Currently different Toll-like receptor (TLR) agonists are tested in humans for their ability to enhance the efficacy of specific immunotherapy (SIT). Recent clinical data suggest that this may be achieved by increasin...Currently different Toll-like receptor (TLR) agonists are tested in humans for their ability to enhance the efficacy of specific immunotherapy (SIT). Recent clinical data suggest that this may be achieved by increasing allergen-specific Th1 responses. However, it is not clear which TLR agonist is best suited to be used in combination with SIT. We tested the ability of five TLR agonists, LTA, poly(I:C), LPS, R848, and CpG-ODN, activating TLR2, 3, 4, 7, and 9, to induce allergen-specific Th1 and suppress allergen-specific Th2 responses in a preclinical setting. Mice were immunized by intraperitoneal injection of ovalbumin (OVA)/Al(OH)3 together with different doses (0.0025, 0.025, 0.25, and 2.5 mg/kg) of agonists followed by two OVA aerosol challenges. The results of these experiments showed, that the suppression of allergen-specific Th2 responses and the induction of Th1 responses dependedon the dose and the agonists used. All TLR agonists increased allergen-specific IgG2a, and with the exception of poly(I:C), reduced allergen-specific IgE levels in the serum. Allergic cutaneous anaphylaxis was also suppressed in mice when LPS or CpG was given together with OVA/alum. The strongest Th1 responses were induced by CpG and poly(I:C), characterized by the presence of IFN-g in the BAL and the highest OVA-specific IgG2a levels in the serum. This study suggests that the TLR9 agonist CpG-ODN and TLR4 agonist LPS have the strongest suppressive effects on the development of aller-gen-specific Th2 responses in mice and CpG-ODN induces the strongest allergen-specific Th1 responses. Therefore these two TLR agonists may be good candidates to combine with allergen in novel SIT formulations in humans.展开更多
Objective:CAR-T/NK cells have had limited success in the treatment of solid tumors,such as colorectal cancer(CRC),in part because of the heterogeneous nature of tumor-associated antigens that lead to antigen-negative ...Objective:CAR-T/NK cells have had limited success in the treatment of solid tumors,such as colorectal cancer(CRC),in part because of the heterogeneous nature of tumor-associated antigens that lead to antigen-negative relapse after the initial response.This barrier might be overcome by enhancing the recruitment and durability of endogenous immune cells.Methods:Immunohistochemistry and flow cytometry were used to assess the expression of CD133 antigen in tissue microarrays and cell lines,respectively.Retroviral vector transduction was used to generate CBLB502-secreting CAR133-NK92 cells(CAR133-i502-NK92).The tumor killing capacity of CAR133-NK92 cells in vitro and in vivo were quantified via LDH release,the RTCA assay,and the degranulation test,as well as measuring tumor bioluminescence signal intensity in mice xenografts.Results:We engineered CAR133-i502-NK92 cells and demonstrated that those cells displayed enhanced proliferation(9.0×10^(4)cells vs.7.0×10^(4)cells)and specific anti-tumor activities in vitro and in a xenogeneic mouse model,and were well-tolerated.Notably,CBLB502 secreted by CAR133-i502-NK92 cells effectively activated endogenous immune cells.Furthermore,in hCD133+/hCD133−mixed cancer xenograft models,CAR133-i502-NK92 cells suppressed cancer growth better than the counterparts(n=5,P=0.0297).Greater T-cell infiltration was associated with greater anti-tumor potency(P<0.0001).Conclusions:Armed with a CBLB502 TLR5 agonist,CAR133-NK92 cells were shown to be capable of specifically eliminating CD133-positive colon cancer cells in a CAR133-dependent manner and indirectly eradicating CD133-negative colon cancer cells in a CBLB502-specific endogenous immune response manner.This study describes a novel technique for optimizing CAR-T/NK cells for the treatment of antigenically-diverse solid tumors.展开更多
Toll-like receptor(TLR)agonists,as promising adjuvants and immunotherapeutic agents,have the potential to enhance immune responses and modulate antigen-dependent T-cell immune memory through activation of distinct sig...Toll-like receptor(TLR)agonists,as promising adjuvants and immunotherapeutic agents,have the potential to enhance immune responses and modulate antigen-dependent T-cell immune memory through activation of distinct signaling pathways.However,their clinical application is hindered by uncontrolled systemic inflammatory reactions.Therefore,it is imperative to create a vaccine adjuvant for TLR receptors that ensures both safety and efficacy.In this study,we designed lymph node-targeted cholesterolized TLR7 agonist cationic liposomes(1V209-Cho-Lip^(+))to mitigate undesired side effects.Co-delivery of the model antigen OVA and cholesterolized TLR7 agonist facilitated DC maturation through TLR activation while ensuring optimal presentation of the antigen to CD8^(+)T cells.The main aim of the present study is to evaluate the adjuvant effectiveness of 1V209-Cho-Lip^(+)in tumor vaccines.Following immunization with 1V209-Cho-Lip^(+)+OVA,we observed a pronounced"depot effect"and enhanced trafficking to secondary lymphoid organs.Prophylactic vaccination with 1V209-Cho-Lip^(+)^(+)OVA significantly delays tumor development,prolongs mouse survival,and establishes durable immunity against tumor recurrence.Additionally,1V209-Cho-Lip^(+)+OVA,while used therapeutic tumor vaccine,has demonstrated its efficacy in inhibiting tumor progression,and when combined with anti-PD-1,it further enhances antitumor effects.Therefore,the co-delivery of antigen and lymph node-targeted cholesterolized TLR7 agonist shows great promise as a cancer vaccine.展开更多
Toll-like receptors(TLRs)are a family of highly conserved germline-encoded pattern-recognition receptors that are essential for host immune responses.TLR ligands represent a promising class of immunotherapeutics or va...Toll-like receptors(TLRs)are a family of highly conserved germline-encoded pattern-recognition receptors that are essential for host immune responses.TLR ligands represent a promising class of immunotherapeutics or vaccine adjuvants with the potential to generate an effective antitumor immune response.The TLR7/8 agonists have aroused interest because they not only activate antigen-presenting cells but also promote activation of T and natural killer(NK)cells.However,the exact mechanism by which stimulation of these TLRs promotes immune responses remains unclear,and different TLR7/8 agonists have been found to induce different responses.In this study,we demonstrate that both gardiquimod and imiquimod promote the proliferation of murine splenocytes,stimulate the activation of splenic T,NK and natural killer T(NKT)cells,increase the cytolytic activity of splenocytes against B16 and MCA-38 tumor cell lines,and enhance the expression of costimulatory molecules and IL-12 by macrophages and bone marrow-derived dendritic cells(DCs).In a murine model,both agonists improved the antitumor effects of tumor lysate-loaded DCs,resulting in delayed growth of subcutaneous B16 melanoma tumors and suppression of pulmonary metastasis.Further,we found that gardiquimod demonstrated more potent antitumor activity than imiquimod.These results suggest that TLR7/8 agonists may serve as potent innate and adaptive immune response modifiers in tumor therapy.More importantly,they can be used as vaccine adjuvants to potentiate the efficiency of DC-based tumor immunotherapy.展开更多
Radiofrequency ablation(RFA)is the most common approach to thermal ablation for cancer therapy.Unfortunately,its efficacy is limited by incomplete ablation,and further optimization of RFA is required.Here,we demonstra...Radiofrequency ablation(RFA)is the most common approach to thermal ablation for cancer therapy.Unfortunately,its efficacy is limited by incomplete ablation,and further optimization of RFA is required.Here,we demonstrate that incubation at 65°C triggers more EG7 tumor cell death by necrosis than treatment at 45°C,and the 65°C-treated cells are more effective at inducing antigen-specific CD8^(+)cytotoxic T lymphocyte(CTL)responses after injection in mice than the 45°C-treated ones.Dendritic cells(DCs)that phagocytose 65°C-treated EG7 cells become mature with upregulated MHCII and CD80 expression and are capable of efficiently inducing effector CTLs in mouse tumor models.RFA(65°C)therapy of EG7 tumors induces large areas of tumor necrosis and stimulates CTL responses.This leads to complete regression of small(~100 mm^(3))tumors but fails to suppress the growth of larger(~350 mm^(3))tumors.The administration of the Toll-like receptor-9(TLR9)agonist unmethylated cytosine-phosphorothioate-guanine oligonucleotide(CpG)to DCs phagocytosing 65°C-treated EG7 cells enhances the expression of MHCII and CD40 on DCs as well as DC-induced stimulation of CTL responses.Importantly,the intratumoral administration of CpG following RFA also increases the frequencies of tumor-associated immunogenic CD11b−CD11c^(+)CD103^(+)DC2 and CD11b+F4/80+MHCII+M1 macrophages and increases CD4^(+)and CD8^(+)T-cell tumor infiltration,leading to enhanced CD4^(+)T cell-dependent CTL responses and potent inhibition of primary RFA-treated or distant untreated tumor growth as well as tumor lung metastasis in mice bearing larger tumors.Overall,our data indicate that CpG administration,which enhances RFA-induced CTL responses and ultimately potentiates the inhibition of primary tumor growth and lung metastasis,is a promising strategy for improving RFA treatment,which may assist in optimizing this important cancer therapy.展开更多
Objective:Cancer stem cell is one of the important causes of tumorigenesis as well as a drug target in the treatment of malignant tumor.However,at present,there is no immune vaccine targeting these cells.Octamer-bindi...Objective:Cancer stem cell is one of the important causes of tumorigenesis as well as a drug target in the treatment of malignant tumor.However,at present,there is no immune vaccine targeting these cells.Octamer-binding transcription factor 4(OCT4),a marker of embryonic stem cells and germ cells,often highly expresses in the early stages of tumorigenesis and is therefore a good candidate for cancer vaccine development.Methods:To identify the optimal carrier and adjuvant combination,we chemically synthesized and linked three different OCT4 epitope antigens to a carrier protein,keyhole limpet hemocyanin(KLH),combined with Toll-like receptor 9 agonist(TLR9).Results:Immunization with OCT4-3+TLR9 produced the strongest immune response in mice.In prevention assays,significant tumor growth inhibition was achieved in BABL/c mice treated with OCT4-3+TLR9(P<0.01).Importantly,the results showed that cytotoxic T lymphocyte activity and the inhibition of tumor growth were enhanced in mice immunized with OCT4-3 combined with TLR9.Meanwhile,multiple cytokines[such as interferon(IFN)-γ(P<0.05),interleukin(IL)-12(P<0.05),IL-2(P<0.01),and IL-6(P<0.05)]promoting cellular immune responses were shown to be greatly enhanced in mice immunized with OCT4-3+TLR9.Moreover,we considered safety considerations in terms of the composition of the vaccines to help facilitate the development of effective next-generation vaccines.Conclusions:Collectively,these experiments demonstrated that combination therapy with TLR9 agonist induced a tumor-specific adaptive immune response,leading to the suppression of primary tumor growth in testis embryonic carcinoma.展开更多
Cancer vaccination holds great promise for cancer treatment,but its effectiveness is hindered by suboptimal activation of CD8+cytotoxic T lymphocytes,which are potent effectors to mediate anti-tumor immune responses.A...Cancer vaccination holds great promise for cancer treatment,but its effectiveness is hindered by suboptimal activation of CD8+cytotoxic T lymphocytes,which are potent effectors to mediate anti-tumor immune responses.A possible solution is to switch antigen-presenting cells to present tumor antigens via the major histocompatibility complex class I(MHC-I)to CD8+T cells-a process known as cross-presentation.To achieve this goal,we develop a three-dimensional(3D)scaffold vaccine to promote antigen cross-presentation by persisted toll-like receptor-2(TLR2)activation after one injection.This vaccine comprises polysaccharide frameworks that“hook”TLR2 agonist(acGM)via tunable hydrophobic interactions and forms a 3D macroporous scaffold via click chemistry upon subcutaneous injection.Its retention-and-release of acGM enables sustained TLR2 activation in abundantly recruited dendritic cells in situ,inducing intracellular production of reactive oxygen species(ROS)in optimal kinetics that crucially promotes efficient antigen cross-presentation.The scaffold loaded with model antigen ovalbumin(OVA)or tumor specific antigen can generate potent immune responses against lung metastasis in B16-OVA-innoculated wild-type mice or spontaneous colorectal cancer in transgenic ApcMin/+mice,respectively.Notably,it requires neither additional adjuvants nor external stimulation to function and can be adjusted to accommodate different antigens.The developed scaffold vaccine may represent a new,competent tool for next-generation personalized cancer vaccination.展开更多
For cancer immunotherapy,triggering toll-like receptors(TLRs)in dendritic cells(DCs)can potentiate antigen-based immune responses.Nevertheless,to generate robust and long-lived immune responses,a well-designed nanovac...For cancer immunotherapy,triggering toll-like receptors(TLRs)in dendritic cells(DCs)can potentiate antigen-based immune responses.Nevertheless,to generate robust and long-lived immune responses,a well-designed nanovaccine should consider different locations of TLRs on DCs and co-deliver both antigens and TLR agonist combinations to synergistically induce optimal antitumor immunity.Herein,we fabricated lipid-polymer hybrid nanoparticles(LPNPs)to spatio-temporally deliver model antigen ovalbumin(OVA)on the surface of the lipid layer,TLR4 agonist monophosphoryl lipid A(MPLA)within the lipid layer,and TLR7 agonist imiquimod(IMQ)in the polymer core to synergistically activate DCs by both extra-and intra-cellular TLRs for enhancing adaptive immune responses.LPNPs-based nanovaccines exhibited a narrow size distribution at the mean diameter of 133.23 nm and zeta potential of−2.36 mV,showed a high OVA loading(around 70.83μg/mg)and IMQ encapsulation efficiency(88.04%).Our data revealed that LPNPs-based nanovaccines showed great biocompatibility to immune cells and an excellent ability to enhance antigen internalization,thereby promoting DCs maturation and cytokines production.Compared to Free OVA,OVA-LPNPs promoted antigen uptake,lysosome escape,depot effect and migration to secondary lymphatic organs.In vivo immunization showed that IMQ-MPLA-OVA-LPNPs with dual agonists induced more powerful cellular and humoral immune responses.Moreover,prophylactic vaccination by IMQ-MPLA-OVA-LPNPs effectively suppressed tumor growth and increased survival efficacy.Hence,the nanovaccines we fabricated can effectively co-deliver antigens and different TLR agonists and realize coordinated stimulation of DCs in a spatio-temporal manner for enhanced immune responses,which provides a promising strategy for cancer immunotherapy.展开更多
In the tumor immunosuppressive microenvironment(TIME),antigen presenting cells(APCs)usually exhibit a tumor suppressor phenotype.Toll-like receptors(TLRs)agonists could reprogram M2-type macrophages to M1-type and sti...In the tumor immunosuppressive microenvironment(TIME),antigen presenting cells(APCs)usually exhibit a tumor suppressor phenotype.Toll-like receptors(TLRs)agonists could reprogram M2-type macrophages to M1-type and stimulate dendritic cells(DCs)maturation.The combination of TLR7/8 and TLR9 agonists seems to have synergistic therapeutic efficacy.Here,we designed a lipid-coated mesoporous silica nanoparticle(MSNs@Lipo)for the co-delivery of TLR7/8 agonist resiquimod(R848)and TLR9 agonist CpG oligodeoxynucleotides(ODNs)(CpG@MSNs-R@L-M).R848 was firstly conjugated onto the nanoparticle via silane chemistry,which is acidic responsive drug release.Then,CpG was loaded onto the nanoparticle through the positive charge mainly from TLR7/8 agonist R848.Our in vitro experiments further indicated that both drugs have acid-responsive release properties and could be taken up by DCs and located on the endosomes of APCs.More importantly,CpG@MSNs-R@L-M could significantly improve the antitumor efficacy in B16F10 melanoma model.The mechanistic study demonstrated that CpG@MSNsR@L-M could remarkably modulate the TIME by promoting the maturation of DCs and repolarizing macrophages from M2 to M1 phenotype and facilitating the infiltration of tumor cytotoxic T cells.It was concluded that in comparison to single agonist,the codelivery of dual agonists,CpG and R848,can improve anti-tumor immune responses for cancer immunotherapy.展开更多
Due to the heterogeneity of tumors,single phototherapy cannot completely ablate tumors and inhibit tumor metastasis.To overcome these,we formulated targeted and multifunctional polymersomes ABC@ICGIMQ-LHRH(AIRL)that e...Due to the heterogeneity of tumors,single phototherapy cannot completely ablate tumors and inhibit tumor metastasis.To overcome these,we formulated targeted and multifunctional polymersomes ABC@ICGIMQ-LHRH(AIRL)that encapsulated Toll-like receptor(TLR)7/8 agonist imiquimod(IMQ)and photosensitizer indocyanine green(ICG)in the hydrophobic layer as well as bubble-generator NH_(4)HCO_(3) in the hydrophilic cavity to inhibit the growth of primary and distant tumors,and prevent tumor metastasis through synergistic photoimmunotherapy.The AIRL polymersomes exhibited uniform and stable size,and high drug encapsulation efficiency,acid/reduction/laser responsiveness,excellent photothermal conversion efficiency,effective reactive oxygen species generation,high tumor accumulation.AIRL could be effectively internalized by dendritic cells(DCs),achieve lysosome escape and enhance DCs maturation.The synergistic photoimmunotherapy via AIRL polymersomes remarkably promoted the differentiation and activation of T cells,elevated strong systemic immune response to eradicate primary tumors and inhibit the growth of distant tumors.Simultaneously,the endurable immunological memory prevented tumor metastasis,which provided a promising nanoplatform for the combination therapy of cancer.展开更多
佐剂(adjuvant)是增强和调节疫苗抗原免疫反应的增强剂,与抗原一起使用能使机体产生更强或更平衡的免疫反应。近年来,重组蛋白疫苗、核酸疫苗等新型疫苗是疫苗的研发热点,尤其是重组蛋白疫苗,通常存在免疫原性弱或辅助性T细胞(helper T ...佐剂(adjuvant)是增强和调节疫苗抗原免疫反应的增强剂,与抗原一起使用能使机体产生更强或更平衡的免疫反应。近年来,重组蛋白疫苗、核酸疫苗等新型疫苗是疫苗的研发热点,尤其是重组蛋白疫苗,通常存在免疫原性弱或辅助性T细胞(helper T cells,Th)1/Th2免疫反应不平衡等问题,需要添加佐剂以改善疫苗的免疫效果,因而佐剂开发就成为该类疫苗研发的焦点之一。疫苗佐剂种类繁多且机制复杂,主要分为递送类佐剂、免疫激动剂及复合佐剂等。现就已获批的人用疫苗佐剂以及具有潜力的部分新型佐剂从其作用机制和临床或临床前应用等方面作一概述,为人用疫苗佐剂的相关研究提供理论和应用参考。展开更多
文摘Currently different Toll-like receptor (TLR) agonists are tested in humans for their ability to enhance the efficacy of specific immunotherapy (SIT). Recent clinical data suggest that this may be achieved by increasing allergen-specific Th1 responses. However, it is not clear which TLR agonist is best suited to be used in combination with SIT. We tested the ability of five TLR agonists, LTA, poly(I:C), LPS, R848, and CpG-ODN, activating TLR2, 3, 4, 7, and 9, to induce allergen-specific Th1 and suppress allergen-specific Th2 responses in a preclinical setting. Mice were immunized by intraperitoneal injection of ovalbumin (OVA)/Al(OH)3 together with different doses (0.0025, 0.025, 0.25, and 2.5 mg/kg) of agonists followed by two OVA aerosol challenges. The results of these experiments showed, that the suppression of allergen-specific Th2 responses and the induction of Th1 responses dependedon the dose and the agonists used. All TLR agonists increased allergen-specific IgG2a, and with the exception of poly(I:C), reduced allergen-specific IgE levels in the serum. Allergic cutaneous anaphylaxis was also suppressed in mice when LPS or CpG was given together with OVA/alum. The strongest Th1 responses were induced by CpG and poly(I:C), characterized by the presence of IFN-g in the BAL and the highest OVA-specific IgG2a levels in the serum. This study suggests that the TLR9 agonist CpG-ODN and TLR4 agonist LPS have the strongest suppressive effects on the development of aller-gen-specific Th2 responses in mice and CpG-ODN induces the strongest allergen-specific Th1 responses. Therefore these two TLR agonists may be good candidates to combine with allergen in novel SIT formulations in humans.
基金supported by the Technology Innovation and Application Developnent Key Program of Chongqing(Grant No.CSTC2021jscx-gksb-N0026)the National Natural Science Foundation of China(Grant No.31540016)+1 种基金the Basic Research and Frontier Exploration Projects of Chongqing(Grant No.cstc2018jcyjAX0075)the Subsidy Fund for the Development of National Silk in Chongqing(Grant No.CQ2018JSCE05).
文摘Objective:CAR-T/NK cells have had limited success in the treatment of solid tumors,such as colorectal cancer(CRC),in part because of the heterogeneous nature of tumor-associated antigens that lead to antigen-negative relapse after the initial response.This barrier might be overcome by enhancing the recruitment and durability of endogenous immune cells.Methods:Immunohistochemistry and flow cytometry were used to assess the expression of CD133 antigen in tissue microarrays and cell lines,respectively.Retroviral vector transduction was used to generate CBLB502-secreting CAR133-NK92 cells(CAR133-i502-NK92).The tumor killing capacity of CAR133-NK92 cells in vitro and in vivo were quantified via LDH release,the RTCA assay,and the degranulation test,as well as measuring tumor bioluminescence signal intensity in mice xenografts.Results:We engineered CAR133-i502-NK92 cells and demonstrated that those cells displayed enhanced proliferation(9.0×10^(4)cells vs.7.0×10^(4)cells)and specific anti-tumor activities in vitro and in a xenogeneic mouse model,and were well-tolerated.Notably,CBLB502 secreted by CAR133-i502-NK92 cells effectively activated endogenous immune cells.Furthermore,in hCD133+/hCD133−mixed cancer xenograft models,CAR133-i502-NK92 cells suppressed cancer growth better than the counterparts(n=5,P=0.0297).Greater T-cell infiltration was associated with greater anti-tumor potency(P<0.0001).Conclusions:Armed with a CBLB502 TLR5 agonist,CAR133-NK92 cells were shown to be capable of specifically eliminating CD133-positive colon cancer cells in a CAR133-dependent manner and indirectly eradicating CD133-negative colon cancer cells in a CBLB502-specific endogenous immune response manner.This study describes a novel technique for optimizing CAR-T/NK cells for the treatment of antigenically-diverse solid tumors.
基金supported by the National Science Foundation for Excellent Young Scholars(32122052,China)National Natural Science Foundation Regional Innovation and Development(No.U19A2003,China).
文摘Toll-like receptor(TLR)agonists,as promising adjuvants and immunotherapeutic agents,have the potential to enhance immune responses and modulate antigen-dependent T-cell immune memory through activation of distinct signaling pathways.However,their clinical application is hindered by uncontrolled systemic inflammatory reactions.Therefore,it is imperative to create a vaccine adjuvant for TLR receptors that ensures both safety and efficacy.In this study,we designed lymph node-targeted cholesterolized TLR7 agonist cationic liposomes(1V209-Cho-Lip^(+))to mitigate undesired side effects.Co-delivery of the model antigen OVA and cholesterolized TLR7 agonist facilitated DC maturation through TLR activation while ensuring optimal presentation of the antigen to CD8^(+)T cells.The main aim of the present study is to evaluate the adjuvant effectiveness of 1V209-Cho-Lip^(+)in tumor vaccines.Following immunization with 1V209-Cho-Lip^(+)+OVA,we observed a pronounced"depot effect"and enhanced trafficking to secondary lymphoid organs.Prophylactic vaccination with 1V209-Cho-Lip^(+)^(+)OVA significantly delays tumor development,prolongs mouse survival,and establishes durable immunity against tumor recurrence.Additionally,1V209-Cho-Lip^(+)+OVA,while used therapeutic tumor vaccine,has demonstrated its efficacy in inhibiting tumor progression,and when combined with anti-PD-1,it further enhances antitumor effects.Therefore,the co-delivery of antigen and lymph node-targeted cholesterolized TLR7 agonist shows great promise as a cancer vaccine.
基金supported by grants from the Natural Science Foundation of China(no.90713033)the National 973 Basic Research Program of China(no.2007CB815800)the National 115 Key Project for HBV Research(no.2008ZX10002-008).
文摘Toll-like receptors(TLRs)are a family of highly conserved germline-encoded pattern-recognition receptors that are essential for host immune responses.TLR ligands represent a promising class of immunotherapeutics or vaccine adjuvants with the potential to generate an effective antitumor immune response.The TLR7/8 agonists have aroused interest because they not only activate antigen-presenting cells but also promote activation of T and natural killer(NK)cells.However,the exact mechanism by which stimulation of these TLRs promotes immune responses remains unclear,and different TLR7/8 agonists have been found to induce different responses.In this study,we demonstrate that both gardiquimod and imiquimod promote the proliferation of murine splenocytes,stimulate the activation of splenic T,NK and natural killer T(NKT)cells,increase the cytolytic activity of splenocytes against B16 and MCA-38 tumor cell lines,and enhance the expression of costimulatory molecules and IL-12 by macrophages and bone marrow-derived dendritic cells(DCs).In a murine model,both agonists improved the antitumor effects of tumor lysate-loaded DCs,resulting in delayed growth of subcutaneous B16 melanoma tumors and suppression of pulmonary metastasis.Further,we found that gardiquimod demonstrated more potent antitumor activity than imiquimod.These results suggest that TLR7/8 agonists may serve as potent innate and adaptive immune response modifiers in tumor therapy.More importantly,they can be used as vaccine adjuvants to potentiate the efficiency of DC-based tumor immunotherapy.
基金supported by grants from CoMRAD(#417578)College of Medicine,University of Saskatchewan,Prostate Cancer Fight Foundation(#417782)+1 种基金Royal University Hospital Research Foundation(#417450)Saskatchewan Health Research Foundation(#418672).
文摘Radiofrequency ablation(RFA)is the most common approach to thermal ablation for cancer therapy.Unfortunately,its efficacy is limited by incomplete ablation,and further optimization of RFA is required.Here,we demonstrate that incubation at 65°C triggers more EG7 tumor cell death by necrosis than treatment at 45°C,and the 65°C-treated cells are more effective at inducing antigen-specific CD8^(+)cytotoxic T lymphocyte(CTL)responses after injection in mice than the 45°C-treated ones.Dendritic cells(DCs)that phagocytose 65°C-treated EG7 cells become mature with upregulated MHCII and CD80 expression and are capable of efficiently inducing effector CTLs in mouse tumor models.RFA(65°C)therapy of EG7 tumors induces large areas of tumor necrosis and stimulates CTL responses.This leads to complete regression of small(~100 mm^(3))tumors but fails to suppress the growth of larger(~350 mm^(3))tumors.The administration of the Toll-like receptor-9(TLR9)agonist unmethylated cytosine-phosphorothioate-guanine oligonucleotide(CpG)to DCs phagocytosing 65°C-treated EG7 cells enhances the expression of MHCII and CD40 on DCs as well as DC-induced stimulation of CTL responses.Importantly,the intratumoral administration of CpG following RFA also increases the frequencies of tumor-associated immunogenic CD11b−CD11c^(+)CD103^(+)DC2 and CD11b+F4/80+MHCII+M1 macrophages and increases CD4^(+)and CD8^(+)T-cell tumor infiltration,leading to enhanced CD4^(+)T cell-dependent CTL responses and potent inhibition of primary RFA-treated or distant untreated tumor growth as well as tumor lung metastasis in mice bearing larger tumors.Overall,our data indicate that CpG administration,which enhances RFA-induced CTL responses and ultimately potentiates the inhibition of primary tumor growth and lung metastasis,is a promising strategy for improving RFA treatment,which may assist in optimizing this important cancer therapy.
基金supported by the National Natural Science Foundation of China(NSFC)(Grant Nos.81803081,81703050,and 21677102)Shenzhen Basic Research Project(Grant Nos.JCYJ20170303160906960,JCYJ20170307100703967,and JCYJ20160331114230843)+2 种基金the Shenzhen International Cooperation Research Project(Grant No.GJHZ20170313111237888)the Subject Layout Project of Shenzhen Science and Technology Creation Commission(Grant Nos.JCYJ20170818092553608 and JCYJ20160331114230843)the China Shenzhen Peacock Innovation Team Project(Grant No.KQTD20140630100658078)。
文摘Objective:Cancer stem cell is one of the important causes of tumorigenesis as well as a drug target in the treatment of malignant tumor.However,at present,there is no immune vaccine targeting these cells.Octamer-binding transcription factor 4(OCT4),a marker of embryonic stem cells and germ cells,often highly expresses in the early stages of tumorigenesis and is therefore a good candidate for cancer vaccine development.Methods:To identify the optimal carrier and adjuvant combination,we chemically synthesized and linked three different OCT4 epitope antigens to a carrier protein,keyhole limpet hemocyanin(KLH),combined with Toll-like receptor 9 agonist(TLR9).Results:Immunization with OCT4-3+TLR9 produced the strongest immune response in mice.In prevention assays,significant tumor growth inhibition was achieved in BABL/c mice treated with OCT4-3+TLR9(P<0.01).Importantly,the results showed that cytotoxic T lymphocyte activity and the inhibition of tumor growth were enhanced in mice immunized with OCT4-3 combined with TLR9.Meanwhile,multiple cytokines[such as interferon(IFN)-γ(P<0.05),interleukin(IL)-12(P<0.05),IL-2(P<0.01),and IL-6(P<0.05)]promoting cellular immune responses were shown to be greatly enhanced in mice immunized with OCT4-3+TLR9.Moreover,we considered safety considerations in terms of the composition of the vaccines to help facilitate the development of effective next-generation vaccines.Conclusions:Collectively,these experiments demonstrated that combination therapy with TLR9 agonist induced a tumor-specific adaptive immune response,leading to the suppression of primary tumor growth in testis embryonic carcinoma.
基金supported by the Science and Technology Development Fund,Macao SAR (FDCT,No.0001/2021/AKP,0024/2023/AFJ,0060/2020/AGJ,and 005/2023/SKL)the National Natural Science Foundation of China (NSFC,No.31961160701,32022088,31971309,32001069,32230056,and 32000936)+2 种基金the Natural Science Foundation of Jiangsu Province (BK20200318)the University of Macao (MYRG-GRG2023-00136-ICMS-UMDF and MYRG2022-00100-ICMS)support from the project CICECO-Aveiro Institute of Materials,UIDB/50011/2020,UIDP/50011/2020&LA/P/0006/2020,financed by national funds through the FCT/MEC (PIDDAC).
文摘Cancer vaccination holds great promise for cancer treatment,but its effectiveness is hindered by suboptimal activation of CD8+cytotoxic T lymphocytes,which are potent effectors to mediate anti-tumor immune responses.A possible solution is to switch antigen-presenting cells to present tumor antigens via the major histocompatibility complex class I(MHC-I)to CD8+T cells-a process known as cross-presentation.To achieve this goal,we develop a three-dimensional(3D)scaffold vaccine to promote antigen cross-presentation by persisted toll-like receptor-2(TLR2)activation after one injection.This vaccine comprises polysaccharide frameworks that“hook”TLR2 agonist(acGM)via tunable hydrophobic interactions and forms a 3D macroporous scaffold via click chemistry upon subcutaneous injection.Its retention-and-release of acGM enables sustained TLR2 activation in abundantly recruited dendritic cells in situ,inducing intracellular production of reactive oxygen species(ROS)in optimal kinetics that crucially promotes efficient antigen cross-presentation.The scaffold loaded with model antigen ovalbumin(OVA)or tumor specific antigen can generate potent immune responses against lung metastasis in B16-OVA-innoculated wild-type mice or spontaneous colorectal cancer in transgenic ApcMin/+mice,respectively.Notably,it requires neither additional adjuvants nor external stimulation to function and can be adjusted to accommodate different antigens.The developed scaffold vaccine may represent a new,competent tool for next-generation personalized cancer vaccination.
基金This work was financially supported by National Natural Science Foundation of China(82072059 and 82172090)CAMS Innovation Fund for Medical Sciences(CIFMS,2021-I2M-1-058,China)+1 种基金Fundamental Research Funds for the Central Universities(2019PT320028 and 2019-0831-03,China)Tianjin Municipal Natural Science Foundation(20JCYBJC00030,China).
文摘For cancer immunotherapy,triggering toll-like receptors(TLRs)in dendritic cells(DCs)can potentiate antigen-based immune responses.Nevertheless,to generate robust and long-lived immune responses,a well-designed nanovaccine should consider different locations of TLRs on DCs and co-deliver both antigens and TLR agonist combinations to synergistically induce optimal antitumor immunity.Herein,we fabricated lipid-polymer hybrid nanoparticles(LPNPs)to spatio-temporally deliver model antigen ovalbumin(OVA)on the surface of the lipid layer,TLR4 agonist monophosphoryl lipid A(MPLA)within the lipid layer,and TLR7 agonist imiquimod(IMQ)in the polymer core to synergistically activate DCs by both extra-and intra-cellular TLRs for enhancing adaptive immune responses.LPNPs-based nanovaccines exhibited a narrow size distribution at the mean diameter of 133.23 nm and zeta potential of−2.36 mV,showed a high OVA loading(around 70.83μg/mg)and IMQ encapsulation efficiency(88.04%).Our data revealed that LPNPs-based nanovaccines showed great biocompatibility to immune cells and an excellent ability to enhance antigen internalization,thereby promoting DCs maturation and cytokines production.Compared to Free OVA,OVA-LPNPs promoted antigen uptake,lysosome escape,depot effect and migration to secondary lymphatic organs.In vivo immunization showed that IMQ-MPLA-OVA-LPNPs with dual agonists induced more powerful cellular and humoral immune responses.Moreover,prophylactic vaccination by IMQ-MPLA-OVA-LPNPs effectively suppressed tumor growth and increased survival efficacy.Hence,the nanovaccines we fabricated can effectively co-deliver antigens and different TLR agonists and realize coordinated stimulation of DCs in a spatio-temporal manner for enhanced immune responses,which provides a promising strategy for cancer immunotherapy.
基金a Start-Up grant KY2060000124 and KJ2060190030 from University of Science and Technology of ChinaNational Natural Science Foundation of China(Nos.31971299,GG2065010001,GG2060190386,and 82102953)Fundamental Research Funds for the Central Universities(Nos.WK2060190101,WY2060190092,and WK9110000144).
文摘In the tumor immunosuppressive microenvironment(TIME),antigen presenting cells(APCs)usually exhibit a tumor suppressor phenotype.Toll-like receptors(TLRs)agonists could reprogram M2-type macrophages to M1-type and stimulate dendritic cells(DCs)maturation.The combination of TLR7/8 and TLR9 agonists seems to have synergistic therapeutic efficacy.Here,we designed a lipid-coated mesoporous silica nanoparticle(MSNs@Lipo)for the co-delivery of TLR7/8 agonist resiquimod(R848)and TLR9 agonist CpG oligodeoxynucleotides(ODNs)(CpG@MSNs-R@L-M).R848 was firstly conjugated onto the nanoparticle via silane chemistry,which is acidic responsive drug release.Then,CpG was loaded onto the nanoparticle through the positive charge mainly from TLR7/8 agonist R848.Our in vitro experiments further indicated that both drugs have acid-responsive release properties and could be taken up by DCs and located on the endosomes of APCs.More importantly,CpG@MSNs-R@L-M could significantly improve the antitumor efficacy in B16F10 melanoma model.The mechanistic study demonstrated that CpG@MSNsR@L-M could remarkably modulate the TIME by promoting the maturation of DCs and repolarizing macrophages from M2 to M1 phenotype and facilitating the infiltration of tumor cytotoxic T cells.It was concluded that in comparison to single agonist,the codelivery of dual agonists,CpG and R848,can improve anti-tumor immune responses for cancer immunotherapy.
基金financially supported by National Natural Science Foundation of China(Nos.82172090,82302390 and 82072059)CAMS Innovation Fund for Medical Sciences(Nos.2021-I2M-1-058 and 2022-I2M-1-023)+3 种基金China Postdoctoral Science Foundation(No.2022M720502)Tianjin Municipal Natural Science Foundation(No.22JCQNJC00070)CAMS Union Young Scholars Support Program(No.2022051)Fundamental Research Funds for the Central Universities(No.2019PT320028)。
文摘Due to the heterogeneity of tumors,single phototherapy cannot completely ablate tumors and inhibit tumor metastasis.To overcome these,we formulated targeted and multifunctional polymersomes ABC@ICGIMQ-LHRH(AIRL)that encapsulated Toll-like receptor(TLR)7/8 agonist imiquimod(IMQ)and photosensitizer indocyanine green(ICG)in the hydrophobic layer as well as bubble-generator NH_(4)HCO_(3) in the hydrophilic cavity to inhibit the growth of primary and distant tumors,and prevent tumor metastasis through synergistic photoimmunotherapy.The AIRL polymersomes exhibited uniform and stable size,and high drug encapsulation efficiency,acid/reduction/laser responsiveness,excellent photothermal conversion efficiency,effective reactive oxygen species generation,high tumor accumulation.AIRL could be effectively internalized by dendritic cells(DCs),achieve lysosome escape and enhance DCs maturation.The synergistic photoimmunotherapy via AIRL polymersomes remarkably promoted the differentiation and activation of T cells,elevated strong systemic immune response to eradicate primary tumors and inhibit the growth of distant tumors.Simultaneously,the endurable immunological memory prevented tumor metastasis,which provided a promising nanoplatform for the combination therapy of cancer.
文摘佐剂(adjuvant)是增强和调节疫苗抗原免疫反应的增强剂,与抗原一起使用能使机体产生更强或更平衡的免疫反应。近年来,重组蛋白疫苗、核酸疫苗等新型疫苗是疫苗的研发热点,尤其是重组蛋白疫苗,通常存在免疫原性弱或辅助性T细胞(helper T cells,Th)1/Th2免疫反应不平衡等问题,需要添加佐剂以改善疫苗的免疫效果,因而佐剂开发就成为该类疫苗研发的焦点之一。疫苗佐剂种类繁多且机制复杂,主要分为递送类佐剂、免疫激动剂及复合佐剂等。现就已获批的人用疫苗佐剂以及具有潜力的部分新型佐剂从其作用机制和临床或临床前应用等方面作一概述,为人用疫苗佐剂的相关研究提供理论和应用参考。
