Skin ulcers-microbiota-infected ulcers

It is nowadays established that the modifications of the skin barrier and/or the skin’s immune system are the inevitable cause of an alteration of the host-microbiome relationship followed by a proliferation of the opportunistic and/or pathogenic flora and an uncontrolled immune response which, in turn, might amplify the pathological case itself. The ulcer allows the skin and the environmental microbiome to penetrate the tissues and find optimal conditions to grow; it is believed that the interaction between host, microbiome and the skin might have a positive role in modulating the immune response in the wound healing process or that, at least, its composition might significantly affect it. Wound healing is a complex process that includes many interconnecting and overlapping mechanisms, including cell migration and proliferation, the release of pro- and anti-inflammatory cytokines, growth factors, synthesis, and degradation of the extracellular matrix. An imbalance of these complex mechanisms, regulated by many different signaling pathways, strongly affects the result which, in turn, is correlated with the inflammatory status and the immune response. The relationship microbe-microbe and microbe-skin; the role of the biofilm, defined as an organized aggregate of microorganisms and their communication system through Quorum-Sensing; the progression of a colonized wound towards infection; the role of the host; the microenvironment’s impact on the host and on the microbiota and an overview of future applications are the objects of this scientific review which aims at discussing wound healing as a perfect, inseparable balance between host, skin and microbiota.