Mouse liver T cells: their change with aging and in comparison with peripheral T cells.
Mouse liver contains both IL-2Rbeta- (or low positive) high T-cell receptor (TCR(hi)) cells and IL-2Rbeta+ intermediate TCR (TCR(int)) cells. TCR(int) cells consist of natural killer 1.1 (NK1)+ and NK1- subsets. NK1- TCR(int) cells increase constantly with age whereas TCR(hi) cells decrease. NK1+ TCR(int) cell proportions in the liver increase until middle age and decrease thereafter. Although NK1+ TCR(int) cells in other organs are few regardless of age, NK1- TCR(int) cells gradually appear in other lymphoid organs with aging. Skewed usage of Vbeta7 and Vbeta8 TCR was observed in NK1+ TCR(int) cells in the liver but the predominance was less obvious in NK1- TCR(int) and TCR(hi) cells in the liver and other organs. TCR V alpha14 messenger RNA (mRNA) was detected in NK1+ TCR(int) cells but not in the other two populations. In contrast, although NK1+ TCR(int) cells contain virtually no V alpha11+ T cells, NK1- TCR(int) cells contain a much higher proportion (approximately 12%) of V alpha11+ T cells, whereas approximately 4% of TCR(hi) cells are V alpha11+. NK activities of liver mononuclear cells (MNC) and splenocytes decrease with aging, although the former is always greater than the latter. NK activity of liver MNC is a function of NK cells, partly NK1+ TCR(int) cells but not NK1- TCR(int) cells or TCR(hi) cells. These results suggest that lymphocytes of liver and other organs at old age are no longer occupied solely by conventional thymus-derived T cells, and the increase of extrathymic IL-2Rbeta+ NK1- TCR(int) cells in liver and periphery could be closely related to immunological changes with aging.
Tsukahara
A
A
1st Department of Surgery, Niigata University School of Medicine, Asahimachi, Japan.
Seki
S
S
Iiai
T
T
Moroda
T
T
Watanabe
H
H
Suzuki
S
S
Tada
T
T
Hiraide
H
H
Hatakeyama
K
K
Abo
T
T
D000375:Aging / Q000276:immunology*; D000818:Animals; D017252:CD3 Complex / Q000032:analysis; D003602:Cytotoxicity, Immunologic; D016130:Immunophenotyping; D007694:Killer Cells, Natural / Q000276:immunology; D008099:Liver / Q000166:cytology / Q000276:immunology*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000032:analysis; D013601:T-Lymphocytes / Q000276:immunology*
D017252:CD3 Complex; D016693:Receptors, Antigen, T-Cell, alpha-beta