Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 84
Filter
1.
Tech Coloproctol ; 23(6): 611, 2019 Jun.
Article in English | MEDLINE | ID: mdl-31168776

ABSTRACT

Unfortunately, the "Informed consent" statement was incorrectly published in the original version. The complete correct reference should read as follows.

2.
Tech Coloproctol ; 23(4): 325-332, 2019 Apr.
Article in English | MEDLINE | ID: mdl-31016550

ABSTRACT

BACKGROUND: The aim of the present study was to evaluate patient factors that affect the progression of anal dysplasia in human immunodeficiency virus (HIV)-positive individuals. METHODS: A retrospective cohort study of HIV-positive adults with human papilloma virus related anal lesions was performed from 2012 to 2017. All patients underwent surgical excision or biopsy and fulguration of lesions in the operating room without using high resolution anoscopy. Patients with initial presentation of squamous cell carcinoma were excluded. The study was designed to investigate progression between the first available histology and either the follow up histology or a negative examination. Patient files were reviewed and data was collected. A bivariate analysis of continuous and categorical variables was performed. RESULTS: One hundred and sixty-one patients met the inclusion criteria. Ninety-seven percent were male. Mean age was 41 years. Thirty-five percent were African American and 47% were Caucasian. After a median follow-up interval of 331 days (IQR 120-615 days) 14 (9%) of patients had progression of disease. Visible lesions on initial presentation, as opposed to lesions found  in patients undergoing examination under anesthesia because of HSIL on anal pap smear, was associated with progression (p = 0.0.2). A lower initial CD4 count (p = 0.01) and initial surgical pathology of anal condylomata (p = 0.01) were also associated with progression. High-risk serotype was associated with no change or regression (p = 0.01). CONCLUSIONS: In our large cohort of HIV-positive patients treated without high resolution anoscopy the rate of progression was low.  Most notably, visible lesions at initial presentation and CD4 count when lower were associated with progression. Initial surgical pathology of anal condylomata was associated with progression, while high-risk serotypes correlated with regression or stability. Identification of risk factors has important implications concerning postoperative surveillance and counseling of HIV-positive patients with anal condylomata/ anal dysplasia.


Subject(s)
Anus Neoplasms/pathology , Carcinoma in Situ/pathology , Carcinoma, Squamous Cell/pathology , HIV Infections/pathology , HIV , Adult , Anal Canal/pathology , Anal Canal/virology , Anus Neoplasms/virology , Biopsy , Carcinoma in Situ/virology , Carcinoma, Squamous Cell/virology , Condylomata Acuminata/pathology , Condylomata Acuminata/virology , Disease Progression , Female , HIV Infections/virology , Humans , Male , Proctoscopy , Retrospective Studies , Risk Factors
3.
J Phys Condens Matter ; 31(3): 034003, 2019 Jan 23.
Article in English | MEDLINE | ID: mdl-30524049

ABSTRACT

Understanding organic-organic interfaces is rather challenging due to their large complexity regarding morphology, molecular orientation at the interface, interdiffusion, and energetics. One additional important but often neglected aspect are chemical reactions occuring at such interfaces. For solid interfaces between pentacene and Buckminster-Fullerene (C60) recently very efficient Diels-Alder (D-A) adduct formation has been reported. Considering the importance of pentacene/C60 as prototypical donor-acceptor combination to study fundamental processes in organic photovoltaics, understanding this effect is essential. In this work, we provide detailed NEXAFS-based investigations with respect to the temperature-dependence and reaction zone depth of this effect. Moreover, we widely vary the interface morphology and observe that the D-A adduct formation is most efficient for bulk heterojunctions of pentacene and C60. By also investigating further material combinations such as PEN/C60-PCBM and interfaces between C60 and functionalized acenes, we observe trends for the occurrence of the D-A adduct formation correlated with the different chemical properties of the involved compounds.

4.
Ann Oncol ; 29(1): 200-208, 2018 01 01.
Article in English | MEDLINE | ID: mdl-29186353

ABSTRACT

Background: Reported prevalence of driver gene mutations in non-small-cell lung cancer (NSCLC) is highly variable and clinical correlations are emerging. Using NSCLC biomaterial and clinical data from the European Thoracic Oncology Platform Lungscape iBiobank, we explore the epidemiology of mutations and association to clinicopathologic features and patient outcome (relapse-free survival, time-to-relapse, overall survival). Methods: Clinically annotated, resected stage I-III NSCLC FFPE tissue was assessed for gene mutation using a microfluidics-based multiplex PCR platform. Mutant-allele detection sensitivity is >1% for most of the ∼150 (13 genes) mutations covered in the multiplex test. Results: Multiplex testing has been carried out in 2063 (76.2%) of the 2709 Lungscape cases (median follow-up 4.8 years). FFPE samples mostly date from 2005 to 2008, yet recently extracted DNA quality and quantity was generally good. Average DNA yield/case was 2.63 µg; 38 cases (1.4%) failed QC and were excluded from study; 95.1% of included cases allowed the complete panel of mutations to be tested. Most common were KRAS, MET, EGFR and PIK3CA mutations with overall prevalence of 23.0%, 6.8%, 5.4% and 4.9%, respectively. KRAS and EGFR mutations were significantly more frequent in adenocarcinomas: PIK3CA in squamous cell carcinomas. MET mutation prevalence did not differ between histology groups. EGFR mutations were found predominantly in never smokers; KRAS in current/former smokers. For all the above mutations, there was no difference in outcome between mutated and non-mutated cases. Conclusion: Archival FFPE NSCLC material is adequate for multiplex mutation analysis. In this large, predominantly European, clinically annotated stage I-III NSCLC cohort, none of the mutations characterized showed prognostic significance.


Subject(s)
Carcinoma, Non-Small-Cell Lung/genetics , Lung Neoplasms/genetics , Mutation , Adult , Aged , Aged, 80 and over , Anaplastic Lymphoma Kinase/biosynthesis , Anaplastic Lymphoma Kinase/genetics , Carcinoma, Non-Small-Cell Lung/epidemiology , Carcinoma, Non-Small-Cell Lung/pathology , DNA Mutational Analysis/methods , Female , Humans , Lung Neoplasms/epidemiology , Lung Neoplasms/pathology , Male , Middle Aged , Multiplex Polymerase Chain Reaction/methods , Neoplasm Staging , Prevalence , Progression-Free Survival , Proto-Oncogene Proteins c-met/biosynthesis , Proto-Oncogene Proteins c-met/genetics , Smoking/genetics , Young Adult
5.
AIDS Behav ; 21(1): 163-173, 2017 Jan.
Article in English | MEDLINE | ID: mdl-27460094

ABSTRACT

More than half of persons living with HIV (PLWH) do not enter into or remain in continuous HIV medical care. Disclosure of HIV serostatus to social contacts may play an important role in successful engagement of PLWH with medical care. The effect of disclosure on medical care engagement was examined in a sample of African American PLWH (n = 262) recruited from community-based organizations as part of a peer community health worker initiative. At baseline assessment, many of the PLWH (46 %) reported they had not disclosed their serostatus to others. Engagement in medical care was assessed 45 and 90 days after enrollment. Participants who disclosed their HIV status were subsequently more likely to engage in HIV medical care (78 %) than persons who did not disclose their status (66 %), an effect that was confirmed in multiple logistic regression. The findings highlight disclosure as an important predictor of engagement in HIV medical care for PLWH.


Subject(s)
HIV Infections/therapy , Patient Participation , Self Disclosure , Adult , Black or African American , Denial, Psychological , Disclosure , Female , HIV Infections/psychology , Humans , Logistic Models , Male , Middle Aged , Poverty , Social Behavior , Young Adult
6.
Oncogene ; 34(50): 6066-78, 2015 Dec 10.
Article in English | MEDLINE | ID: mdl-25798843

ABSTRACT

Although cysteine cathepsins have been identified as key regulators of cancer growth, their specific role in tumor development remains unclear. Recent studies have shown that high activity levels of tumor cathepsins are primarily a result of increased cathepsin activity in cancer-promoting tumor-associated macrophages (TAMs). To further investigate the role of cysteine cathepsin activity in normal and polarized macrophages, we established in vitro and in vivo models of macrophage differentiation and polarization and used a novel cysteine cathepsin inhibitor, GB111-NH2, to block the activity of cathepsins B, L and S. Here we show that in vitro, cysteine cathepsin inhibition yields both apoptosis and proliferation of macrophages, owing to increased oxidative stress. Proteomic analysis of cathepsin- inhibited macrophages demonstrates inhibition of autophagy, suggesting a likely cause of elevated reactive oxygen species (ROS) levels. In vivo models of mammary cancer further show that cathepsin inhibition yields TAM death owing to increased ROS levels. Strikingly, apoptosis in TAMs yields a seemingly cell non-autonomous death of neighboring cancer cells, and regression of the primary growth. These results show that cysteine cathepsin inhibitors can specifically trigger macrophage cell death and may function as an effective anticancer therapy in tumors with high levels of TAMs.


Subject(s)
Cathepsins/antagonists & inhibitors , Macrophages/physiology , Mammary Neoplasms, Experimental/drug therapy , Animals , Apoptosis , Autophagy , Cathepsins/physiology , Cell Polarity , Female , Macrophages/drug effects , Mammary Neoplasms, Experimental/metabolism , Mice , Mice, Inbred BALB C , Oxidative Stress , Reactive Oxygen Species/metabolism
7.
AIDS Behav ; 19(10): 1752-62, 2015 Oct.
Article in English | MEDLINE | ID: mdl-25645327

ABSTRACT

African American/Black (Black) women suffer disproportionately to other women from HIV. An HIV prevention intervention combining two previous evidenced-based intervention programs; "Coping with Work and Family Stress" and "Hip Hop 2 Prevent Substance Abuse and HIV", was evaluated in a diverse sample of Black women (n = 205). Study participants at ten recruitment sites were assigned non-randomly to either the intervention or comparison group and then surveyed at baseline, immediate posttest, and 6-month follow-up. General Estimating Equation modeling revealed that participants in the comparison group reported less unprotected sex at immediate post-test and the intervention group less unprotected sex at 6-month follow-up. Despite the initial drop in reported unprotected sex in the comparison group, this study suggests that an HIV risk reduction intervention tailored to address Black women's socio-cultural stress and enhance their coping may reduce their unprotected sex at 6-months.


Subject(s)
Black People/psychology , Black or African American/psychology , HIV Infections/prevention & control , Sexual Behavior , Unsafe Sex/prevention & control , Adaptation, Psychological , Adult , Counseling , Female , Follow-Up Studies , HIV Infections/ethnology , Health Promotion , Humans , Male , Middle Aged , Program Evaluation , Risk-Taking , Sexual Behavior/ethnology , Sexual Behavior/psychology , Social Environment , Substance-Related Disorders , Unsafe Sex/ethnology
8.
Mucosal Immunol ; 7(4): 869-78, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24301657

ABSTRACT

Breakdown of the epithelial barrier because of toxins or other insults leads to severe colitis. Interleukin-10 (IL-10) is a critical regulator of this, yet its cellular targets and mechanisms of action are not resolved. We address this here. Mice with a macrophage-selective deletion of IL-10Rα (IL-10Rα(Mdel)) developed markedly enhanced dextran sodium sulfate (DSS)-induced colitis that did not significantly differ from disease in IL-10(-/-) or IL-10Rα(-/-) mice; no impact of IL-10Rα deficiency in other lineages was observed. IL-10Rα(Mdel) colitis was associated with increased mucosal barrier disruption in the setting of intact epithelial regeneration. Lamina propria macrophages (LPMφs) did not show numerical or phenotypic differences from controls, or a competitive advantage over wild-type cells. Proinflammatory cytokine production, and particularly tumor necrosis factor-α (TNF-α), was increased, although TNF-α neutralization failed to reveal a defining role for this cytokine in the aggravated disease. Rather, IL-10Rα(Mdel) LPMφs produced substantially greater levels of nitric oxide (NO) and reactive oxygen species (ROS) than controls. Inhibition of these had modest effects in wild-type mice, although they dramatically reduced colitis severity in IL-10Rα(Mdel) mice, and largely eliminated the differential effect of DSS in them. Therefore, the palliative actions of IL-10 in DSS-induced colitis predominantly results from its macrophage-specific effects. Downregulation of NO and ROS production are central to the protective actions of IL-10.


Subject(s)
Colitis/immunology , Colitis/metabolism , Interleukin-10/metabolism , Macrophages/immunology , Macrophages/metabolism , Nitric Oxide/metabolism , Reactive Oxygen Species/metabolism , Animals , Colitis/chemically induced , Colitis/genetics , Colitis/pathology , Cytokines/metabolism , Dextran Sulfate/adverse effects , Disease Models, Animal , Gene Expression , Inflammation Mediators/metabolism , Interleukin-10/genetics , Interleukin-10 Receptor alpha Subunit/genetics , Interleukin-10 Receptor alpha Subunit/metabolism , Intestinal Mucosa/immunology , Intestinal Mucosa/metabolism , Intestinal Mucosa/pathology , Macrophages/pathology , Mice , Mice, Knockout
9.
Nanotechnology ; 22(12): 125702, 2011 Mar 25.
Article in English | MEDLINE | ID: mdl-21317490

ABSTRACT

The addition of carbon nanotubes (CNTs) to polymeric matrices or master batches has the potential to provide composites with novel properties. However, composites with a uniform dispersion of CNTs have proved to be difficult to manufacture, especially at an industrial scale. This paper reports on processing methods that overcome problems related to the control and reproducibility of dispersions. By using a high pressure homogenizer and a three-roll calendaring mill in combination, CNT reinforced epoxies were fabricated by mould casting with a well dispersed nanofiller content from 0.1 to 2 wt%. The influence of the nano-carbon reinforcements on toughness and electrical properties of the CNT/epoxies was studied. A substantial increase of all mechanical properties already appeared at the lowest CNT content of 0.1 wt%, but further raising the nanofiller concentration only led to moderate further changes. The most significant enhancement was obtained for fracture toughness, reaching up to 82%. The low percolation thresholds were confirmed by electrical conductivity measurements on the same composites yielding a threshold value of only about 0.01 wt%. As corroborated by a thorough microscopic analysis of the composites, mechanical and electrical enhancement points to the formation of an interconnected network of agglomerated CNTs.

10.
Oncogene ; 29(14): 2142-52, 2010 Apr 08.
Article in English | MEDLINE | ID: mdl-20101207

ABSTRACT

Adult T-cell leukemia/lymphoma is a fatal malignancy etiologically linked to infection with the human T-cell leukemia virus (HTLV-1). The virally encoded oncoprotein Tax activates the transcription of HTLV-1 and cellular genes by cooperating with cellular transcription factors. Cyclin D1 is a pivotal regulator of cell cycle progression, and increased expression strongly correlates with malignant transformation. Here, we characterize the mechanism of Tax transactivation of cyclin D1. We find that cyclin D1 transcript levels are elevated in HTLV-1 infected cells and that Tax physically associates with the cyclin D1 gene in vivo. Tax binds the cyclin D1 promoter-proximal cyclic AMP response element (CRE) in the presence of phosphorylated CREB (pCREB) in vitro, and together the Tax-pCREB complex recruits the cellular co-activator p300 to the promoter through this unconventional Tax-responsive element. We further show that the transducer of regulated CREB 2 (TORC2) cooperates with Tax to further enhance p300 recruitment to the cyclin D1 promoter in vitro. Tax and TORC2 in combination stimulate cyclin D1 expression in vivo, demonstrating the functional outcome of the binding interactions. Together, our findings support a model in which Tax-induced accumulation of cyclin D1 shortens the G1 phase of the cell cycle, promotes mitotic replication of the virus, and drives selection and expansion of malignant T-cells.


Subject(s)
Cyclic AMP Response Element-Binding Protein/metabolism , Cyclin D1/genetics , E1A-Associated p300 Protein/metabolism , Gene Products, tax/metabolism , Human T-lymphotropic virus 1 , Transcription Factors/metabolism , Transcription, Genetic/genetics , Cell Line , Cell Transformation, Viral , Cyclic AMP/genetics , Human T-lymphotropic virus 1/physiology , Humans , NF-kappa B/metabolism , Phosphorylation , Promoter Regions, Genetic/genetics , RNA, Messenger/genetics , RNA, Messenger/metabolism , Response Elements , Signal Transduction , T-Lymphocytes/metabolism , T-Lymphocytes/virology , Transcriptional Activation
11.
Nanotechnology ; 19(42): 424005, 2008 Oct 22.
Article in English | MEDLINE | ID: mdl-21832665

ABSTRACT

The effect of chenodeoxycholic acid as the coadsorbent with a squaraine sensitizer on TiO(2) nanocrystalline solar cells was investigated, and it was found that the coadsorbent prevents the squaraine sensitizer from aggregating on the TiO(2) nanoparticles but reduces dye loading leading to an interdependent photovoltaic performance. Analysis of the absorption spectra, and incident monochromatic photon-to-current conversion efficiency data showed that the load of squaraine sensitizer as well as the appearance of H-aggregates is strongly dependent on the molar concentration of chenodeoxycholic acid coadsorbent. The open circuit voltage of the solar cells with chenodeoxycholic acid increases due to the enhanced electron lifetime in the TiO(2) nanoparticles coupled with the band edge shift of TiO(2) to negative potentials.

12.
Chem Commun (Camb) ; (44): 4680-2, 2007 Nov 28.
Article in English | MEDLINE | ID: mdl-17989831

ABSTRACT

Dye-sensitized solar cells based on co-sensitization of organic dyes having complementary spectral absorption in the visible region resulted in a panchromatic response, which exhibited 86% incident monochromatic photon-to-current conversion efficiency in the visible region; the optimized cell gave a short circuit current density of 15.5 mA cm(-2), an open circuit voltage of 685 mV and a fill factor of 0.70 corresponding to an overall conversion efficiency of 7.43% under solar simulated light irradiation of 100 mW cm(-2).


Subject(s)
Fluorescent Dyes/chemistry , Membranes, Artificial , Nanostructures/chemistry , Titanium/chemistry , Electrodes , Molecular Structure , Sensitivity and Specificity
13.
Cytotherapy ; 9(8): 746-54, 2007.
Article in English | MEDLINE | ID: mdl-17917892

ABSTRACT

BACKGROUND: We sought to develop a method for the clinical large-scale depletion of alphabeta T lymphocytes from mobilized peripheral stem cells, which would allow the allogeneic transplantation of a graft enriched for stem cells, natural killer (NK) cells and gammadelta T lymphocytes. METHODS: Therefore, we obtained mononuclear cells from either mobilized or non-mobilized healthy adult volunteer donors and incubated the cells with a biotinylated anti-alphabeta T-cell Ab and subsequently with an anti-biotin Ab conjugated with magnetic microbeads. The depletion was then performed using a CliniMACS device. RESULTS: The median T-cell depletion was 3.9 log (range 3.5-4.1 log). The recovery of the gammadelta and NK cells was 92% and 80%, respectively. The recovery of CD34+ stem cells from the mobilized donors was 66%. DISCUSSION: This method had no negative influence on the in vitro colony formation of stem cells, and transplantation of alphabeta-depleted cells into NOD-SCID IL-2 common gamma chain knockout (NOD-scid IL2r (null)) mice resulted in a rapid engraftment of human myeloid and lymphoid cells. This method will allow large-scale depletion of alphabeta T cells from mobilized peripheral blood in clinical trials.


Subject(s)
Lymphocyte Depletion/methods , Peripheral Blood Stem Cell Transplantation , Receptors, Antigen, T-Cell, alpha-beta , T-Lymphocytes , Adult , Animals , Hematopoietic Stem Cell Mobilization/methods , Humans , Immunomagnetic Separation/methods , Immunophenotyping , Mice , Mice, Inbred NOD , Mice, SCID , Peripheral Blood Stem Cell Transplantation/methods , Receptors, Antigen, T-Cell, alpha-beta/immunology , T-Lymphocytes/immunology , Transplantation, Homologous
14.
Gene Ther ; 14(24): 1739-49, 2007 Dec.
Article in English | MEDLINE | ID: mdl-17928872

ABSTRACT

Chimeric receptors bearing ligand recognition domains linked to signaling regions from the T-cell receptor can redirect T lymphocytes against non-MHC-restricted targets. Cytolytic T lymphocytes (CTL) expressing these chimeric receptors are being tested in preclinical and clinical trials for activity in cancer, infectious diseases and autoimmunity. The chimeric receptors may incorporate antigenic epitopes previously unrecognized by the immune system. Whether a receptor-specific antibody response develops to these neoantigens and whether such a response inhibits therapeutic cell activity is unknown. We hypothesized that upon engagement of a chimeric receptor-specific B cell, receptor-modified CTL will be activated, lysing the B cell and inducing tolerance to the chimeric receptor rather than immunity. We demonstrate that receptor-modified CTL are indeed stimulated by cognate receptor-specific B cells, proliferate and produce cytokines in response and kill the B cells in vitro and in vivo. However, this is insufficient to induce full B-cell tolerance. Modified CTL induce a chimeric receptor-specific antibody response independent of any other source of antigen. Nevertheless, the CTL retain substantial activity even in the presence of saturating doses of receptor-specific antibody. Thus antichimeric receptor antibody responses need to be considered in the clinical use of chimeric receptor-modified T cells. However, the inhibitory activity of these antibodies may in cases be limited.


Subject(s)
B-Lymphocytes/immunology , Immunotherapy, Adoptive/methods , Neoplasms/therapy , Receptors, Antigen, T-Cell/genetics , T-Lymphocytes, Cytotoxic/immunology , Animals , Antibodies, Monoclonal/immunology , CD28 Antigens/immunology , Cytotoxicity, Immunologic , Genetic Vectors/administration & dosage , Genetic Vectors/genetics , Immune Tolerance , Mice , Mice, Knockout , Mice, Transgenic , Neoplasms/immunology , Receptors, Antigen, T-Cell/immunology , Recombinant Fusion Proteins/administration & dosage , Recombinant Fusion Proteins/genetics , Retroviridae/genetics , Transduction, Genetic/methods
15.
Surg Endosc ; 18(3): 547-51, 2004 Mar.
Article in English | MEDLINE | ID: mdl-15108692

ABSTRACT

BACKGROUND: Paralysis of the diaphragm is a severe complication of cardiothoracic surgery carrying significant morbidity and mortality. This study demonstrates a novel minimally invasive technique for treatment of phrenic nerve injuries presenting with symptomatic eventration of the diaphragm. It also presents long-term results of three patients treated with this operation. METHODS: Chest x-ray proved eventration of the left diaphragm in all patients. Two patients required treatment due to prolonged respirator therapy/assisted ventilation for 4 weeks after cardiac surgery. One patient suffered from progressive dyspnea caused by increasing left-sided diaphragmatic elevation and underwent surgery 2 years after cardiac surgery. In all cases, a minimally invasive abdominal approach was chosen. During surgery the dome of the diaphragm was pulled down via three percutaneously inserted retention stitches. This resulted in two or three folds of the diaphragm located within the abdomen. These diaphragmatic folds were subsequently tightened using 12 to 15 unresorbable sutures with extracorporally prepared knots. Surgical as well as long-term follow-up results are presented of all patients and a review of the current literature is provided. RESULTS: Mean operating time was 203 min; mean intraoperative blood loss was 130 ml. No major complications occurred during surgery or the postoperative period. At a median follow-up of 72 months no recurrence was observed. CONCLUSIONS: Laparoscopic diaphragmatic plication provides excellent relief of symptoms caused by diaphragmatic paralysis. There is no perioperative morbidity, and hospital stay is short. The laparoscopic approach, therefore, is an attractive surgical alternative for the treatment of phrenic nerve palsy and should be considered in all suitable patients.


Subject(s)
Diaphragm/surgery , Intraoperative Complications/surgery , Laparoscopy/methods , Peripheral Nervous System Diseases/surgery , Phrenic Nerve/injuries , Respiratory Paralysis/surgery , Aged , Coronary Artery Bypass , Dyspnea/etiology , Female , Follow-Up Studies , Humans , Middle Aged , Minimally Invasive Surgical Procedures , Peripheral Nervous System Diseases/etiology , Respiration, Artificial , Respiratory Paralysis/etiology , Treatment Outcome
16.
Cytotherapy ; 6(1): 1-6, 2004.
Article in English | MEDLINE | ID: mdl-14985161

ABSTRACT

BACKGROUND: The presence of T and B cells in allogeneic grafts contributes to GvHD and to EBV-associated lymphoproliferative disease (LPD). Depletion of T and B cells from the graft decreases the risk of these complications. METHODS: T and B cells were depleted from mobilized peripheral stem cells from volunteer donors (n=5) using anti-CD3 and anti-CD19 Abs conjugated to magnetic microbeads, and the CliniMACS device. The function of the stem cells after depletion was evaluated using colony assays and non-obese diabetic (NOD)/SCID repopulating experiments. RESULTS: The mean mononuclear cell (MNC) count prior to T- and B-cell depletion was 2.19x10(10) (range 1.48-3.53). After depletion, the mean percentage of contaminating T cells was 0.02% (range 0.01-0.04%) with a mean log(10) depletion of 3.4 (range 3-3.8). The mean percentage of contaminating B cells was 0.1% (range 0.01-0.4%) with a mean log(10) depletion of 2.2 (range 1.4-3). The mean recovery of CD3- and CD19-negative MNCs after depletion was 70% (range 54-88%) and the mean recovery of CD34(+) stem cells was 69% (range 52-98%). The mean number of natural killer (NK) cells after T- and B-cell depletion was 5.2x10(8) (range 2-10x10(8)). In vitro colony assays and in vivo NOD/SCID repopulation assays showed no negative impact of this method on the function of the hematopoietic stem cells. DISCUSSION: Our results show that the CliniMACS system can be used to efficiently deplete PBSC of T and B cells simultaneously, without adverse effect on the graft.


Subject(s)
B-Lymphocytes/immunology , Lymphocyte Depletion/methods , Peripheral Blood Stem Cell Transplantation/methods , T-Lymphocytes/immunology , Animals , Antigens, CD19/analysis , Antigens, CD34/analysis , CD3 Complex/analysis , CD56 Antigen/analysis , Cell Separation/methods , Graft vs Host Disease/prevention & control , Hematopoietic Stem Cell Mobilization , Humans , Killer Cells, Natural/cytology , Mice , Transplantation, Homologous
17.
Leukemia ; 18(4): 676-84, 2004 Apr.
Article in English | MEDLINE | ID: mdl-14961035

ABSTRACT

To develop a therapy for drug-resistant B-lineage acute lymphoblastic leukemia (ALL), we transduced T lymphocytes with anti-CD19 chimeric receptors, consisting of an anti-CD19 single-chain variable domain (reactive with most ALL cases), the hinge and transmembrane domains of CD8alpha, and the signaling domain of CD3zeta. We compared the antileukemic activity mediated by a novel receptor ('anti-CD19-BB-zeta') containing the signaling domain of 4-1BB (CD137; a crucial molecule for T-cell antitumor activity) to that of a receptor lacking costimulatory molecules. Retroviral transduction produced efficient and durable receptor expression in human T cells. Lymphocytes expressing anti-CD19-BB-zeta receptors exerted powerful and specific cytotoxicity against ALL cells, which was superior to that of lymphocytes with receptors lacking 4-1BB. Anti-CD19-BB-zeta lymphocytes were remarkably effective in cocultures with bone marrow mesenchymal cells, and against leukemic cells from patients with drug-resistant ALL: as few as 1% anti-CD19-BB-zeta-transduced T cells eliminated most ALL cells within 5 days. These cells also expanded and produced interleukin-2 in response to ALL cells at much higher rates than those of lymphocytes expressing equivalent receptors lacking 4-1BB. We conclude that anti-CD19 chimeric receptors containing 4-1BB are a powerful new tool for T-cell therapy of B-lineage ALL and other CD19+ B-lymphoid malignancies.


Subject(s)
Burkitt Lymphoma/therapy , Precursor Cell Lymphoblastic Leukemia-Lymphoma/therapy , Receptors, Nerve Growth Factor/therapeutic use , Receptors, Tumor Necrosis Factor/therapeutic use , Recombinant Fusion Proteins/pharmacology , Antigens, CD , Antigens, CD19/immunology , Burkitt Lymphoma/pathology , CD3 Complex/chemistry , CD3 Complex/genetics , CD3 Complex/pharmacology , CD8 Antigens/chemistry , CD8 Antigens/genetics , CD8 Antigens/pharmacology , Cell Line, Tumor , Coculture Techniques , Cytotoxicity Tests, Immunologic , Humans , Immunoconjugates/genetics , Immunoconjugates/pharmacology , Immunoglobulin Variable Region/genetics , Immunoglobulin Variable Region/pharmacology , Immunotherapy , Precursor Cell Lymphoblastic Leukemia-Lymphoma/pathology , Protein Structure, Tertiary , Receptors, Nerve Growth Factor/genetics , Receptors, Tumor Necrosis Factor/genetics , Recombinant Fusion Proteins/genetics , T-Lymphocytes/cytology , T-Lymphocytes/immunology , T-Lymphocytes/metabolism , Transduction, Genetic , Tumor Necrosis Factor Receptor Superfamily, Member 9
18.
Cytotherapy ; 5(6): 479-84, 2003.
Article in English | MEDLINE | ID: mdl-14660043

ABSTRACT

BACKGROUND: Infection, graft failure, disease relapse, and GvHD are significant adverse events associated with allogeneic BMT. Although donor leukocyte infusion has been used to prevent or to treat infection, graft failure, and relapse, the potential clinical benefits are often outweighed by the risk of T cell-mediated GvHD. Results from animal studies suggest that donor natural killer (NK) cells may be an ideal cell type for prevention or treatment of these adverse events. We have therefore sought to develop an automated, efficient, and clinical-scale human NK cell-purification method. METHODS: Twelve leukopheresis products were purified for NK cells using a two-step immunomagnetic method. CD3(+) cells were first depleted from the apheresis products. CD56(+) cells were then enriched from the CD3(+) cell-depleted products. RESULTS: The median percentage of CD3(-)CD56(+) NK cells in the final products was 91.0%, and the median recovery was 48.7%. The median depletion for CD3(+)CD56(-) T cells was 5.3 log. Natural cytotoxicity of the purified cells was approximately five-fold higher than that of unpurified mononuclear cells, and it could be further increased by stimulation of the purified cell with IL2. DISCUSSION: We described a large-scale purification method for automated, efficient, and rapid isolation of human NK cells that yielded minimal contamination with T cells or B cells. These purified NK cells may be expedient for preclinical and clinical uses.


Subject(s)
Immunomagnetic Separation/methods , Killer Cells, Natural/cytology , Antigens, CD19/analysis , CD3 Complex/analysis , CD56 Antigen/analysis , Cell Count , Cell Separation/methods , Cytotoxicity Tests, Immunologic , Flow Cytometry , Humans , Immunomagnetic Separation/instrumentation , Interleukin-12/pharmacology , K562 Cells , Killer Cells, Natural/drug effects , Killer Cells, Natural/immunology , Leukapheresis , Lipopolysaccharide Receptors/analysis
19.
Gene Ther ; 10(7): 594-604, 2003 Apr.
Article in English | MEDLINE | ID: mdl-12646865

ABSTRACT

Chimeric receptors that link ligand recognition domains, such as antibody Fv fragments, with TCR signaling domains can redirect T lymphocytes against MHC-unrestricted targets. Such receptor-modified T lymphocytes have shown promise in the treatment of infectious diseases and cancer. We hypothesized that receptor-modified T lymphocytes may also be designed to target antigen-specific T cells. We synthesized chimeric receptors consisting of the extracellular and transmembrane domains of the class I MHC H-2K(b) molecule linked to the signaling domains of either TCR-zeta, CD28 and zeta, or CD28, zeta, and lck. T lymphocytes modified to express these receptors and pulsed with antigenic peptide specifically killed precursor CTL. Cytolysis was efficient, even at effector:target ratios of less than one, and specific, selectively killing antigen-specific precursor CTL among a mixed population of T cells. Cytolysis required activation of the receptor-modified T cells, and did not occur with a signaling-deficient chimeric receptor. In contrast to precursor CTL, differentiated CTL proved resistant to lysis by the receptor-modified T cells. These data demonstrate the feasibility of redirecting T lymphocytes against antigen-specific T cells. Receptor-modified T cells expressing chimeric MHC receptors have potential application in autoimmune and alloimmune diseases.


Subject(s)
Autoimmune Diseases/therapy , CD8-Positive T-Lymphocytes/immunology , Genetic Therapy/methods , H-2 Antigens/genetics , Receptors, Antigen, T-Cell/genetics , T-Lymphocytes, Cytotoxic/immunology , Animals , CD8 Antigens/genetics , Green Fluorescent Proteins , Immune Tolerance , Luminescent Proteins/genetics , Lymphocyte Activation , Mice , Mice, Transgenic
20.
Bone Marrow Transplant ; 31(1): 17-22, 2003 Jan.
Article in English | MEDLINE | ID: mdl-12621502

ABSTRACT

We have evaluated the feasibility of large-scale isolation of CD133+ progenitors from healthy mobilized adult donors for potential clinical use in autologous and allogeneic transplantation. A total of 11 healthy volunteer adult donors were mobilized with G-CSF. CD133+ stem cells were isolated from a single leukapheresis using the Clinimacs method. The median percentage of CD133 before positive selection was 0.75% (range 0.39-2.03%). After selection, the median purity and recovery was 94% (range 85.2-98.0%) and 69% (range 44-100%), respectively. The median log10 T-cell depletion obtained by CD133+ positive selection was 4.2 (range 3.8-4.7). The CD133+ progenitors were highly enriched in colony-forming units (CFU) and transplantation into NOD/SCID mice resulted in a high engraftment rate. Transplantation of sorted CD133+/CD34+ cells into NOD/SCID mice showed a higher engraftment compared to CD133-/CD34+ cells. Mobilized peripheral CD133+ stem cells can be purified in large scale for potential clinical use. The biological function of the cells is not impaired. The majority of the NOD/SCID repopulating cells are within the CD133+/CD34+ subpopulation. Therefore, clinical studies using purified CD133+ stem cells can be envisoned to further clarify the role of CD133+ stem cells in hematopoietic reconstitution after transplantation.


Subject(s)
Granulocyte Colony-Stimulating Factor/therapeutic use , Hematopoietic Stem Cell Mobilization/methods , AC133 Antigen , Adult , Animals , Antigens, CD/blood , Cell Separation , Colony-Forming Units Assay , DNA Primers , Filgrastim , Flow Cytometry , Glycoproteins/blood , Hematopoietic Stem Cells/cytology , Hematopoietic Stem Cells/immunology , Humans , Leukapheresis , Living Donors , Mice , Mice, Inbred NOD , Mice, SCID , Peptides/blood , Polymerase Chain Reaction/methods , Recombinant Proteins , Transplantation, Heterologous
SELECTION OF CITATIONS
SEARCH DETAIL