Organization of the Skin Immune System and Compartmentalized Immune Responses in Infectious Diseases

Abstract

SUMMARY The skin is an organ harboring several types of immune cells that participate in innate and adaptive immune responses. The immune system of the skin comprises both skin cells and professional immune cells that together constitute what is designated skin-associated lymphoid tissue (SALT). In this review, I extensively discuss the organization of SALT and the mechanisms involved in its responses to infectious diseases of the skin and mucosa. The nature of these SALT responses, and the cellular mediators involved, often determines the clinical course of such infections. I list and describe the components of innate immunity, such as the roles of the keratinocyte barrier and of inflammatory and natural killer cells. I also examine the mechanisms involved in adaptive immune responses, with emphasis on new cytokine profiles, and the role of cell death phenomena in host-pathogen interactions and control of the immune responses to infectious agents. Finally, I highlight the importance of studying SALT in order to better understand host-pathogen relationships involving the skin and detail future directions in the immunological investigation of this organ, especially in light of recent findings regarding the skin immune system.

The Global Emergency of Novel Coronavirus (SARS-CoV-2): An Update of the Current Status and Forecasting

“…Delivering vaccine components to a defined skin microenvironment improves safety by reducing systemic exposure, allowing to reach high vaccine concentrations with a relatively low dose of antigen [212,213]. Furthermore, the skin delivery strategy promotes strong and long-lasting antigen-specific antibody responses due to both the high immunogenicity [214][215][216][217][218] and the redundant immunoregulatory circuits of the skin [217,219,220]. Given the urgent need for COVID-19 vaccines, MNAs strategy seems to be a promising immunization approach against coronavirus infection including SARS, MERS and other emerging infectious diseases.…”

GM-CSF and HMGB1 level were associated with the clinical characteristics and prognosis of childhood refractory mycoplasma pneumoniae pneumonia

“…Despite being only a subsystem in the more basic and all-compassing system maintaining integrity, the adaptive immune system plays a key role in recognizing pathogens and distinguishing dead cells, thus clear harmful substances and block secondary damage [5]. It is reported that pathogenassociated molecular pattern molecules (PAMPs) and damage-associated molecular pattern molecules (DAMPs) are the most important adjuvants for adaptive immune system [6]. PAMPs has been identified galore, while there are only two types of typical DAMP as so far: high mobility Group Box 1 (HMGB1) protein and adenosine triphosphate proteins (ATP) [7].…”

A genome-wide association study highlights a regulatory role forIFNG-AS1contributing to cutaneous leishmaniasis in Brazil

“…Keratin 80 encoded by KRT80 is a type II epithelial keratin that is an intermediate filament protein responsible for structural integrity of epithelial cells and has biased expression in skin keratinocytes [52]. At the time of infection pathogens invading the skin can cause keratinocytes to produce chemokines which attract monocytes, natural killer cells, T cells, and dendritic cells [53].…”