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Current research also shows that, like the brain, the Immune System can become senile. These factors play a key role in the pro-to pre-B cell block. It is widely accepted that the ageing process attenuates host ability to mount a robust or effective immune response.

This innate immune response can further progress to an adaptive antigen-specific immune response with the recruitment of effector T and B lymphocytes. Finally, we illuminate potential therapies that could be employed to help us live a longer, fuller and healthier life. Immunosenescence, defined as the changes in the immune system associated with age, has been gathering interest in the scientific and health-care sectors alike. Therefore, it is unsurprising that the increased susceptibility to cancers and infections seen in older persons points to severe deficiencies in the immune system.

This combined circumstance then predisposes the

This latter process is in part mediated by a specialized subset of T cells called regulatory T cells Treg. Together, these data suggest that the composition of bone marrow stroma and its ability to nurture haematopoietic precursors is substantially compromised with ageing. It has recently been demonstrated that thymic atrophy is mediated by a shift from a stimulatory to a suppressive cytokine microenvironment. As with other stromal tissues, the bone marrow itself produces and responds to a wide variety of cytokines and hormones. Although myeloid cell production does not seem to decline with age, macrophages become dysregulated as a consequence of environmental changes.

Jump to navigation Jump to search Immunosenescence refers to the gradual deterioration of the immune system brought on by natural age advancement. There is a notable decline in the total number of phagocytes in aged hosts, coupled with an intrinsic reduction of their bactericidal activity.

This combined circumstance then predisposes the human body to multiple system failure and global demise. Production of broadly reactive T cells by the thymus and maintenance of a diverse peripheral T cell repertoire are critical to the robustness of the human immune system. Only recently have advances in cellular and molecular phenotyping enabled researchers to more clearly elucidate the mechanisms that underlie immunoscenescence associated with ageing.

We conclude with a discussion of the clinical implications of this age-associated decline in immune function, with specific regard to tumour and infectious disease vaccine development. This process is known as Immunosenescence, the condition of decline in immune function as you grow older. Current studies implicate age-induced dysregulation of cytokine and hormone networks with this loss in bone marrow stem cell output across the lifespan.

Chronic involution of the thymus gland is thought to be one of the major contributing factors to loss of immune function with increasing age. We conclude with the clinical implications of age-associated immunosenescence to vaccine development for tumours and infectious disease. It is considered a major contributory factor to the increased frequency of morbidity and mortality among the elderly. The mechanisms that underlie these age-related defects are broad and range from defects in the haematopoietic bone marrow to defects in peripheral lymphocyte migration, maturation and function. The peripheral immune system develops from haematopoietic stem cells that originate in the bone marrow.

Production of broadly reactive T cells

Immunosenescence can also be sometimes envisaged as the result of the continuous challenge of the unavoidable exposure to a variety of antigens such as viruses and bacteria. The expansion of the perivascular space adipocytes, peripheral lymphocytes, stroma with age results in a shift in the ratio of true thymic epithelial space to perivascular space. The rise in its recognition is both pertinent and timely given the increasing average age and the corresponding failure to increase healthy life expectancy.