Role of pattern recognition receptors in the therapeutic effect of immunobiotics and immunogenics

HARUKI KITAZAWA; JULIO VILLENA

Mar del Plata, Argentina

Congreso; LVII REUNION CIENTIFICA ANUAL Sociedad Argentina de Investigacion Clínica (SAIC) - LX REUNION ANUAL Sociedad Argentina de Inmunologia (SAI); 2012

Sociedad Argentina de Inmunología

Recent interest has focused on the importance of microbiota and intestinal mucosal immune system for the host defense, but to date, not much has been discovered about the underlying mechanisms. The 2011 Nobel Prize in Physiology or Medicine was awarded to the works that discovered the activation of innate immunity via pattern recognition receptors (PRRs), and the critical role of dendritic cells in adaptive immunity. These works have revolutionized our understanding of the immune system in the gut, and open up new research fields leading a way to improve prevention, vaccination and treatment against infection, cancer and inflammatory diseases. Intestinal epithelial cells (IECs) and antigen presenting cells (APCs) express a range of PRRs that is specialized to recognize microbe-associated molecular patterns (MAMPs) from both pathogens and non-pathogenic microorganisms. Toll-like receptors (TLRs), the best characterized PRRs, play a key role in pathogen recognition and the induction of innate effectors and inflammation. Moreover, recent findings suggest that TLRs are important in intestinal homeostasis and appear to play a role in tolerance to foreign antigens and commensal bacteria as well as in the immunoregulatory effect of probiotic lactic acid bacteria (LAB) (immunobiotics) and immunostimulatory nucleic acid sequences (immunogenics). In this talk, we will present our recent research on the development of molecular immunoassay systems for the selection and evaluation of immunobiotic LAB, and immunogenics. Moreover, we will describe our work studying the function of TLRs and TLRs negative regulators in the development of immunotolerance mediated by LAB in IECs and APCs. Our results highlight role of PRRs in the therapeutic effect of immunobiotics and immunogenics and advance in the understanding of the molecular mechanisms involved in the beneficial effect of immunobiotic LAB.