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1.
Nat Commun ; 12(1): 710, 2021 01 29.
Article in English | MEDLINE | ID: mdl-33514714

ABSTRACT

Antibody-based therapeutics have experienced a rapid growth in recent years and are now utilized in various modalities spanning from conventional antibodies, antibody-drug conjugates, bispecific antibodies to chimeric antigen receptor (CAR) T cells. Many next generation antibody therapeutics achieve enhanced potency but often increase the risk of adverse events. Antibody scaffolds capable of exhibiting inducible affinities could reduce the risk of adverse events by enabling a transient suspension of antibody activity. To demonstrate this, we develop conditionally activated, single-module CARs, in which tumor antigen recognition is directly modulated by an FDA-approved small molecule drug. The resulting CAR T cells demonstrate specific cytotoxicity of tumor cells comparable to that of traditional CARs, but the cytotoxicity is reversibly attenuated by the addition of the small molecule. The exogenous control of conditional CAR T cell activity allows continual modulation of therapeutic activity to improve the safety profile of CAR T cells across all disease indications.


Subject(s)
Antigens, Neoplasm/immunology , Immunotherapy, Adoptive/methods , Methotrexate/administration & dosage , Neoplasms/therapy , Receptors, Chimeric Antigen/metabolism , T-Lymphocytes/drug effects , Animals , Cell Line, Tumor , Combined Modality Therapy/methods , Female , HEK293 Cells , Humans , Immunotherapy, Adoptive/adverse effects , Mice , Neoplasms/immunology , Primary Cell Culture , Receptors, Chimeric Antigen/immunology , Single-Domain Antibodies/immunology , Single-Domain Antibodies/metabolism , T-Cell Antigen Receptor Specificity/drug effects , T-Cell Antigen Receptor Specificity/immunology , T-Lymphocytes/immunology , T-Lymphocytes/metabolism , T-Lymphocytes/transplantation , Xenograft Model Antitumor Assays
2.
Cancer Immunol Res ; 7(2): 282-291, 2019 02.
Article in English | MEDLINE | ID: mdl-30514791

ABSTRACT

Tumor infiltration by immunosuppressive myeloid cells, such as myeloid-derived suppressor cells (MDSCs), causes resistance to immunotherapy. Semaphorin4D, originally characterized for its axonal guidance properties, also contributes to endothelial cell migration and survival and modulates global immune cytokine profiles and myeloid cell polarization within the tumor microenvironment. Here, we show how a therapeutic murine Sema4D mAb improves responses to immune-checkpoint blockade (ICB) in two murine carcinoma models. Treatment of tumor-bearing mice with Sema4D mAb abrogated Ly6Ghi PMN-MDSC recruitment through reducing MAPK-dependent chemokine production by tumor cells in Murine oral cancer-1 (MOC1) tumors. PMN-MDSC suppressive capacity was reduced through inhibition of Sema4D-driven arginase expression. These changes led to enhanced tumor infiltration by CD8+ TIL and activation of tumor-draining lymph node T lymphocytes in response to tumor antigen. Sema4D mAb in combination with either CTLA-4 or PD-1 blockade enhanced rejection of tumors or tumor growth delay, resulting in prolonged survival with either treatment. This function of Sema4D mAb provides a rationale for its evaluation in combination with ICB to treat tumors with immunosuppressive myeloid infiltration.


Subject(s)
Antigens, CD/pharmacology , Antineoplastic Agents, Immunological/pharmacology , Myeloid-Derived Suppressor Cells/drug effects , Myeloid-Derived Suppressor Cells/immunology , Myeloid-Derived Suppressor Cells/metabolism , Semaphorins/pharmacology , Animals , Arginase/metabolism , CTLA-4 Antigen/antagonists & inhibitors , CTLA-4 Antigen/metabolism , Cell Line, Tumor , Chemokines/metabolism , Humans , Mice , Neoplasms/drug therapy , Neoplasms/immunology , Neoplasms/metabolism , Neoplasms/pathology , Neovascularization, Pathologic/drug therapy , Neovascularization, Pathologic/immunology , Neovascularization, Pathologic/metabolism , Programmed Cell Death 1 Receptor/antagonists & inhibitors , Programmed Cell Death 1 Receptor/metabolism , T-Cell Antigen Receptor Specificity/drug effects , T-Lymphocyte Subsets/drug effects , T-Lymphocyte Subsets/immunology , T-Lymphocyte Subsets/metabolism , Tumor Microenvironment/drug effects , Xenograft Model Antitumor Assays
3.
Cytotherapy ; 20(4): 524-531, 2018 04.
Article in English | MEDLINE | ID: mdl-29496461

ABSTRACT

Virus-specific T-cell (VST) infusion becomes a promising alternative treatment for refractory viral infections after hematopoietic stem cell transplantation (HSCT). However, VSTs are often infused during an immunosuppressive treatment course, especially corticosteroids, which are a first-line curative treatment of graft-versus-host disease (GVHD). We were interested in whether corticosteroids could affect adenovirus (ADV)-VST functions. After interferon (IFN)-γ based immunomagnetic selection, ADV-VSTs were in vitro expanded according to three different culture conditions: without methylprednisolone (MP; n = 7), with a final concentration of MP 1 µg/mL (n = 7) or MP 2 µg/mL (n = 7) during 28 ± 11 days. Efficacy and alloreactivity of expanded ADV-VSTs was controlled in vitro. MP transitorily inhibited ADV-VST early expansion. No impairment of specific IFN-γ secretion capacity and cytotoxicity of ADV-VSTs was observed in the presence of MP. However, specific proliferation and alloreactivity of ADV-VSTs were decreased in the presence of MP. Altogether, these results and the preliminary encouraging clinical experiences of co-administration of MP 1 mg/kg and ADV-VSTs will contribute to safe and efficient use of anti-viral immunotherapy.


Subject(s)
Adenoviridae/immunology , Methylprednisolone/pharmacology , T-Cell Antigen Receptor Specificity/drug effects , T-Lymphocytes/drug effects , T-Lymphocytes/immunology , Adenoviridae Infections/immunology , Adenoviridae Infections/therapy , Cell Proliferation/drug effects , Cells, Cultured , Hematopoietic Stem Cell Transplantation , Humans , Immunomagnetic Separation/methods , Immunotherapy , Interferon-gamma/chemistry , Interferon-gamma/metabolism , T-Lymphocytes/cytology , T-Lymphocytes/physiology , Virus Diseases/immunology , Virus Diseases/therapy
4.
Clin Cancer Res ; 24(1): 106-119, 2018 01 01.
Article in English | MEDLINE | ID: mdl-29061640

ABSTRACT

Purpose: Multiple myeloma remains an incurable malignancy of plasma cells despite considerable advances in treatment. The purpose of the study was to develop novel chimeric antigen receptors (CAR) for the treatment of multiple myeloma and explore combinatorial therapy using CAR T cells and immunomodulatory drugs such as lenalidomide for increasing treatment efficacy.Experimental Design: We redirected central memory T cells to express second-generation CAR-specific for CS1 and adoptively transferred them into multiple myeloma tumor-bearing mice to test their anti-multiple myeloma activity. CS1 CAR T cells were transduced and expanded in the presence of lenalidomide in vitro The phenotype and effector function of CS1 CAR T cells treated with and without lenalidomide were compared. Finally, CS1 CAR T cells and lenalidomide were administered to treat multiple myeloma-bearing mice as combinatorial therapy.Results: CS1 CAR T cells exhibited efficient antitumor activity when adoptively transferred into mice. Mechanistic studies indicated that the addition of lenalidomide during CS1 CAR T-cell expansion in vitro enhanced the immune functions of CS1 CAR T cells, including cytotoxicity, memory maintenance, Th1 cytokine production, and immune synapse formation. Furthermore, lenalidomide enhanced the antitumor activity and persistence of adoptively transferred CS1 CAR T cells in vivoConclusions: The study demonstrates that lenalidomide improves the anti-multiple myeloma properties of CS1-directed CAR T cells and provides a basis for a planned clinical trial using the combination of lenalidomide with engineered T cells against CS1 in relapsed myeloma. Clin Cancer Res; 24(1); 106-19. ©2017 AACR.


Subject(s)
Lenalidomide/pharmacology , Multiple Myeloma/immunology , Multiple Myeloma/metabolism , Receptors, Antigen, T-Cell/metabolism , Receptors, Chimeric Antigen/metabolism , Signaling Lymphocytic Activation Molecule Family/genetics , T-Lymphocytes/immunology , T-Lymphocytes/metabolism , Angiogenesis Inhibitors/pharmacology , Animals , Cell Line, Tumor , Cytotoxicity, Immunologic/drug effects , Disease Models, Animal , Dose-Response Relationship, Drug , Gene Expression Profiling , Gene Expression Regulation, Neoplastic , Humans , Immunologic Factors/pharmacology , Immunological Synapses/immunology , Immunotherapy, Adoptive , Mice , Multiple Myeloma/pathology , Multiple Myeloma/therapy , Receptors, Chimeric Antigen/genetics , Signaling Lymphocytic Activation Molecule Family/immunology , T-Cell Antigen Receptor Specificity/drug effects , T-Lymphocytes/drug effects , Xenograft Model Antitumor Assays
5.
J Immunother Cancer ; 4: 68, 2016.
Article in English | MEDLINE | ID: mdl-27777777

ABSTRACT

BACKGROUND: Future cancer immunotherapies will combine multiple treatments to generate functional immune responses to cancer antigens through synergistic, multi-modal mechanisms. In this study we explored the combination of three distinct immunotherapies: a class I restricted peptide-based cancer vaccine, metronomic cyclophosphamide (mCPA) and anti-PD-1 treatment in a murine tumor model expressing HPV16 E7 (C3). METHODS: Mice were implanted with C3 tumors subcutaneously. Tumor bearing mice were treated with mCPA (20 mg/kg/day PO) for seven continuous days on alternating weeks, vaccinated with HPV16 E749-57 peptide antigen formulated in the DepoVax (DPX) adjuvanting platform every second week, and administered anti-PD-1 (200 µg/dose IP) after each vaccination. Efficacy was measured by following tumor growth and survival. Immunogenicity was measured by IFN-γ ELISpot of spleen, vaccine draining lymph nodes and tumor draining lymph nodes. Tumor infiltration was measured by flow cytometry for CD8α+ peptide-specific T cells and RT-qPCR for cytotoxic proteins. The clonality of tumor infiltrating T cells was measured by TCRß sequencing using genomic DNA. RESULTS: Untreated C3 tumors had low expression of PD-L1 in vivo and anti-PD-1 therapy alone provided no protection from tumor growth. Treatment with DPX/mCPA could delay tumor growth, and tri-therapy with DPX/mCPA/anti-PD-1 provided long-term control of tumors. We found that treatment with DPX/mCPA/anti-PD-1 enhanced systemic antigen-specific immune responses detected in the spleen as determined by IFN-γ ELISpot compared to those in the DPX/mCPA group, but immune responses in tumor-draining lymph nodes were not increased. Although no increases in antigen-specific CD8α+ TILs could be detected, there was a trend for increased expression of cytotoxic genes within the tumor microenvironment as well as an increase in clonality in mice treated with DPX/mCPA/anti-PD-1 compared to those with anti-PD-1 alone or DPX/mCPA. Using a library of antigen-specific CD8α+ T cell clones, we found that antigen-specific clones were more frequently expanded in the DPX/mCPA/anti-PD-1 treated group. CONCLUSIONS: These results demonstrate how the efficacy of anti-PD-1 may be improved by combination with a potent and targeted T cell activating immune therapy.


Subject(s)
Antineoplastic Agents, Immunological/pharmacology , Cancer Vaccines/immunology , Cyclophosphamide/administration & dosage , Lymphocytes, Tumor-Infiltrating/drug effects , Lymphocytes, Tumor-Infiltrating/immunology , Neoplasms/immunology , Programmed Cell Death 1 Receptor/antagonists & inhibitors , T-Lymphocyte Subsets/drug effects , T-Lymphocyte Subsets/immunology , Administration, Metronomic , Animals , Antineoplastic Agents, Immunological/therapeutic use , B7-H1 Antigen/genetics , B7-H1 Antigen/metabolism , CD8-Positive T-Lymphocytes/drug effects , CD8-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/metabolism , Cell Line, Tumor , Clonal Evolution/drug effects , Clonal Evolution/immunology , Cytotoxicity, Immunologic , Disease Models, Animal , Epitopes, T-Lymphocyte/chemistry , Epitopes, T-Lymphocyte/immunology , Female , Gene Expression , Humans , Immunomodulation/drug effects , Lymphocytes, Tumor-Infiltrating/metabolism , Mice , Neoplasms/metabolism , Neoplasms/pathology , Neoplasms/therapy , Programmed Cell Death 1 Receptor/genetics , Programmed Cell Death 1 Receptor/metabolism , T-Cell Antigen Receptor Specificity/drug effects , T-Cell Antigen Receptor Specificity/immunology , T-Lymphocyte Subsets/metabolism , Tumor Microenvironment/drug effects , Tumor Microenvironment/immunology
6.
Leuk Lymphoma ; 55(5): 1144-50, 2014 May.
Article in English | MEDLINE | ID: mdl-23841510

ABSTRACT

Abstract Everolimus (RAD-001) has recently been used as an immunosuppressive drug to treat patients after hematopoietic stem cell transplant (HSCT), thereby reducing cyclosporine-related nephrotoxicity. We studied the immunomodulatory effect of everolimus on mitogen-stimulated and particularly cytomegalovirus (CMV)-specific cytotoxic T cells. Proliferation of CD4(+) and CD8(+) T cells stimulated with staphylococcal endotoxin B and phytohemagglutinin was strongly inhibited at very low doses. Proliferation of CMV-specific CD8(+) T cells could be completely suppressed. Similarly, the frequency of CMV-specific, cytokine-secreting and CD137-expressing CD8(+) T cells decreased in a dose-dependent manner. However, interferon-γ (IFN-γ) secretion by CMV-specific CD8(+) T cells remained unchanged, as could be demonstrated by intracellular cytokine staining. As reactivation of CMV plays a pivotal role in the outcome of patients after HSCT, attention must be paid to early detection and preemptive treatment of CMV reactivity in patients treated with everolimus.


Subject(s)
CD8-Positive T-Lymphocytes/drug effects , CD8-Positive T-Lymphocytes/immunology , Cytomegalovirus Infections/immunology , Cytomegalovirus/immunology , Immunosuppressive Agents/pharmacology , Sirolimus/analogs & derivatives , T-Cell Antigen Receptor Specificity/drug effects , T-Cell Antigen Receptor Specificity/immunology , CD8-Positive T-Lymphocytes/metabolism , Everolimus , Humans , Inhibitory Concentration 50 , Interferon-gamma/biosynthesis , Lymphocyte Activation/drug effects , Lymphocyte Activation/immunology , Phosphoproteins/immunology , Sirolimus/pharmacology , Tumor Necrosis Factor Receptor Superfamily, Member 9/metabolism , Viral Matrix Proteins/immunology
7.
Cancer Res ; 73(22): 6597-608, 2013 Nov 15.
Article in English | MEDLINE | ID: mdl-24048821

ABSTRACT

Antitumor immunity is strongly influenced by the balance of tumor antigen-specific effector T cells (Teff) and regulatory T cells (Treg). However, the impact that vaccine adjuvants have in regulating the balance of antigen-specific T-cell populations is not well understood. We found that antigen-specific Tregs were induced following subcutaneous vaccination with either OVA or melanoma-derived peptides, with a restricted expansion of Teffs. Addition of the adjuvants CpG-ODN or Poly(I:C) preferentially amplified Teffs over Tregs, dramatically increasing the antigen-specific Teff:Treg ratios and inducing polyfunctional effector cells. In contrast, two other adjuvants, imiquimod and Quil A saponin, favored an expansion of antigen-specific Tregs and failed to increase Teff:Treg ratios. Following therapeutic vaccination of tumor-bearing mice, high ratios of tumor-specific Teffs:Tregs in draining lymph nodes were associated with enhanced CD8(+) T-cell infiltration at the tumor site and a durable rejection of tumors. Vaccine formulations of peptide+CpG-ODN or Poly(I:C) induced selective production of proinflammatory type I cytokines early after vaccination. This environment promoted CD8(+) and CD4(+) Teff expansion over that of antigen-specific Tregs, tipping the Teff to Treg balance to favor effector cells. Our findings advance understanding of the influence of different adjuvants on T-cell populations, facilitating the rational design of more effective cancer vaccines.


Subject(s)
Adjuvants, Immunologic/pharmacology , Immunity, Cellular/drug effects , Neoplasms/immunology , T-Cell Antigen Receptor Specificity/drug effects , T-Lymphocytes, Helper-Inducer/drug effects , T-Lymphocytes, Regulatory/drug effects , Adjuvants, Immunologic/administration & dosage , Animals , Antigens/immunology , Cancer Vaccines/administration & dosage , Female , Lymphocyte Count , Male , Mice , Mice, Inbred C57BL , Mice, Transgenic , Neoplasms/therapy , T-Lymphocytes, Helper-Inducer/immunology , T-Lymphocytes, Helper-Inducer/pathology , T-Lymphocytes, Regulatory/immunology , T-Lymphocytes, Regulatory/pathology , Treatment Outcome , Tumor Cells, Cultured
8.
Blood ; 120(22): 4374-82, 2012 Nov 22.
Article in English | MEDLINE | ID: mdl-23033269

ABSTRACT

SOCS3 is a feedback regulator of cytokine signaling that affects T-cell polarization. Human tuberculosis is accompanied by increased SOCS3 expression in T cells, and this may influence susceptibility against Mycobacterium tuberculosis. Because the role of SOCS3 in human T-cell function is not well defined, we characterized cytokine expression and proliferation of human T cells with differential SOCS3 expression in the present study. We established a flow cytometry-based method for SOCS3 protein quantification and detected higher SOCS3 levels induced by M tuberculosis specific T-cell activation and a transient decrease of SOCS3 expression in the presence of mycobacteria-infected macrophages. Notably increased SOCS3 expression was detected in IL-17-expressing T-cell clones and in CD161(+) T helper type 17 cells ex vivo. Ectopic SOCS3 expression in primary CD4(+) T cells by lentiviral transduction induced increased IL-17 production but diminished proliferation and viability. Recombinant IL-7 inhibited SOCS3 expression and reduced IL-17-expressing T-cell proportions. We concluded that higher SOCS3 expression in human T cells favors T helper type 17 cells. Therefore, increased SOCS3 expression in human tuberculosis may reflect polarization toward IL-17-expressing T cells as well as T-cell exhaustion marked by reduced proliferation.


Subject(s)
Interleukin-17/genetics , Suppressor of Cytokine Signaling Proteins/physiology , T-Lymphocytes/metabolism , CD4-Positive T-Lymphocytes/drug effects , CD4-Positive T-Lymphocytes/metabolism , CD4-Positive T-Lymphocytes/physiology , Cell Proliferation/drug effects , Cells, Cultured , Flow Cytometry , Gene Expression Regulation , Humans , Interleukin-17/metabolism , Interleukin-17/pharmacology , Lymphocyte Activation/genetics , Mycobacterium tuberculosis/immunology , Suppressor of Cytokine Signaling 3 Protein , Suppressor of Cytokine Signaling Proteins/genetics , Suppressor of Cytokine Signaling Proteins/metabolism , T-Cell Antigen Receptor Specificity/drug effects , T-Cell Antigen Receptor Specificity/genetics , T-Lymphocytes/drug effects , T-Lymphocytes/immunology , T-Lymphocytes/physiology , Transfection , Tuberculosis/immunology , Up-Regulation/genetics
9.
Br J Haematol ; 158(6): 700-11, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22816680

ABSTRACT

Patients with multiple myeloma (MM) undergoing high dose therapy and autologous stem cell transplantation (SCT) remain at risk for disease progression. Induction of the expression of highly immunogenic cancer testis antigens (CTA) in malignant plasma cells in MM patients may trigger a protective immune response following SCT. We initiated a phase II clinical trial of the DNA hypomethylating agent, azacitidine (Aza) administered sequentially with lenalidomide (Rev) in patients with MM. Three cycles of Aza and Rev were administered and autologous lymphocytes were collected following the 2nd and 3rd cycles of Aza-Rev and cryopreserved. Subsequent stem cell mobilization was followed by high-dose melphalan and SCT. Autologous lymphocyte infusion (ALI) was performed in the second month following transplantation. Fourteen patients have completed the investigational therapy; autologous lymphocytes were collected from all of the patients. Thirteen patients have successfully completed SCT and 11 have undergone ALI. Six patients tested have demonstrated CTA up-regulation in either unfractionated bone marrow (n = 4) or CD138+ cells (n = 2). CTA (CTAG1B)-specific T cell response has been observed in all three patients tested and persists following SCT. Epigenetic induction of an adaptive immune response to cancer testis antigens is safe and feasible in MM patients undergoing SCT.


Subject(s)
Antigens, Neoplasm/immunology , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Azacitidine/pharmacology , DNA Methylation/drug effects , Epigenesis, Genetic/drug effects , Immunity, Cellular/drug effects , Lymphocyte Transfusion , Multiple Myeloma/immunology , Peripheral Blood Stem Cell Transplantation , T-Cell Antigen Receptor Specificity/drug effects , Adult , Aged , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Azacitidine/administration & dosage , Boronic Acids/administration & dosage , Bortezomib , Dexamethasone/administration & dosage , Doxorubicin/administration & dosage , Drug Administration Schedule , Female , Humans , Lenalidomide , Male , Middle Aged , Multiple Myeloma/drug therapy , Multiple Myeloma/surgery , Plasma Cells/immunology , Prospective Studies , Pyrazines/administration & dosage , Thalidomide/administration & dosage , Thalidomide/analogs & derivatives , Transplantation, Autologous
10.
Blood ; 119(19): 4441-50, 2012 May 10.
Article in English | MEDLINE | ID: mdl-22310911

ABSTRACT

Immune responses to foreign and self-Ags can be controlled by regulatory T cells (Tregs) expressing CD4 and IL-2Rα chain (CD25). Defects in Tregs lead to autoimmunity, whereas induction of Ag-specific CD4+CD25+ Tregs restores tolerance. Ag-specific CD4+CD25+ FOXP3+Tregs activated by the T helper type 2 (Th2) cytokine, IL-4, and specific alloantigen promote allograft tolerance. These Tregs expressed the specific IL-5Rα and in the presence of IL-5 proliferate to specific but not third-party Ag. These findings suggest that recombinant IL-5 (rIL-5) therapy may promote Ag-specific Tregs to mediate tolerance. This study showed normal CD4+CD25+ Tregs cultured with IL-4 and an autoantigen expressed Il-5rα. Treatment of experimental autoimmune neuritis with rIL-5 markedly reduced clinical paralysis, weight loss, demyelination, and infiltration of CD4+ (Th1 and Th17) CD8+ T cells and macrophages in nerves. Clinical improvement was associated with expansion of CD4+CD25+FOXP3+ Tregs that expressed Il-5rα and proliferated only to specific autoantigen that was enhanced by rIL-5. Depletion of CD25+ Tregs or blocking of IL-4 abolished the benefits of rIL-5. Thus, rIL-5 promoted Ag-specific Tregs, activated by autoantigen and IL-4, to control autoimmunity. These findings may explain how Th2 responses, especially to parasitic infestation, induce immune tolerance. rIL-5 therapy may be able to induce Ag-specific tolerance in autoimmunity.


Subject(s)
Autoimmunity/drug effects , CD4 Antigens/metabolism , Interleukin-2 Receptor alpha Subunit/metabolism , Interleukin-5/pharmacology , T-Lymphocytes, Regulatory/drug effects , Animals , Antigens, Differentiation, T-Lymphocyte/metabolism , Autoimmunity/immunology , CHO Cells , Cricetinae , Cricetulus , Down-Regulation/drug effects , Down-Regulation/immunology , Drug Evaluation, Preclinical , Female , Immune Tolerance/drug effects , Rats , Rats, Inbred Lew , Recombinant Proteins/pharmacology , T-Cell Antigen Receptor Specificity/drug effects , T-Lymphocytes, Regulatory/metabolism , T-Lymphocytes, Regulatory/physiology
11.
Blood ; 118(18): 4853-62, 2011 Nov 03.
Article in English | MEDLINE | ID: mdl-21908423

ABSTRACT

Regulatory T cells (Tregs) may impede cancer vaccine efficacy in hematologic malignancies and cancer. CCR4 antagonists, an emergent class of Treg inhibitor, have been shown to block recruitment of Tregs mediated by CCL22 and CCL17. Our aim was to demonstrate the ability of a CCR4 antagonist (a small chemical molecule identified in silico) when combined with vaccines to break peripheral tolerance controlled by Tregs, a prerequisite for the induction of CD8(+) T cells against self Ags. Immunization of transgenic or normal mice expressing tumor-associated self Ags (Her2/neu, OVA, gp100) with a CCR4 antagonist combined with various vaccines led to the induction of effector CD8(+) T cells and partial inhibition of tumor growth expressing self Ags in both prophylactic and therapeutic settings. The CCR4 antagonist was more efficient than cyclophosphamide to elicit anti-self CD8(+) T cells. We also showed that the population of Tregs expressing CCR4 corresponded to memory (CD44(high)) and activated (ICOS(+)) Tregs, an important population to be targeted to modulate Treg activity. CCR4 antagonist represents a competitive class of Treg inhibitor able to induce functional anti-self CD8(+) T cells and tumor growth inhibition when combined with vaccines. High expression of CCR4 on human Tregs also supports the clinical development of this strategy.


Subject(s)
Autoantigens/immunology , CD8-Positive T-Lymphocytes/drug effects , Cancer Vaccines/administration & dosage , Neoplasms/therapy , Receptors, CCR4/antagonists & inhibitors , Tumor Escape/drug effects , Animals , Antigens, Neoplasm/immunology , Antineoplastic Agents/administration & dosage , Autoantigens/drug effects , CD8-Positive T-Lymphocytes/immunology , Combined Modality Therapy , Disease Models, Animal , Female , Humans , Immunologic Factors/administration & dosage , Mice , Mice, Inbred C57BL , Mice, Transgenic , Neoplasms/genetics , Neoplasms/immunology , Neoplasms/pathology , T-Cell Antigen Receptor Specificity/drug effects , T-Cell Antigen Receptor Specificity/immunology , Tumor Escape/immunology
12.
Leuk Res ; 35(9): 1241-7, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21612823

ABSTRACT

The interaction between dendritic cells (DCs) and natural killer (NK) cells plays a key role in inducing DC maturation for subsequent T-cell priming. We investigated to generate potent DCs by stimulated with NK cells to induce myeloma-specific cytotoxic T lymphocytes (CTLs). NK cells-stimulated-DCs exhibited high expression of costimulatory molecules and high production of IL-12p70. These DCs induce high potency of Th1 polarization and exhibit a high ability to generate myeloma-specific CTLs responses. These results suggest that functionally potent DCs can be generated by stimulation with NK cells and may provide an effective source of DC-based immunotherapy in multiple myeloma.


Subject(s)
Dendritic Cells/immunology , Killer Cells, Natural/physiology , Lymphocyte Activation/physiology , Multiple Myeloma/immunology , T-Lymphocytes, Cytotoxic/immunology , Cell Polarity/drug effects , Cell Polarity/immunology , Cell Proliferation/drug effects , Cells, Cultured , Cytotoxicity, Immunologic/drug effects , Cytotoxicity, Immunologic/physiology , Dendritic Cells/drug effects , Dendritic Cells/pathology , HL-60 Cells , Humans , Interferon Type I/pharmacology , K562 Cells , Killer Cells, Natural/drug effects , Killer Cells, Natural/immunology , Killer Cells, Natural/pathology , Lymphocyte Activation/drug effects , Lymphocyte Activation/immunology , Multiple Myeloma/pathology , Polydeoxyribonucleotides/pharmacology , Recombinant Proteins , T-Cell Antigen Receptor Specificity/drug effects , T-Cell Antigen Receptor Specificity/immunology , T-Lymphocytes, Cytotoxic/drug effects , T-Lymphocytes, Cytotoxic/pathology
13.
J Clin Oncol ; 29(18): 2493-8, 2011 Jun 20.
Article in English | MEDLINE | ID: mdl-21576633

ABSTRACT

PURPOSE: Blinatumomab, a bispecific single-chain antibody targeting the CD19 antigen, is a member of a novel class of antibodies that redirect T cells for selective lysis of tumor cells. In acute lymphoblastic leukemia (ALL), persistence or relapse of minimal residual disease (MRD) after chemotherapy indicates resistance to chemotherapy and results in hematologic relapse. A phase II clinical study was conducted to determine the efficacy of blinatumomab in MRD-positive B-lineage ALL. PATIENTS AND METHODS: Patients with MRD persistence or relapse after induction and consolidation therapy were included. MRD was assessed by quantitative reverse transcriptase polymerase chain reaction for either rearrangements of immunoglobulin or T-cell receptor genes, or specific genetic aberrations. Blinatumomab was administered as a 4-week continuous intravenous infusion at a dose of 15 µg/m2/24 hours. RESULTS: Twenty-one patients were treated, of whom 16 patients became MRD negative. One patient was not evaluable due to a grade 3 adverse event leading to treatment discontinuation. Among the 16 responders, 12 patients had been molecularly refractory to previous chemotherapy. Probability for relapse-free survival is 78% at a median follow-up of 405 days. The most frequent grade 3 and 4 adverse event was lymphopenia, which was completely reversible like most other adverse events. CONCLUSION: Blinatumomab is an efficacious and well-tolerated treatment in patients with MRD-positive B-lineage ALL after intensive chemotherapy. T cells engaged by blinatumomab seem capable of eradicating chemotherapy-resistant tumor cells that otherwise cause clinical relapse.


Subject(s)
Antibodies, Bispecific/therapeutic use , Drug Delivery Systems , Immunotherapy/methods , Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/therapy , T-Lymphocytes, Cytotoxic/drug effects , Adult , Agammaglobulinemia/chemically induced , Aged , Aged, 80 and over , Antibodies, Bispecific/adverse effects , Antibodies, Bispecific/pharmacokinetics , Antibody Specificity , Antigens, CD19/immunology , Antigens, Neoplasm/immunology , B-Lymphocytes/immunology , B-Lymphocytes/pathology , Bone Marrow/pathology , CD3 Complex/immunology , Cell Lineage , Combined Modality Therapy , Disease-Free Survival , Drug Resistance, Neoplasm , Female , Humans , Kaplan-Meier Estimate , Lymphocyte Activation , Lymphopenia/chemically induced , Male , Middle Aged , Molecular Targeted Therapy , Neoplasm, Residual , Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/drug therapy , Remission Induction , T-Cell Antigen Receptor Specificity/drug effects , T-Cell Antigen Receptor Specificity/immunology , T-Lymphocytes, Cytotoxic/immunology , Young Adult
14.
Int J Hematol ; 93(5): 594-601, 2011 May.
Article in English | MEDLINE | ID: mdl-21475951

ABSTRACT

Alloreactive donor T cells are central to the pathogenesis of Graft-versus-Host Disease (GvHD). Non-specific T cell depletion of donor grafts reduces GvHD, but increases infection and disease relapse. Several strategies are, therefore, in development to selectively remove alloreactive donor T cells prior to transplant while retaining beneficial donor T cells. An alternative approach is ex vivo alloanergization of donor T cells via allostimulation and blockade of costimulatory signals with fusion proteins or monoclonal antibodies. This strategy, which selectively inactivates alloreactive donor T cells, has been tested with some success in previous clinical trials of HLA-mismatched bone marrow transplantation. To build on the findings of these early trials, the strategy is now being tested in a multi-center clinical study of alloanergized donor lymphocyte infusion after HLA-mismatched stem cell transplantation. Recent advances in the understanding of alloanergization include the recognition of the central role played by CD4(+) regulatory T cells and new applications include the combination of alloanergization with T cell redirection to maximize anti-tumor activity. This mini-review will give an overview of the immunological basis for alloanergization, the previous and current clinical applications, and how new pre-clinical data have helped to create exciting new avenues of translational research in this area.


Subject(s)
Antibodies, Monoclonal/pharmacology , Clonal Anergy , Graft vs Host Disease/immunology , Graft vs Host Disease/therapy , Hematologic Diseases/therapy , Recombinant Fusion Proteins/pharmacology , T-Cell Antigen Receptor Specificity/drug effects , T-Lymphocytes, Regulatory/immunology , Antibodies, Monoclonal/immunology , Antibodies, Monoclonal/metabolism , Antibody Specificity , Bone Marrow Transplantation/adverse effects , Clinical Trials as Topic , Clonal Anergy/drug effects , Clonal Anergy/immunology , Graft vs Host Disease/physiopathology , Graft vs Host Disease/prevention & control , HLA Antigens/analysis , Hematologic Diseases/immunology , Humans , In Vitro Techniques , Lymphocyte Depletion/adverse effects , Opportunistic Infections/prevention & control , Recombinant Fusion Proteins/immunology , Recombinant Fusion Proteins/metabolism , Transplantation, Homologous
15.
Eur J Immunol ; 40(7): 1973-84, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20468055

ABSTRACT

A novel T-cell vaccine strategy designed to deal with the enormity of HIV-1 variation is described and tested for the first time in macaques to inform and complement approaching clinical trials. T-cell immunogen HIVconsv, which directs vaccine-induced responses to the most conserved regions of the HIV-1, proteome and thus both targets diverse clades in the population and reduces the chance of escape in infected individuals, was delivered using six different vaccine modalities: plasmid DNA (D), attenuated human (A) and chimpanzee (C) adenoviruses, modified vaccinia virus Ankara (M), synthetic long peptides, and Semliki Forest virus replicons. We confirmed that the initial DDDAM regimen, which mimics one of the clinical schedules (DDDCM), is highly immunogenic in macaques. Furthermore, adjuvanted synthetic long peptides divided into sub-pools and delivered into anatomically separate sites induced T-cell responses that were markedly broader than those elicited by traditional single-open-reading-frame genetic vaccines and increased by 30% the overall response magnitude compared with DDDAM. Thus, by improving both the HIV-1-derived immunogen and vector regimen/delivery, this approach could induce stronger, broader, and theoretically more protective T-cell responses than vaccines previously used in humans.


Subject(s)
AIDS Vaccines , HIV Antigens/administration & dosage , HIV-1/immunology , Peptide Fragments/administration & dosage , T-Lymphocytes/metabolism , Animals , Cell Proliferation/drug effects , Conserved Sequence/genetics , Drug Delivery Systems , Epitope Mapping/methods , Epitopes, T-Lymphocyte/genetics , Genetic Vectors , HIV Antigens/genetics , Humans , Immunization , Lymphocyte Activation/drug effects , Macaca mulatta , Peptide Fragments/genetics , Peptide Library , T-Cell Antigen Receptor Specificity/drug effects , T-Lymphocytes/drug effects , T-Lymphocytes/immunology , T-Lymphocytes/pathology
16.
Zhonghua Yu Fang Yi Xue Za Zhi ; 44(1): 14-7, 2010 Jan.
Article in Chinese | MEDLINE | ID: mdl-20388357

ABSTRACT

OBJECTIVE: To investigate the early changes of some immunological function of T-cell in chromate workers. METHODS: A total of 115 workers exposed to different levels of soluble chromate were enrolled in exposed group; while 90 non-exposure workers who lived far away from the chromate plant were enrolled as control. The air concentration of soluble chromate was determined by atomic absorption spectrometry. CD3(+), CD3(+)CD4(+), CD3(+)CD8(+) and CD4(+)/CD8(+) of T-cell were determined by flow cytometry analysis. RESULTS: The individual air chromate concentration in the exposed group was (27.51 +/- 33.25) microg/m(3), and the control group was (0.16 +/- 0.15) microg/m(3). The significant difference between the two groups was observed (z = 8.045, P < 0.01). The levels of the lymphocyte subsets (CD3(+), CD3(+)CD4(+), CD3(+)CD8(+) and CD4(+)/CD8(+)) in exposed group were (30.08 +/- 17.75)%, (1.04 +/- 1.73)%, (11.94 +/- 9.78)%, 0.10 +/- 0.14. While, those of control group were (63.00 +/- 13.57)%, (30.51 +/- 5.16)%, (14.82 +/- 4.59)%, 2.17 +/- 0.53, higher than that of the exposed group (z values were 4.484, 5.227, 1.976, -5.218, respectively, P < 0.05). CONCLUSION: On the basis of individual air monitoring, the cellular immune function affected by soluble chromate is mainly based on T lymphocyte inhibition. The indicators CD3(+)CD4(+) mentioned above may be considered as efficient biomarkers in further research.


Subject(s)
Chromates/adverse effects , Occupational Exposure , T-Lymphocytes/drug effects , T-Lymphocytes/immunology , Adult , CD4-CD8 Ratio , Case-Control Studies , Female , Humans , Male , Middle Aged , T-Cell Antigen Receptor Specificity/drug effects , T-Cell Antigen Receptor Specificity/immunology
17.
Allergy ; 65(10): 1322-30, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20415720

ABSTRACT

BACKGROUND: Innate immune response by a viral pathogen-associated molecular pattern dsRNA modulates the subsequent development of adaptive immune responses. Although virus-associated asthma is characterized by noneosinophilic inflammation, the role of Th17 cell response in the development of virus-associated asthma is still unknown. OBJECTIVE: To evaluate the role of the Th17 cell response and its underlying polarizing mechanisms in the development of an experimental virus-associated asthma. METHODS: An experimental virus-associated asthma was created via airway sensitization with ovalbumin (OVA, 75 µg) and a low (0.1 µg) or a high (10 µg) doses of synthetic dsRNA [polyinosine-polycytidylic acid; poly(I:C)]. Transgenic (IL-17-, IL-6-deficient mice) and pharmacologic [a vascular endothelial growth factor receptor (VEGFR) inhibitor] approaches were used to evaluate the roles of Th17 cell responses. RESULTS: After cosensitization with OVA and low-dose poly(I:C), but not with high-dose poly(I:C), inflammation scores after allergen challenge were lower in IL-17-deficient mice than in wild-type (WT) mice. Moreover, inflammation enhanced by low-dose poly(I:C), but not by high-dose poly(I:C), was impaired in IL-6-deficient mice; this phenotype was accompanied by the down-regulation of IL-17 production from T cells from both lymph nodes and lung tissues. Airway exposure of low-dose poly(I:C) enhanced the production of VEGF and IL-6, and the production of IL-6 was blocked by treatment with a VEGFR inhibitor (SU5416). Moreover, the allergen-specific Th17 cell response and subsequent inflammation in the low-dose poly(I:C) model were impaired by the VEGFR inhibitor treatment during sensitization. CONCLUSIONS: Airway exposure of low-level dsRNA induces an allergen-specific Th17 cell response, which is mainly dependent on VEGF and IL-6.


Subject(s)
Asthma/virology , Interleukin-6/biosynthesis , RNA, Double-Stranded/adverse effects , RNA, Viral/adverse effects , Th17 Cells/immunology , Vascular Endothelial Growth Factor A/biosynthesis , Adaptive Immunity , Allergens/immunology , Animals , Asthma/immunology , Dose-Response Relationship, Drug , Immunity, Innate , Mice , Mice, Transgenic , Ovalbumin/pharmacology , Poly I-C/pharmacology , Respiratory System/immunology , Respiratory System/virology , T-Cell Antigen Receptor Specificity/drug effects , T-Cell Antigen Receptor Specificity/immunology
18.
Curr Opin Allergy Clin Immunol ; 8(4): 299-307, 2008 Aug.
Article in English | MEDLINE | ID: mdl-18596585

ABSTRACT

PURPOSE OF REVIEW: The purpose of this review is to highlight recent studies on drug metabolism in T-cell-mediated reactions. Although the hapten theory and the danger hypothesis imply an important role of reactive metabolites in the pathogenesis of drug hypersensitivity, the more recent pi concept gives the central role to the parent drug. It is therefore important to have a broad vision on data supporting each theory to understand the potential role(s) of drug metabolism in T-cell-mediated hypersensitivity. RECENT FINDINGS: Reactive metabolites have been identified for most drugs associated with hypersensitivity. Recent studies have further characterized drug metabolism outside the liver, in key tissues such as the skin and immune cells. Localized drug metabolism is associated with oxidative stress, adduct formation and toxicity creating danger signals for antigen presenting cells, influencing whether a drug antigen will induce tolerance or immunity. SUMMARY: The involvement of metabolic drug activation in the initiation and propagation of hypersensitivity is intriguing since metabolites are generated in different quantities throughout the body, can be directly or indirectly toxic to cells, might stimulate innate immunity, and can bind to protein to generate neoantigens for cellular and humoral responses.


Subject(s)
Drug Hypersensitivity/etiology , Drug Hypersensitivity/metabolism , Immunity, Cellular/drug effects , Pharmaceutical Preparations/metabolism , T-Lymphocytes/cytology , Animals , Biotransformation/immunology , Drug Hypersensitivity/immunology , Drug Hypersensitivity/physiopathology , Drug-Related Side Effects and Adverse Reactions , Humans , Immune Tolerance , Oxidative Stress/immunology , Pharmaceutical Preparations/chemistry , Pharmacogenetics , Reactive Oxygen Species/adverse effects , Reactive Oxygen Species/immunology , T-Cell Antigen Receptor Specificity/drug effects , T-Lymphocytes/metabolism
19.
J Immunother ; 31(7): 656-64, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18600179

ABSTRACT

Dendritic cells (DCs) are currently considered as promising tools for vaccination against tumors and also autoimmune responses. A major point of concern has been the use of fetal calf serum (FCS) as a source of heterologous antigen in DC cultures. FCS peptides can be presented by the DCs and cause T-cell responses in the recipient. We investigated the role of FCS in an autoimmune model where DC injections can prevent peptide-specifically from experimental autoimmune encephalomyelitis (EAE). We show that murine bone marrow-derived DCs generated in FCS-containing or serum-free media resulting in a similar phenotype, maturation potential, and functions. Peptide-specific protection could be achieved similarly with FCS-DC or serum-free DCs. Although FCS-DC induced strong CD4 T cell proliferation and cytokine production against FCS, these T cells lack antigenic recall during EAE. Even if FCS was reinjected, the effect on EAE resulted only in a 3-day delay of disease onset. Together, our data show that presentation of bystander antigens by peptide-specific DC vaccinations may have little influence on T-cell responses in vivo if the bystander antigen cannot be recalled by specific T cells.


Subject(s)
Antigen Presentation/immunology , Cell Differentiation/immunology , Dendritic Cells/immunology , Encephalomyelitis, Autoimmune, Experimental/prevention & control , Lymphocyte Activation/immunology , Vaccination , Animals , Blood Proteins/immunology , CD4-Positive T-Lymphocytes/cytology , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/metabolism , Cattle , Cell Proliferation/drug effects , Culture Media, Serum-Free , Encephalomyelitis, Autoimmune, Experimental/immunology , Mice , Peptides/immunology , T-Cell Antigen Receptor Specificity/drug effects , T-Cell Antigen Receptor Specificity/immunology
20.
Int Immunol ; 20(7): 893-900, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18492659

ABSTRACT

Whether also antigen-experienced CD4(+) T cell populations undergo modulations upon oral antigen uptake supporting systemic unresponsiveness is still not fully understood. Using an adoptive transfer model with chicken ovalbumin (OVA)-specific T cells, we demonstrated that absolute numbers of transferred ex vivo-isolated CD4(+) memory T cells and in vitro-polarized T(h)1 cells considerably decrease within spleen and liver upon repetitive OVA feeding. As a consequence, these mice did not mount a delayed-type hypersensitivity reaction after OVA challenge. OVA-specific T(h)1 cells re-isolated from the liver showed augmented signs of apoptosis. However, there was no evidence that transferred effector or memory T cells acquired a regulatory phenotype, became anergic or underwent immune deviation. Our data suggest that oral antigen application does not induce alterations in the phenotype of CD4(+) effector and memory T cells. Instead, deletion of antigen-experienced CD4(+) T cells preferentially within the liver might be a major mechanism contributing to antigen-specific systemic unresponsiveness upon oral antigen uptake.


Subject(s)
CD4-Positive T-Lymphocytes/immunology , Clonal Deletion , Th1 Cells/immunology , Administration, Oral , Adoptive Transfer , Animals , CD4-Positive T-Lymphocytes/metabolism , Cell Count , Cytokines/metabolism , Immunologic Memory , Mice , Mice, Inbred BALB C , Mice, Transgenic , Ovalbumin/administration & dosage , Ovalbumin/immunology , T-Cell Antigen Receptor Specificity/drug effects , T-Cell Antigen Receptor Specificity/immunology , Th1 Cells/drug effects , Th1 Cells/metabolism , Vaccination
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