Received: 22 January 2019 | Revised: 4 April 2019 | Accepted: 11 April 2019 DOI: 10.1002/jcp.28738 REVIEW ARTICLE Toll‐like receptors in the functional orientation of cardiac progenitor cells Mohammadreza Yousefi 1,2 * | Mina Mamipour 1,2 * | Sadiye E. Sokullu 3 | Shahrooz Ghaderi 4 | Hasan Amini 1,5 | Reza Rahbarghazi 6,7 1 Stem Cell Research Center, Tabriz University of Medical Sciences, Tabriz, Iran 2 Research Center for Translational Medicine, Koç University, Istanbul, Turkey 3 Engineering Sciences, Bioengineering Department, Faculty of Engineering and Architecture, Izmir Katip Celebi University, Izmir, Turkey 4 Department of System Physiology, Ruhr University, Bochum, Germany 5 Department of General and Vascular Surgery, Tabriz University of Medical Sciences, Tabriz, Iran 6 Tuberculosis and Lung Disease Research Center, Tabriz University of Medical Sciences, Tabriz, Iran 7 Department of Applied Cell Sciences, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran Correspondence Dr. Reza Rahbarghazi, Stem Cell Research Center, Tabriz University of Medical Sciences, Imam Reza St., Golgasht St., Tabriz 5166614756, Iran. Email: rezarahbardvm@gmail.com, rahbarghazir@tbzmed.ac.ir Funding information Tuberculosis and Lung Disease Research Center, Tabriz University of Medical Sciences, Grant/Award Number: IR.TBZMED.VCR.REC.1397.485; Tabriz University of Medical Sciences, Grant/Award Number: IR.TBZMED.VCR.REC.1397.485 Abstract Cardiac progenitor cells (CPCs) have the potential to differentiate into several cell lineages with the ability to restore in cardiac tissue. Multipotency and self‐renewal activity are the crucial characteristics of CPCs. Also, CPCs have promising therapeutic roles in cardiac diseases such as valvular disease, thrombosis, athero- sclerosis, congestive heart failure, and cardiac remodeling. Toll‐like receptors (TLRs), as the main part of the innate immunity, have a key role in the development and differentiation of immune cells. Some reports are found regarding the effect of TLRs in the maturation of stem cells. This article tried to find the potential role of TLRs in the dynamics of CPCs. By showing possible crosstalk between the TLR signaling pathways and CPCs dynamics, we could achieve a better conception related to TLRs in the regeneration of cardiac tissue. KEYWORDS cardiac progenitor cells, cell dynamics, functional behavior, toll‐like receptor 1 | INTRODUCTION The survival of an organism depends on the activity of the immune system by engaging two defensive strategies termed as innate and adaptive immune systems. Each of these systems plays a critical role in the lifespan. The innate immune system recognizes and reacts to the microbial agents through toll‐like receptors (TLRs) as they enter the bloodstream (Takeda, Kaisho, & Akira, 2003). Up to now, 10 mammalian TLRs have been discovered and identified. Each TLR binds to a specific ligand and interacts with several adapter molecules. The members of TLR family exist on different cell lineages with the ability to promote different signaling pathways that lead to nuclear activation, resulting in producing various cytokines, chemo- kines, and several genes involved in normal cell maturation procedure (Liotta et al., 2008). Numerous signaling pathways activated by TLRs are found in correlation with cardiovascular J Cell Physiol. 2019;1–13. wileyonlinelibrary.com/journal/jcp © 2019 Wiley Periodicals, Inc. | 1 *Mohammadreza Yousefi and Mina Mamipour are considered as the co‐first author.