The paper explains that mast cells, which are immune cells involved in allergies and defense, have several Toll‑like receptors (TLRs) that detect microbes. The antimicrobial peptide LL‑37 can change how these TLRs are expressed on mast cells, potentially affecting how the cells respond to bacteria, viruses, and allergens. However, the study is basic science and doesn’t give dosing or practical tips for using LL‑37.

Taking into account the role of mast cells in different physiological and pathological processes, as well as in host defense it seems very important to recognize mast cell receptors and their role in activation of these cells. In the last few years it has been indicated that mast cells can express Toll-like receptors (TLRs), molecules that play an essential role in the activation of innate immune response to microbial pathogens and take part in the development of adaptive immunity, as well. It has been defined that mast cells express TLR2, TLR4, TLR1 and TLR6. There is also some data proving that mast cells possess TLR5, TLR3 and TLR9 molecules. The presence of TLR7, TLR9, and TLR10 on mast cells is still unclear. Some data indicate that TLR expression by mast cells can be modulated by various cytokines, such as granulocyte-macrophage colony stimulating factor (GM-CSF) and interferon (IFN)-g, cathelicidin LL-37 as well as by some bacterial components. It is now established that TLRs are involved in mast cell response to bacterial stimulation; some data also indicate that TLRs take part in virus-induced mast cell activation. What is more, it is now suggested that TLRs might regulate IgE-FceRI-dependent mast cell stimulation. Further research is needed to fully understand and describe the role of TLRs in mast cell biology.