal ions and phosphates when starting synthesis process. Handling of these processes needs kinases known to be magnesium-dependent. Oxygen delivered by erythrocytes is used by other cells to synthesize ATP and to increase reaction capacity. Complex signals to bone marrow balance erythroblasts before developing into reticulocytes and erythrocytes. We discuss some aspects of erythrocyte communication with other cells of the body with special focus on magnesium and selenium in this process.
Part of the book: The Erythrocyte