Pahlavani M A, Harris M D, Richardson A
Geriatric Research Education and Clinical Center, Audie L. Murphy Memorial Veterans Hospital, San Antonio, Texas, USA.
Cell Immunol. 1995 Oct 1;165(1):84-91. doi: 10.1006/cimm.1995.1190.
The effect of aging on the induction of IL-2 transcription by concanavalin A was studied in spleen lymphocytes isolated from young (4-6 months) and old (24 months) male Fischer 344 rats. The induction of IL-2 mRNA levels and IL-2 transcription were 40 to 50% lower for spleen lymphocytes isolated from old rats compared to spleen lymphocytes isolated from young rats. Because the transcription factor NFAT (nuclear factor activating IL-2 transcription) plays a major role in the regulation of IL-2 transcription, the DNA binding activity of NFAT in nuclear extracts of concanavalin A-stimulated lymphocytes was measured using a gel shift assay. The ability of nuclear extracts isolated from either total spleen lymphocytes or T cells to bind the NFAT oligonucleotide decreased 50 to 60% with age. Therefore, the age-related decrease in the expression of IL-2 appears to occur at the level of transcription and involves the transcription factor NFAT.
