ABSTRACT
Amyotrophic lateral sclerosis (ALS) is an orphan neurodegenerative disease. Immune system dysregulation plays an essential role in ALS onset and progression. Our preclinical studies have shown that the administration of exogenous allogeneic B cells improves outcomes in murine models of skin and brain injury through a process termed pligodraxis, in which B cells adopt an immunoregulatory and neuroprotective phenotype in an injured environment. Here, we investigated the effects of B-cell therapy in the SOD1G93A mouse preclinical model of ALS and in a person living with ALS. Purified splenic mature naïve B cells from haploidentical donor mice were administered intravenously in SOD1G93A mice for a total of 10 weekly doses. For the clinical study in a person with advanced ALS, IgA gammopathy of unclear significance, and B lymphopenia, CD19+ B cells were positively selected from a healthy haploidentical donor and infused intravenously twice, at a 60-day interval. Repeated intravenous B-cell administration was safe and significantly delayed disease onset, extended survival, reduced cellular apoptosis, and decreased astrogliosis in SOD1G93A mice. Repeated B-cell infusion in a person with ALS was safe and did not appear to generate a clinically evident inflammatory response. An improvement of 5 points on the ALSFRS-R scale was observed after the first infusion. Levels of inflammatory markers showed persistent reduction post-infusion. This represents a first demonstration of the efficacy of haploidentical B-cell infusion in the SOD1G93A mouse and the safety and feasibility of using purified haploidentical B lymphocytes as a cell-based therapeutic strategy for a person with ALS.
Subject(s)
Amyotrophic Lateral Sclerosis , B-Lymphocytes , Amyotrophic Lateral Sclerosis/therapy , Amyotrophic Lateral Sclerosis/immunology , Animals , Mice , Humans , B-Lymphocytes/immunology , Disease Models, Animal , Mice, Transgenic , Male , Female , Mice, Inbred C57BL , Immunomodulation , Middle AgedABSTRACT
BACKGROUND: Sickle cell disease is characterized by hemolytic anemia, pain, and progressive organ damage. A high level of erythrocyte fetal hemoglobin (HbF) comprising α- and γ-globins may ameliorate these manifestations by mitigating sickle hemoglobin polymerization and erythrocyte sickling. BCL11A is a repressor of γ-globin expression and HbF production in adult erythrocytes. Its down-regulation is a promising therapeutic strategy for induction of HbF. METHODS: We enrolled patients with sickle cell disease in a single-center, open-label pilot study. The investigational therapy involved infusion of autologous CD34+ cells transduced with the BCH-BB694 lentiviral vector, which encodes a short hairpin RNA (shRNA) targeting BCL11A mRNA embedded in a microRNA (shmiR), allowing erythroid lineage-specific knockdown. Patients were assessed for primary end points of engraftment and safety and for hematologic and clinical responses to treatment. RESULTS: As of October 2020, six patients had been followed for at least 6 months after receiving BCH-BB694 gene therapy; median follow-up was 18 months (range, 7 to 29). All patients had engraftment, and adverse events were consistent with effects of the preparative chemotherapy. All the patients who could be fully evaluated achieved robust and stable HbF induction (percentage HbF/(F+S) at most recent follow-up, 20.4 to 41.3%), with HbF broadly distributed in red cells (F-cells 58.9 to 93.6% of untransfused red cells) and HbF per F-cell of 9.0 to 18.6 pg per cell. Clinical manifestations of sickle cell disease were reduced or absent during the follow-up period. CONCLUSIONS: This study validates BCL11A inhibition as an effective target for HbF induction and provides preliminary evidence that shmiR-based gene knockdown offers a favorable risk-benefit profile in sickle cell disease. (Funded by the National Institutes of Health; ClinicalTrials.gov number, NCT03282656).
Subject(s)
Anemia, Sickle Cell/therapy , Fetal Hemoglobin/biosynthesis , Genetic Therapy , RNA Interference , Repressor Proteins/genetics , gamma-Globins/metabolism , Adolescent , Adult , Anemia, Sickle Cell/genetics , Child , Down-Regulation , Female , Fetal Hemoglobin/genetics , Gene Knockdown Techniques , Genetic Vectors , Humans , Male , Pilot Projects , RNA, Small Interfering , Repressor Proteins/metabolism , Transplantation, Autologous , Young Adult , gamma-Globins/geneticsABSTRACT
Although gene transfer to hematopoietic stem cells (HSCs) has shown therapeutic efficacy in recent trials for several individuals with inherited disorders, transduction incompleteness of the HSC population remains a hurdle to yield a cure for all patients with reasonably low integrated vector numbers. In previous attempts at HSC selection, massive loss of transduced HSCs, contamination with non-transduced cells, or lack of applicability to large cell populations has rendered the procedures out of reach for human applications. Here, we fused codon-optimized puromycin N-acetyltransferase to herpes simplex virus thymidine kinase. When expressed from a ubiquitous promoter within a complex lentiviral vector comprising the ßAT87Q-globin gene, viral titers and therapeutic gene expression were maintained at effective levels. Complete selection and preservation of transduced HSCs were achieved after brief exposure to puromycin in the presence of MDR1 blocking agents, suggesting the procedure's suitability for human clinical applications while affording the additional safety of conditional suicide.
Subject(s)
Genetic Therapy , Hematopoietic Stem Cell Transplantation , Hematopoietic Stem Cells/metabolism , Hemoglobinopathies/genetics , Hemoglobinopathies/therapy , Transduction, Genetic , beta-Globins/genetics , ATP Binding Cassette Transporter, Subfamily B/genetics , Animals , Disease Models, Animal , Gene Expression , Gene Order , Genes, Transgenic, Suicide , Genetic Therapy/methods , Genetic Vectors/genetics , Humans , Lentivirus/genetics , Mice , Mice, Transgenic , TransgenesABSTRACT
BACKGROUND AIMS: Adoptive cell therapy employing natural killer group 2D (NKG2D) chimeric antigen receptor (CAR)-modified T cells has demonstrated preclinical efficacy in several model systems, including hematological and solid tumors. We present comprehensive data on manufacturing development and clinical production of autologous NKG2D CAR T cells for treatment of acute myeloid leukemia and multiple myeloma (ClinicalTrials.gov Identifier: NCT02203825). An NKG2D CAR was generated by fusing native full-length human NKG2D to the human CD3ζ cytoplasmic signaling domain. NKG2D naturally associates with native costimulatory molecule DAP10, effectively generating a second-generation CAR against multiple ligands upregulated during malignant transformation including MIC-A, MIC-B and the UL-16 binding proteins. METHODS: CAR T cells were infused fresh after a 9-day process wherein OKT3-activated T cells were genetically modified with replication-defective gamma-retroviral vector and expanded ex vivo for 5 days with recombinant human interleukin-2. RESULTS: Despite sizable interpatient variation in originally collected cells, release criteria, including T-cell expansion and purity (median 98%), T-cell transduction (median 66% CD8+ T cells), and functional activity against NKG2D ligand-positive cells, were met for 100% of healthy donors and patients enrolled and collected. There was minimal carryover of non-T cells, particularly malignant cells; both effector memory and central memory cells were generated, and inflammatory cytokines such as granulocyte colony-stimulating factor, RANTES, interferon-γ and tumor necrosis factor-α were selectively up-regulated. CONCLUSIONS: The process resulted in production of required cell doses for the first-in-human phase I NKG2D CAR T clinical trial and provides a robust, flexible base for further optimization of NKG2D CAR T-cell manufacturing.
Subject(s)
Immunotherapy, Adoptive , NK Cell Lectin-Like Receptor Subfamily K/metabolism , Receptors, Chimeric Antigen/metabolism , T-Lymphocytes/immunology , Cell Line, Tumor , Cell Proliferation , Clinical Trials as Topic , Cytokines/metabolism , Humans , Ligands , Phenotype , Receptors, Antigen, T-Cell/immunology , T-Lymphocytes/cytology , Transplantation, AutologousSubject(s)
Hematopoietic Stem Cell Transplantation/methods , Lymphoma, Non-Hodgkin/therapy , Megakaryocytes/transplantation , Adult , Allografts , Antigens, CD34/blood , Female , Hematopoietic Stem Cells/cytology , Humans , Male , Megakaryocytes/cytology , Middle Aged , Recovery of Function , Transplantation Conditioning/methods , Transplantation, AutologousABSTRACT
To accelerate the development of Advanced Therapy Medicinal Products (ATMPs) for patients suffering from life-threatening cancer with limited therapeutic options, regulatory approaches need to be constantly reviewed, evaluated and adjusted, as necessary. This includes utilizing science and risk-based approaches to mitigate and balance potential risks associated with early clinical research and a more flexible manufacturing paradigm. In this paper, T2EVOLVE an Innovative Medicine Initiative (IMI) consortium explores opportunities to expedite the development of CAR and TCR engineered T cell therapies in the EU by leveraging tools within the existing EU regulatory framework to facilitate an iterative and adaptive learning approach across different product versions with similar design elements or based on the same platform technology. As understanding of the linkage between product quality attributes, manufacturing processes, clinical efficacy and safety evolves through development and post licensure, opportunities are emerging to streamline regulatory submissions, optimize clinical studies and extrapolate data across product versions reducing the need to perform duplicative studies. It is worth noting that this paper is focusing on CAR- and TCR-engineered T cell therapies but the concepts may be applied more broadly to engineered cell therapy products (e.g., CAR NK cell therapy products).
Subject(s)
Cell- and Tissue-Based Therapy , Immunotherapy, Adoptive , Humans , Immunotherapy, Adoptive/adverse effects , Receptors, Antigen, T-Cell/genetics , T-LymphocytesABSTRACT
To treat unilateral limbal stem cell (LSC) deficiency, we developed cultivated autologous limbal epithelial cells (CALEC) using an innovative xenobiotic-free, serum-free, antibiotic-free, two-step manufacturing process for LSC isolation and expansion onto human amniotic membrane with rigorous quality control in a good manufacturing practices facility. Limbal biopsies were used to generate CALEC constructs, and final grafts were evaluated by noninvasive scanning microscopy and tested for viability and sterility. Cultivated cells maintained epithelial cell phenotype with colony-forming and proliferative capacities. Analysis of LSC biomarkers showed preservation of "stemness." After preclinical development, a phase 1 clinical trial enrolled five patients with unilateral LSC deficiency. Four of these patients received CALEC transplants, establishing preliminary feasibility. Clinical case histories are reported, with no primary safety events. On the basis of these results, a second recruitment phase of the trial was opened to provide longer term safety and efficacy data on more patients.
Subject(s)
Anti-Bacterial Agents , Limbal Stem Cell Deficiency , Humans , Feasibility Studies , Biopsy , Commerce , Epithelial CellsABSTRACT
Lymphodepletion (LD) or conditioning is an essential step in the application of currently used autologous and allogeneic chimeric antigen receptor T-cell (CAR-T) therapies as it maximizes engraftment, efficacy and long-term survival of CAR-T. Its main modes of action are the depletion and modulation of endogenous lymphocytes, conditioning of the microenvironment for improved CAR-T expansion and persistence, and reduction of tumor load. However, most LD regimens provide a broad and fairly unspecific suppression of T-cells as well as other hematopoietic cells, which can also lead to severe side effects, particularly infections. We reviewed 1271 published studies (2011-2023) with regard to current LD strategies for approved anti-CD19 CAR-T products for large B cell lymphoma (LBCL). Fludarabine (Flu) and cyclophosphamide (Cy) (alone or in combination) were the most commonly used agents. A large number of different schemes and combinations have been reported. In the respective schemes, doses of Flu and Cy (range 75-120mg/m2 and 750-1.500mg/m2) and wash out times (range 2-5 days) differed substantially. Furthermore, combinations with other agents such as bendamustine (benda), busulfan or alemtuzumab (for allogeneic CAR-T) were described. This diversity creates a challenge but also an opportunity to investigate the impact of LD on cellular kinetics and clinical outcomes of CAR-T. Only 21 studies explicitly investigated in more detail the influence of LD on safety and efficacy. As Flu and Cy can potentially impact both the in vivo activity and toxicity of CAR-T, a more detailed analysis of LD outcomes will be needed before we are able to fully assess its impact on different T-cell subsets within the CAR-T product. The T2EVOLVE consortium propagates a strategic investigation of LD protocols for the development of optimized conditioning regimens.
Subject(s)
Receptors, Chimeric Antigen , Receptors, Chimeric Antigen/genetics , Adaptor Proteins, Signal Transducing , Alemtuzumab , Antibodies , Cyclophosphamide , Cell- and Tissue-Based TherapyABSTRACT
The annual "Antibody Industrial Symposium", co-organized by LabEx MAbImprove and MabDesign, held its 10th anniversary edition in Montpellier, France, on June 28-29, 2022. The meeting focused on new results and concepts in antibody engineering (naked, mono- or multi-specific, conjugated to drugs or radioelements) and also on new cell-based therapies, such as chimeric antigenic receptor (CAR)-T cells. The symposium, which brought together scientists from academia and industry, also addressed issues concerning the production of these molecules and cells, and the necessary steps to ensure a strong intellectual property protection of these new molecules and approaches. These two days of exchanges allowed a rich discussion among the various actors in the field of therapeutic antibodies.
Subject(s)
Antibodies, Monoclonal , Immunotherapy, Adoptive , Antibodies, Monoclonal/therapeutic use , FranceABSTRACT
Despite promising clinical results in a small subset of malignancies, therapies based on engineered chimeric antigen receptor and T-cell receptor T cells are associated with serious adverse events, including cytokine release syndrome and neurotoxicity. These toxicities are sometimes so severe that they significantly hinder the implementation of this therapeutic strategy. For a long time, existing preclinical models failed to predict severe toxicities seen in human clinical trials after engineered T-cell infusion. However, in recent years, there has been a concerted effort to develop models, including humanized mouse models, which can better recapitulate toxicities observed in patients. The Accelerating Development and Improving Access to CAR and TCR-engineered T cell therapy (T2EVOLVE) consortium is a public-private partnership directed at accelerating the preclinical development and increasing access to engineered T-cell therapy for patients with cancer. A key ambition in T2EVOLVE is to design new models and tools with higher predictive value for clinical safety and efficacy, in order to improve and accelerate the selection of lead T-cell products for clinical translation. Herein, we review existing preclinical models that are used to test the safety of engineered T cells. We will also highlight limitations of these models and propose potential measures to improve them.
Subject(s)
Immunotherapy, Adoptive , Neoplasms , Receptors, Chimeric Antigen , Animals , Cytokine Release Syndrome , Humans , Immunotherapy, Adoptive/adverse effects , Mice , Neoplasms/therapy , Receptors, Antigen, T-Cell/genetics , Receptors, Chimeric Antigen/genetics , Receptors, Chimeric Antigen/therapeutic use , T-LymphocytesABSTRACT
The subpopulation of regulatory T cells (Treg) was shown to play a key role in alloreactive responses. In allogeneic hematopoietic stem cell transplantation, several groups tested whether Treg content in transplants correlates with graft-versus-host disease (GVHD) with controversial results. In a retrospective study of 49 consecutive HLA-matched sibling transplantations, we studied the relationship between Treg content in bone marrow transplants and acute GVHD (aGVHD) occurrence. We observed a large variability in Treg in bone marrow grafts. However, contrary to previous observations in peripheral blood stem cells transplantation, we report that the Treg content of allogeneic bone marrow transplantation did not predict the occurrence of aGVHD.
Subject(s)
Bone Marrow Cells , Bone Marrow Transplantation/adverse effects , Graft Survival , Graft vs Host Disease/epidemiology , Hematopoietic Stem Cell Transplantation/adverse effects , T-Lymphocytes, Regulatory , Acute Disease , Adolescent , Adult , CD4 Antigens/metabolism , Cell Count , Female , Histocompatibility , Humans , Incidence , Male , Middle Aged , Retrospective Studies , Siblings , Young AdultABSTRACT
BACKGROUND: Allogeneic donor natural killer (NK)-cell infusion (NK-DLI) is a promising immunotherapy for patients with hematologic disorders. CASE REPORT: This report describes the case of a patient who received a single haploidentical NK-DLI for a relapse of acute myeloid leukemia (AML) after haploidentical hematopoietic stem cell transplantation. He underwent a cytoreductive, immunosuppressive regimen before NK-DLI and received high-dose interleukin-2 in vivo for 8 weeks afterward. RESULTS: No major adverse effect was observed. Prospective phenotypic and functional studies of the NK cells showed major expansion of infused NK cells and, more importantly, of the alloreactive KIR2DL1+KIR2DL2/DL3-NKG2A- subset, which reached 117×10(6) cells/L on Day +14 after NK-DLI, the greatest expansion of infused alloreactive NK cells reported so far. Infused NK cells conserved their lytic capacities against K562 target cells and primary AML-mismatched blasts. CONCLUSION: We review the literature to clarify these data and to detail the indications for allogeneic NK-DLI, the criteria for determining the most suitable donor, the types of conditioning regimens, and the procedures for selecting and activating NK cells.
Subject(s)
Hematopoietic Stem Cell Transplantation , Killer Cells, Natural/transplantation , Leukemia, Myeloid, Acute/therapy , Adult , Hematopoietic Stem Cell Transplantation/methods , Histocompatibility Testing , Humans , Immunotherapy, Adoptive/methods , K562 Cells , Leukemia, Myeloid, Acute/immunology , Male , Recurrence , Transplantation, HomologousABSTRACT
BACKGROUND: Some patients demonstrate delayed recoveries after autologous hematopoietic stem cell transplantation despite infusion of an adequate number of CD34+ cells/kg and clinically stable status. Factors considered being possible predictors of this outcome in this context were explored. STUDY DESIGN AND METHODS: A total of 246 patients were evaluated in terms of engraftment. Delayed recovery was defined by white blood cell recovery time exceeding mean+1 SEM. Clinical factors and graft characteristics were examined. Comparisons between patients with normal or delayed engraftment were made. Proinflammatory cytokines and proteolytic enzyme quantification and CXCR4+ and CD44+ cell enumeration were performed on peripheral hematopoietic stem cells (PHSC) product samples of patients with delayed engraftment and patients with usual engraftment time. RESULTS: Sixteen patients, who received at least 3 × 10(6) CD34+ cells/kg without known clinical factors likely to affect engraftment, demonstrated a delayed recovery time of over 20 days. Some graft variables were found to be significantly increased in these patients by univariate analysis. One variable was the total number of nucleated cells cryopreserved and infused. Among the nucleated cells, the absolute number of granulocytes before and after cryopreservation also differed significantly between the two groups. A multivariate analysis showed that the main predictive factor for delayed recovery was the number of nucleated cells in the graft (p=0.0044). The influence of contaminating cells might be related to the release of elastase, matrix metalloproteinase-9, interleukin (IL)-1ß, and IL-6 involved in stem cell homing. CONCLUSION: Therefore, the numeration of total nucleated cells and granulocytes should be considered as a possible quality control variable of PHSCs submitted for cryopreservation.
Subject(s)
Delayed Graft Function/etiology , Graft Survival/physiology , Hematopoietic Stem Cell Transplantation , Leukocyte Count , Leukocytes/physiology , Adult , Aged , Antigens, CD34/metabolism , Delayed Graft Function/blood , Female , Graft Survival/immunology , Hematopoietic Stem Cells/cytology , Hematopoietic Stem Cells/physiology , Humans , Leukocyte Transfusion , Leukocytes/cytology , Leukocytes/metabolism , Male , Middle Aged , Recovery of Function/immunology , Recovery of Function/physiology , Transplantation, Autologous/rehabilitationABSTRACT
Since the first genetically-engineered clinical trial was posted to clinicaltrials.gov in 2003 (NCT00019136), chimeric antigen receptor (CAR) and T-cell receptor (TCR) therapies have exhibited unprecedented growth. USA, China, and Europe have emerged as major sites of investigation as many new biotechnology and established pharmaceutical companies invest in this rapidly evolving field. Although initial studies focused primarily on CD19 as a target antigen, many novel targets are now being evaluated. Next-generation genetic constructs, starting materials, and manufacturing strategies are also being applied to enhance efficacy and safety and to treat solid tumors as well as hematologic malignancies. Fueled by dramatic clinical efficacy and recent regulatory approvals of CD19-targeted CAR cell therapies, the field of engineered cell therapeutics continues to expand. Here, we review all 745 genetically modified CAR and TCR clinical trials with anticipated accrual of over 28,000 patients posted to clinicaltrials.gov until 31st of December 2019. We analyze projected patient enrollment, geographic distribution and phase of studies, target antigens and diseases, current strategies for optimizing efficacy and safety, and trials expected to yield important clinical data in the coming 6-12 months.
Subject(s)
Genetic Therapy , Immunotherapy, Adoptive , Neoplasms/therapy , Receptors, Chimeric Antigen/genetics , T-Lymphocytes/transplantation , Clinical Trials as Topic , Humans , Neoplasms/genetics , Neoplasms/immunology , Neoplasms/metabolism , Receptors, Chimeric Antigen/metabolism , T-Lymphocytes/immunology , T-Lymphocytes/metabolism , Treatment OutcomeABSTRACT
In this work we provide preclinical data to support initiation of a first-in-human trial for sickle cell disease (SCD) using an approach that relies on reversal of the developmental fetal-to-adult hemoglobin switch. Erythroid-specific knockdown of BCL11A via a lentiviral-encoded microRNA-adapted short hairpin RNA (shRNAmiR) leads to reactivation of the gamma-globin gene while simultaneously reducing expression of the pathogenic adult sickle ß-globin. We generated a refined lentiviral vector (LVV) BCH-BB694 that was developed to overcome poor vector titers observed in the manufacturing scale-up of the original research-grade LVV. Healthy or sickle cell donor CD34+ cells transduced with Good Manufacturing Practices (GMP)-grade BCH-BB694 LVV achieved high vector copy numbers (VCNs) >5 and gene marking of >80%, resulting in a 3- to 5-fold induction of fetal hemoglobin (HbF) compared with mock-transduced cells without affecting growth, differentiation, and engraftment of gene-modified cells in vitro or in vivo. In vitro immortalization assays, which are designed to measure vector-mediated genotoxicity, showed no increased immortalization compared with mock-transduced cells. Together these data demonstrate that BCH-BB694 LVV is non-toxic and efficacious in preclinical studies, and can be generated at a clinically relevant scale in a GMP setting at high titer to support clinical testing for the treatment of SCD.
ABSTRACT
Cytotoxic chemotherapy is ineffective in metastatic renal cancer. However, systemic administration of interleukin 2 (IL-2) or infusion of dendritic cells (DCs) loaded with tumor extracts can lead to some response rates with concomitant survival improvements. We report the results of a phase I-II pilot study combining DCs and IL-2 where six patients were included. DCs were derived from bone marrow CD34+ cells and loaded with autologous tumor extracts. CD34-DC vaccines were infused subcutaneously at day 45, 52, 59, 90 and 120 following surgery in combination with IL-2, that was subsequently administrated after the 3rd and 4th DC vaccinations. Preparation of tumor extracts and CD34-DCs were satisfactory in all patients but one. Due to rapid tumor progression, one patient was excluded before vaccination. In the 4 remaining patients, two received 3 vaccinations, while the 2 others received 5 vaccinations and the full IL-2 treatment. No adverse effect due to the vaccinations was observed. A specific immune response against autologous tumor cells was observed in the 2 patients who completed the treatment. Interestingly, these 2 patients had a more prolonged survival than the patients receiving 3 vaccinations. Importantly, a transient and massive increase of circulating natural regulatory T-cells (nTregs) was evidenced in 3 patients following IL-2 administration. Overall, the use of CD34-DC vaccines is feasible, safe and non-toxic. A specific anti-tumor immune response can be detected. However, our data highlights that IL-2 is a potent inducer of nTregs in vivo and as such may have a negative impact on cancer immunotherapy.
Subject(s)
Antineoplastic Agents/therapeutic use , Cancer Vaccines/therapeutic use , Carcinoma, Renal Cell/therapy , Interleukin-2/therapeutic use , Kidney Neoplasms/therapy , T-Lymphocytes, Regulatory/immunology , Adult , Aged , Antigens, CD34/immunology , Antigens, Neoplasm/immunology , Cancer Vaccines/immunology , Carcinoma, Renal Cell/immunology , Dendritic Cells/immunology , Female , Humans , Immunophenotyping , Immunotherapy/methods , Kidney Neoplasms/immunology , Male , Middle Aged , T-Lymphocytes, Regulatory/drug effectsABSTRACT
OBJECTIVE: Mixed cryoglobulinemia (MC) vasculitis is an autoimmune disorder associated with chronic hepatitis C virus (HCV) infection. We previously reported that MC vasculitis is associated with a quantitative defect of peripheral blood regulatory T cells. The aim of this study was to prospectively evaluate the evolution of this defect during the course of antiviral treatment. METHODS: Treg cell frequencies and numbers were analyzed in 131 patients with chronic HCV infection (including 66 with MC vasculitis) and 20 healthy volunteer donors. Measurements were taken before, during, and after treatment with PEGylated interferon alfa-2b plus ribavirin. RESULTS: At baseline, patients with MC vasculitis had a significantly lower frequency and number of Treg cells than did patients without MC vasculitis. Complete remission of MC vasculitis following antiviral treatment was associated with a significant increase in Treg cell levels compared with baseline. In contrast, Treg cell levels in nonresponders or partial responders, which did not differ from those in complete responders at baseline, remained unchanged over the course of the study. CONCLUSION: The strong positive correlation between clinical responses and Treg cell levels provides further support for the central role of Treg cells in the pathogenesis of HCV-induced MC vasculitis and emphasizes the dual role of Treg cells in chronic HCV infection: while Treg cells may hinder viral elimination, they also limit autoimmune injury.
Subject(s)
Cryoglobulinemia/drug therapy , Hepacivirus/immunology , Hepatitis C, Chronic/drug therapy , Interferon-alpha/therapeutic use , Ribavirin/therapeutic use , T-Lymphocytes, Regulatory/immunology , Vasculitis/drug therapy , Adult , Aged , Aged, 80 and over , Antiviral Agents/therapeutic use , Cell Count , Cryoglobulinemia/complications , Cryoglobulinemia/immunology , Cryoglobulinemia/virology , Drug Therapy, Combination , Female , Flow Cytometry , Forkhead Transcription Factors/immunology , Hepatitis C, Chronic/complications , Hepatitis C, Chronic/immunology , Hepatitis C, Chronic/virology , Humans , Interferon alpha-2 , Male , Middle Aged , Recombinant Proteins , Remission Induction , Statistics, Nonparametric , T-Lymphocytes, Regulatory/cytology , Treatment Outcome , Vasculitis/complications , Vasculitis/immunology , Vasculitis/virologyABSTRACT
NKG2D ligands are widely expressed in solid and hematologic malignancies but absent or poorly expressed on healthy tissues. We conducted a phase I dose-escalation study to evaluate the safety and feasibility of a single infusion of NKG2D-chimeric antigen receptor (CAR) T cells, without lymphodepleting conditioning in subjects with acute myeloid leukemia/myelodysplastic syndrome or relapsed/refractory multiple myeloma. Autologous T cells were transfected with a γ-retroviral vector encoding a CAR fusing human NKG2D with the CD3ζ signaling domain. Four dose levels (1 × 106-3 × 107 total viable T cells) were evaluated. Twelve subjects were infused [7 acute myeloid leukemia (AML) and 5 multiple myeloma]. NKG2D-CAR products demonstrated a median 75% vector-driven NKG2D expression on CD3+ T cells. No dose-limiting toxicities, cytokine release syndrome, or CAR T cell-related neurotoxicity was observed. No significant autoimmune reactions were noted, and none of the ≥ grade 3 adverse events were attributable to NKG2D-CAR T cells. At the single injection of low cell doses used in this trial, no objective tumor responses were observed. However, hematologic parameters transiently improved in one subject with AML at the highest dose, and cases of disease stability without further therapy or on subsequent treatments were noted. At 24 hours, the cytokine RANTES increased a median of 1.9-fold among all subjects and 5.8-fold among six AML patients. Consistent with preclinical studies, NKG2D-CAR T cell-expansion and persistence were limited. Manufactured NKG2D-CAR T cells exhibited functional activity against autologous tumor cells in vitro, but modifications to enhance CAR T-cell expansion and target density may be needed to boost clinical activity.
Subject(s)
Immunotherapy, Adoptive , Leukemia, Myeloid, Acute/therapy , Multiple Myeloma/therapy , Myelodysplastic Syndromes/therapy , Adult , Aged , Cytokines/immunology , Female , Humans , Ligands , Male , Middle Aged , NK Cell Lectin-Like Receptor Subfamily K/genetics , NK Cell Lectin-Like Receptor Subfamily K/immunology , Receptors, Chimeric Antigen/immunology , T-Lymphocytes/immunologyABSTRACT
Novel therapies for sickle cell disease (SCD) based on genetically engineered autologous hematopoietic stem and progenitor cells (HSPCs) are critically dependent on a safe and effective strategy for cell procurement. We sought to assess the safety and efficacy of plerixafor when used in transfused patients with SCD for HSC mobilization. Six adult patients with SCD were recruited to receive a single dose of plerixafor, tested at lower than standard (180 µg/kg) and standard (240 µg/kg) doses, followed by CD34+ cell monitoring in peripheral blood and apheresis collection. The procedures were safe and well-tolerated. Mobilization was successful, with higher peripheral CD34+ cell counts in the standard vs the low-dose group. Among our 6 donors, we improved apheresis cell collection results by using a deep collection interface and starting apheresis within 4 hours after plerixafor administration. In the subjects who received a single standard dose of plerixafor and followed the optimized collection protocol, yields of up to 24.5 × 106 CD34+ cells/kg were achieved. Interestingly, the collected CD34+ cells were enriched in immunophenotypically defined long-term HSCs and early progenitors. Thus, we demonstrate that plerixafor can be employed safely in patients with SCD to obtain sufficient HSCs for potential use in gene therapy.