Search results for " immune system"
showing 10 items of 893 documents
Age-related changes in the expression of CD95 (APO1/FAS) on blood lymphocytes☆
1999
Abstract Aging is associated with alterations of the immune system, thought to be related to an increased susceptibility to infectious diseases, and possibly to cancer and autoimmunity in the elderly. In the present paper we report data obtained on freshly collected blood from 148 healthy subjects of different ages (from cord blood to 102 years old). The subjects were divided into seven age classes (cord blood, 3–11 years, 15–39 years, 41–60 years, 61–74 years, 75–84 years, 85–102 years) and their lymphocyte subsets and the expression of the apoptosis-related molecule CD95 were evaluated. In respect of lymphocyte subsets, the major differences were found in the cord-blood samples compared w…
Granulocyte and natural killer activity in the elderly
1999
The deterioration of the immune system in ageing, 'immunosenescence', is thought to contribute to increased morbidity and mortality from infections and possibly autoimmune diseases and cancer. The most profound changes involve effector and immunoregulatory T-cell functions. Immunosenescence appears also to be related to changes in non specific immunity as well. In the present study we have assessed superoxide production, chemotaxis and the expression of the apoptosis-related molecule APO1/Fas (CD95) on neutrophils (PMN) from young and old subjects. Furthermore, we have measured the basal natural killer (NK) activity of young and elderly subjects and we have compared the number of CD16+ cell…
Individual and common antigen-recognition sites of liver-derived T cells in patients with autoimmune hepatitis.
2003
Autoimmune hepatitis (AIH) is characterized by dense T-cell infiltrations in the liver tissue, but little is known how T cells influence the pathogenesis. To address this question, the distribution of T-cell receptor variable beta-chain (TCR Vbeta) transcripts of peripheral blood and liver-infiltrating T cells from previously untreated patients with newly diagnosed acute exacerbated AIH was investigated. Furthermore, the lengths and sequences of complementary-determining region 3 (CDR3) were studied. Reverse transcriptase-polymerase chain reaction (RT-PCR) analysis and CDR3 spectratyping revealed multiple clonal expansions of liver-infiltrating T cells but not peripheral T cells within vari…
Association of T-cell regulatory gene polymorphisms with oral squamous cell carcinoma
2010
Costimulatory molecules have complementary effects on T-cell activation and their balance may control the development of oral cancer. The aim of this study was to determine the relevance of cytotoxic T-lymphocyte antigen 4 (CTLA-4), CD28 and inducible costimulator (ICOS) polymorphisms in oral squamous cell carcinoma (OSCC). Genotyping for CTLA-4 (-1661 A/G and +49 A/G), CD28 (0 C/G and +3160 G/T) and ICOS (+637 A/C and +1599 C/T) was performed in the 83 patients with OSCC, compared to the 40 unrelated healthy volunteers as controls. The genotype CTLA-4 -1661 was significantly different between the patient group and the control group. The allele CTLA-4 -1661 G was significantly found more fr…
Biologic relevance of elevated red cell adenosine deaminase activity in myelodysplastic syndromes and paroxysmal nocturnal hemoglobinuria.
1992
Red cell adenosine deaminase (ADA-RBC) activity in patients with myelodysplastic syndromes and paroxysmal nocturnal hemoglobinuria is significantly increased compared to that observed in normal controls. ADA-RBC activity is not related to fetal hemoglobin concentration, but it is significantly correlated with hemoglobin concentration at diagnosis and with the degree of morphologic dysplasia in the erythroid lineage. The results of our study suggest that the observed enzymatic abnormality may constitute a non-specific manifestation of the stem cell alteration that determines these disorders.
Longitudinal analysis of the T-cell receptor (TCR)-VA and -VB repertoire in CD8+T cells from individuals immunized with recombinant hepatitis B surfa…
2002
SUMMARYRecent studies have suggested that vaccination induces alterations in the T cell receptor (TCR) repertoire. We investigate the diversity of the TCR repertoire after immunization with a recombinant hepatitis B surface vaccine in seven healthy subjects in CD8+ T cells in peripheral blood lymphocytes. Cellular immune responses were monitored over time by sorting CD8 T cells followed by TCR-VA and -VB complementarity determining region 3 (CDR3) analysis. Frequency of individual VB families was determined by flow cytometry. TCR-VA/VB repertoires obtained from CD8+ T cells drawn after vaccination were compared to the TCR repertoire determined prior to vaccination. Monoclonal TCR transcript…
Different KIRs Confer Susceptibility and Protection to Adults with Latent Autoimmune Diabetes in Latvian and Asian Indian Populations
2008
KIRs (killer Ig-like receptors) expressed on natural killer (NK) cells are an important component of innate (and adaptive) immunity. They are either activatory or inhibitory, and certain KIRs are known to interact with specific motifs of HLA Class I molecules, which is very crucial in determining whether a cell is targeted to lysis or otherwise. Latent autoimmune diabetes in adults (LADA) is a slowly progressive form of autoimmune diabetes, with an adult onset (>30 years). Because autoantibodies and autoimmunity involved are involved in the etiology of LADA, KIRs might play an important role in conferring susceptibility to or protection against the disease. The purpose of this study was to …
The Role of Age and Gender in Perceived Vulnerability to Infectious Diseases
2020
Background: The study of the immune system has been approached using two separate paths, the biological immune system and the behavioral immune system. Recently, Gangestad and Grebe proposed a unique integrated compensatory immune system, where both systems work together and one of them could compensate for the other when necessary. However, few studies have confirmed the existence of this integrated compensatory immune system. Our study represents an attempt to explore the existence of this unique immune system, investigating if the behavioral immune system variables increase when the biological immune system weakens with age. Material and Methods. The cross-sectional design study was made…
In vitroresponse toCandida albicansin cultures of whole human blood from young and aged donors
2007
Invasive infections with opportunistic fungi, such as Candida albicans, have become an increasing problem in aged adults in recent years. This work investigates the influence of human ageing on C. albicans recognition by toll-like receptors (TLRs), essential components of the innate immune system, using a cohort of 96 young (15-42 years) and aged (70 years) human volunteers. No significant differences between aged and young donors were observed on (1) cell surface TLR2, TLR6 and TLR4 expression on lymphocytes, monocytes and granulocytes, (2) production of cytokines [IL-8, IL-1beta, IL-6, IL-10, tumour necrosis factor (TNF)-alpha and IL-12p70] and prostaglandin E(2) (PGE(2)) by whole human b…
Over-expression of paneth cell-derived anti-microbial peptides in the gut of patients with ankylosing spondylitis and subclinical intestinal inflamma…
2010
OBJECTIVES: Subclinical gut inflammation has been demonstrated in patients with AS. Altered expression of paneth cell (PC) anti-microbial peptides have been reported in the inflamed ileum of patients with Crohn's disease (CD). Here, we investigated the expression of PC-derived peptides in subclinical gut inflammation in AS. METHODS: Multiple adjacent mucosal biopsies from terminal ileum were obtained from 25 patients with AS, 30 CD and 15 healthy controls (HCs). Expression of human α-defensin 5 (HD-5), phospholipase A2 (PLA2), lysozyme and SOX-9 molecules was assessed by quantitative Taqman RT-PCR on mucosal samples. Immunohistochemistry with anti-human HD-5 antibody and genotyping of relev…