AIM:Regulatory T cells(Tregs)are a specialized subset of CD4^(+)T cells primarily involved in im⁃munosuppressive functions.AMP-activated protein kinase(AMPK)serves as a metabolic sensor that governs the differen⁃tiati...AIM:Regulatory T cells(Tregs)are a specialized subset of CD4^(+)T cells primarily involved in im⁃munosuppressive functions.AMP-activated protein kinase(AMPK)serves as a metabolic sensor that governs the differen⁃tiation,maturation,and immune functions of Tregs through metabolic reprogramming.However,the impact of AMPKα1(the catalytic subunit of AMPK)knockout specifically in Tregs on the host's immune microenvironment remains largely un⁃explored.METHODS:Histological changes in immune organs were assessed using HE staining.The types of immune cells and their relative population percentages in immune organs and blood were quantified through flow cytometry in both AMPKα1flox/flox(AMPKα1^(fl/fl))mice and Treg-specific AMPKα1 knockout mice(AMPKα1^(fl/fl)Foxp3^(cre)mice).RESULTS:Compared to AMPKα1^(fl/fl)mice,the percentage of eosinophils in the bone marrow of AMPKα1^(fl/fl)Foxp3^(cre)mice was significant⁃ly reduced.Additionally,while the thymus of AMPKα1^(fl/fl)Foxp3^(cre)mice exhibited normal structure,both its size and the ratio of thymus weight to body weight were significantly decreased.The knockout of AMPKα1 in Tregs led to a notable reduction in the total percentage of immature double-negative(DN)cells.Consequently,the percentage of CD4^(+)T cells derived from these DN cells also decreased,even though the percentages of DN1 and DN4 cells were higher in the thymus of AMPKα1^(fl/fl)Foxp3^(cre)mice compared to AMPKα1^(fl/fl)mice.Importantly,the proportion of Siglec-F+CD11b^(+)eosinophils in the thymus was significantly lower in AMPKα1^(fl/fl)Foxp3^(cre)mice.Knockout of AMPKα1 in Tregs resulted in a marked increase in the percentage of CD4^(+)T cells in peripheral blood,alongside a decrease in the proportion of mature CD8^(+)T cells.Similarly,the proportion of CD4^(+)T cells in the spleen of AMPKα1^(fl/fl)Foxp3^(cre)mice was elevated compared to AMPKα1^(fl/fl)mice.In contrast,the proportion of neutrophils significantly decreased,while mononuclear cell proportions increased in the spleen of AMPKα1^(fl/fl)Foxp3^(cre)mice.In lymph nodes,the medullary boundaries in AMPKα1^(fl/fl)Foxp3^(cre)mice were blurred,and the lymphoid follicles were missing,a feature not observed in AMPKα1^(fl/fl)mice.Furthermore,the knockout of AMPKα1 in Tregs reduced the CD3^(+)T cell population,particularly the CD8^(+)T cell population,in lymph nodes.Although the mature Treg cell population was significantly lower in AMPKα1^(fl/fl)Foxp3^(cre)mice,the percentage of CD4^(+)T cells was markedly in⁃creased.In contrast,there was no statistically significant difference in granulocyte populations between AMPKα1^(fl/fl)Foxp3^(cre)and AMPKα1^(fl/fl)mice.CONCLUSION:The populations of mature Tregs,CD8^(+)T cells and eosinophils in various im⁃mune organs were significantly altered in mice with Treg-specific AMPKα1 knockout,suggesting a potential remodeling of the host immune microenvironment in response to inflammatory stimuli.展开更多
基金Supported by the National Natural Science Foundation of China(No.81800423)the Guangdong Medical Science and Technology Research project(No.B2022102)。
文摘AIM:Regulatory T cells(Tregs)are a specialized subset of CD4^(+)T cells primarily involved in im⁃munosuppressive functions.AMP-activated protein kinase(AMPK)serves as a metabolic sensor that governs the differen⁃tiation,maturation,and immune functions of Tregs through metabolic reprogramming.However,the impact of AMPKα1(the catalytic subunit of AMPK)knockout specifically in Tregs on the host's immune microenvironment remains largely un⁃explored.METHODS:Histological changes in immune organs were assessed using HE staining.The types of immune cells and their relative population percentages in immune organs and blood were quantified through flow cytometry in both AMPKα1flox/flox(AMPKα1^(fl/fl))mice and Treg-specific AMPKα1 knockout mice(AMPKα1^(fl/fl)Foxp3^(cre)mice).RESULTS:Compared to AMPKα1^(fl/fl)mice,the percentage of eosinophils in the bone marrow of AMPKα1^(fl/fl)Foxp3^(cre)mice was significant⁃ly reduced.Additionally,while the thymus of AMPKα1^(fl/fl)Foxp3^(cre)mice exhibited normal structure,both its size and the ratio of thymus weight to body weight were significantly decreased.The knockout of AMPKα1 in Tregs led to a notable reduction in the total percentage of immature double-negative(DN)cells.Consequently,the percentage of CD4^(+)T cells derived from these DN cells also decreased,even though the percentages of DN1 and DN4 cells were higher in the thymus of AMPKα1^(fl/fl)Foxp3^(cre)mice compared to AMPKα1^(fl/fl)mice.Importantly,the proportion of Siglec-F+CD11b^(+)eosinophils in the thymus was significantly lower in AMPKα1^(fl/fl)Foxp3^(cre)mice.Knockout of AMPKα1 in Tregs resulted in a marked increase in the percentage of CD4^(+)T cells in peripheral blood,alongside a decrease in the proportion of mature CD8^(+)T cells.Similarly,the proportion of CD4^(+)T cells in the spleen of AMPKα1^(fl/fl)Foxp3^(cre)mice was elevated compared to AMPKα1^(fl/fl)mice.In contrast,the proportion of neutrophils significantly decreased,while mononuclear cell proportions increased in the spleen of AMPKα1^(fl/fl)Foxp3^(cre)mice.In lymph nodes,the medullary boundaries in AMPKα1^(fl/fl)Foxp3^(cre)mice were blurred,and the lymphoid follicles were missing,a feature not observed in AMPKα1^(fl/fl)mice.Furthermore,the knockout of AMPKα1 in Tregs reduced the CD3^(+)T cell population,particularly the CD8^(+)T cell population,in lymph nodes.Although the mature Treg cell population was significantly lower in AMPKα1^(fl/fl)Foxp3^(cre)mice,the percentage of CD4^(+)T cells was markedly in⁃creased.In contrast,there was no statistically significant difference in granulocyte populations between AMPKα1^(fl/fl)Foxp3^(cre)and AMPKα1^(fl/fl)mice.CONCLUSION:The populations of mature Tregs,CD8^(+)T cells and eosinophils in various im⁃mune organs were significantly altered in mice with Treg-specific AMPKα1 knockout,suggesting a potential remodeling of the host immune microenvironment in response to inflammatory stimuli.
