How do I: Evaluate the safety and legitimacy of unproven cellular therapies?

Background: Unproven cellular therapies are being offered to patients for a variety of conditions and diseases for which other treatments have failed. The use of untested cellular therapies is a worldwide problem. Practitioners (e.

Adverse event reporting for cellular therapy products: Current status and future directions.

Adverse event (AE) and adverse reaction (AR) reporting are key components of patient safety and surveillance systems. Review and analysis of this data yields opportunities for process improvement, product information and interventions, and can lead to improved patient outcomes and donor safety overall. AE and AR reporting for cellular therapy products is fragmented and not well characterized in a central reference.

Training practices of cell processing laboratory staff: analysis of a survey by the Alliance for Harmonization of Cellular Therapy Accreditation.

Background Aims: Methods for processing products used for hematopoietic progenitor cell (HPC) transplantation must ensure their safety and efficacy. Personnel training and ongoing competency assessment is critical to this goal. Here we present results from a global survey of methods used by a diverse array of cell processing facilities for the initial training and ongoing competency assessment of key personnel.

Training practices of hematopoietic progenitor cell-apheresis and -cord blood collection staff: analysis of a survey by the Alliance for Harmonisation of Cellular Therapy Accreditation.

Background: As hematopoietic stem cell transplantation expands globally, identification of the key elements that make up high-quality training programs will become more important to optimizing collection practices and quality of the products collected.

Study Design And Methods: Multiple-choice and open questions to identify training practices of those collecting hematopoietic progenitor cell-apheresis [HPC(A)] and -cord blood [HPC(CB)] products were distributed via an electronic survey tool worldwide. Data were collected on facility demographics, job descriptions, and the content of training programs including general practices, staff assessment, retraining, and unique program features.

Combining conventional therapies with intratumoral injection of autologous dendritic cells and activated T cells to treat patients with advanced cancers.

Dendritic cells (DCs) are potent antigen-presenting cells that have been used in cancer immunotherapy. To take advantage of the ability of DCs to acquire antigenic materials from their environment and generate primary as well as recall immune responses, 37 patients with advanced cancers were enrolled in a series of protocols based on direct intratumoral injection of immature DCs. To augment antigen uptake and antitumor immune response, DC injection was combined with radiotherapy or chemotherapy and/or injection of activated T cells.

Functional characterization of ex vivo blood myeloid and plasmacytoid dendritic cells after infection with dengue virus.

Myeloid and plasmacytoid dendritic cells (mDC and pDC) are naturally distinctive subsets. We exposed both subsets to dengue virus (DV) in vitro and investigated their functional characteristics. High levels of DV replication in mDC were found to correlate with DC-SIGN expression.

Multicenter study on in vitro characterization of dendritic cells.

Background: There is growing interest in the use of in vitro-expanded dendritic cells (DC) in cancer immunotherapy as cellular-based vaccines. However, the methods used for in vitro preparation vary widely between institutions. Therefore, a strong need exists for standardization, characterization and quality control (QC) of such vaccines.

CD40 ligand enhances dengue viral infection of dendritic cells: a possible mechanism for T cell-mediated immunopathology.

We have previously shown that dengue virus (DV) productively infects immature human dendritic cells (DCs) through binding to cell surface DC-specific ICAM-3-grabbing nonintegrin molecules. Infected DCs are apoptotic, refractory to TNF-alpha stimulation, inhibited from undergoing maturation, and unable to stimulate T cells. In this study, we show that maturation of infected DCs could be restored by a strong stimulus, CD40L.

Monocyte enrichment of mononuclear apheresis preparations with a multistep back-flush procedure on a cord blood filter.

Introduction: Monocytes or mononuclear cells have been investigated for the treatment of chronic wounds and spinal cord injuries, as well as serve as a source for dendritic or endothelial cell culture. Because these cells may have clinical benefit yet no rapid and inexpensive closed system for monocyte purification is commercially available, a method was investigated to enrich monocytes from mononuclear apheresis units using a cord blood filter.

Methods: A 4-step method for monocyte enrichment was developed which involved 1) filtering a mononuclear apheresis unit through a cord blood filter, 2) chasing with medium to remove non-adherent residual cells and plasma, 3) back-flushing under low shear conditions to remove loosely adherent lymphocytes, and 4) back-flushing under high shear conditions to collect a fraction enriched in monocytes.

Differential effects of dengue virus on infected and bystander dendritic cells.

Dendritic cells (DCs) play a central role as major targets of dengue virus (DV) infections and initiators of antiviral immune responses. Previous observations showed that DCs are activated by infection, presumably acquiring the capacity to promote cell-mediated immunity. However, separate evaluations of the maturation profiles of infected and uninfected bystander cells show that infection impairs the ability of DCs to upregulate cell surface expression of costimulatory, maturation, and major histocompatibility complex molecules, resulting in reduced T-cell stimulatory capacity.

Modulation of dengue virus infection of dendritic cells by Aedes aegypti saliva.

Dengue virus (DV) is a flavivirus carried by the Aedes aegypti mosquito that causes a spectrum of illnesses in the tropics, including dengue fever, dengue hemorrhagic fever, and dengue shock syndrome. Dendritic cells (DCs) are professional antigen presenting cells recently shown to be permissive for DV, and implicated as the primary targets of initial DV infection. DV is transmitted to human host by infected mosquitoes during a blood meal, but it is currently unknown whether transmission is modified by vector saliva that is also deposited in the host's skin during feeding.

Dendritic cell culture: a simple closed culture system using ficoll, monocytes, and a table-top centrifuge.

Dendritic cells (DCs) are potent antigen-presenting cells involved in the induction of T cell-mediated immune responses and as such have emerged as important candidates for cellular-based therapies. Critical to safe clinical use is the easy manipulation of DCs and their precursors in a closed system. We have developed a serum-free, closed culture system applying a simple wash-Ficoll centrifugation method to reduce platelet and red blood cell (RBC) contamination.

A simple cryopreservation method for dendritic cells and cells used in their derivation and functional assessment.

Background: Cryopreservation and storage permitting multiple treatments with single donations is of practical importance to cellular therapies. HES and DMSO, used successfully in simple clinical procedures for freezing marrow and peripheral blood progenitor cells at -80 degrees C, was tested on antigen-presenting dendritic cells (DCs) and cells used in their derivation.

Study Design And Methods: DCs cultured in serum-free media from adherent or CD14+ apheresis MNCs (n = 36) in the presence of GM-CSF + IL4 +/- TNFalpha were frozen and stored at -80 degrees C in 6-percent HES, 5-percent DMSO, and 4-percent HSA.

Regulation of activation-induced receptor activator of NF-kappaB ligand (RANKL) expression in T cells.

Receptor activator of NF-kappaB ligand (RANKL) is a type II membrane protein of the TNF family and plays a critical role in the regulation of osteoclastogenesis. RANKL expressed on osteoblastic stromal cells has been shown to support osteoclast differentiation originated from hematopoietic precursors. Interestingly, RANKL is also expressed on cells of the immune system including T cells and dendritic cells.

Physical interaction between dendritic cells and tumor cells results in an immunogen that induces protective and therapeutic tumor rejection.

Dendritic cells (DCs) are potent professional APCs capable of presenting Ag in the context of costimulatory signals necessary for T cell activation. Although tumor cells express target Ags, they are generally incapable of stimulating an immune response. We show that the short term physical interaction of DCs and tumor cells, with or without cell fusion, results in rapid, efficient, and stable DC-tumor cell association.

Epidermal dendritic cells induce potent antigen-specific CTL-mediated immunity.

Professional antigen-presenting cells (APCs) are required for the initiation of an immune response. Dendritic cells (DCs) are the most potent APCs identified thus far and can present antigen in the context of co-stimulatory signals required for the stimulation of both primed and naïve T cells. Cytotoxic T lymphocytes (CTLs) are critical to the immune response against tumors or virally infected cells.

DNA-based immunization by in vivo transfection of dendritic cells.

Delivery of antigen in a manner that induces effective, antigen-specific immunity is a critical challenge in vaccine design. Optimal antigen presentation is mediated by professional antigen-presenting cells (APCs) capable of taking up, processing and presenting antigen to T cells in the context of costimulatory signals required for T-cell activation. Developing immunization strategies to optimize antigen presentation by dendritic cells, the most potent APCs, is a rational approach to vaccine design.

Peptide-pulsed dendritic cells induce antigen-specific CTL-mediated protective tumor immunity.

Cytotoxic T lymphocytes (CTLs) are a critical component of the immune response to tumors. Tumor-derived peptide antigens targeted by CTLs are being defined for several human tumors and are potential immunogens for the induction of specific antitumor immunity. Dendritic cells (DC) are potent antigen-presenting cells (APCs) capable of priming CTL responses in vivo.

Bone marrow-derived dendritic cells pulsed with synthetic tumour peptides elicit protective and therapeutic antitumour immunity.

Dendritic cells, the most potent 'professional' antigen-presenting cells, hold promise for improving the immunotherapy of cancer. In three different well-characterized tumour models, naive mice injected with bone marrow-derived dendritic cells prepulsed with tumour-associated peptides previously characterized as being recognized by class I major histocompatibility complex-restricted cytotoxic T lymphocytes, developed a specific T-lymphocyte response and were protected against a subsequent lethal tumour challenge. Moreover, in the C3 sarcoma and the 3LL lung carcinoma murine models, treatment of animals bearing established macroscopic tumours (up to 1 cm2 in size) with tumour peptide-pulsed dendritic cells resulted in sustained tumour regression and tumour-free status in more than 80% of cases.

Attenuated immunogenic parasites are essential in the transfer of immunity to virulent Plasmodium berghei.

A less virulent parasite of Plasmodium berghei K173 was isolated that induced immunity against the more virulent parasite. Immunity to this parasite but not to the virulent one, could be transferred by immune spleen cells but not by immune lymph node cells. However, the immune spleen cells did transfer immunity to the virulent strain if accompanied by infection with viable parasites of the less virulent strain, but only if they were allowed to proliferate for a period of 1 week before challenge with the virulent strain.

The need for live parasites for long-term immunity in malaria.

All of the results of the various experiments support a role for living, proliferating parasites in the efficient induction of anti-parasitic as well as anti-disease (CM) immunity. Non-proliferating parasites or material from disrupted parasites are poor or non-antigens in this respect. Three possibilities as to why living parasites are important in immunity could be considered: 1.

Role of the major capsid protein in herpes simplex virus type-1 capsid assembly.

Two herpes simplex virus type 1 (HSV-1) temperature-sensitive (ts) mutants with defects in the gene for the major capsid protein, ICP5, were examined for their effects on virion capsid assembly. Polyacrylamide gel electrophoresis revealed that both mutants were able to synthesize wild-type (WT) levels of ICP5 at the nonpermissive temperature. However, the 53 kD capsid protein disappeared concomitant with the appearance of a new, 51 kD species.

Herpes simplex virus gene products involved in the induction of chromosomal aberrations.

The effect of short-term herpes simplex virus type 1 (HSV-1) infection on chromosomes of human diploid fibroblasts was examined. In addition to chromosomal breaks, gaps and pulverization, three kinds of cytogenetic damage (double minutes, polyploidy and endoreduplication) not yet reported following productive infection with HSV or other animal viruses were frequently observed. Consistent with previous studies suggesting that the expression of immediate-early and/or early viral gene products is required for the induction of chromosomal damage, was the observation that cells infected at the nonpermissive temperature with HSV-1 temperature-sensitive mutants defective in the gene for the immediate-early transcriptional regulatory protein, ICP4, and three early viral gene products--DNA polymerase (pol), the major HSV DNA-binding protein (ICP8) and an HSV-2 mutant defective in alkaline nuclease--exhibited altered patterns of chromosomal damage relative to the effects of wild-type virus on infected cells.