AUTHOR=He Ran , Zhang Qian , Xu Luyang , Guo Maochuan , Gu Xiaobin , Xie Yue , Xu Jing , Shen Zhaoli 

TITLE=Characterization of a novel galectin in Sarcoptes scabiei and its role in regulating macrophage functions

JOURNAL=Frontiers in Microbiology

VOLUME=14

YEAR=2023

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2023.1251475

DOI=10.3389/fmicb.2023.1251475

ISSN=1664-302X

ABSTRACT=<p><italic>Sarcoptes scabiei</italic> (<italic>S. scabiei</italic>) endangers human and other mammalian health. There has been limited research into <italic>S. scabiei</italic> pathogenic mechanisms and the immunological interaction between <italic>S. scabiei</italic> and hosts. Galectins have critical roles in biological processes such as cell adhesion, signal transduction, and immune response mediation. Galectins of <italic>S. scabiei</italic> (<italic>Ss</italic>Galectins) were cloned, expressed, and identified, and their transcriptional levels in <italic>S. scabiei</italic> were measured at various developmental stages. Fluorescent tissue localization was performed on <italic>Ss</italic>Galectins of <italic>S. scabiei</italic> and scabies skin. A mouse AD model was constructed to evaluate the effect of r<italic>Ss</italic>Galectins on skin pathogenic changes. Quantitative polymerase chain reaction and enzyme-linked immunoassay were used to identify macrophage polarization-related components and investigate the immunoregulatory effect of r<italic>Ss</italic>Galectins on mouse macrophages. The results demonstrated that the <italic>S. scabiei</italic> infection causes macrophage infiltration in the scabies skin. The r<italic>Ss</italic>Galectins displayed strong reactogenicity, and distinct genes of the <italic>Ss</italic>Galectins were differently expressed in different developmental stages of <italic>S. scabiei</italic>. Fluorescence tissue localization revealed that the <italic>Ss</italic>Galectins were mainly in the mouthparts, intestines, and body surface. Additionally, <italic>S. scabiei</italic> could secrete <italic>Ss</italic>Galectins into the infected skin, proving that <italic>Ss</italic>Galectins were excretion and secretion proteins of <italic>S. scabiei</italic>. In the mouse atopic dermatitis model, cutaneous macrophage infiltration and inflammation increase after r<italic>Ss</italic>Galectins injection. Simultaneously, when r<italic>Ss</italic>Galectins acted on bone marrow-derived macrophages, M1 macrophage-related polarization factors IL-1β, IL-6, and inducible nitric oxide synthase all increased, demonstrating that r<italic>Ss</italic>Galectins can induce M1 polarization and produce pro-inflammatory cytokines. In conclusion, the <italic>Ss</italic>Galectins are involved in the pathogenic process of <italic>S. scabiei</italic> by regulating the polarization of host macrophages to the M1 type when <italic>S. scabiei</italic> invade the host and promoting the incidence and development of the host's inflammatory response. This study offers fresh light on the pathogenic process of scabies mites, investigates the immunological interaction mechanism between <italic>S. scabiei</italic> and the host, and offers new insights into <italic>S. scabiei</italic> prevention and therapy.</p>