If antibody binds to normal tissues it can cause damage to the body or create other disease symptoms. Rheumatoid arthritis is a good example of an autoimmune disease. Antibodies that react with body tissues are felt to contribute to joint swelling and pain.
In eukaryotic cells the pyruvate decarboxylation occurs inside the mitochondria, after transport of the substrate, pyruvate, from the cytosol. The transport of pyruvate into the mitochondria is via a transport protein and is active, consuming energy. Passive diffusion of pyruvate into the mitochondria is impossible because it is a polar molecule. On entry to the mitochondria the pyruvate decarboxylation occurs, producing acetyl CoA.
Electron Transport in the Energy Cycle of the Cell. The eukaryotic cell's most efficient path for production of vital ATP is the aerobic respiration that takes place in the mitochondria. After glycolysis, the pyruvate product is taken into the mitochondia and is further oxidized in the TCA cycle. This cycle deposits energy in the reduced coenzymes which transfer that energy through what is called the electron transport chain.