Humoral immunity in aging.
The interactions between B and T lymphocytes, leading to the development of humoral responses, are reviewed with references to the changes occurring in aged people. Aging is perceived as a process of impairment of immune functions; it is known that T cells from aged subjects have a reduced ability to produce IL-2. However, other functions seem to be upregulated in elderly subjects; indeed, IL-1, IL-3, IL-4, IL-6 and TNF alpha production are increased both in aged mice and humans. These cytokines are known to control B cell differentiation, through isotype switch and Ig production. A significant increase in IgG subclasses and IgA is observed in sera of aged subjects. This contrasts with the significant decrease in circulating B lymphocytes. The impairment of primary responses to immunization, and other aspects of humoral immunity, including mucosal responses, autoantibody production and correlations with phenotypic markers of T and B cell subsets, are discussed.
Paganelli
R
R
Department of Clinical Immunology, La Sapienza University, Roma, Italy.
Scala
E
E
Quinti
I
I
Ansotegui
I J
IJ
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000276:immunology*; D000818:Animals; D000917:Antibody Formation; D001402:B-Lymphocytes; D016207:Cytokines / Q000276:immunology*; D005260:Female; D006801:Humans; D007114:Immunization; D007136:Immunoglobulins / Q000096:biosynthesis / Q000097:blood / Q000502:physiology*; D018655:Lymphocyte Count; D008297:Male; D012377:Rodentia
D016207:Cytokines; D007136:Immunoglobulins