Aging reduces the primary humoral response and the in vitro cytokine production in mice

Abstract

Aging is accompanied by a decrease in several physiological functions that make older individuals less responsive to environmental challenges. In the present study, we analyzed the immune response of female BALB/c mice (N = 6) of different ages (from 2 to 96 weeks) and identified significant age-related alterations. Immunization with hapten-protein (trinitrophenyl-bovine serum albumin) conjugates resulted in lower antibody levels in the primary and secondary responses of old mice (72 weeks old). Moreover, young mice (2, 16, and 32 weeks old) maintained specific antibodies in their sera for longer periods after primary immunization than did old mice. However, a secondary challenge efficiently induced memory in old mice, as shown by the increased antibody levels in their sera. The number of CD4 + and CD8 + T cells in the spleen increased until 8 weeks of age but there was no change in the CD4 + /CD8 + ratio with aging. Splenic T cells from old mice that had or had not been immunized were less responsive to concanavalin-A and showed reduced cytokine production compared to young mice (IL-2: 57-127 vs 367-1104 pg/mL, IFN-γ: 2344-12,836 vs 752-23,106 pg/mL and IL-10: 393-2172 vs 105-2869 pg/mL in old and young mice, respectively). These data suggest that there are significant changes in the organization of the immune system throughout life. However, the relevance of these alterations for the functioning of the immune system is unknown.

Effect of aging and oral tolerance on dendritic cell function

“…These results suggest that the establishment of immunity is easier in younger animals, supporting previous literature data (10,24,28,29). Tolerance was well preserved in all groups of mice studied.…”

“…Mice were housed under pathogen-free conditions and fed a diet of autoclaved food and water. BALB/c mice were classified into five age groups (N = 5 in each group): young (8 weeks of age), adults (20 weeks of age), middle-aged (40 weeks of age), old (60 weeks of age), and very old (80 weeks of age) mice based on the results of previous research on age-related antibody and cytokine decrease (10). The study was approved by the Institutional Ethics Committee for Animal Experimentation (Protocol #594-1).…”

“…Senescence of the immune system leads to a decline in the responses to exogenous antigens as well as in the susceptibility to tolerance (9)(10)(11). The alterations observed in immunosenescence are attributed, at least in part, to the changes in maturation of T and B lymphocytes (11,12).…”

Aging of the CD4 T Cell Compartment

“…But this is problematic since the efficacy of vaccines for influenza or Streptococcus pneumonia , for example, is greatly reduced in people over 65 years of age [5,6]. Similarly, old mice show a decreased antibody response following vaccination for a variety of antigens [7,8]. This poor response to immunization, as well as the increased susceptibility to infections in the elderly, reflects the decline in the immune system functions with aging.…”

Influence of Age on Susceptibility to Pseudomonas aeruginosa Exotoxin A-induced Hepatotoxicity in Long-Evans Rats

“…Age-related changes in immune and physiological functions in humans and laboratory rodents have been extensively investigated [13,20]. Many studies have noted that subject age is a critical factor in many experimental models of liver disease, such as acetaminophen, carbon tetrachloride, lipopolysaccharide (LPS), α-galactosylceramide, and cadmium-induced liver injury [5,9,15,22,23,26].…”