Eosinophils, Inflammation and Immunity

在2020财年，我们就这一主题撰写了5篇稿件，如下：

In Fiscal Year (FY) 2020, we contributed to five (5) manuscripts on this topic as follows: Manuscript #1: Title: Frontline science: cytokine-mediated developmental phenotype of mouse eosinophils: IL-5-associated expression of the Ly6G/Gr1 surface antigen. Eosinophils have broad and extensive immunomodulatory capacity; recent studies have focused on the roles of distinct eosinophil subsets in specific tissue microenvironments. Ly6G is a glycosylphosphatidylinositol (GPI)-linked leukocyte surface Ag understood primarily as a marker of mouse neutrophils, although its full function is not known. Here, we show that Ly6G/Gr1, detected by mAbs 1A8 (anti-Ly6G) and RB6-8C5 (anti-Gr1), is detected prominently on a significant fraction of eosinophils from mouse bone marrow and bone marrow-derived culture, with fractions expressing this Ag increasing in IL-5-enriched microenvironments. Among our findings, we identified SiglecF+ Gr1+ eosinophils in bone marrow from naive, allergen-challenged and IL-5 transgenic mice; SiglecF+ Gr1+ eosinophils were also prominent ex vivo in bone marrow-derived eosinophils (bmEos) in IL-5-enriched culture. Reducing the IL-5 concentration 20-fold had no impact on the rate of generation of SiglecF+ bmEos but did result in a marked increase in the Gr1- fraction (from 17.4 2% to 30 2.3%, ***P < 0.005). Reducing the IL-5 concentration also enhanced chemotaxis; SiglecF+ Gr1- bmEos were considerably more responsive to eotaxin-1 than were their SiglecF+ Gr1+ counterparts. These results suggest that (i) IL-5 regulates the expression of Ly6G/Gr1, either directly or indirectly, in cells of the eosinophil lineage, (ii) eosinophils generated in response to high concentrations of IL-5 can be distinguished from those generated under homeostatic conditions by expression of the Ly6G/Gr1 cell surface Ag, and (iii) expression of Ly6G/Gr1 may have an impact on function, directly or indirectly, including the potential to undergo chemotaxis in response to eotaxin-1. Ref: Limkar, A. R., E. Mai, A. C. Sek, C. M. Percopo, H. F. Rosenberg. 2020. J. Leukoc. Biol. 107: 367-377. Manuscript #2: Title: The Cellular Functions of Eosinophils Collegium International Allergologicum (CIA) Update. Eosinophils and their secretory mediators play an important role in the pathogenesis of infectious and inflammatory disorders. Although eosinophils are largely evolutionarily conserved, their physiologic functions are not well understood. Given the availability of new eosinophil-targeted depletion therapies, there has been a renewed interest in understanding eosinophil biology as these strategies may result in secondary disorders when applied over long periods of time. Recent data suggest that eosinophils are not only involved in immunological effector functions but also carry out tissue protective and immunoregulatory functions that actively contribute to the maintenance of homeostasis. Prolonged eosinophil depletion may therefore result in the development of secondary disorders. Here, we review recent literature pointing to important roles for eosinophils in promoting immune defense, antibody production, activation of adipose tissue, and tissue remodeling and fibrosis. We also reflect on patient data from clinical trials that feature anti-eosinophil therapeutics. Ref: Simon, H. U., S. Yousefi, N. Germic, I. Arnold, A. Haczku, A. V. Karaulov, D. Simon, and H. F. Rosenberg. 2020. Int. Archives Allergy Immunol. 181: 11-23 Manuscript #3: Title: Detection of Mouse Eosinophils in Tissue by Flow Cytometry and Isolation by Fluorescence-Activated Cell Sorting. Flow cytometry is a critical tool that can be employed to detect unique cells in and isolate cells from tissues based on their antigen profiles. While mouse eosinophils can be readily detected by one or more distinct antigen profiles, many of these strategies do not result in accurate eosinophil counts. We present here our basic protocol, which permits quantitative detection of eosinophils in and isolation of eosinophils from bone marrow, spleen, lung of allergen-challenged wild-type and unchallenged IL5 transgenic mice, and, with small protocol variations, from small intestines and muscle tissue, the latter from infiltrates characteristic of muscular dystrophy (mdx) mice. Ref: Percopo, C. M., A. R. Limkar, A. C. Sek, and H. F. Rosenberg. 2020. Walsh, G. A., ed. Eosinophils. Methods in Molecular Biology, Humana Press. Manuscript #4: Title: Generation of Mouse Eosinophils in Tissue Culture from Unselected Bone Marrow Progenitors. Human eosinophilic leukocytes are found in peripheral blood and tissues at homeostasis and at elevated levels in atopic disorders. As inbred strains of mice (Mus musculus) are currently the models of choice for the study of disease mechanisms in vivo, a full understanding of mouse eosinophils is critical for interpretation of experimental findings. Toward this end, several years ago we presented a protocol for generating mouse eosinophils in tissue culture from unselected bone marrow progenitors. This method has been implemented widely and has proven to be effective for generating phenotypically mature eosinophils from numerous mouse strains and genotypes. Here we provide a detailed version of this protocol, along with suggestions and notes for its careful execution. We have also included several protocol variations and suggestions for improvements. Ref: Mai, E., A. R. Limkar, C. M. Percopo, and H. F. Rosenberg. 2020. Walsh, G. A., ed. Eosinophils. Methods in Molecular Biology, Humana Press. Manuscript #5: Title: Introduction to Eosinophils The eosinophil is an enigmatic cell with a continuing ability to fascinate. A considerable history of research endeavour on eosinophil biology stretches from the present time back to the 19th century. Perhaps one of the most fascinating aspects of the eosinophil is how accumulating knowledge has changed the perception of its function from passive bystander, modulator of inflammation, to potent effector cell loaded with histotoxic substances through to more recent recognition that it can act as both a positive and negative regulator of complex events in both innate and adaptive immunity. This book consists of 20 chapters written by experts in the field of eosinophil biology that provide comprehensive clearly written protocols for techniques designed to underpin research into the function of the eosinophil in health and disease. Ref: Lacy, P., H. F. Rosenberg, and G. A. Walsh. 2020. Introduction to Eosinophils. Eosinophils. Methods in Molecular Biology, Humana Press.