Search results for "TOXICITY"
showing 10 items of 2261 documents
Optimizing Tumor-Reactive γδT Cells for Antibody-Based Cancer Immunotherapy
2010
Monoclonal antibodies (mAbs) constitute the most rapidly growing class of human therapeutics and the second largest class of drugs after vaccines. The treatment of B-cell malignancies and HER2/Neu+ breast cancer has benefited considerably from the use of therapeutic mAbs, either alone or in combination with standard chemotherapy. Frequent relapses, however, demonstrate that the bioactivity of these mAbs is still suboptimal. The concept of improving the anti-tumor activity of mAbs is well established and potentiating the cytotoxicity induced by anticancer mAbs can be achieved by strategies that target the downstream cytolytic effector cells. The recruitment of Fcγ receptor-dependent function…
Targeting a Specific Glycosylated Epitope of CD43 with a New Humanized Monoclonal Antibody for the Treatment of Pediatric and Adult T-Cell Acute Lymp…
2018
Abstract Introduction: T-cell acute lymphoblastic leukemia (T-ALL) accounts for about 20% of pediatric and adult ALL cases. Despite the use of intensive chemotherapy protocols, 25% of children and 50% of adult patients fail to respond or relapse. The 3-years prognosis for these patients is poor and novel treatment options are needed. The targeting of tumor-associated antigens by monoclonal antibodies (mAb) is among the most investigated immune-therapeutic strategies. Accordingly, we developed a new humanized mAb (hUMG1), directed against a heavy glycosylated epitope of CD43 which presents a high reactivity against T-ALL cells. Here we investigated the pre-clinical therapeutic activity and t…
K Cell Activity of Normal and Chronic Lymphocytic Leukaemia Lymphocytes: Association with Lymphocytes bearing Receptors for Human C3b
1977
Surface properties of effector cells in antibody-dependent cell mediated cytotoxicity (ADCC) are at present under intensive investigation. Among these cells a lymphocyte population (K cells) has been described with receptors for the Fc portion of IgG (4), receptors for complement (11) and lacking receptors for sheep red blood cells (SRBC) and surface immunoglobulin (13). The purpose of the present study was to investigate more thoroughly the relationship between K cell activity in ADCC and cells bearing receptors for C3b and C3d.
Synthesis and biological evaluation of (+)-labdadienedial, derivatives and precursors from (+)-sclareolide
2010
Labdadienedial and a series of C15,C16-functionalized derivatives were synthesized from commercial (+)-sclareolide and evaluated for their cytotoxic, antimycotic, and antiviral activities. Their precursors were similarly evaluated.
Synthesis and antimicrobial activity of new 3-(1-R-3(5)-methyl-4-nitroso-1H-5(3)-pyrazolyl)-5-methylisoxazoles.
2000
A number of new 3-(1-R-3(5)-methyl-4-nitroso-1H-5(3)-pyrazolyl)-5-methylisoxazoles 6a-g (7b-f) were synthesized and tested for antibacterial and antifungal activity. Some of these compounds displayed antifungal activity at non-cytotoxic concentrations. Derivative 6c was 9 times more potent in vitro than miconazole and 20 times more selective against C. neoformans. 6c was also 8- and 125-fold more potent than amphotericin B and fluconazole, respectively. None of the compounds was active against bacteria. Preliminary structure-activity relationship (SAR) studies showed that the NO group at position 4 of the pyrazole ring is essential for the activity. Lipophilicity of the pyrazole moiety, N-a…
Nephrotoxicity in the setting of invasive fungal diseases
2008
Amphotericin B, a broad spectrum antifungal agent, is widely used despite significant adverse events including nephrotoxicity. Nephrotoxicity occurs frequently in patients receiving amphotericin B. Different definitions for nephrotoxicity are reviewed in the context of outcome in patients with invasive fungal diseases. In most publications, mortality was higher in patients experiencing nephrotoxicity and mean hospital length of stay was prolonged. As a consequence, the use of less nephrotoxic antifungal agents could improve treatment outcomes.
Postnatal development of functional T cell subsets in the mouse: a frequency analysis of mitogen reactive precursors of proliferating, of cytotoxic a…
1985
In order to study the postnatal development of functional T cell subsets in the mouse, a mitogen-driven limiting dilution culture system was used for a precursor frequency analysis of proliferating, of cytolytic and of IL 2-producing T cells, respectively, present in spleen and thymus of mice from neonatal to adult age. In adult mice, the majority (up to 100%) of splenic T cells was capable to respond to Concanavalin A. In contrast, an up to tenfold lower frequency of mitogen-reactive precursors was found within positively selected Thy-1+ spleen cells of neonatal mice. Within this fraction of Con A reactive neonatal T cells, there was an apparent imbalance in the CTLp/PTLp ratio within the …
Identification of epitopes of Mycobacterium tuberculosis 16-kDa protein recognized by human leukocyte antigen-A*0201 CD8(+) T lymphocytes.
2002
CD8(+) T cells could make an important contribution to protection against tuberculosis (TB), but the antigenic determinants recognized in the context of major histocompatibility complex class I molecules remain ill defined. Our aim was to identify nonamer peptides derived from the acr/16-kDa antigen. Two immunogenic peptides (p21-29 and p120-128) were identified by their ability to elicit cytotoxic CD8(+) T cells from juvenile patients recovering from TB. Epitope-specific recognition was demonstrated by the lysis of both Mycobacterium tuberculosis-infected and peptide-pulsed macrophages, the release of cytotoxic granules, and interferon-gamma and tumor necrosis factor-alpha production. CD8(…
Clonal analysis of human T cell activation by the Mycoplasma arthritidis mitogen (MAS)
1988
Mycoplasma arthritidis produces an as yet undefined soluble molecule (MAS) that has a potent mitogenic effect on T cells of several species. We have used cloned human cytotoxic and proliferative T lymphocytes to dissect the molecular mechanism of T cell activation by this mitogen. Reactivity to MAS is clonally expressed among T cell receptor (TcR) alpha/beta chain-expressing T cell clones of CD4+ or CD8+ phenotype, as well as CD4-8- TcR alpha/beta chain-negative T lymphocyte clones expressing the CD3-associated TcR gamma chain. MAS is able to induce cytotoxicity and/or proliferation in these T cell clones. For triggering of these T cells, regardless of their phenotype of specificity, the pr…
Granulysin‐Dependent Killing of Intracellular and ExtracellularMycobacterium tuberculosisby Vγ9/Vδ2 T Lymphocytes
2001
Contribution of Vgamma9/Vdelta2 T lymphocytes to immune protection against Mycobacterium tuberculosis is still a matter of debate. It was reported earlier that Vgamma9/Vdelta2 T lymphocytes kill macrophages harboring live M. tuberculosis through a granule-dependent mechanism that results in killing of intracellular bacilli. This study found that Vgamma9/Vdelta2 T lymphocytes reduce the viability of both extracellular and intracellular M. tuberculosis. Granulysin and perforin, both detected in Vgamma9/Vdelta2 T lymphocytes, play a major role, which indicates that Vgamma9/Vdelta2 T lymphocytes directly contribute to a protective host response against M. tuberculosis infection.