Immunosenescence of macrophages: reduced MHC class II gene expression

Herrero, Carmen; Sebastián, Carlos; Marqués, Laura; Comalada, Mònica; Xaus, Jordi; Valledor, Annabel F.; Lloberas, Jorge; Celada, Antonio

doi:10.1016/s0531-5565(01)00205-4

Cited by 103 publications

(55 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These data indicate that proinflammatory cytokine responses decline with aging when TLR2, 3, 4, 5, and 9 on splenic or thioglycollate-elicited macrophages are stimulated with their ligands. TNF-␣ enhances class I and class II MHC expression and decreased levels in aging could affect Ag processing and presentation, thus affecting T cell responses (22). Reduced TNF-␣ levels in aging may also contribute to reduced phagocytic activity, reduced NO, reduced tumor cell killing, and delayed tissue repair process.…”

Section: Resultsmentioning

confidence: 99%

Cutting Edge: Impaired Toll-Like Receptor Expression and Function in Aging

Renshaw

Rockwell

Engleman

et al. 2002

The Journal of Immunology

550

372

View full text Add to dashboard Cite

Toll-like receptors (TLR) are pattern recognition receptors that recognize conserved molecular patterns on microbes and link innate and adaptive immune systems. We investigated whether the enhanced susceptibility to bacterial, yeast, and viral infections and poor adaptive immune responses in aging are a result of diminished expression and function of TLRs. We examined the expression and function of all murine TLRs on macrophages from young and aged mice. Both splenic and activated peritoneal macrophages from aged mice expressed significantly lower levels of all TLRs. Furthermore, macrophages from aged mice secreted significantly lower levels of IL-6 and TNF-α when stimulated with known ligands for TLR1 and 2, 2 and 6,TLR3, TLR4, TLR5, and TLR9 when compared with those from young mice. These results support the concept that increased susceptibility to infections and poor adaptive immune responses in aging may be due to the decline in TLR expression and function.

show abstract

Section: Resultsmentioning

confidence: 99%

Cutting Edge: Impaired Toll-Like Receptor Expression and Function in Aging

Renshaw

Rockwell

Engleman

et al. 2002

The Journal of Immunology

550

372

View full text Add to dashboard Cite

show abstract

“…Macrophages/monocytes. Even though the number and phagocytic activity of macrophages is unchanged with age, impaired antigen presentation and reduced MHC II molecule expression have been demonstrated in macrophages from aged mice (47). However, after activation by mitogen, peripheral blood mononuclear cells from older persons produce more proinflammatory cytokines such as IL-1, IL-6, and TNF-a in vitro than those from younger ones (48,49).…”

Section: Aging-related Changes To the Innate Immune System-associatedmentioning

confidence: 99%

The Aging Immune System and Its Relationship to the Development of Chronic Obstructive Pulmonary Disease

Sharma¹,

Hanania²,

Shim³

2009

Proceedings of the American Thoracic Society

View full text Add to dashboard Cite

Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory disease of the lungs that usually manifests late in life. Physiologic and immunologic changes that occur in COPD often mimic changes seen in the aging lung. This has led some to characterize COPD as an ''accelerated aging phenotype.'' At the molecular level, COPD and aging share common mechanisms and are associated with significant dysregulation of the immune systems. Aging and COPD are characterized by increases in proinflammatory cytokines such as interleukin (IL)-6 and tumor necrosis factor (TNF)-a, which are implicated in aging-related inflammatory diseases and correlate with degree of obstruction in COPD. There is an age-dependent decline in naïve T cells with oligoclonal expansion of CD8 1 CD28 null T cells from chronic antigenic stimulation. The increase in CD8 1 CD28 null T regulatory cells inhibits antigen-specific CD4 1 T cell responses, leading to a decline in adaptive immune response. To compensate for the decline in the adaptive immune function there is a paradoxical up-regulation of innate immune system resulting in a proinflammatory state. The dysregulated adaptive immune system with activated innate immune responses seen with aging results in recruitment and retention of neutrophils, macrophages, and CD4 1 and CD8 1 T cells in the lungs of smokers with COPD. Once the inflammation is triggered, there is a selfperpetuating cascade of inflammation and lung parenchymal damage. This review will focus on how the aging immune system may contribute to COPD development later in life in susceptible individuals.

show abstract

“…The impact of aging on the expression and function of many of these cell surface proteins is unclear. Aging human and rodent macrophage populations appear to have reduced levels of class II MHC, and it has been suggested that this may contribute to poor T-cell responses (Zissel et al ., 1999;Herrero et al ., 2002). The number of blood monocytes in the elderly and young subjects appears to be very similar; however, there is a significant decrease in the macrophage precursors as well as macrophages in the bone marrow of the elderly ( Takahashi et al ., 1985;Ogawa et al ., 2000).…”

Section: Ontogeny and Distribution Of Macrophagesmentioning

confidence: 99%

Innate immunity in aging: impact on macrophage function

et al. 2004

View full text Add to dashboard Cite

SummaryInnate and adaptive immune functions decline with age, leading to increased susceptibility to infectious diseases and cancer, and reduced responses to preventive vaccination in the elderly population. Macrophages function as 'pathogen sensors' and play an important role in the initiation of inflammatory responses, elimination of pathogens, manipulation of the adaptive immune response and reparation of damaged tissue. In this paper, we review the literature addressing the impact of aging on the macrophage population.

show abstract

Immunosenescence of macrophages: reduced MHC class II gene expression

Cited by 103 publications

References 28 publications

Cutting Edge: Impaired Toll-Like Receptor Expression and Function in Aging

Cutting Edge: Impaired Toll-Like Receptor Expression and Function in Aging

The Aging Immune System and Its Relationship to the Development of Chronic Obstructive Pulmonary Disease

Innate immunity in aging: impact on macrophage function

Contact Info

Product

Resources

About