Influence of age on the signal transduction of T cells in mice.
A 5- to 10-fold decline was observed in the proliferative activity of T cells stimulated with anti-CD3 mAb between young and old mice. However, the number of CD3 molecules on the T cell surface was almost comparable between young and old T cells. The formation of the second messenger such as inositol triphosphate (IP3) and diacylglycerol (DAG) after mitogenic stimulation decreased in old T cells as compared with young ones. The activity of phospholipase C (PLC), which is responsible for the liberation of IP3 and DAG from phosphatidylinositol-4,5-bisphosphate (PIP2) was not different between young and old T cells. The content of PIP2 in the membrane was also comparable between young and old T cells. These findings have suggested that the age-related decline in the proliferative activity of T cells could be due to impairment of intracellular signal transduction, probably in the pathway somewhere between TCR and PLC.
Utsuyama
M
M
Department of Pathology, Tokyo Metropolitan Institute of Gerontology, Japan.
Varga
Z
Z
Fukami
K
K
Homma
Y
Y
Takenawa
T
T
Hirokawa
K
K
D000375:Aging / Q000502:physiology*; D000818:Animals; D017252:CD3 Complex / Q000378:metabolism; D004075:Diglycerides / Q000378:metabolism; D005434:Flow Cytometry; D015544:Inositol 1,4,5-Trisphosphate / Q000378:metabolism; D008213:Lymphocyte Activation; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D019269:Phosphatidylinositol 4,5-Diphosphate; D018129:Phosphatidylinositol Phosphates / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology*; D013601:T-Lymphocytes / Q000276:immunology / Q000378:metabolism*; D010738:Type C Phospholipases / Q000378:metabolism
D017252:CD3 Complex; D004075:Diglycerides; D019269:Phosphatidylinositol 4,5-Diphosphate; D018129:Phosphatidylinositol Phosphates; D015544:Inositol 1,4,5-Trisphosphate; D010738:Type C Phospholipases