Search results for "humoral"
showing 10 items of 78 documents
Modulation of immune responses of Rhynchophorus ferrugineus (Insecta: Coleoptera) induced by the entomopathogenic nematode Steinernema carpocapsae (N…
2014
Aim of this study was to investigate relationships between the red palm weevil (RPW) Rhynchophorus ferrugineus (Olivier) and the entomopathogenic nematode Steinernema carpocapsae (EPN); particularly, the work was focused on the immune response of the insect host in naive larvae and after infection with the EPN. Two main immunological processes have been addressed: the activity and modulation of host prophenoloxidase-phenoloxidase (proPO) system, involved in melanization of not-self and hemocytes recognition processes responsible for not-self encapsulation. Moreover, immune depressive and immune evasive strategies of the parasite have been investigated. Our results suggest that RPW possess a…
Suppression of humoral antibody formation against sheep red blood cells by infections with HSV-2 and the influence of mouse cytomegalovirus
1987
HSV-2 infections suppress the antibody response to HSV-1 but do not impair the mouse cytomegalo virus (MCMV) antibody generating system. In contrast, the sheep red blood cell (SRBC) IgM response is impaired by preinfections with HSV-2 but not with HSV-1. From the time kinetics of this suppression it can be concluded that only a certain submechanism "spills over" to the SRBC system. MCMV suppresses the antibody formation induced by HSV-1.
Disrupting immune regulation incurs transient costs in male reproductive function.
2014
9 pages; International audience; BACKGROUND: Immune protection against pathogenic organisms has been shown to incur costs. Previous studies investigating the cost of immunity have mostly focused on the metabolic requirements of immune maintenance and activation. In addition to these metabolic costs, the immune system can induce damage to the host if the immune response is mis-targeted or over-expressed. Given its non-specific nature, an over-expressed inflammatory response is often associated with substantial damage for the host. Here, we investigated the cost of an over-expressed inflammatory response in the reproductive function of male mice. METHODOLOGY/PRINCIPAL FINDINGS: We experimenta…
Hepatitis C virus antibody secretion in vitro by peripheral blood lymphocytes.
1992
A recombinant polypeptide corresponding to a virus-specific cDNA clone (c100-3) serves as the antigen for a hepatitis C virus (HCV) antibody assay. Previous investigations have shown an 80% prevalence of HCV antibodies in sera of patients suffering from post-transfusional chronic hepatitis non-A, non-B, but positive results were also obtained for 30 to 70% of sera from patients with chronic hepatitis B or autoimmune hepatitis. In this study we show that HCV antibodies are secreted by peripheral blood lymphocytes (PBL) in vitro. PBL from 12/35 patients with chronic non-A, non-B hepatitis and 1/6 patients with chronic active hepatitis B spontaneously secreted HCV antibodies in cell culture su…
Humoral Mechanisms in T cell Vaccination: Induction and Functional Characterization of Anti-lymphocytic Autoantibodies
1997
T cell vaccination, the application of syngeneic attenuated T cells, has been shown to prevent effectively and treat experimental autoimmune diseases, but its mechanisms of action are poorly understood. Here we present data on the induction of a humoral anti-T cell response by T cell vaccination, capable of strongly inhibiting T cell proliferation and of ameliorating experimental autoimmune disease. T cell vaccination in the Lewis rat induced autoantibodies reactive with several syngeneic T cell proteins. These autoantibodies were not detectable in normal Lewis sera as assessed by immunoblotting and flow cytometry with intact syngeneic T cells. The autoantibody reactivity was not restricted…
Immunodefense in Tunicates: Cells and Molecules
2001
There are several reasons for analyzing tunicate immune systems. First, they can be established as primitive models for understanding fundamental immunological mechanisms by analyzing their individual cells and molecular products either in vivo or in vitro. Discovered mechanisms could provide alternatives to traditional (vertebrate) mammalian (mouse, rat) and emerging models (fish, amphibian reptile) in answering basic questions concerning immunity and disease in protochordates, the ancestors of vertebrates. Second in vitro, biochemical, immunochemical, and serological analyses coupled with molecular approaches are useful as we search for common molecules (e.g. markers of lymphocyte-like ce…
The T-cell response in patients with cancer
2002
Publisher Summary The chapter examines several methods to measure human T-cell responses, including ELISPOT analysis, intracellular cytokine staining of immune cells after antigenic stimulation, limiting dilution analysis, conventional cloning, and molecular definition of the T-cell response either in the peripheral circulation or in situ in patients with cancer The chapter presents the cellular immune response in patients with cancer. The chapter explores the recent studies that suggest humoral immunity and T-cell-mediated immunity are closely linked. In addition, most of the data concerning antitumor immune responses have been generated using MHC class I tetramer reagents. The ultimate go…
Mast cells enhance proliferation of B lymphocytes and drive their differentiation toward IgA-secreting plasma cells.
2010
AbstractThe evidence of a tight spatial interaction between mast cells (MCs) and B lymphocytes in secondary lymphoid organs, along with the data regarding the abundance of MCs in several B-cell lymphoproliferative disorders prompted us to investigate whether MCs could affect the proliferation and differentiation of B cells. To this aim, we performed coculture assays using mouse splenic B cells and bone marrow–derived MCs. Both nonsensitized and activated MCs proved able to induce a significant inhibition of cell death and an increase in proliferation of naive B cells. Such proliferation was further enhanced in activated B cells. This effect relied on cell-cell contact and MC-derived interle…
Mechanisms underlying lineage commitment and plasticity of human γδ T cells.
2012
Phenotypic and functional heterogeneity are the hallmarks of effector and memory T cells. Upon antigen stimulation, γδ T cells differentiate into two major types of memory T cells: central memory cells, which patrol the blood and secondary lymphoid organs, and effector memory cells, which migrate to peripheral tissues. γδ T cells display in vitro a certain degree of plasticity in their function that is reminiscent of that which is observed in conventional CD4 T cells. Similar to CD4 T cells, in which a plethora of specialized subsets affect the host response, γδ T cells may readily and rapidly assume distinct Th1-, Th2-, Th17-, T(FH) and T regulatory-like effector functions, suggesting that…
Characterizing the Invasive Tumor Front of Aggressive Uterine Adenocarcinoma and Leiomyosarcoma
2021
The invasive tumor front (the tumor–host interface) is vitally important in malignant cell progression and metastasis. Tumor cell interactions with resident and infiltrating host cells and with the surrounding extracellular matrix and secreted factors ultimately determine the fate of the tumor. Herein we focus on the invasive tumor front, making an in-depth characterization of reticular fiber scaffolding, infiltrating immune cells, gene expression, and epigenetic profiles of classified aggressive primary uterine adenocarcinomas (24 patients) and leiomyosarcomas (11 patients). Sections of formalin-fixed samples before and after microdissection were scanned and studied. Reticular fiber archit…