Expression of c-fos, c-jun and jun B in peripheral blood lymphocytes from young and elderly adults

Lijun song, NIA Gerontology Research Center
Jacqueline M. Stephens, The Brody School of Medicine
Smita Kittur
Gary D. Collins, NIA Gerontology Research Center
James E. Nagel, NIA Gerontology Research Center
Phillip H. Pekala, The Brody School of Medicine
William H. Adler, NIA Gerontology Research Center

Abstract

The expression of c-fos, c-jun and jun B proto-oncogenes was studied in phytohemagglutinin (PHA) activated peripheral blood lymphocytes (PBL) from young and aged humans. Specific mRNAs for c-fos and c-jun were detectable within 30 min after cell activation and reached maximal levels within 2 h. Both c-fos and jun B mRNAs decreased to pre-activation levels within 6 h, while c-jun mRNA remained elevated. In PHA-activated PBL, no age-related differences were observed in c-fos or jun B mRNA expression. However, c-jun mRNA levels decreased significantly (1.73 ± 0.08 vs. 1.16 ± 0.09 arbitrary units, P < 0.01, young vs. old) in PBL from elderly individuals activated with PHA. Because previous work has demonstrated that T cells from elderly individuals may display normal proliferative responses when activated via the anti-CD2 pathway, c-jun and jun B mRNA expression was also studied in anti-CD2-activated purified T cells. No age-related differences were found in the expression of either of these two proto-oncongenes by anti-CD2 activated T cells. These results suggest that the decreased IL-2 production and proliferative response displayed by PHA-activated PBL from elderly adults may be related to age-related changes in c-jun mRNA expression and in the ratio of c-fos to c-jun mRNA. © 1992.