Researchers at the University of Calgary in Canada have found a promising new method to treat bacterial skin infections. In a recent paper published in the journal Nature, researchers described their new insights, which may lead to new treatments for bacterial infections and skin wounds. Traditionally, researchers believe that both neutrophils and monocytes are responsible for removing bacteria from infected areas of the skin. When these cells work together, they become the first line of defense of the immune system in the body. However, new research shows that monocytes themselves can promote faster wound healing. Monocytes help healing by regulating leptin levels and vascular growth during wound repair. They also produce growth hormone releasing hormone, a hormone that helps wounds heal more effectively. Ghrelin is a hormone produced by the stomach during hunger; Leptin is a hormone produced by fat cells after eating and feeling full. For a long time, the balance between these two hormones has been considered to be the key to metabolism and diet, but people have never known its relationship with immune mechanism and tissue repair. Using in vivo microscopy, researchers were able to visualize the immune response to Staphylococcus aureus in animal prototypes. Staphylococcus aureus is a bacterium commonly found on the skin or nose of healthy people and may be a catalyst for various diseases related to skin and tissue infections, such as abscesses or boils. In some cases, this bacteria may cause severe infections such as pneumonia and endocarditis. After Staphylococcus aureus infection, the body will assemble useful immune cells, neutrophils and monocytes. Neutrophils clear bacteria, while monocytes help repair tissue. In the absence of monocytes, leptin increases, leading to vascular growth at the time of infection, and the result may be delayed healing and scarring. In contrast, monocytes release ghrelin at the site of infection, preventing leptin driven vascular overgrowth, thereby promoting tissue repair. The researchers said that this study enhanced the role of monocytes in wound repair, challenged the current view that neutrophils and monocytes clear bacteria, indicated a paradigm shift, and opened the door for the introduction of metabolic hormones (ghrelin and leptin) in immunology and microbiology. (outlook new era)