Accessory Function and Properties of Monocytes from Healthy Elderly Humans for T Lymphocyte Responses to Mitogen and Antigen

Abstract

The waning of cell-mediated immunity during aging has been attributed primarily to defects in T lymphocyte properties and functions. We assessed the potential contribution of accessory dysfunction of monocytes from the elderly on responses of T cells to phytohemagglutinin (PHA) and to tetanus toxoid after in vivo boosting. Accessory function of monocytes from the elderly subjects for T lymphocyte responses to tetanus toxoid was comparable to the young. Expression of the cytokines interleukin-1 interleukin-6 and tumor necrosis factor, the cell adhesion molecules ICAM-1 and LFA-3 and the class II major histocompatibility molecule HLA-DR by monocytes from the elderly and young subjects was similar. T lymphocytes from the elderly responded poorly to PHA. Monocytes from the elderly had a decreased accessory function for PHA-stimulated T cells from young, third donors. Thus, although many accessory properties of monocytes from the elderly are normal, the monocyte and T lymphocyte defects in the elderly for mitogen may represent interactive factors in cell-mediated immunity during aging.

Age‐dependent changes in thymic macrophages and dendritic cells

“…In relation to this, decreased levels of MHC Class II molecules have been described in activated macrophages from aged mice (Herrero et al, 2001) and in monocytes from elderly human subjects (Villanueva et al, 1990). Also, a decreased secretion of IL-1, IL-6, and TNF, as well as an enhanced production of PGE 2 by macrophages have been reported in aged mice (Chen and Bradley, 1993;Effros et al, 1991;Hayek et al, 1997), but not in healthy elderly humans (Fagiolo et al, 1993;Rich et al, 1993).…”

Immune Function and Vaccine Responses in Healthy Advanced Elderly Patients

“…Interleukin 1 production has been normal or decreased in elderly persons, whereas TNF-␣ levels were elevated in the serum samples from elderly subjects in one study 48 but production of TNF-␣ in vitro was normal when compared with young subjects in another. 44,[48][49][50] We showed that in vitro production of TNF-␣, a key cytokine in the immediate inflammatory response to infection, by peripheral blood mononuclear cells with and without stimulation with lipopolysaccharide was not appreciably affected by age. These data are consistent with limited previously published data 51 from this group of elderly and young subjects, among whom plasma levels of TNF-␣, IL-6, IL-10, and transforming growth factor ␤ were all comparable.…”

Differential Oxidative Stress Induced by Dengue Virus in Monocytes from Human Neonates, Adult and Elderly Individuals

“…Decreased plasma membrane fluidity of lymphoid cells and monocytes in advanced age [26], [27] may be one contributor factor to decreased production of NO observed in elderly monocytes, since, it has been reported an association between decreased membrane fluidity in red blood cells of hypertensive patients and low plasma NO-metabolite levels [28]. In addition, monocytes from elderly subjects had a decreased accessory function for PHA-stimulated T cells compare to those obtained from young subjects [13]. Cytokine production and expression of costimulatory T cell proteins (CD80) on monocytes from older adults were lower than those on cells from young individuals [14].…”