title: CD44 enhances macrophage phagocytosis and plays a protective role in Streptococcus equi subsp. zooepidemicus infection.
abstract: Streptococcus equi subsp. zooepidemicus (S. zooepidemicus) is an important pathogen associated with a wide range of diseases in many mammalian species. CD44 is a transmembrane adhesion molecule involved in innate and adaptive immune responses. The aim of this study was to determine the protective role of CD44 during S. zooepidemicus infection. CD44-deficient mice exhibited reduced macrophage accumulation in the bronchoalveolar space and enhanced bacterial outgrowth and dissemination, which resulted in reduced mouse survival. An in vitro analysis revealed that CD44 can directly bind to S. zooepidemicus. Additionally, S. zooepidemicus interacted with macrophage-associated CD44, as reflected by the reduced uptake of S. zooepidemicus by CD44-deficient macrophages. These data suggest that CD44 contributes to effective antibacterial defense during S. zooepidemicus infection, thereby limiting the accompanying injury and death.
authors.affiliation: School of Life Science, Foshan University, Guangdong 528231, PR China; State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510006, PR China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Fu
authors.affiliation: State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510006, PR China.
authors.forename: Zigong
authors.initials: Z
authors.lastname: Wei
authors.affiliation: State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510006, PR China.
authors.forename: Pingping
authors.initials: P
authors.lastname: Xiao
authors.affiliation: State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510006, PR China.
authors.forename: Yaosheng
authors.initials: Y
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510006, PR China. Electronic address: liuxh8@mail.sysu.edu.cn.
authors.forename: Xiaohong
authors.initials: X
authors.lastname: Liu
mesh_terms: D000818:Animals; D006734:Horse Diseases / Q000235:genetics* / Q000276:immunology*; D006736:Horses; D018960:Hyaluronan Receptors / Q000235:genetics / Q000378:metabolism*; D007109:Immunity / Q000235:genetics*; D008264:Macrophages / Q000276:immunology* / Q000382:microbiology; D051379:Mice; D010587:Phagocytosis / Q000235:genetics / Q000276:immunology; D013290:Streptococcal Infections / Q000235:genetics / Q000276:immunology / Q000662:veterinary*; D018502:Streptococcus equi / Q000502:physiology; D016019:Survival Analysis
chemical_list: D018960:Hyaluronan Receptors
keywords: CD44; Macrophages; Phagocytosis; Streptococcus equi subsp. zooepidemicus