Search results for "Helper-Inducer"
showing 10 items of 81 documents
Immunological pattern in patients with 21-hydroxylase deficiency.
1994
The aim of this work was to perform an immunological study in six patients with 21 hydroxylase deficiency in mild form (M210HD) and in 2 patients with 21-hydroxylase deficiency in classical form (C210HD) and in their parents, in whom a previous HLA,C4,Bf typing demonstrated high prevalence of DR5 and phenotypic absence of fraction C4B of complement (C4BQO). This study contains the evaluation of C3, IgA, IgG, IgM levels, anticardiolipin antibodies (IgG and IgM) and circulating immunocomplexes. A study of lymphocyte subsets was also performed. Among M210HD 1 patient showed presence of anticardiolipin antibodies both IgM and IgG; this patient had shown antinuclear antibodies in a previous stud…
Tcgfiii/p40 is produced by naive murine cd4+ t cells but is not a general t cell growth factor*
1989
Several antigen-specific T cell lines were found to secrete a lymphokine upon activation by antigen or lectin that was provisionally termed T cell growth factor III (TCGF III) because it induced the proliferation of a CD4+ T cell clone independently from IL2 and IL4. Amino acid sequence analysis (and the functional properties of TCGF III) revealed that TCGF III was identical with a recently identified lymphokine termed P40. TCGF III/P40 was not only produced by long-term cultured T cell lines but also upon stimulation of freshly isolated Mlsa-reactive T cells. In addition, naive CD4+ T cells secreted TCGF III/P40 upon activation by lectin or allo-major histocompatibility complex structures.…
Autocrine transforming growth factor- from chronic lymphocytic leukemia-β cells interferes with proliferative T cell signals
1999
Chronic lymphocytic leukemia (CLL) is characterized by the accumulation of noncycling B cells in lymphatic and extralymphatic tissues. In the present study we investigated the possible contribution of TGF-beta, as secreted by CLL-B cells, on this low proliferative state. CLL-B cells were shown to express TGF-beta RNA and to release bioactive TGF-beta into culture supernatants. Antibody neutralization of endogenously secreted TGF-beta increased the proliferation of CLL-B cells as cultured in the presence of IL-2 or IL-4 or in direct contact with activated CD4+ T cells. In these culture systems, addition of exogenous TGF-beta downregulated basal and cytokineinduced proliferation of CLL-B cell…
Quantitative representation of all T cells committed to develop into cytotoxic effector cells and/or interleukin 2 activity-producing helper cells wi…
1984
A limiting dilution culture system based on stimulation with concanavalin A (Con A) has been used to study the quantitative distribution of helper and of cytotoxic precursor cells in Lyt-2-defined subpopulations of murine T cells. Virtually all of the selected Lyt-2+ and Lyt-2-T cells grow and expand to large clonal colonies within an 8-9-day culture period. Our data show that upon stimulation with Con A, 90% of the Lyt-2-T cells were capable to produce interleukin 2 (IL 2) activity. In addition, IL 2 activity is produced by 8-10% of Lyt-2+ T cells. However, at the clonal level, the average of the IL2 activity produced by Lyt-2+ T cells is about 8-fold less as compared to Lyt-2-T cells. Pre…
Allogeneic effector/memory Th-1 cells impair FoxP3+ regulatory T lymphocytes and synergize with chaperone-rich cell lysate vaccine to treat leukemia
2011
AbstractTherapeutic strategies combining the induction of effective antitumor immunity with the inhibition of the mechanisms of tumor-induced immunosuppression represent a key objective in cancer immunotherapy. Herein we demonstrate that effector/memory CD4+ T helper-1 (Th-1) lymphocytes, in addition to polarizing type-1 antitumor immune responses, impair tumor-induced CD4+CD25+FoxP3+ regulatory T lymphocyte (Treg) immunosuppressive function in vitro and in vivo. Th-1 cells also inhibit the generation of FoxP3+ Tregs from naive CD4+CD25−FoxP3− T cells by an interferon-γ–dependent mechanism. In addition, in an aggressive mouse leukemia model (12B1), Th-1 lymphocytes act synergistically with …
In Vivo Imaging of Partially Reversible Th17 Cell-Induced Neuronal Dysfunction in the Course of Encephalomyelitis
2010
SummaryNeuronal damage in autoimmune neuroinflammation is the correlate for long-term disability in multiple sclerosis (MS) patients. Here, we investigated the role of immune cells in neuronal damage processes in animal models of MS by monitoring experimental autoimmune encephalomyelitis (EAE) by using two-photon microscopy of living anaesthetized mice. In the brainstem, we detected sustained interaction between immune and neuronal cells, particularly during disease peak. Direct interaction of myelin oligodendrocyte glycoprotein (MOG)-specific Th17 and neuronal cells in demyelinating lesions was associated with extensive axonal damage. By combining confocal, electron, and intravital microsc…
Regulation of IgG antibody responses by epitope density and CD21-mediated costimulation
2002
Epitope density and organization have been shown to be important factors for B cell activation in many animal model systems. However, it has been difficult to separate the role of antigen organization from the role of local antigen concentrations because highly organized antigens are usually particulate whereas non-organized antigens are more soluble. Hence, highly organized and non-organized antigens may interact with different cell types and in different locations within lymphoid organs. In order to assess the role of antigen organization in regulating B cell responses, we immunized mice with highly repetitive virus-like particles, which exhibit different epitope densities covalently atta…
In Activated Murine Mast Cells, NFATc2 Is Critical for the Production of Autocrine IL-3, Thereby Promoting the Expression of IL-9
2019
Abstract IL-9 has lent its numerical designation to the Th9 subset of CD4+ Th cells, although it is also produced by additional cell types, including mast cells. It is a pleiotropic cytokine involved in allergic reactions, parasitic infections, autoimmune inflammation, and cancer immunity. In this article, we provide evidence that NFATc2 has contradictory functions in the expression of IL-9 in murine Th9 cells and bone marrow–derived mast cells (BMMC). The basis for this is our observation that the production of IL-9 in NFATc2-deficient Th9 cells is increased, whereas it is decreased in BMMC devoid of NFATc2. In addition, NFATc2 deficiency almost completely abrogates the expression of IL-3 …
Th9 cells, new players in adaptive immunity.
2014
Upon antigen-specific stimulation, naive CD4⁺ T cells have the potential to differentiate into various T helper (Th) cell subsets. Earlier models of Th cell differentiation focused on IFN-γ-producing Th1 cells and IL-4-secreting Th2 cells. The discovery of additional CD4⁺ Th cell subsets has extended our understanding of Th cell differentiation beyond this dichotomy. Among these is the recently described Th9 cell subset, which preferentially produces interleukin (IL)-9. Here, we review the latest developments in Th9 cell development and differentiation, focusing on contributing environmental signals, and discuss potential physiological and pathophysiological functions of these cells. We des…
T helper cell- and CD40-dependent germline IgM prevents chronic virus-induced demyelinating disease
2012
Generation of antiviral IgM is usually considered as a marker of a short-lived initial antibody response that is replaced by hypermutated and more-efficient IgG. However, once viruses have established a particular niche for their persistence (e.g., within the CNS), the immune system has to specifically mobilize a broad range of antimicrobial effectors to contain the pathogen in the long term. Infection of the CNS with the mouse hepatitis virus (MHV) provides a unique model situation in which the extent of inflammatory CNS disease is determined by the balance between antiviral immune control, viral replication, and immune-mediated damage. We show here that whereas antibody- or B cell-defici…