Objective Combination immunotherapy strategies targeting OX40,a co-stimulatory molecule that can enhance antitumor immunity by modulating the proliferation,differentiation,and effector function of tumor-infiltrating T...Objective Combination immunotherapy strategies targeting OX40,a co-stimulatory molecule that can enhance antitumor immunity by modulating the proliferation,differentiation,and effector function of tumor-infiltrating T cells,have attracted much attention for their excellent therapeutic effects.In this study,we aimed to evaluate the antitumor efficacy of combined anti-OX40 and hepatitis B core viruslike particles(HBc VLPs)therapy using a mouse colon cancer model.Methods Humanized B-h OX40 mice were injected subcutaneously with MC38 colon tumor cells and treated with HBc VLPs+anti-h OX40 antibody.Tumor growth was monitored.Flow cytometric analysis was performed to evaluate the populations of T cell subsets in the tumors.Results The combination of anti-OX40 with HBc VLPs resulted in a significant delay in tumor growth,suggesting that a potent antitumor immunity was induced by the combination therapy.Further studies revealed that HBc VLPs+anti-OX40 treatment induced a significant increase in effector T cells(Teffs)and a significant decrease in regulatory T cells(Tregs)in the tumor microenvironment(TME),which accounted for the synergistic antitumor effect of anti-OX40 in combination with HBc VLPs.Conclusion Combination therapy of anti-h OX40 and HBc VLPs provides synergistic antitumor activity in colon cancer-bearing mice,which may represent a potential design strategy for cancer immunotherapy.展开更多
Early etiological diagnosis is very important for the control of sudden viral infections,and requires antibodies with both high sensitivity and high specificity.Traditional antibody preparation methods have limitation...Early etiological diagnosis is very important for the control of sudden viral infections,and requires antibodies with both high sensitivity and high specificity.Traditional antibody preparation methods have limitations,such as a long and arduous cycle,complicated operation,and high expenses.A chicken lymphoma cell line,DT40,is known to produce IgM-type antibodies and undergo gene conversion and somatic mutation in the variable region of the immunoglobulin gene during culture.Here,the DT40 cell line was developed to produce antibody libraries and prepare antibody rapidly in vitro.Since hypermutation in DT40 cells was regulated by the activation-induced cytidine deaminase(AID)gene,AID expression needs to be controlled to either fix the Ig sequence by stopping mutation or improve affinity by resuming mutation after the antibodies have been selected.In this study,we generated a novel AID-inducible DT40 cell line(DT40-H7),in which the endogenous AID gene was knocked out using the CRISPR/Cas9 genome editing system,and an inducible AID gene,based on the Tet-Off expression system,was stably transfected.AID expression was controlled in DT40-H7 cells in a simple and efficient manner;gene conversion and point mutations were observed only when AID was expressed.Using the antibody library generated from this cell line,we successfully obtained monoclonal antibodies against the NS1 protein of Zika virus.The DT40-H7 cell line represents a useful tool for the selection and evolution of antibodies and may also be a powerful tool for the rapid selection and generation of diagnostic antibodies for emerging infectious diseases.展开更多
t OX40 is a costimulatory receptor that is expressed primarily on activated CD4+,CD8+,and regulatory T cells.The ligation of OX40 to its sole ligand OX40L potentiates T cell expansion,differentiation,and activation an...t OX40 is a costimulatory receptor that is expressed primarily on activated CD4+,CD8+,and regulatory T cells.The ligation of OX40 to its sole ligand OX40L potentiates T cell expansion,differentiation,and activation and also promotes dendritic cells to mature to enhance their cytokine production.Therefore,the use of agonistic anti-Ox40 antibodies for cancer immunotherapy has gained great interest.However,most of the agonistic anti-OX40 antibodies in the clinic are OX40L-competitive and show limited efficacy.Here,we discovered that BGB-A445,a non-ligand-competitive agonistic anti-OX40 antibody currently under clinical investigation,induced optimal T cell activation without impairing dendritic cell function.In addition,BGB-A445 dose-dependently and significantly depleted regulatory T cells in vitro and in vivo via antibody-dependent cellular cytotoxicity.In the MC38 syngeneic model established in humanized OX40 knock-in mice,BGB-A445 demonstrated robust and dose-dependent antitumor efficacy,whereas the ligand-competitive anti-Ox40 antibody showed antitumor efficacy characterized by a hook effect.Furthermore,BGB-A445 demonstrated a strong combination antitumor effect with an anti-PD-1 antibody.Taken together,our findings show that BGB-A445,which does not block OX40-OX40L interaction in contrast to clinical-stage anti-OX40 antibodies,shows superior immune-stimulating effects and antitumor efficacy and thus warrants further clinical investigation.展开更多
Background: Inhibition of the lymphoma surface antigen CD40 by the antagonistic CD40 antibody NVP-HCD122 (HCD122) demonstrates activity in various lymphoma subtypes. In this preclinical in vivo study we examined the s...Background: Inhibition of the lymphoma surface antigen CD40 by the antagonistic CD40 antibody NVP-HCD122 (HCD122) demonstrates activity in various lymphoma subtypes. In this preclinical in vivo study we examined the suitability of positron emission tomography (PET) using the thymidine analogue 3’-deoxy-3’-[18F]fluorothymidine (FLT) for early response assessment upon HCD122 treatment in diffuse large B cell lymphoma (DLBCL). Methods: Immunodeficient mice bearing human DLBCL xenografts (SU-DHL-4) received weekly intraperitoneal injections of HCD122. Tumor growth was followed up until Day 14. Molecular imaging with FLT-PET was performed before (Day 0) and after start of therapy (Day 2 and Day 7). On Day 14 lymphoma xenografts were explanted for immunohistochemical analysis to correlate PET findings with CD40 surface expression on tumor tissue. Results: Treatment with HCD122 significantly delayed tumor growth resulting in a tumor growth inhibition of 45% on Day 14. Significant reduction of tumor-to-background ratio (TBR) of FLT-PET was seen in treated animals on Day 7 and preceded change of tumor volume, thus predicting therapy response to HCD122. Immunohistochemical analysis of xenografts revealed significantly higher CD40 expression on treated than on untreated tissue. Moreover, we found a significant correlation between CD40 expression and FLT-PET response for xenograft tumor treated with HCD122. Conclusions: Treatment of DLBCL with the antagonistic CD40 antibody HCD122 can be monitored with FLT-PET as early as seven days after commencement of therapy and seems to increase CD40 expression on tumor tissue.展开更多
基金supported by National Major Science and Technology Projects of China 2017ZX10105015-001-002。
文摘Objective Combination immunotherapy strategies targeting OX40,a co-stimulatory molecule that can enhance antitumor immunity by modulating the proliferation,differentiation,and effector function of tumor-infiltrating T cells,have attracted much attention for their excellent therapeutic effects.In this study,we aimed to evaluate the antitumor efficacy of combined anti-OX40 and hepatitis B core viruslike particles(HBc VLPs)therapy using a mouse colon cancer model.Methods Humanized B-h OX40 mice were injected subcutaneously with MC38 colon tumor cells and treated with HBc VLPs+anti-h OX40 antibody.Tumor growth was monitored.Flow cytometric analysis was performed to evaluate the populations of T cell subsets in the tumors.Results The combination of anti-OX40 with HBc VLPs resulted in a significant delay in tumor growth,suggesting that a potent antitumor immunity was induced by the combination therapy.Further studies revealed that HBc VLPs+anti-OX40 treatment induced a significant increase in effector T cells(Teffs)and a significant decrease in regulatory T cells(Tregs)in the tumor microenvironment(TME),which accounted for the synergistic antitumor effect of anti-OX40 in combination with HBc VLPs.Conclusion Combination therapy of anti-h OX40 and HBc VLPs provides synergistic antitumor activity in colon cancer-bearing mice,which may represent a potential design strategy for cancer immunotherapy.
基金sponsored by the Project of the National Defense Science and Technology Innovation Special Zone (to HH, 17-163-12-ZT-005-013-01)the CAMS Innovation Fund for Medical Sciences (to HH, CIFMS 2016-12 M-1-013 and to ZZ, CIFMS 2016-12 M-1-014 and 2016-12 M-3-020)+1 种基金the National Key Research and Development Program (to ZZ, 2016YFD0500300)the Fundamental Research Funds for the Central Universities (to HH, 2018PT31032)
文摘Early etiological diagnosis is very important for the control of sudden viral infections,and requires antibodies with both high sensitivity and high specificity.Traditional antibody preparation methods have limitations,such as a long and arduous cycle,complicated operation,and high expenses.A chicken lymphoma cell line,DT40,is known to produce IgM-type antibodies and undergo gene conversion and somatic mutation in the variable region of the immunoglobulin gene during culture.Here,the DT40 cell line was developed to produce antibody libraries and prepare antibody rapidly in vitro.Since hypermutation in DT40 cells was regulated by the activation-induced cytidine deaminase(AID)gene,AID expression needs to be controlled to either fix the Ig sequence by stopping mutation or improve affinity by resuming mutation after the antibodies have been selected.In this study,we generated a novel AID-inducible DT40 cell line(DT40-H7),in which the endogenous AID gene was knocked out using the CRISPR/Cas9 genome editing system,and an inducible AID gene,based on the Tet-Off expression system,was stably transfected.AID expression was controlled in DT40-H7 cells in a simple and efficient manner;gene conversion and point mutations were observed only when AID was expressed.Using the antibody library generated from this cell line,we successfully obtained monoclonal antibodies against the NS1 protein of Zika virus.The DT40-H7 cell line represents a useful tool for the selection and evolution of antibodies and may also be a powerful tool for the rapid selection and generation of diagnostic antibodies for emerging infectious diseases.
文摘t OX40 is a costimulatory receptor that is expressed primarily on activated CD4+,CD8+,and regulatory T cells.The ligation of OX40 to its sole ligand OX40L potentiates T cell expansion,differentiation,and activation and also promotes dendritic cells to mature to enhance their cytokine production.Therefore,the use of agonistic anti-Ox40 antibodies for cancer immunotherapy has gained great interest.However,most of the agonistic anti-OX40 antibodies in the clinic are OX40L-competitive and show limited efficacy.Here,we discovered that BGB-A445,a non-ligand-competitive agonistic anti-OX40 antibody currently under clinical investigation,induced optimal T cell activation without impairing dendritic cell function.In addition,BGB-A445 dose-dependently and significantly depleted regulatory T cells in vitro and in vivo via antibody-dependent cellular cytotoxicity.In the MC38 syngeneic model established in humanized OX40 knock-in mice,BGB-A445 demonstrated robust and dose-dependent antitumor efficacy,whereas the ligand-competitive anti-Ox40 antibody showed antitumor efficacy characterized by a hook effect.Furthermore,BGB-A445 demonstrated a strong combination antitumor effect with an anti-PD-1 antibody.Taken together,our findings show that BGB-A445,which does not block OX40-OX40L interaction in contrast to clinical-stage anti-OX40 antibodies,shows superior immune-stimulating effects and antitumor efficacy and thus warrants further clinical investigation.
文摘Background: Inhibition of the lymphoma surface antigen CD40 by the antagonistic CD40 antibody NVP-HCD122 (HCD122) demonstrates activity in various lymphoma subtypes. In this preclinical in vivo study we examined the suitability of positron emission tomography (PET) using the thymidine analogue 3’-deoxy-3’-[18F]fluorothymidine (FLT) for early response assessment upon HCD122 treatment in diffuse large B cell lymphoma (DLBCL). Methods: Immunodeficient mice bearing human DLBCL xenografts (SU-DHL-4) received weekly intraperitoneal injections of HCD122. Tumor growth was followed up until Day 14. Molecular imaging with FLT-PET was performed before (Day 0) and after start of therapy (Day 2 and Day 7). On Day 14 lymphoma xenografts were explanted for immunohistochemical analysis to correlate PET findings with CD40 surface expression on tumor tissue. Results: Treatment with HCD122 significantly delayed tumor growth resulting in a tumor growth inhibition of 45% on Day 14. Significant reduction of tumor-to-background ratio (TBR) of FLT-PET was seen in treated animals on Day 7 and preceded change of tumor volume, thus predicting therapy response to HCD122. Immunohistochemical analysis of xenografts revealed significantly higher CD40 expression on treated than on untreated tissue. Moreover, we found a significant correlation between CD40 expression and FLT-PET response for xenograft tumor treated with HCD122. Conclusions: Treatment of DLBCL with the antagonistic CD40 antibody HCD122 can be monitored with FLT-PET as early as seven days after commencement of therapy and seems to increase CD40 expression on tumor tissue.
