Proliferation and disappearance rates of B cells in young and elderly healthy subjects
. | . | Proliferation . | . | Disappearance . | . | ||
|---|---|---|---|---|---|---|---|
| Subject . | Age, y . | p . | t2, d . | d* . | t1/2, d . | ||
| Young subjects | |||||||
| C02 | 26 | 1.14 | 60.8 | 1.11 | 62.4 | ||
| C03 | 21 | 3.28 | 21.1 | 9.05 | 7.7 | ||
| C04 | 24 | 1.17 | 59.2 | 0.00 | -† | ||
| C05 | 21 | 2.63 | 26.4 | 5.09 | 13.6 | ||
| C06 | 34 | 3.34 | 20.8 | 5.65 | 12.3 | ||
| C07 | 22 | 0.97 | 71.5 | 0.00 | -† | ||
| C08 | 33 | 0.93 | 74.5 | 3.45 | 20.1 | ||
| C10 | 19 | 1.94 | 35.7 | 7.19 | 9.6 | ||
| Mean | 25 | 1.93 | 36.0* | 3.94 | 17.6* | ||
| SD | 6 | 1.03 | NA | 3.39 | NA | ||
| Elderly subjects | |||||||
| E01 | 75 | 0.48 | 144.4 | 0.00 | -† | ||
| E01R | 77 | 0.55 | 126.0 | 2.98 | 23.3 | ||
| E02 | 85 | 1.55 | 44.7 | 3.35 | 20.7 | ||
| E04 | 85 | 0.75 | 92.4 | 4.9 | 14.1 | ||
| E05 | 70 | 1.34 | 51.7 | 5.77 | 12.0 | ||
| E06 | 65 | 2.48 | 27.9 | 7.52 | 9.2 | ||
| E07 | 79 | 0.09 | 770.2 | 0.00 | 195† | ||
| E08 | 77 | 4.03 | 17.2 | 11.98 | 5.8 | ||
| Mean | 77 | 1.54 | 45.0* | 5.21 | 13.3* | ||
| SD | 7 | 1.34 | NA | 3.81 | NA | ||
. | . | Proliferation . | . | Disappearance . | . | ||
|---|---|---|---|---|---|---|---|
| Subject . | Age, y . | p . | t2, d . | d* . | t1/2, d . | ||
| Young subjects | |||||||
| C02 | 26 | 1.14 | 60.8 | 1.11 | 62.4 | ||
| C03 | 21 | 3.28 | 21.1 | 9.05 | 7.7 | ||
| C04 | 24 | 1.17 | 59.2 | 0.00 | -† | ||
| C05 | 21 | 2.63 | 26.4 | 5.09 | 13.6 | ||
| C06 | 34 | 3.34 | 20.8 | 5.65 | 12.3 | ||
| C07 | 22 | 0.97 | 71.5 | 0.00 | -† | ||
| C08 | 33 | 0.93 | 74.5 | 3.45 | 20.1 | ||
| C10 | 19 | 1.94 | 35.7 | 7.19 | 9.6 | ||
| Mean | 25 | 1.93 | 36.0* | 3.94 | 17.6* | ||
| SD | 6 | 1.03 | NA | 3.39 | NA | ||
| Elderly subjects | |||||||
| E01 | 75 | 0.48 | 144.4 | 0.00 | -† | ||
| E01R | 77 | 0.55 | 126.0 | 2.98 | 23.3 | ||
| E02 | 85 | 1.55 | 44.7 | 3.35 | 20.7 | ||
| E04 | 85 | 0.75 | 92.4 | 4.9 | 14.1 | ||
| E05 | 70 | 1.34 | 51.7 | 5.77 | 12.0 | ||
| E06 | 65 | 2.48 | 27.9 | 7.52 | 9.2 | ||
| E07 | 79 | 0.09 | 770.2 | 0.00 | 195† | ||
| E08 | 77 | 4.03 | 17.2 | 11.98 | 5.8 | ||
| Mean | 77 | 1.54 | 45.0* | 5.21 | 13.3* | ||
| SD | 7 | 1.34 | NA | 3.81 | NA | ||
Proliferation (p) and disappearance (d*) rate constants modeled for B cells sorted according to CD19 expression expressed as percent per day. t2 and t1/2 represent doubling time or half-life equivalents of respective p and d* values for each subject. E01 was studied twice, but the elderly average values include only 1 set of values (E01R) from this subject; E01 (italics) excluded. E04 estimates of p and d* are based on 2 data points only. No significant differences, except for age, were detected between elderly and young subjects by Student 2-tailed t test.
NA indicates not applicable.
indicates doubling time or half-life equivalent of mean values for p and d* rather than mean of individual values, which are highly skewed, so no SD is shown
indicates doubling time or half-life not estimable, as it exceeds maximal value detectable (p or d* close to zero)