Search results for "Immune system"

Immune-inflammatory markers and arterial stiffness indexes in subjects with acute ischemic stroke.

2010

Abstract No study has yet evaluated the relationship between arterial stiffness indexes and immuno-inflammatory pathway in patients with an acute cardiovascular or cerebrovascular event. The aim of our study was to evaluate in patients with acute ischemic stroke the relationship between immune-inflammatory markers and arterial stiffness indexes. Methods 107 subjects with acute ischemic stroke and 107 controls without stroke. We evaluated plasma levels of C-reactive protein (CRP), interleukin-1beta (IL-1β), tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) and interleukin-10 (IL-10), E-selectin, P-selectin, intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1…

Programmed death-1 (PD-1): A novel mechanism for understanding the acute immune deregulation in ST-segment elevation myocardial infarction

2014

A study of serum immunoglobulin levels in elderly persons that provides new insights into B cell immunosenescence.

2007

The literature on immunosenescence has focused mainly on T cell impairment. With the aim of gaining insight into B cell immunosenescence, we investigated the serum immunoglobulin levels in a cohort of 166 subjects (20-106 years). Serum IgG (and IgG subclasses) were quantified by the nephelometric technique, IgE by CAP system fluorescence enzyme immunoassay, and IgD by radial immunodiffusion (RID). There was an age-related increase of IgG and IgA; the IgG age-related increase was significant only in men, but IgG1 levels showed an age-related increase both in men and women, whereas IgG3 showed an age-related increase only in men. IgE levels remain unchanged, whereas IgD and IgM serum levels d…

Adaptive immune responses to SARS-CoV-2 in recovered severe COVID-19 patients

2021

ABSTRACTObjectivesThere is an imperative need to determine the durability of adaptive immunity to SARS-CoV-2. We enumerated SARS-CoV-2-reactive CD4+ and CD8+ T cells targeting S1 and M proteins and measured RBD-specific serum IgG over a period of 2-6 months after symptoms onset in a cohort of subjects who had recovered from severe clinical forms of COVID-19.MethodsWe recruited 58 patients (38 males and 20 females; median age, 62.5 years), who had been hospitalized with bilateral pneumonia, 60% with one or more comorbidities. IgG antibodies binding to SARS-CoV-2 RBD were measured by ELISA. SARS-CoV-2-reactive CD69+-expressing-IFNγ-producing-CD4+ and CD8+ T cells were enumerated in heparinize…

Leukocyte Rheology Before and After Chemotactic Activation in some Venous Diseases

1999

Abstract Objective: to evaluate leukocyte rheology, polymorphonuclear leukocyte (PMN) membrane fluidity and cytosolic Ca2+ concentration in subjects with post-phlebitic leg syndrome (PPS) and acute deep-venous leg thrombosis (DVT). Subjects: twenty-two subjects with leg PPS and 14 subjects with leg DVT. Methods: we evaluated the leukocyte filtration (unfractionated, mononuclear cells (MN) and PMN), the PMN membrane fluidity and the PMN cytosolic Ca2+ concentration. Subsequently, we evaluated the same PMN variables after in vitro chemotactic activation with 4-phorbol 12-myristate 13-acetate (PMA) and N -formyl-methionyl-leucyl-phenylalanine (fMLP). Results: at baseline we observed a signific…

Inflammation in right ventricular dysfunction due to thromboembolic pulmonary hypertension

2009

Activation of the immune system is well established in patients with chronic heart failure (CHF) and impaired left ventricular function. High levels of pro-inflammatory cytokines are associated with a poor prognosis. Chronic thromboembolic pulmonary hypertension (CTEPH) frequently leads to impaired right ventricular function. It is not known whether such patients display chronic immune activation as well.We studied 49 patients with CTEPH (50±2 years, right ventricular ejection fraction [RVEF] 29±2%, left ventricular ejection fraction [LVEF] 51±3%, mean±SEM) and compared their results with 17 patients with CHF (71±2 years, LVEF 23±1%) and 34 age-matched control subjects (age 57±2 years). We …

Langerin+ DCs regulate innate IL-17 production in the oral mucosa during Candida albicans-mediated infection

2018

The opportunistic fungal pathogen Candida albicans frequently causes diseases such as oropharyngeal candidiasis (OPC) in immunocompromised individuals. Although it is well appreciated that the cytokine IL-17 is crucial for protective immunity against OPC, the cellular source and the regulation of this cytokine during infection are still a matter of debate. Here, we directly visualized IL-17 production in the tongue of experimentally infected mice, thereby demonstrating that this key cytokine is expressed by three complementary subsets of CD90+ leukocytes: RAG-dependent αβ and γδ T cells, as well as RAG-independent ILCs. To determine the regulation of IL-17 production at the onset of OPC, we…

COVID-19 in people living with HIV: Clinical implications of dynamics of the immune response to SARS-CoV-2.

2020

ABSTRACT Background Little evidence on COVID‐19 in people living with HIV (PLWH) is currently available. Material and Methods We reported clinical and viro‐immunological data of all HIV‐positive patients admitted to our centre with COVID‐19 from March 1 to May 12,2020. Results Overall, five patients were included: all were virologically‐suppressed on antiretroviral therapy and CD4+ count was >350 cell/mm3 in all but two patients. Although all patients had evidence of pneumonia on admission, only one developed respiratory failure. SARS‐CoV‐2‐RNA was never detected from nasopharyngeal swabs in two patients, whereas, in the others, viral clearance occurred within a maximum of 43 days. IgG prod…

A non-redundant role for OX40 in the competitive fitness of Treg in response to IL-2.

2010

OX40 stimulation is known to enhance activation of effector T cells and to inhibit induction and suppressive function of Treg. Here we uncovered a novel role of OX40 in sustaining Treg competitive fitness in vivo, during repopulation of lymphopenic hosts and reconstitution of BM chimeras. Defective expansion of OX40-null Treg diminished their ability to suppress inflammation in a model of lymphopenia-driven colitis. OX40-mediated promotion of Treg fitness spanned beyond lymphopenic environments, as endogenous Treg in OX40-null mice showed decreased accumulation during thymic development, enhanced susceptibility to antibody-mediated depletion and defective turnover following thymectomy. In v…

Reconstitution of the Complement Function in C1q-Deficient (C1qa−/−) Mice with Wild-Type Bone Marrow Cells

2001

Abstract Besides Ab-independent and Ab-dependent activation of the complement classical pathway in host defense, C1q plays a key role in the processing of immune complexes and in the clearance of apoptotic cells. In humans, C1q deficiency leads to systemic lupus erythematosus-like symptoms in over 90% of the cases, thus making this defect a strong disease susceptibility factor. Similarly, C1q-deficient mice (C1qa−/−) develop systemic lupus erythematosus-like symptoms, such as autoantibodies and glomerulonephritis. We have previously provided evidence that C1q is produced by cells of the monocyte-macrophage lineage. In this study, we have tested whether transplantation of bone marrow cells w…