Atherosclerosis is the main underlying pathology of cardiovascular disease, the largest single cause of death in industrialized countries, and current treatment is still largely insufficient. In recent years it has become evident that immune responses contribute to atherosclerosis. Therefore, during my PhD studies I focused on developing a therapy to induce and expand anti-inflammatory immune cells to reduce ongoing immune responses and atherosclerosis. I used the approach of cellular therapy and examined the effect of several different anti-inflammatory immune cells. For example, I made use of mesenchymal stem cells, which have previously been used to improve cardiac repair after myocardial infarction and were found to have anti-inflammatory properties. Additionally, I used drugs, e.g. inhibitors of protein degradation, and biologics, e.g. components of heat-killed bacteria, to directly increase the amount of anti-inflammatory immune cells. An interesting side-effect of some treatments was that they additionally reduced cholesterol levels. In summary, I have shown in pre-clinical models that immune cell-based therapies are promising for the treatment of atherosclerosis. As atherosclerosis is determined by both high cholesterol levels and inflammation reducing immune responses will greatly contribute to a better treatment of cardiovascular patients in the (near) future.Dutch Heart Foundation Peprotech Greiner Bio-One BD Biosciences Leiden UniversityUBL - phd migration 201