Ageing in immune reactivity is described at the level of lymphoid cells, at that of lymphoid organs and organ function, and at that of regulation of cell and organ function. Apart from shifts in numbers of lymphoid cell subpopulations, the decrease in communication capacity between lymphoid cell populations and in binding of invaders (like bacteria) is an important aspect of ageing. These aspects may contribute to the decreased immune reactivity to invaders and the enhanced incidence of immune reactions to self-components (autoimmune reactivity).
Lymphocytes have a finite and predictable proliferative life span in culture similar to that observed in fibroblasts. In general, the senescence of human fibroblasts is inevitable and irreversible, but their proliferative life span can be extended by certain DNA tumor virus oncogenes, such as the large T antigen of the SV40 virus. Here, we show that human T lymphocytes (HTL) can be stably transfected with SV40 large T and that expression of T antigen extended the life span of T cell cultures.
Carnosine (beta-alanyl-L-histidine), an abundant naturally-occurring dipeptide has been shown to exhibit anti-ageing properties towards cultured cells, possibly due in part to its antioxidant/free radical scavenging abilities. In this paper the results of an investigation on the effects of carnosine, at the physiological concentration of 20 mM, on oxidative DNA damage levels and in vitro lifespan in peripheral blood derived human CD4+ T cell clones are reported.
Helminth parasites survive through a combination of parasite longevity, repeated re-infection and selective immune suppression to prevent protective Th2 responses. To counteract helminth-induced immunosuppression, and to induce long-term immunological memory, understanding of the multiple regulatory pathways within the T cell compartment is needed. Extrinsic inhibition by regulatory T cells is a key element of Th2 suppression.
Throughout life, there is an aging of the immune system that causes impairment of its defense capability. Prevention or delay of this deterioration is considered crucial to maintain general health and increase longevity. We evaluated whether dietary supplementation with Lactobacillus delbrueckii subsp. bulgaricus 8481 could enhance the immune response in the elderly. This multi-center, double-blind, and placebo controlled study enrolled 61 elderly volunteers who were randomly assigned to receive either placebo or probiotics. Each capsule of probiotics contained at least 3?◊?10(7)? L.
We studied the basic indicators of immune status of healthy persons of different age groups living in the monsoon climate in the southern Far East. The analysis shows age-dependent development of immunodepressive status, combined with increasing levels of CD16, CD25 and HLA-DR in the aging organism. Climatic and anthropogenic factors effect profoundly damaging on the body, which results in the severity of disorders of the immune system in old, old age and longevity.
Discoveries of immunomodulatory functions in mesenchymal stem cells (MSCs) have suggested that they might have therapeutic utility in treating immune diseases. Recently, a novel MSC population was identified from dental pulp of human supernumerary teeth, and its multipotency characterized. Herein, we first examined the in vitro and in vivo immunomodulatory functions of human supernumerary tooth-derived stem cells (SNTSCs).
It is well accepted that Ag-induced B cell differentiation often results in the generation of exceptionally long-lived plasma cells. Much of the work supporting this viewpoint stems from studies focused on germinal center-derived plasma cells secreting high-affinity isotype-switched Abs in mice immunized with T cell-dependent Ags. In contrast, less attention has been devoted to understanding Ab responses to T cell-independent Ags and pathogens.
The Journals of Gerontology. Series A, Biological Sciences and Medical Sciences
People may reach the upper limits of the human life span at least partly because they have maintained more appropriate immune function, avoiding changes to immunity termed "immunosenescence." Exceptionally long-lived people may be enriched for genes that contribute to their longevity, some of which may bear on immune function. Centenarian offspring would be expected to inherit some of these, which might be reflected in their resistance to immunosenescence, and contribute to their potential longevity.
The decrease of TCR diversity with aging has never been studied by direct methods. In this study, we combined high-throughput Illumina sequencing with unique cDNA molecular identifier technology to achieve deep and precisely normalized profiling of TCR ? repertoires in 39 healthy donors aged 6-90 y. We demonstrate that TCR ? diversity per 10(6) T cells decreases roughly linearly with age, with significant reduction already apparent by age 40. The percentage of naive T cells showed a strong correlation with measured TCR diversity and decreased linearly up to age 70.