Donor Myocardial Infarction Impairs the Therapeutic Potential of Bone Marrow Cells by an Interleukin-1-Mediated Inflammatory Response

Delivery of bone marrow cells (BMCs) to the heart has substantially improved cardiac function in most rodent models of myocardial infarction (MI), but clinical trials of BMC therapy have led to only modest improvements. Rodent models typically involve intra-myocardial injection of BMCs from distinct donor individuals that are healthy, unlike autologous BMCs used for clinical trials that are from post-MI individuals. Using BMCs from post-MI donor mice, we discovered that recent MI impaired BMC therapeutic efficacy. MI led to myocardial inflammation and an increased inflammatory state in the bone marrow, changing the BMC composition and reducing their efficacy. Injection of a general anti-inflammatory drug or a specific interleukin-1 inhibitor to post-MI donor mice prevented this impairment. Our findings offer an explanation of why human trials have not matched the success of rodent experiments, and suggest potential strategies to improve the success of clinical autologous BMC therapy.