Search results for "Activation"
showing 10 items of 2079 documents
Hepatitis B surface antigen presentation and HLA-DRB1*– lessons from twins and peptide binding studies
2005
Summary The aim of this study was to investigate the underlying mechanisms of the genetic association between certain HLA-DRB1* alleles and the immune response to HBsAg vaccination. Therefore, HBsAg peptide binding to HLA-DR molecules was measured in vitro by peptide binding ELISAs. Additionally, HBsAg-specific T cell reaction and cytokine profile of immune response were analysed ex vivo in ELISPOT assays and DR-restriction of T-cell proliferative responses was investigated with HBsAg specific T cell clones. In addition, we compared HBsAg specific T cell responses of 24 monozygotic and 3 dizygotic twin pairs after HBsAg vaccination. Our results showed that the peptide binding assays did not…
Effect of cordycepin on interleukin-10 production of human peripheral blood mononuclear cells
2002
Therapeutic options for controlling autoimmune diseases are still very limited. Interleukin-10 has been reported to be a promising approach to therapeutic intervention. In the search for a drug which results in the selective upregulation of interleukin-10, we investigated the immunoregulative effects of cordycepin. We have measured interleukin-10 and interleukin-2 secretion of human peripheral blood mononuclear cells that were incubated with cordycepin and assessed the influence of cordycepin on the expression of interleukin-10 mRNA, the proliferative response and the expression of surface markers on T lymphocytes. In addition, the subsets of interleukin-10-secreting cells, the influence of…
Genome-based in silico identification of new Mycobacterium tuberculosis antigens activating polyfunctional CD8+ T cells in human tuberculosis.
2011
Although CD8(+) T cells help control Mycobacterium tuberculosis infection, their M. tuberculosis Ag repertoire, in vivo frequency, and functionality in human tuberculosis (TB) remains largely undefined. We have performed genome-based bioinformatics searches to identify new M. tuberculosis epitopes presented by major HLA class I supertypes A2, A3, and B7 (covering 80% of the human population). A total of 432 M. tuberculosis peptides predicted to bind to HLA-A*0201, HLA-A*0301, and HLA-B*0702 (representing the above supertypes) were synthesized and HLA-binding affinities determined. Peptide-specific CD8(+) T cell proliferation assays (CFSE dilution) in 41 M. tuberculosis-responsive donors ide…
Gamma/delta T lymphocytes are affected in the elderly
2002
gammadelta T lymphocytes are considered to represent a link between the inflammatory response and adaptive immunity. In the present paper we investigated whether these cells play any role in the remodeling of the immune system described in the elderly. We show that the absolute number of gammadelta T cells in peripheral blood of old and very old subjects is reduced. Moreover, gammadelta T cells from old people and centenarians show enhanced levels of the early activation marker CD69 both after culture in medium alone and in LPS-stimulated cells. Furthermore, they show a basal increased production of tumor necrosis factor (TNF)-alpha as evaluated at the single cell level. Additionally, the r…
Enzymatic modification of low-density lipoprotein in the arterial wall: a new role for plasmin and matrix metalloproteinases in atherogenesis.
2004
Objective— Functionally interactive proteases of the plasminogen/plasmin and the matrix metalloproteinase (MMP) system degrade and reorganize the extracellular matrix of the vessel wall in atherosclerosis. Here we investigated whether such proteases are able to confer atherogenic properties onto low density lipoprotein by nonoxidative modification. Methods and Results— Similar to the recently described enzymatically-modified low-density lipoprotein (E-LDL), native LDL exposed to plasmin or matrix MMP-2 or MMP-9 and cholesterylester-hydrolase (CEH) showed extensive deesterification, with ratios of free cholesterol to total cholesterol rising to 0.8 compared with 0.2 in native LDL. When the …
HBV reactivation in patients with HCV/HBV cirrhosis on treatment with direct-acting antivirals
2017
Anecdotal reports suggest that patients with chronic hepatitis C virus (HCV) hepatitis and overt or occult hepatitis B virus (HBV) coinfection may reactivate HBV when HCV is suppressed or cleared by direct-acting antivirals (DAAs). We assessed the prevalence of overt or previous HBV coinfection and the risk of HBV reactivation in patients with HCV cirrhosis treated with DAAs. This was a retrospective cohort of 104 consecutive patients with HCV cirrhosis treated with DAAs. Serum HCV-RNA and HBV-DNA were tested at weeks 4, 8 and 12 of DAAs therapy and at week 12 of follow-up. At the start of DAAs, eight patients (7.7%) were HBsAg positive/HBeAg negative with undetectable HBV-DNA and low level…
The burden of HBV infection in HCV patients in Italy and the risk of reactivation under DAA therapy
2019
Background: There is increasing awareness of HBV reactivation in HCV-RNA-positive/HBV-coinfected patients with chronic liver disease (CLD) treated with oral direct-acting antivirals (DAAs). Aim: To provide figures on the prevalence of HBV markers in HCV-RNA-positive subjects in Italy, where these findings are lacking. Methods: All subjects aged ≥18 years with CLD consecutively referring to Italian liver units located throughout country were prospectively enrolled in two national surveys in 2001 and 2014. Results: The total number of HCV-RNA-positive cases was 6984; 356 (5.1%) subjects vaccinated against HBV were excluded. A total of 6628 cases were evaluated. The prevalence rates of HBsAg, …
Disparities in the prevalence of clinical features between systemic juvenile idiopathic arthritis and adult-onset Still's disease
2022
Abstract Objective To compare clinical features and treatments of patients with systemic JIA (sIJA) and adult-onset Still’s disease (AOSD). Methods The clinical charts of consecutive patients with sJIA by International League of Association of Rheumatology criteria or AOSD by Yamaguchi criteria were reviewed. Patients were seen at a large paediatric rheumatology referral centre or at 10 adult rheumatology academic centres. Data collected included clinical manifestations, inflammation biomarkers, systemic score, macrophage activation syndrome (MAS), parenchymal lung disease, disease course, disability, death and medications administered. Results A total of 166 patients (median age at diagnos…
Correlation of Clinical and Immunologic Parameters of the Inflammatory Activity of Pulmonary Sarcoidosis
1991
The evaluation of activation markers such as T4/T8 ratio and HLA-DR expression of lymphocytes of bronchoalveolar lavage (L-BAL) is an important clinical approach for the staging of sarcoidosis. However, it is not known to what extent this is paralleled by an exaggerated lymphocyte function. We investigated the dependence of L-BAL activation markers on the production of interleukin-2 (IL-2) by L-BAL and on the soluble IL-2 receptor serum level (sIL-2R) in 116 patients with sarcoidosis. In none of the combinations tested was a correlation between the two groups of parameters found; r less than 0.5, upper 90% confidence limit of r less than 0.8. Interestingly, IL-2 production is independent of…
Spontaneous Monokine Release by Alveolar Macrophages in Chronic Sarcoidosis
1991
In pulmonary sarcoidosis an activation of alveolar T lymphocytes and alveolar macrophages (AM) has been demonstrated. There is evidence that in contrast to acute disease a heightened T-cell response cannot be observed in the chronic phase of sarcoidosis. The role of AM in the inflammatory process of chronic sarcoidosis is not yet intensively evaluated. To address this question we measured the release of tumor necrosis factor alpha (TNFα) and interleukin-1 (IL-1) by AM of 39 patients with chronic sarcoidosis (duration > 4 years; 30 active, 9 inactive diseases) without therapy and correlated the monokine release with parameters of T-cell alveolitis and the course of the disease. The T4/T8 …