Indoleamine 2, 3-dioxygenase (IDO) is a rate-limiting enzyme for the tryptophan catabolism. In human and murine cells, IDO inhibits antigen-specific T cell proliferation in vitro and suppresses T cell responses to fet...Indoleamine 2, 3-dioxygenase (IDO) is a rate-limiting enzyme for the tryptophan catabolism. In human and murine cells, IDO inhibits antigen-specific T cell proliferation in vitro and suppresses T cell responses to fetal alloantigens during murine pregnancy. In mice, IDO expression is an inducible feature of specific subsets of dendritic cells (DCs), and is important for T cell regulatory properties. However, the effect of IDO and tryptophan deprivation on DC func- tions remains unknown. We report here that when tryptophan utilization was prevented by a pharmacological inhibitor of IDO, 1-methyl tryptophan (1MT), DC activation induced by pathogenic stimulus lipopolysaccharide (LPS) or inflam- matory cytokine TNF-α was inhibited both phenotypically and functionally. Such an effect was less remarkable when DC was stimulated by a physiological stimulus, CD40 ligand. Tryptophan deprivation during DC activation also regu- lated the expression of CCR5 and CXCR4, as well as DC responsiveness to chemokines. These results suggest that tryptophan usage in the microenvironment is essential for DC maturation, and may also play a role in the regulation of DC migratory behaviors.展开更多
Background: Indoleamine 2,3-dioxygenase 1 (IDO1) and tryptophan (Trp)catabolism have been demonstrated to play an important role in tumor immunosuppression. This study examined the expression and catalytic activity of...Background: Indoleamine 2,3-dioxygenase 1 (IDO1) and tryptophan (Trp)catabolism have been demonstrated to play an important role in tumor immunosuppression. This study examined the expression and catalytic activity of IDO1 in penilesquamous cell carcinoma (PSCC) and explored their clinical significance.Methods: IDO1 expression level, serum concentrations of Trp and kynurenine (Kyn)were examined in 114 PSCC patients by immunohistonchemistry and solid-phaseextraction-liquid chromatography-tandem mass spectrometry. The survival was analyzed using Kaplan-Meier method and the log-rank test. Hazard ratio of death was analyzed via univariate and multivariate Cox regression. Immune cell types were definedby principal component analysis. The correlativity was assessed by Pearson’s correlation analysis.Results: The expression level of IDO1 in PSCC cells was positively correlatedwith serum Kyn concentration and Kyn/Trp radio (KTR;both P < 0.001) but negatively correlated with serum Trp concentration (P = 0.001). Additionally, IDO1 upregulation in cancer cells and the increase of serum KTR were significantly associated with advanced N stage (both P < 0.001) and high pathologic grade (P = 0.008and 0.032, respectively). High expression level of IDO1 in cancer cells and serumKTR were associated with short disease-specific survival (both P < 0.001). However, besides N stage (hazard radio [HR], 6.926;95% confidence interval [CI],2.458-19.068;P < 0.001) and pathologic grade (HR, 2.194;95% CI, 1.021-4.529;P = 0.038), only serum KTR (HR, 2.780;95% CI, 1.066-7.215;P = 0.036) was anindependent predictor for PSCC prognosis. IDO1 expression was positively correlated with the expression of interferon-𝛾 (IFN𝛾, P < 0.001) and immunosuppressivemarkers (programmed cell death protein 1, cytotoxic T-lymphocyte-associated protein 4 and programmed death-ligand 1 and 2;all P < 0.05), and the infiltration ofimmune cells (including cytotoxic T lymphocytes, regulatory T lymphocytes, tumorassociated macrophages, and myeloid-derived suppressor cells;all P < 0.001) inPSCC tissues. Furthermore, the expression of IDO1 was induced by IFN𝛾 in a dosedependent manner in PSCC cells.Conclusions: IFN𝛾-induced IDO1 plays a crucial role in immunoediting andimmunosuppression in PSCC. Additionally, serum KTR, an indicator of IDO1catabolic activity, can be utilized as an independent prognostic factor for PSCC.展开更多
This study examined whether 1-methyl-tryptophan [1-MT,an indoleamine 2,3-dioxygenase(IDO) inhibitor] could reduce CD4+CD25+ regulatory T cells(Tregs) proliferation and improve the anti-tumor efficacy of dendritic cell...This study examined whether 1-methyl-tryptophan [1-MT,an indoleamine 2,3-dioxygenase(IDO) inhibitor] could reduce CD4+CD25+ regulatory T cells(Tregs) proliferation and improve the anti-tumor efficacy of dendritic cells(DCs) pulsed with tumor cell lysate in the mice bearing pancreatic adenocarcinoma.The models of pancreatic adenocarcinoma were established in C57BL/6 mice by subcutaneous injection of Pan02 cells.Eight mice which were subcutaneously injected with PBS served as control.The expression of IDO was determined in tumor draining lymph nodes(TDLNs) and spleens of the murine pancreatic adenocarcinoma models.The prevalence of Tregs was measured in the TDLNs and spleens before and after 1-MT administration.The dendritic cells were pulsed with tumor cell lysate for preparing DC vaccine.The DC vaccine,as a single agent or in combination with 1-MT,was administered to pancreatic adenocarcinoma mice.The anti-tumor efficacy was determined after different treatments by regular observation of tumor size.The results showed that the levels of IDO mRNA and protein in tumor-bearing mice were significantly higher than those in the normal control mice.The percentage of Tregs in the spleen and TDLNs was also higer in tumor-bearing mice than in normal control mice(P<0.05).Foxp3 expression was significantly lower in the TDLNs and spleens of tumor-bearing mice administrated with 1-MT than that in normal control mice.Furthemore,in the mice that were administered 1-MT plus DC vaccine,the tumor was increased more slowly than in mice treated with DC vaccine or 1-MT alone,or PBS on day 36(P<0.01).Our results indicated that 1-MT may enhance anti-tumor efficacy of dendritic cells pulsed with tumor cell lysate by downregulating the percentage of Tregs.展开更多
A mulfistep conversion system composed of phenol hydroxylase （PHrND） and 2,3-dihydroxy-biphenyl 1,2-dioxygenase （BphCLA_4） was used to synthesize methylcatechols and semialdehydes from o- and m-cresol for the firs...A mulfistep conversion system composed of phenol hydroxylase （PHrND） and 2,3-dihydroxy-biphenyl 1,2-dioxygenase （BphCLA_4） was used to synthesize methylcatechols and semialdehydes from o- and m-cresol for the first time. Docking studies displayed by PyMOL predicted that cresols and methylcatechols could be theoretically transformed by this multistep conversion system~ High performance liquid chromatography mass spectrometry （HPLC-MS） analysis also indicated that the products formed from multistep conversion were the corresponding 3-methylcatechol, 4-methylcatechol, 2- hydroxy-3-methyl-6-oxohexa-2,4-dienoic acid （2- hydroxy-3-methyl-ODA） and 2-hydroxy-5-methyl-6-oxo- hexa-2,4-dienoic acid （2-hydroxy-5-methyl-ODA）. The optimal cell concentrations of the recombinant E. coli strain BL21 （DE3） expressing phenol hydroxylase （PHrND） and 2,3-dihydroxy-biphenyl 1,2-dioxygenase （BphCLA_4） and pH for the multistep conversion of o- and m-cresol were 4.0 （g-L-1 cell dry weight） and pH 8.0, respectively. For the first step conversion, the formation rate of 3- methylcatechol （0.29μmol·L-1·min-1·mg-1cell dry weight） from o-cresol was similarly with that ofmethylca- techols （0.28 μmol·L-1·min-1·mg-1 cell dry weight） from m-cresol by strain PHrND. For the second step conversion, strain BphCLA_4 showed higher formation rate （0.83 μmol·L-1·min-1·mg-1 cell dry weight） for 2-hydroxy-3-methyl- ODA and 2-hydroxy-5-methyl-ODA from m-cresol, which was 1.1-fold higher than that for 2-hydroxy-3-methyl- ODA （0.77 μmol·L-1·min-1·mg-1. mglcell dry weight） from ocresol. The present study suggested the potential application of the multistep conversion system for the production of chemical synthons and high-value products.展开更多
Researches on indoleamine-2,3-dioxygenase-1(IDO1),a neoplastic pathogenesis-related protein,have provided a new angle of view to regulate malignancy-related immunosuppression.However,the therapeutic efficacy of IDO1 i...Researches on indoleamine-2,3-dioxygenase-1(IDO1),a neoplastic pathogenesis-related protein,have provided a new angle of view to regulate malignancy-related immunosuppression.However,the therapeutic efficacy of IDO1 inhibitors is subject to key limitations as both cancer and dendritic cells tend to be trapped in the IDO1-mediated immune dysfunction,which poses challenges to the inhibitory potency of drug regimens in multiple targets.Here,we report on the fabrication technique of a biomimetic nanocarrier that is endowed with the whole array of cancer cell membrane proteins for encapsulating the most used IDO1 probe indoximod(IND).By fully utilizing the homologous adhesion proteins and antigenic motifs on cytomembrane,these nanoparticulate particles are capable of infiltrating tumors and actively accumulating in cancer and dendritic cells,as well as hitching a ride on dendritic cells to tumor-draining lymph nodes.Ultimately,by increasing the distribution of drugs in both tumor cells and dendritic cells in tumor-draining lymph nodes,these formulations greatly enhance the efficacy of IND without the aid of chemotherapeutic drugs,achieving substantial control of tumor growth.Overall,this leverage of bionanotechnology maximizes the therapeutic potential of IND and can provide a theoretical reference for the clinical application of IDO1 inhibitors.展开更多
Combining chemo-therapeutics with immune checkpoint inhibitors facilitates killing cancer cells and activating the immune system through inhibiting immune escape.However,their treatment effects remain limited due to t...Combining chemo-therapeutics with immune checkpoint inhibitors facilitates killing cancer cells and activating the immune system through inhibiting immune escape.However,their treatment effects remain limited due to the compromised accumulation of both drugs and inhibitors in certain tumor tissues.Herein,a new poly(acrylamide-co-acrylonitrile-co-vinylimidazole-co-bis(2-methacryloyl)oxyethyl disulfide)(PAAVB)polymer-based intelligent platform with controllable upper critical solution temperature(UCST)was used for the simultaneous delivery of paclitaxel(PTX)and curcumin(CUR).Additionally,a hyaluronic acid(HA)layer was coated on the surface of PAAVB NPs to target the CD44-overexpressed tumor cells.The proposed nanomedicine demonstrated a gratifying accumulation in tumor tissue and uptake by cancer cells.Then,the acidic microenvironment and high level of glutathione(GSH)in cancer cells could spontaneously decrease the UCST of polymer,leading to the disassembly of the NPs and rapid drug release at body temperature without extra-stimuli.Significantly,the released PTX and CUR could induce the immunogenic cell death(ICD)to promote adaptive anti-tumor immunogenicity and inhibit immunosuppression through suppressing the activity of indoleamine 2,3-dioxygenase 1(IDO1)enzyme respectively.Therefore,the synergism of this intelligent nanomedicine can suppress primary breast tumor growth and inhibit their lung metastasis.展开更多
文摘Indoleamine 2, 3-dioxygenase (IDO) is a rate-limiting enzyme for the tryptophan catabolism. In human and murine cells, IDO inhibits antigen-specific T cell proliferation in vitro and suppresses T cell responses to fetal alloantigens during murine pregnancy. In mice, IDO expression is an inducible feature of specific subsets of dendritic cells (DCs), and is important for T cell regulatory properties. However, the effect of IDO and tryptophan deprivation on DC func- tions remains unknown. We report here that when tryptophan utilization was prevented by a pharmacological inhibitor of IDO, 1-methyl tryptophan (1MT), DC activation induced by pathogenic stimulus lipopolysaccharide (LPS) or inflam- matory cytokine TNF-α was inhibited both phenotypically and functionally. Such an effect was less remarkable when DC was stimulated by a physiological stimulus, CD40 ligand. Tryptophan deprivation during DC activation also regu- lated the expression of CCR5 and CXCR4, as well as DC responsiveness to chemokines. These results suggest that tryptophan usage in the microenvironment is essential for DC maturation, and may also play a role in the regulation of DC migratory behaviors.
基金National Natural Science Foundation of China,Grant/Award Number:81772755
文摘Background: Indoleamine 2,3-dioxygenase 1 (IDO1) and tryptophan (Trp)catabolism have been demonstrated to play an important role in tumor immunosuppression. This study examined the expression and catalytic activity of IDO1 in penilesquamous cell carcinoma (PSCC) and explored their clinical significance.Methods: IDO1 expression level, serum concentrations of Trp and kynurenine (Kyn)were examined in 114 PSCC patients by immunohistonchemistry and solid-phaseextraction-liquid chromatography-tandem mass spectrometry. The survival was analyzed using Kaplan-Meier method and the log-rank test. Hazard ratio of death was analyzed via univariate and multivariate Cox regression. Immune cell types were definedby principal component analysis. The correlativity was assessed by Pearson’s correlation analysis.Results: The expression level of IDO1 in PSCC cells was positively correlatedwith serum Kyn concentration and Kyn/Trp radio (KTR;both P < 0.001) but negatively correlated with serum Trp concentration (P = 0.001). Additionally, IDO1 upregulation in cancer cells and the increase of serum KTR were significantly associated with advanced N stage (both P < 0.001) and high pathologic grade (P = 0.008and 0.032, respectively). High expression level of IDO1 in cancer cells and serumKTR were associated with short disease-specific survival (both P < 0.001). However, besides N stage (hazard radio [HR], 6.926;95% confidence interval [CI],2.458-19.068;P < 0.001) and pathologic grade (HR, 2.194;95% CI, 1.021-4.529;P = 0.038), only serum KTR (HR, 2.780;95% CI, 1.066-7.215;P = 0.036) was anindependent predictor for PSCC prognosis. IDO1 expression was positively correlated with the expression of interferon-𝛾 (IFN𝛾, P < 0.001) and immunosuppressivemarkers (programmed cell death protein 1, cytotoxic T-lymphocyte-associated protein 4 and programmed death-ligand 1 and 2;all P < 0.05), and the infiltration ofimmune cells (including cytotoxic T lymphocytes, regulatory T lymphocytes, tumorassociated macrophages, and myeloid-derived suppressor cells;all P < 0.001) inPSCC tissues. Furthermore, the expression of IDO1 was induced by IFN𝛾 in a dosedependent manner in PSCC cells.Conclusions: IFN𝛾-induced IDO1 plays a crucial role in immunoediting andimmunosuppression in PSCC. Additionally, serum KTR, an indicator of IDO1catabolic activity, can be utilized as an independent prognostic factor for PSCC.
文摘This study examined whether 1-methyl-tryptophan [1-MT,an indoleamine 2,3-dioxygenase(IDO) inhibitor] could reduce CD4+CD25+ regulatory T cells(Tregs) proliferation and improve the anti-tumor efficacy of dendritic cells(DCs) pulsed with tumor cell lysate in the mice bearing pancreatic adenocarcinoma.The models of pancreatic adenocarcinoma were established in C57BL/6 mice by subcutaneous injection of Pan02 cells.Eight mice which were subcutaneously injected with PBS served as control.The expression of IDO was determined in tumor draining lymph nodes(TDLNs) and spleens of the murine pancreatic adenocarcinoma models.The prevalence of Tregs was measured in the TDLNs and spleens before and after 1-MT administration.The dendritic cells were pulsed with tumor cell lysate for preparing DC vaccine.The DC vaccine,as a single agent or in combination with 1-MT,was administered to pancreatic adenocarcinoma mice.The anti-tumor efficacy was determined after different treatments by regular observation of tumor size.The results showed that the levels of IDO mRNA and protein in tumor-bearing mice were significantly higher than those in the normal control mice.The percentage of Tregs in the spleen and TDLNs was also higer in tumor-bearing mice than in normal control mice(P<0.05).Foxp3 expression was significantly lower in the TDLNs and spleens of tumor-bearing mice administrated with 1-MT than that in normal control mice.Furthemore,in the mice that were administered 1-MT plus DC vaccine,the tumor was increased more slowly than in mice treated with DC vaccine or 1-MT alone,or PBS on day 36(P<0.01).Our results indicated that 1-MT may enhance anti-tumor efficacy of dendritic cells pulsed with tumor cell lysate by downregulating the percentage of Tregs.
基金The authors gratefully acknowledge the financial supports from the National Natural Science Foundation of China （Grant Nos. 51078054, 51108120, and 51178139） and the National Creative Research Group from the National Natural Science Foundation of China （No. 51121062）.
文摘A mulfistep conversion system composed of phenol hydroxylase （PHrND） and 2,3-dihydroxy-biphenyl 1,2-dioxygenase （BphCLA_4） was used to synthesize methylcatechols and semialdehydes from o- and m-cresol for the first time. Docking studies displayed by PyMOL predicted that cresols and methylcatechols could be theoretically transformed by this multistep conversion system~ High performance liquid chromatography mass spectrometry （HPLC-MS） analysis also indicated that the products formed from multistep conversion were the corresponding 3-methylcatechol, 4-methylcatechol, 2- hydroxy-3-methyl-6-oxohexa-2,4-dienoic acid （2- hydroxy-3-methyl-ODA） and 2-hydroxy-5-methyl-6-oxo- hexa-2,4-dienoic acid （2-hydroxy-5-methyl-ODA）. The optimal cell concentrations of the recombinant E. coli strain BL21 （DE3） expressing phenol hydroxylase （PHrND） and 2,3-dihydroxy-biphenyl 1,2-dioxygenase （BphCLA_4） and pH for the multistep conversion of o- and m-cresol were 4.0 （g-L-1 cell dry weight） and pH 8.0, respectively. For the first step conversion, the formation rate of 3- methylcatechol （0.29μmol·L-1·min-1·mg-1cell dry weight） from o-cresol was similarly with that ofmethylca- techols （0.28 μmol·L-1·min-1·mg-1 cell dry weight） from m-cresol by strain PHrND. For the second step conversion, strain BphCLA_4 showed higher formation rate （0.83 μmol·L-1·min-1·mg-1 cell dry weight） for 2-hydroxy-3-methyl- ODA and 2-hydroxy-5-methyl-ODA from m-cresol, which was 1.1-fold higher than that for 2-hydroxy-3-methyl- ODA （0.77 μmol·L-1·min-1·mg-1. mglcell dry weight） from ocresol. The present study suggested the potential application of the multistep conversion system for the production of chemical synthons and high-value products.
基金support from the National Natural Science Foundation of China(Nos.81773648 and 81973267)the Zhejiang Provincial Natural Science Foundation of China(Nos.LD19H300001 and LQ20H300004).
文摘Researches on indoleamine-2,3-dioxygenase-1(IDO1),a neoplastic pathogenesis-related protein,have provided a new angle of view to regulate malignancy-related immunosuppression.However,the therapeutic efficacy of IDO1 inhibitors is subject to key limitations as both cancer and dendritic cells tend to be trapped in the IDO1-mediated immune dysfunction,which poses challenges to the inhibitory potency of drug regimens in multiple targets.Here,we report on the fabrication technique of a biomimetic nanocarrier that is endowed with the whole array of cancer cell membrane proteins for encapsulating the most used IDO1 probe indoximod(IND).By fully utilizing the homologous adhesion proteins and antigenic motifs on cytomembrane,these nanoparticulate particles are capable of infiltrating tumors and actively accumulating in cancer and dendritic cells,as well as hitching a ride on dendritic cells to tumor-draining lymph nodes.Ultimately,by increasing the distribution of drugs in both tumor cells and dendritic cells in tumor-draining lymph nodes,these formulations greatly enhance the efficacy of IND without the aid of chemotherapeutic drugs,achieving substantial control of tumor growth.Overall,this leverage of bionanotechnology maximizes the therapeutic potential of IND and can provide a theoretical reference for the clinical application of IDO1 inhibitors.
基金This research was supported by the National Natural Science Foundation of China(51703178,51903203,81770728)the China Postdoctoral Science Foundation(2019M663742,2019M653661)Natural Science Foundation of Zhejiang Province(LWY20H180002).
文摘Combining chemo-therapeutics with immune checkpoint inhibitors facilitates killing cancer cells and activating the immune system through inhibiting immune escape.However,their treatment effects remain limited due to the compromised accumulation of both drugs and inhibitors in certain tumor tissues.Herein,a new poly(acrylamide-co-acrylonitrile-co-vinylimidazole-co-bis(2-methacryloyl)oxyethyl disulfide)(PAAVB)polymer-based intelligent platform with controllable upper critical solution temperature(UCST)was used for the simultaneous delivery of paclitaxel(PTX)and curcumin(CUR).Additionally,a hyaluronic acid(HA)layer was coated on the surface of PAAVB NPs to target the CD44-overexpressed tumor cells.The proposed nanomedicine demonstrated a gratifying accumulation in tumor tissue and uptake by cancer cells.Then,the acidic microenvironment and high level of glutathione(GSH)in cancer cells could spontaneously decrease the UCST of polymer,leading to the disassembly of the NPs and rapid drug release at body temperature without extra-stimuli.Significantly,the released PTX and CUR could induce the immunogenic cell death(ICD)to promote adaptive anti-tumor immunogenicity and inhibit immunosuppression through suppressing the activity of indoleamine 2,3-dioxygenase 1(IDO1)enzyme respectively.Therefore,the synergism of this intelligent nanomedicine can suppress primary breast tumor growth and inhibit their lung metastasis.
