Hemoglobin also carries the important regulatory molecule nitric oxide bound to a globin protein thiol group, releasing it at the same time as oxygen. Haemoglobin is also found outside red blood cells and their progenitor lines. Other cells that contain haemoglobin include the A9 dopaminergic neurons in the substantia nigra, macrophages, alveolar cells, lungs, retinal pigment epithelium, hepatocytes, mesangial cells in the kidney, endometrial cells, cervical cells and vaginal epithelial cells. In these tissues, haemoglobin has a non-oxygen-carrying function as an antioxidant and a regulator of iron metabolism. Haemoglobin and haemoglobin-like molecules are also found in many invertebrates, fungi, and plants.
Genetically engineered blood Genetically engineered blood Genetically engineered blood is blood that has been modified for therapeutic or other purposes. Genetically modifying red blood stem cells allows them to produce specific therapeutic proteins on the surface or inside the cell. The stem cells are taken from mammalian bone marrow and are modified in culture. Before they become mature, mammalian red blood cells eject their genetic material. Culturing cells that produce a new protein of interest requires only a few weeks. Using the sortagging protein labeling technique, the researchers used the bacterial enzyme sortase A to establish a strong chemical bond between the surface