Mucosal-associated invariant T(MAIT)cells are a population of evolutionarily conserved“innate”T cells that express the invariant T-cell receptor(TCR)α-chain Vα7.2-Jα33.MAIT cells are capable of rapidly producing ...Mucosal-associated invariant T(MAIT)cells are a population of evolutionarily conserved“innate”T cells that express the invariant T-cell receptor(TCR)α-chain Vα7.2-Jα33.MAIT cells are capable of rapidly producing several cytokines,including interferon gamma(IFNy),tumour necrosis factor alpha(TNFa)and interleukin 17(IL-17).1 MAIT cells,in particular IL-17-producing subsets,have been implicated in numerous chronic inflammatory diseases including rheumatoid arthritis,ankylosing spondylitis and psoriasis.2 We have previously described alterations in MAIT cell cytokine profiles in obesity,including reduced IFNy production and elevated IL-17 production.3 More recently,we have reported alterations in MAIT cell metabolism in patients with obesity that underpin the loss of IFNy production by MAIT cells.展开更多
Type 2 diabetes(T2D)is highly associated with obesity.However,the factors that drive the transition from excessive weight gain to glucose metabolism disruption are still uncertain and seem to revolve around systemic i...Type 2 diabetes(T2D)is highly associated with obesity.However,the factors that drive the transition from excessive weight gain to glucose metabolism disruption are still uncertain and seem to revolve around systemic immune disorder.Mucosal-associated invariant T(MAIT)cells,which are innate-like T cells that recognize bacterial metabolites,have been reported to be altered in obese people and to lead to metabolic dysfunction during obesity.By studying the immunophenotypes of blood MAIT cells from a cross-sectional cohort of obese participants with/without T2D,we found an elevation in CD27^(-)negative(CD27−)MAIT cells producing a high level of IL-17 under T2D obese conditions,which could be positively correlated with impaired glucose metabolism in obese people.We further explored microbial translocation caused by gut barrier dysfunction in obese people as a triggering factor of MAIT cell abnormalities.Specifically,accumulation of the bacterial strain Bacteroides ovatus in the peripheral blood drove IL-17^(-)producing CD27−MAIT cell expansion and could be associated with T2D risk in obese individuals.Overall,these results suggest that an aberrant gut microbiota–immune axis in obese people may drive or exacerbate T2D.Importantly,CD27−MAIT cell subsets and Bacteroides ovatus could represent targets for novel interventional strategies.Our findings extend current knowledge regarding the clinical relevance of body mass index(BMI)-associated variation in circulating MAIT cells to reveal the role of these cells in obesity-related T2D progression and the underlying cellular mechanisms.展开更多
Opportunistic bacteria in apical periodontitis (AP) may pose a risk for systemic dissemination.Mucosal-associated invariant T (MAIT) cells are innate-like T cells with a broad and potent antimicrobial activity importa...Opportunistic bacteria in apical periodontitis (AP) may pose a risk for systemic dissemination.Mucosal-associated invariant T (MAIT) cells are innate-like T cells with a broad and potent antimicrobial activity important for gut mucosal integrity.It was recently shown that MAIT cells are present in the oral mucosal tissue,but the involvement of MAIT cells in AP is unknown.Here,comparison of surgically resected AP and gingival tissues demonstrated that AP tissues express significantly higher levels of Vα7.2-Jα33,Vα7.2- Jα20,Vα7.2-Jα12,Cα and tumour necrosis factor (TNF),interferon (IFN)-γ and interleukin (IL)-17A transcripts,resembling a MAIT cell signature.Moreover,in AP tissues the MR1-restricted MAIT cells positive for MR1–5-OP-RU tetramer staining appeared to be of similar levels as in peripheral blood but consisted mainly of CD4^+ subset.Unlike gingival tissues,the AP microbiome was quantitatively impacted by factors like fistula and high patient age and had a prominent riboflavin-expressing bacterial feature.When merged in an integrated view,the examined immune and microbiome data in the sparse partial least squares discriminant analysis could identify bacterial relative abundances that negatively correlated with Vα7.2-Jα33,Cα,and IL-17A transcript expressions in AP,implying that MAIT cells could play a role in the local defence at the oral tissue barrier.In conclusion,we describe the presence of MAIT cells at the oral site where translocation of oral microbiota could take place.These findings have implications for understanding the immune sensing of polymicrobial-related oral diseases.展开更多
基金supported by the National Children’s Research Centre.
文摘Mucosal-associated invariant T(MAIT)cells are a population of evolutionarily conserved“innate”T cells that express the invariant T-cell receptor(TCR)α-chain Vα7.2-Jα33.MAIT cells are capable of rapidly producing several cytokines,including interferon gamma(IFNy),tumour necrosis factor alpha(TNFa)and interleukin 17(IL-17).1 MAIT cells,in particular IL-17-producing subsets,have been implicated in numerous chronic inflammatory diseases including rheumatoid arthritis,ankylosing spondylitis and psoriasis.2 We have previously described alterations in MAIT cell cytokine profiles in obesity,including reduced IFNy production and elevated IL-17 production.3 More recently,we have reported alterations in MAIT cell metabolism in patients with obesity that underpin the loss of IFNy production by MAIT cells.
基金This study was funded by the National Key R&D Program of China(2017YFA0105803)the National Natural Science Foundation of China(32000621 and 81770826)+3 种基金the Key Area R&D Program of Guangdong Province(2019B020227003)the Science and Technology Plan Project of Guangzhou City(202102010338 and 202007040003)the 5010 Clinical Research Projects of Sun Yat-sen University(2015015)the Dengfeng Plan High-level Hospital Construction Opening Project of Foshan Fourth People’s Hospital(FSSYKF-2020009).
文摘Type 2 diabetes(T2D)is highly associated with obesity.However,the factors that drive the transition from excessive weight gain to glucose metabolism disruption are still uncertain and seem to revolve around systemic immune disorder.Mucosal-associated invariant T(MAIT)cells,which are innate-like T cells that recognize bacterial metabolites,have been reported to be altered in obese people and to lead to metabolic dysfunction during obesity.By studying the immunophenotypes of blood MAIT cells from a cross-sectional cohort of obese participants with/without T2D,we found an elevation in CD27^(-)negative(CD27−)MAIT cells producing a high level of IL-17 under T2D obese conditions,which could be positively correlated with impaired glucose metabolism in obese people.We further explored microbial translocation caused by gut barrier dysfunction in obese people as a triggering factor of MAIT cell abnormalities.Specifically,accumulation of the bacterial strain Bacteroides ovatus in the peripheral blood drove IL-17^(-)producing CD27−MAIT cell expansion and could be associated with T2D risk in obese individuals.Overall,these results suggest that an aberrant gut microbiota–immune axis in obese people may drive or exacerbate T2D.Importantly,CD27−MAIT cell subsets and Bacteroides ovatus could represent targets for novel interventional strategies.Our findings extend current knowledge regarding the clinical relevance of body mass index(BMI)-associated variation in circulating MAIT cells to reveal the role of these cells in obesity-related T2D progression and the underlying cellular mechanisms.
文摘Opportunistic bacteria in apical periodontitis (AP) may pose a risk for systemic dissemination.Mucosal-associated invariant T (MAIT) cells are innate-like T cells with a broad and potent antimicrobial activity important for gut mucosal integrity.It was recently shown that MAIT cells are present in the oral mucosal tissue,but the involvement of MAIT cells in AP is unknown.Here,comparison of surgically resected AP and gingival tissues demonstrated that AP tissues express significantly higher levels of Vα7.2-Jα33,Vα7.2- Jα20,Vα7.2-Jα12,Cα and tumour necrosis factor (TNF),interferon (IFN)-γ and interleukin (IL)-17A transcripts,resembling a MAIT cell signature.Moreover,in AP tissues the MR1-restricted MAIT cells positive for MR1–5-OP-RU tetramer staining appeared to be of similar levels as in peripheral blood but consisted mainly of CD4^+ subset.Unlike gingival tissues,the AP microbiome was quantitatively impacted by factors like fistula and high patient age and had a prominent riboflavin-expressing bacterial feature.When merged in an integrated view,the examined immune and microbiome data in the sparse partial least squares discriminant analysis could identify bacterial relative abundances that negatively correlated with Vα7.2-Jα33,Cα,and IL-17A transcript expressions in AP,implying that MAIT cells could play a role in the local defence at the oral tissue barrier.In conclusion,we describe the presence of MAIT cells at the oral site where translocation of oral microbiota could take place.These findings have implications for understanding the immune sensing of polymicrobial-related oral diseases.
