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2.
Brain Behav Immun Health ; 23: 100480, 2022 Aug.
Article En | MEDLINE | ID: mdl-35757656

Inflammatory physiology has been linked to behavioral and emotional symptoms in a variety of contexts and experimental paradigms. Hematopoietic cell transplantation (HCT) represents an intersection of significant immune dysregulation and psychosocial stress, and this biobehavioral relationship can influence important clinical outcomes. For those undergoing HCT with inflammation-related neuropsychiatric symptoms, using targeted agents such as the IL-6 receptor antagonist tocilizumab may be an effective therapeutic approach. We conducted an observational cohort study to explore patient reported outcomes (PROs) and inflammatory biomarkers among allogeneic HCT recipients who received tocilizumab compared to those who did not. Individuals on a larger trial of tocilizumab for prevention of graft-versus-host disease received a single dose of tocilizumab 24 h prior to stem cell infusion. Measures of anxiety, depression, pain, fatigue, and sleep quality and parallel blood samples for inflammatory cytokines were collected from participants and an analogous comparison cohort at baseline and Day 28 after stem cell infusion. Demographic and medical characteristics were reported; an analysis of covariance regression model was fitted to evaluate differences in PROs and distance correlation t-tests assessed for associations between biomarkers and PRO measures. For n = 18 tocilizumab-treated and n = 22 comparison patients, there were no significant differences between patient demographics, but the tocilizumab cohort had a different distribution of primary diagnoses (p = 0.009) with more patients with leukemias and a higher proportion of patients in their first remission (64% vs 28%, p = 0.024). Depression was higher at Day 28 compared to baseline in both groups (comparison group: +5.1 [95% CI 0.14-10, p = 0.045], tocilizumab: +8.6 [95% CI 2.3-15, p = 0.011]), though the difference between groups did not reach statistical significance. The tocilizumab group had significantly increased circulating IL-6 and decreased CRP at Day 28 (all p < 0.05). There was an association between collective baseline biomarkers and PROs (distance correlation dCor = 0.110, p = 0.005), but this same association was not present at Day 28 (dCor = -0.001, p = 0.5). In univariate analyses, a 10-fold increase in plasma IL-6 was associated with a 3.6-point higher depression score (95% CI 1.0-6.2, p = 0.008). In this exploratory analysis of PROs and inflammatory biomarkers in patients undergoing HCT, tocilizumab was not associated with favorable patient-reported symptom profiles. This finding is aligned with our prior work in the HCT population but diverges from hypothesized therapeutic effects of tocilizumab on depressive symptoms, thus highlighting the need for larger prospective translational studies in biobehavioral HCT research.

4.
Nat Med ; 26(10): 1569-1575, 2020 10.
Article En | MEDLINE | ID: mdl-33020647

Chimeric antigen receptor (CAR) T cells targeting CD19 are a breakthrough treatment for relapsed, refractory B cell malignancies1-5. Despite impressive outcomes, relapse with CD19- disease remains a challenge. We address this limitation through a first-in-human trial of bispecific anti-CD20, anti-CD19 (LV20.19) CAR T cells for relapsed, refractory B cell malignancies. Adult patients with B cell non-Hodgkin lymphoma or chronic lymphocytic leukemia were treated on a phase 1 dose escalation and expansion trial (NCT03019055) to evaluate the safety of 4-1BB-CD3ζ LV20.19 CAR T cells and the feasibility of on-site manufacturing using the CliniMACS Prodigy system. CAR T cell doses ranged from 2.5 × 105-2.5 × 106 cells per kg. Cell manufacturing was set at 14 d with the goal of infusing non-cryopreserved LV20.19 CAR T cells. The target dose of LV20.19 CAR T cells was met in all CAR-naive patients, and 22 patients received LV20.19 CAR T cells on protocol. In the absence of dose-limiting toxicity, a dose of 2.5 × 106 cells per kg was chosen for expansion. Grade 3-4 cytokine release syndrome occurred in one (5%) patient, and grade 3-4 neurotoxicity occurred in three (14%) patients. Eighteen (82%) patients achieved an overall response at day 28, 14 (64%) had a complete response, and 4 (18%) had a partial response. The overall response rate to the dose of 2.5 × 106 cells per kg with non-cryopreserved infusion (n = 12) was 100% (complete response, 92%; partial response, 8%). Notably, loss of the CD19 antigen was not seen in patients who relapsed or experienced treatment failure. In conclusion, on-site manufacturing and infusion of non-cryopreserved LV20.19 CAR T cells were feasible and therapeutically safe, showing low toxicity and high efficacy. Bispecific CARs may improve clinical responses by mitigating target antigen downregulation as a mechanism of relapse.


Antigens, CD19/immunology , Antigens, CD20/immunology , Immunotherapy, Adoptive/methods , Leukemia, B-Cell/therapy , Lymphoma, B-Cell/therapy , Adult , Aged , Dose-Response Relationship, Immunologic , Female , Humans , Leukemia, B-Cell/immunology , Leukemia, B-Cell/pathology , Lymphocyte Count , Lymphoma, B-Cell/immunology , Lymphoma, B-Cell/pathology , Male , Middle Aged , Receptors, Antigen, T-Cell/immunology , Receptors, Chimeric Antigen/immunology , Recurrence , T-Lymphocytes/cytology , T-Lymphocytes/immunology , T-Lymphocytes/metabolism , T-Lymphocytes/transplantation
5.
Biol Blood Marrow Transplant ; 26(10): 1876-1885, 2020 10.
Article En | MEDLINE | ID: mdl-32653622

Chronic graft-versus-host disease (cGVHD) is major cause of morbidity and mortality following allogeneic hematopoietic cell transplantation (HCT). Ixazomib is an oral, second-generation, proteasome inhibitor that has been shown in preclinical models to prevent GVHD. We conducted a phase I/II trial in 57 patients to evaluate the safety and efficacy of ixazomib administration for cGVHD prophylaxis in patients undergoing allogeneic HCT. Oral ixazomib was administered on a weekly basis for a total of 4 doses, beginning days +60 through +90, to recipients of matched related donor (MRD, n = 25) or matched unrelated donor (MUD, n = 26) allogeneic HCT in phase II portion of the study, once the recommended phase II dose of 4 mg was identified in phase I (n = 6). All patients received peripheral blood graft and standard GVHD prophylaxis of tacrolimus and methotrexate. Ixazomib administration was safe and well tolerated, with thrombocytopenia, leukopenia, gastrointestinal complaints, and fatigue the most common adverse events (>10%). In phase II (n = 51), the cumulative incidence of cGVHD at 1 year was 36% (95% confidence interval [CI], 19% to 54%) in the MRD cohort and 39% (95% CI, 21% to 56%) in the MUD cohort. One-year cumulative incidence of nonrelapse mortality (NRM) and relapse was 0% and 20% (95% CI, 8% to 36%) in the MRD cohort, respectively. In the MUD cohort, the respective NRM and relapse rates were 4% (0% to 16%) and 34% (17% to 52%). The outcomes on the study were compared post hoc with contemporaneous matched Center for International Blood and Marrow Transplant Research (CIBMTR) controls. This post hoc analysis showed no significant improvement in cGVHD rates in both the MRD (hazard ratio [HR] = 0.85, P = .64) or MUD cohorts (HR = 0.68, P = .26) on the study compared with CIBMTR controls. B cell activating factor plasma levels were significantly higher after ixazomib dosing in those who remained cGVHD free compared with those developed cGVHD. This study shows that the novel strategy of short-course oral ixazomib following allogeneic HCT is safe but did not demonstrate significant improvement in cGVHD incidence in recipients of MRD and MUD transplantation compared with matched CIBMTR controls. This study is registered at www.clinicaltrials.gov as NCT02250300.


Graft vs Host Disease , Hematopoietic Stem Cell Transplantation , Boron Compounds , Chronic Disease , Glycine/analogs & derivatives , Glycine/therapeutic use , Graft vs Host Disease/prevention & control , Humans , Tacrolimus , Transplantation Conditioning
6.
Haematologica ; 103(4): 717-727, 2018 04.
Article En | MEDLINE | ID: mdl-29351985

We conducted a phase 2 study in which patients undergoing allogeneic hematopoietic stem cell transplantation received tocilizumab in addition to standard immune suppression with tacrolimus and methotrexate for graft-versus-host disease prophylaxis. Thirty-five patients were enrolled between January 2015 and June 2016. The median age of the cohort was 66 (range: 22-76). All patients received busulfan-based conditioning, and were transplanted with human leukocyte antigen-matched related or matched unrelated bone marrow or peripheral stem cell grafts. The cumulative incidences of grades II-IV and III-IV acute graft-versus-host disease were 14% (95% CI 5-30) and 3% (95% CI 0-11) at day 100, and 17% (95% CI 7-31) and 6% (95% CI 1-16) at day 180, respectively. Notably, there were no cases of graft-versus-host disease of the lower gastrointestinal tract within the first 100 days. A comparison to 130 matched controls who only received tacrolimus and methotrexate demonstrated a lower cumulative incidence of grades II-IV acute graft-versus-host disease (17% versus 45%, P=0.003) and a significant increase in grades II-IV acute graft-versus-host disease-free survival at six months (69% versus 42%, P=0.001) with tocilizumab, tacrolimus and methotrexate, which was the primary endpoint of the study. Immune reconstitution was preserved in patients treated with tocilizumab, tacrolimus and methotrexate, as T-cell and B-cell subsets recovered to near normal levels by 6-12 months post-transplantation. We conclude that tocilizumab has promising activity in preventing acute graft-versus-host disease, particularly in the lower gastrointestinal tract, and warrants examination in a randomized setting.


Drug Therapy, Combination/methods , Gastrointestinal Diseases/drug therapy , Graft vs Host Disease/prevention & control , Immunosuppressive Agents/therapeutic use , Adult , Aged , Antibodies, Monoclonal, Humanized/therapeutic use , Female , Graft Survival/drug effects , Graft vs Host Disease/drug therapy , Hematopoietic Stem Cell Transplantation/adverse effects , Hematopoietic Stem Cell Transplantation/methods , Humans , Incidence , Lower Gastrointestinal Tract , Male , Methotrexate/therapeutic use , Middle Aged , Tacrolimus/therapeutic use , Transplantation Conditioning/methods , Young Adult
7.
Cytotherapy ; 20(3): 394-406, 2018 03.
Article En | MEDLINE | ID: mdl-29287970

BACKGROUND AIMS: Multiple steps are required to produce chimeric antigen receptor (CAR)-T cells, involving subset enrichment or depletion, activation, gene transduction and expansion. Open processing steps that increase risk of contamination and production failure are required. This complex process requires skilled personnel and costly clean-room facilities and infrastructure. Simplified, reproducible CAR-T-cell manufacturing with reduced labor intensity within a closed-system is highly desirable for increased availability for patients. METHODS: The CliniMACS Prodigy with TCT process software and the TS520 tubing set that allows closed-system processing for cell enrichment, transduction, washing and expansion was used. We used MACS-CD4 and CD8-MicroBeads for enrichment, TransAct CD3/CD28 reagent for activation, lentiviral CD8 TM-41BB-CD3 ζ-cfrag vectors expressing scFv for CD19 or CD20/CD19 antigens for transduction, TexMACS medium-3%-HS-IL2 for culture and phosphate-buffered saline/ethylenediaminetetraacetic acid buffer for washing. Processing time was 13 days. RESULTS: Enrichment (N = 7) resulted in CD4/CD8 purity of 98 ± 4.0%, 55 ± 6% recovery and CD3+ T-cell purity of 89 ± 10%. Vectors at multiplicity of infection 5-10 resulted in transduction averaging 37%. An average 30-fold expansion of 108 CD4/CD8-enriched cells resulted in sufficient transduced T cells for clinical use. CAR-T cells were 82-100% CD3+ with a mix of CD4+ and CD8+ cells that primarily expressed an effector-memory or central-memory phenotype. Functional testing demonstrated recognition of B-cells and for the CAR-20/19 T cells, CD19 and CD20 single transfectants were recognized in cytotoxic T lymphocyte and interferon-γ production assays. DISCUSSION: The CliniMACS Prodigy device, tubing set TS520 and TCT software allow CAR-T cells to be manufactured in a closed system at the treatment site without need for clean-room facilities and related infrastructure.


Antigens, CD19/metabolism , Cytological Techniques/instrumentation , Receptors, Antigen, T-Cell/immunology , Receptors, Chimeric Antigen/metabolism , T-Lymphocytes/metabolism , Academic Medical Centers , Antigens, CD19/genetics , Antigens, CD19/immunology , Antigens, CD20/genetics , Antigens, CD20/immunology , Antigens, CD20/metabolism , B-Lymphocytes/immunology , CD28 Antigens/immunology , CD28 Antigens/metabolism , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/metabolism , CD8-Positive T-Lymphocytes/immunology , Cell Line , Cytological Techniques/methods , Humans , Immunophenotyping , Receptors, Antigen, T-Cell/metabolism , T-Lymphocytes/immunology , T-Lymphocytes, Cytotoxic/immunology , Transduction, Genetic
8.
J Clin Invest ; 126(9): 3541-55, 2016 09 01.
Article En | MEDLINE | ID: mdl-27500496

Damage to the gastrointestinal tract is a major cause of morbidity and mortality in graft-versus-host disease (GVHD) and is attributable to T cell-mediated inflammation. In this work, we identified a unique CD4+ T cell population that constitutively expresses the ß2 integrin CD11c and displays a biased central memory phenotype and memory T cell transcriptional profile, innate-like properties, and increased expression of the gut-homing molecules α4ß7 and CCR9. Using several complementary murine GVHD models, we determined that adoptive transfer and early accumulation of ß2 integrin-expressing CD4+ T cells in the gastrointestinal tract initiated Th1-mediated proinflammatory cytokine production, augmented pathological damage in the colon, and increased mortality. The pathogenic effect of this CD4+ T cell population critically depended on coexpression of the IL-23 receptor, which was required for maximal inflammatory effects. Non-Foxp3-expressing CD4+ T cells produced IL-10, which regulated colonic inflammation and attenuated lethality in the absence of functional CD4+Foxp3+ T cells. Thus, the coordinate expression of CD11c and the IL-23 receptor defines an IL-10-regulated, colitogenic memory CD4+ T cell subset that is poised to initiate inflammation when there is loss of tolerance and breakdown of mucosal barriers.


CD4-Positive T-Lymphocytes/cytology , Gastrointestinal Tract/immunology , Graft vs Host Disease/immunology , Immunologic Memory , Adoptive Transfer , Animals , Bone Marrow Cells/metabolism , CD11b Antigen/metabolism , CD11c Antigen/metabolism , CD18 Antigens/metabolism , Cell Proliferation , Cell Separation , Cytokines/metabolism , Disease Models, Animal , Flow Cytometry , Forkhead Transcription Factors/metabolism , Humans , Immunoassay , Inflammation , Interleukin-10/metabolism , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Phenotype , Receptors, Interleukin/metabolism
9.
Cytotherapy ; 17(12): 1813-9, 2015 Dec.
Article En | MEDLINE | ID: mdl-26454752

BACKGROUND AIMS: Removing DMSO post-thaw results in: reduced infusion reactions, improved recovery and stability of viable CD34+ cells. Validated methods use 5%-8.3% Dextran 40 with 2.5%-4.2% HSA for this purpose. Recent shortages of clinical grade Dextran require identification of suitable alternatives. METHODS: PBPC were used to compare a standard 2X wash medium of 5 parts 10% Dextran 40 in saline (DEX) with 1 part 25% HSA (8.3% DEX/ 4.2% HSA) with Hydroxyethyl Starch (HES)-based solutions. Cells in replicate bags were diluted with an equal volume of wash solution, equilibrated 5 minutes, the bag filled with wash medium, pelleted and the supernatant expressed. Bags were restored to the frozen volume in wash medium and tested by single platform flow cytometry and CFU. Total viability, viable TNC, MNC, and CD34+ cell recovery, and CD34+ cell viability were compared immediately post-thaw and after 90 minutes. RESULTS: 5.2% HES/4.2% HSA did not differ from our standard in CD34 recovery or viability. Due to concerns that high concentrations of HES could affect renal function we tested 0.6% HES/2.5% HSA resulting in significantly poorer CD34 recovery and viability. Results improved using 2.4% HES/4.2% HSA and when 0.6% HES/4.2%HSA was used no significant differences were seen. CFU assays confirmed no differences between the standard dextran arm and HES at 2.4% or 0.6% so long as HSA was at 4.2%. CONCLUSIONS: We conclude that HES from 0.6% to 5.2% with 4.2% HSA is a suitable substitute for Dextran 40 as a reconstitution/washing medium for PBPC products.


Cryopreservation/methods , Dextrans/pharmacology , Hematopoietic Stem Cells/cytology , Hydroxyethyl Starch Derivatives/pharmacology , Cell Survival/drug effects , Cells, Cultured , Colony-Forming Units Assay , Culture Media , Freezing , Humans , Male
10.
J Gen Virol ; 91(Pt 6): 1577-89, 2010 Jun.
Article En | MEDLINE | ID: mdl-20130135

Many of the 51 serotypes of adenovirus have been associated with clinically relevant infection. Adenovirus can disseminate rapidly in patients with a compromised immune system, such as that which occurs secondary to haematopoietic progenitor-cell transplantation. The higher rate of infection in recipients of T cell-depleted grafts and in those undergoing T cell-targeted treatment during graft versus host disease demonstrates the importance of a T-cell response in preventing disseminated infection. Studies have shown that the memory response to adenovirus is directed primarily to the hexon protein and is dominated by CD4+ T cells, probably due to the ability of the virus to block its presentation on HLA class I antigens. We have developed an approach to expand adenovirus-specific T cells using a pool of overlapping pentadecapeptides derived from selected conserved regions of hexon. We characterized responses to identify the peptides that are recognized, the responding T-cell subsets and their HLA restriction. Of eight lines that were characterized extensively, seven included both CD4+ and CD8+ T cells and each recognized between two and eight unique peptide sequences. By focusing the response on the conserved sequences of hexon, the cell lines are likely to recognize most of the serotypes responsible for clinically relevant disease. The 15 aa peptides used to prime the responses are more likely than whole virus or longer peptides to expand the less frequent CD8+ memory subset. Lines prepared by using our method may be more effective in adoptive immunotherapy protocols designed to prevent or treat disseminated adenovirus infections in high-risk patients.


Adenoviruses, Human/immunology , Capsid Proteins/immunology , T-Lymphocytes, Cytotoxic/immunology , Adenoviridae Infections/therapy , Adoptive Transfer , CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , Humans , Immunocompromised Host , Oligopeptides/immunology
11.
Vaccine ; 23(27): 3572-80, 2005 May 20.
Article En | MEDLINE | ID: mdl-15855016

The premise of this work is that within a given hepatitis C virus (HCV) protein there exists an array of Th1 and Th2 epitopes, each of which can provide synergistic (positive or negative) effects upon other epitopes by intramolecular, cytokine-mediated immunoregulation of helper T-cell responses. To address this question, we constructed minigene plasmids pHCVTh1, pHCVTh1X3 and pHCVThR, and HCV NS3 full-length plasmid pHCVNS3. 293T cells were transfected with these plasmids and cell lysates from the transfected cells were used to stimulate PBMC from a patient with chronic HCV infection. IL-2 and IFN-gamma in the supernatant of the cultured PBMC were tested and proliferation of the PBMC was measured. The results demonstrate that interactions exist among helper T-cell epitopes; the synergistic effects of suppressive Th2 epitopes upon Th1 epitopes will inhibit the responses induced by Th1 epitopes, which may contribute to chronic infection by HCV; synergistic effects among Th1 epitopes induce higher levels of IFN-gamma, which may suggest a new strategy for HCV vaccine development. Further, stimulation of an HCV NS3 specific clone with cell lysates from 293T cells transfected with different constructs shows that the HCV NS3 clone could respond to all suggesting that the epitope-specific suppression may be due to an imbalance of Type 1 and Type 2 cytokines or regulatory T-cells.


Epitopes, T-Lymphocyte/immunology , Hepacivirus/immunology , Immunodominant Epitopes/immunology , T-Lymphocytes, Helper-Inducer/immunology , Amino Acid Sequence , Cell Line , Epitopes, T-Lymphocyte/genetics , Epitopes, T-Lymphocyte/metabolism , Hepacivirus/genetics , Hepacivirus/metabolism , Hepatitis C, Chronic/genetics , Hepatitis C, Chronic/immunology , Hepatitis C, Chronic/metabolism , Humans , Immunodominant Epitopes/genetics , Immunodominant Epitopes/metabolism , Lymphocyte Activation/immunology , Molecular Sequence Data , T-Lymphocytes, Helper-Inducer/metabolism , T-Lymphocytes, Helper-Inducer/virology
12.
World J Gastroenterol ; 11(7): 970-5, 2005 Feb 21.
Article En | MEDLINE | ID: mdl-15742398

AIM: To explore the pathogenicity and infectivity of hepatitis G virus (HGV) by observing replication and expression of the virus, as well as the serological and histological changes of Macaca mulatta infected with HGV genomic RNA or HGV RNA-positive serum. METHODS: Full-length HGV cDNA clone (HGVqz) was constructed and proved to be infectious, from which HGV genomic RNA was transcribed in vitro. Macaca mulatta BY1 was intra-hepatically inoculated with HGV genomic RNA, HGV RNA-positive serum from BY1 was intravenously inoculated into Macaca mulatta BM1, and then BB1 was infected with serum from BM1. Serum and liver tissue were taken regularly, and checked with RT-PCR, in situ hybridization and other immunological, serological, histological assays. RESULTS: Serum HGV RNA was detectable in all the 3 Macaca mulattas, serological and histological examinations showed the experimental animals had slightly elevated alanine transaminase (ALT) and developed HGV viremia during the infectious period. The histology, immunohis-tochemistry, and in situ hybridization in liver tissues of the inoculated animals demonstrated a very mild hepatitis with HGV antigen expression in cytoplasm of hepatocytes. RT-PCR and quantitative PCR results showed that HGV could replicate in liver. CONCLUSION: The genomic RNA from full-length HGV cDNA is infectious to the Macaca mulatta and can cause mild hepatitis. HGV RNA-positive serum, from HGV RNA inoculated Macaca mulatta, is infectious to other Macaca mulattas. Macaca mulatta is susceptible to the inoculated HGV, and therefore can be used as an experimental animal model for the studies of HGV infection and pathogenesis.


Flaviviridae Infections/pathology , Flaviviridae Infections/virology , GB virus C/genetics , Hepatitis, Viral, Animal/pathology , Hepatitis, Viral, Animal/virology , Alanine Transaminase/blood , Animals , GB virus C/immunology , GB virus C/pathogenicity , Genome, Viral , Hepatitis Antibodies/blood , Immunohistochemistry , In Situ Hybridization , Macaca mulatta , RNA, Viral/analysis , Virulence , Virus Replication
13.
Vaccine ; 23(7): 951-62, 2005 Jan 04.
Article En | MEDLINE | ID: mdl-15603898

Hepatitis C virus (HCV) causes non-A, non-B hepatitis and infects an estimated 170 million people worldwide. The treatment for HCV infection is often unsuccessful with high costs and many side-effects. There is a great need for alternative therapies including preventive and therapeutic vaccination for HCV infection. The experiments in this study were carried out to elucidate whether endogenously expressed antigen can be presented to helper T-cells restricted by class II molecules and to determine whether responses to plasmid-derived antigen resemble those that we have reported for recombinant antigens or synthetic peptides. To address these issues, a multi-epitope minigene was expressed in 293T-cells and Epstein-Barr virus (EBV)-transformed B-lymphoblastoid cells (BLCL). The transfected BLCLs were employed as APCs to stimulate epitope-specific T-cell hybridomas (THC). The results demonstrated that the endogenously expressed minigene antigens could be processed and presented to T-cell hybridomas by HLA matched BLCL. Five out of seven incorporated epitopes were recognized. Blockade of HLA DR could abolish the release of IL-2, which demonstrated that the endogenously expressed minigene antigens were presented by MHC class II molecules. The presentation of endogenously expressed antigens was much more efficient than that of exogenous antigens, at least in the present study. The findings obtained here have important significance for the development of an HCV DNA vaccine.


Antigen Presentation , B-Lymphocytes/immunology , Epitopes, B-Lymphocyte/immunology , HLA-DR4 Antigen/immunology , Hepatitis C Antigens/immunology , Herpesvirus 4, Human/immunology , Animals , Antigen Presentation/genetics , B-Lymphocytes/metabolism , Base Sequence , Cell Line , Cell Line, Transformed , Epitopes, B-Lymphocyte/genetics , Epitopes, B-Lymphocyte/metabolism , HLA-DR4 Antigen/biosynthesis , Hepatitis C Antigens/genetics , Hepatitis C Antigens/metabolism , Herpesvirus 4, Human/genetics , Humans , Mice , Mice, Transgenic , Molecular Sequence Data
14.
Sci China C Life Sci ; 46(1): 77-86, 2003 Feb.
Article En | MEDLINE | ID: mdl-20213364

Brain-derived neurotrophic factor (BDNF) shows potential in the treatment of neurodegenerative diseases, but the therapeutic application of BDNF has been greatly limited because it is too large in molecular size to permeate blood-brain barrier. To develop low-molecular-weight BDNF-like peptides, we selected a phage-displayed random peptide library using trkB expressed on NIH 3T3 cells as target in the study. With the strategy of peptide library incubation with NIH 3T3 cells and competitive elution with 1 microg/mL of BDNF in the last round of selection, the specific phages able to bind to the natural conformation of trkB and antagonize BDNF binding to trkB were enriched effectively. Five trkB-binding peptides were obtained, in which a core sequence of CRA/TXphiXXphiXXC (X represents the random amino acids, phi represents T, L or I) was identified. The BDNF-like activity of these five peptides displayed on phages was not observed, though all of them antagonized the activity of BDNF in a dose-dependent manner. Similar results were obtained with the synthetic peptide of C1 clone, indicating that the 5 phage-derived peptides were trkB antagonists. These low-molecular-weight antagonists of trkB may be of potential application in the treatment of neuroblastoma and chronic pain. Meanwhile, the obtained core sequence also could be used as the base to construct the secondary phage-displayed peptide library for further development of small peptides mimicking BDNF activity.


Carrier Proteins/metabolism , Oligopeptides/metabolism , Receptor, trkB/metabolism , Amino Acid Sequence , Animals , Brain-Derived Neurotrophic Factor/genetics , Brain-Derived Neurotrophic Factor/metabolism , Carrier Proteins/genetics , In Vitro Techniques , Mice , NIH 3T3 Cells , Oligopeptides/genetics , Peptide Library , Protein Binding , Rats , Receptor, trkB/antagonists & inhibitors , Receptor, trkB/genetics , Recombinant Proteins/genetics , Recombinant Proteins/metabolism
15.
Hum Immunol ; 63(9): 710-8, 2002 Sep.
Article En | MEDLINE | ID: mdl-12175725

Hepatitis C virus specific (HCV-specific) CD8+ cytotoxic T cells play a critical role in viral clearance. Low HCV-specific cytotoxic T lymphocyte (CTL) responses in chronic HCV infection may favor the persistence of virus, whereas stimulation and expansion of HCV-specific CTL activity may assist elimination of HCV infection. Helper T cells control the intensity of CD8+ T-cell responses and helper T-cell responses are known to be compromised in chronic carriers of HCV. In this study, we wanted to ascertain if strengthening the Th response could increase the intensity of CTL activity against HCV target antigens. We selected a synthetic CTL peptide NS3(1073-1081)), two Th1 epitopes, peptide NS3(358-375) and NS5B(155-172), and one Th2 epitope, peptide NS3(505-521). By using the four peptides alone or in combinations, we stimulated peripheral blood cells isolated from a chronic hepatitis C patient in vitro and then analyzed CD8 T cells specific for the NS3(1073-1081) CTL epitope in A2 tetramer staining and cytotoxicity assays. The results demonstrated that CTL responses could be augmented by helper T-cell epitopes NS3(358-375) and NS5B(155-172). Th2 epitope NS3(505-521) inhibited augmentation of CTL activity by Th1 epitopes. This inhibitory effect could be overcome by combining the two Th1 epitopes NS3(358-375) and NS5B(155-172) together with NS3(505-521). Under such conditions, CTL frequency was restored, but cytotoxic activity remained low suggesting that the help provided under these cultures was sufficient to drive proliferation of CTL, but not sufficient to drive differentiation into mature killer cells. These results may provide some insights into compromised CTL activity in HCV viral persistence.


Hepacivirus/immunology , T-Lymphocytes, Cytotoxic/immunology , T-Lymphocytes, Helper-Inducer/immunology , Viral Nonstructural Proteins/immunology , Amino Acid Sequence , Antigens, Viral/genetics , Epitopes/genetics , HLA-A2 Antigen/chemistry , HLA-A2 Antigen/metabolism , Hepacivirus/genetics , Hepatitis C, Chronic/immunology , Humans , In Vitro Techniques , Lymphocyte Cooperation , Molecular Sequence Data , Protein Structure, Quaternary , Th1 Cells/immunology , Th2 Cells/immunology
16.
Article En | MEDLINE | ID: mdl-12058196

VEGI(vascular endothelial cell growth inhibitor) is a novel cytokine which belongs to the TNF super-family. In this study, the VEGI gene from ECV304 cells was cloned. A truncated form of VEGI, where 23 amino acids from N-terminal were deleted and named VEGI(151), was expressed in E.coli with 25.5% of expression rate. The purity of VEGI(151) reached 92.5% after purification. VEGI(151) showed significant inhibitory effect on endothelial cells. IC(50) of VEGI151 was 10 mg/L at 24 h. At the concentration of 0.613 mg/L, VEGI(151) induced apoptosis of endothelial cells within 36 h. However, neither stimulatory effect nor inhibitory effect of VEGI(151) was detected on tumor cells(A549 HepG2 Hela)cultured in vitro. These results suggest that endothelial cells was the main target cells of VEGI(151). Our findings indicate that VEGI(151) is a potential therapeutic drug on angiogenic disease and cancer.

17.
World J Gastroenterol ; 4(2): 165-168, 1998 Apr.
Article En | MEDLINE | ID: mdl-11819265

AIM:To obtain greater antigenicity of HCV NS3 protein.METHODS:The HCV NS3 cDNA fragment was amplified by reverse transcription polymerase chain reaction from the sera of the HCV infected patients.The DNA sequence was determined by dideoxy-mediated chain termination method using T7 polymerase.HCV NS3 protein was expressed in E. coli.RESULTS:Sequence analysis indicated that the HCV isolate of this study belongs to HCV-II; SDS-PAGE demonstrated an M(r) 23800 and an M(r) 22000 recombinant protein band which amount to 14% and 11% of the total bacterial proteins separately.Western blotting and ELISA showed NS3 protein possessed greater antigenicity.CONCLUSION:Recombinant HCV NS3 protein was expressed successfully, which provided the basis for developing HCV diagnostic reagents.

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