Aging, Idiotype Repertoire Shifts, and Compartmentalization of the Mucosal-Associated Lymphoid System

Age-Related Strain Differences in the Development of Auto-Anti-Idiotypic Antibody Regulation in the Splenic and Mucosal-Associated Lymphoid Systems

“…This suppressive effect of auto-anti-idiotypic antibody was at tributed possibly to its simultaneous binding of surface Ig and Fc receptors on the surface of the B cell, thus inhibiting antibody secre tion [11], In previous studies, we have shown that the decline in the number of plaque forming cells (PFC), loss of high affinity PFC, and the increase in hapten-augmentable PFC with age in the spleen of C57BL/6J male mice may be due to auto-anti-idiotypic anti body regulation [28], In contrast, mucosal immunity in old C57BL/6J mice, as mea sured in PFC responses of the mediastinal (BLN) and mesenteric (MLN) lymph nodes, was not reduced [31]; further, there was no loss of high affinity antibody-secreting cells [30], and there was no appreciable appear ance of anti-idiotype-blocked, hapten-aug mentable PFC [29] in these areas. These find ings support the hypothesis that the systemic and mucosal B cell repertoires do not un dergo parallel changes with age [33].…”

“…Unfortunately, few studies have examined changes within the mucosal immune system during aging or have compared these changes with those in the systemic immune system [reviewed in 32,33]. There is strong evidence to suggest that there is compartmentalization of the mucosal immune system, with the retention of unique cell populations within the gut [reviewed in 33].…”

“…There is strong evidence to suggest that there is compartmentalization of the mucosal immune system, with the retention of unique cell populations within the gut [reviewed in 33]. For example (a) Gearhart and Cebra [8] have shown that dif- [17] demonstrated that after using a mixed immunization protocol (oral and intravenous administration of antigen) of bovine serum albumin, anti-idiotypic plasma cells could be detected in mucosal areas, but not if either immunization route was used alone.…”

“…The loss of immune function that occurs with age has been mainly attributed to an impairment of immunocompetent B and T lymphocytes residing in the spleen [2,3,13,20,21; reviewed in 32,33]. However, others have shown that B cells arising from the bone marrow of old mice have normal prolifera tive responses to B cell mitogens in vitro [5].…”

Thymosin Apha 1–A Peptide Immune Modulator with a Broad Range of Clinical Applications

“…Immune senescence, a normal aging process, has been related to a gradual decline in thymus function and thymic hormone production. The lack of thymic hormones may contribute to the decline in immune function, particularly the T-cell component [176,177]. In the elderly, for example, analysis of a specific antibody response after vaccination has been shown to be impaired when compared with response in young subjects [52,178,179].…”