Quantitative dynamics of thymic and extrathymic T-cell proliferation in vitro
. | CD4+ . | . | CD8+ . | . | ||
|---|---|---|---|---|---|---|
. | Anti-CD3 . | Anti-CD3 + anti-CD28 . | Anti-CD3 . | Anti-CD3 + anti-CD28 . | ||
| Thymic T cells | ||||||
| Burst size, n | 3.4 ± 0.9 | 5.8 ± 0.8 | 6.7 ± 2.3 | 10.8 ± 1.7 | ||
| Doubling time, h | 43.3 ± 9.9 | 28.8 ± 2.4 | 28.0 ± 6.1 | 21.1 ± 1.4 | ||
| Expansion, x-fold | 1.3 ± 0.3 | 1.7 ± 0.9 | 1.9 ± 0.9 | 5.7 ± 3.5 | ||
| Extrathymic T cells | ||||||
| Burst size, n | 4.3 ± 0.6* | 6.2 ± 2.1 | 18.8 ± 5.1† | 18.0 ± 3.7† | ||
| Doubling time, h | 34.9 ± 3.2 | 28.7 ± 5.1 | 17.3 ± 1.8* | 17.5 ± 1.3† | ||
| Expansion, x-fold | 0.6 ± 0.1† | 0.8 ± 0.4* | 5.6 ± 1.8* | 4.7 ± 1.0 | ||
. | CD4+ . | . | CD8+ . | . | ||
|---|---|---|---|---|---|---|
. | Anti-CD3 . | Anti-CD3 + anti-CD28 . | Anti-CD3 . | Anti-CD3 + anti-CD28 . | ||
| Thymic T cells | ||||||
| Burst size, n | 3.4 ± 0.9 | 5.8 ± 0.8 | 6.7 ± 2.3 | 10.8 ± 1.7 | ||
| Doubling time, h | 43.3 ± 9.9 | 28.8 ± 2.4 | 28.0 ± 6.1 | 21.1 ± 1.4 | ||
| Expansion, x-fold | 1.3 ± 0.3 | 1.7 ± 0.9 | 1.9 ± 0.9 | 5.7 ± 3.5 | ||
| Extrathymic T cells | ||||||
| Burst size, n | 4.3 ± 0.6* | 6.2 ± 2.1 | 18.8 ± 5.1† | 18.0 ± 3.7† | ||
| Doubling time, h | 34.9 ± 3.2 | 28.7 ± 5.1 | 17.3 ± 1.8* | 17.5 ± 1.3† | ||
| Expansion, x-fold | 0.6 ± 0.1† | 0.8 ± 0.4* | 5.6 ± 1.8* | 4.7 ± 1.0 | ||
Splenocytes from B6 mice (thymic T cells) and from OM → B6.SJL chimeras (extrathymic T cells) were labeled with CFSE and stimulated with anti-CD3 with or without anti-CD28. After 72 hours, cells were labeled with 7-AAD and stained with antibodies against CD4, CD8, Ly5.1, and Ly5.2 (mean ± SD for 5 experiments). Burst size is the number of daughter cells/number of dividing precursor cells. Doubling time is t × In2/In burst size. Expansion is the number of cells at 72 hours/number of cells at 24 hours. Student t test was used for P values.
P < .05.
P < .01.