Stuttgart (ddp). Scientists from the Fraunhofer Institute have developed a human art liver with functioning circulatory system for Interfacial and biological engineering (IGB) in Stuttgart. The so-called 3-D-vaskularisierte model made possible for the first time meaningful studies of new drugs on human liver tissue, shares with the ITUC. The new development could possibly replace animal testing. The test system is similar to the human liver. The artery takes nutrients, oxygen, and the active substances to be analysed in the artificial liver. There, liver cells break down substances. The metabolites are transported through the vein. To ensure the blood supply to the liver of art, a piece of pig small intestine that has an artery for the blood supply and a vein for the derivation of served researchers. You removed the animal cells, so that in addition to the proteins of the connective tissue layer remained only the tubes of the vascular system, which is applied like a fan up in fine capillaries. The scientists – dressed similar to of this network at the living model – from the inside with human endothelial cells. So soon in the vascular system of artificial blood circulates can grow on the matrix cells of the various institutions. Because the fabric has an own bloodstream, can be obtained for weeks in the life there in the bioreactor. A computer controls the arterial pressure, temperature and flow rate. The test system according to the, helps to identify at an early stage toxic or not effective substances in drug development and to save costs. Pharmaceutical companies invest much money in the development of new drugs. Here, researchers set mostly on animal testing. But the body of a mouse or a pig reacts differently than the human body. They also artificial or immortal (immortalisierten) cell cultures of human cells provide only limited meaningful results.