Table 3.
Analysis of peripheral blood B cell subsets before and after rituximab therapy
| Subset | Time Point (week) | Median (cells/μl) | Range (min-max) |
|---|---|---|---|
| Transitional (CD38++, CD27−) | BL | 21.24 | 1.5 – 47.7 |
| 8 | 0.01 | 0.0 – 0.1 | |
| 14 | 0.01 | 0.0 – 0.2 | |
| 26 | 10.30 | 0.1 – 58.3 | |
| 36 | 13.89 | 0.5 – 46.8 | |
| 52 | 21.32 | 7.2 – 49.3 | |
|
| |||
| Mature naïve (CD38+, CD27−) | BL | 134.9 | 18.9 – 280.0 |
| 8 | 0.04 | 0.0 – 0.2 | |
| 14 | 0.02 | 0.0 – 0.1 | |
| 26 | 0.57 | 0.1 – 74.8 | |
| 36 | 37.69 | 0.3 – 96.0 | |
| 52 | 75.94 | 1.4 – 192.7 | |
|
| |||
| Mature activated memory (CD38+, CD27+) | BL | 10.71 | 5.1 – 40.1 |
| 8 | 0.18 | 0.0 – 0.5 | |
| 14 | 0.11 | 0.0 – 0.9 | |
| 26 | 0.60 | 0.3 – 2.0 | |
| 36 | 1.46 | 0.5 – 7.1 | |
| 52 | 2.16 | 1.2 – 23.6 | |
|
| |||
| Mature resting memory (CD38−, CD27+) | BL | 3.69 | 0.0 – 14.9 |
| 8 | 0.02 | 0.0 – 0.1 | |
| 14 | 0.0 | 0.0 – 1.0 | |
| 26 | 0.10 | 0.0 – 0.5 | |
| 36 | 0.25 | 0.1 – 3.5 | |
| 52 | 0.36 | 0.1 – 8.4 | |
|
| |||
| Plasmablast (CD38++, CD27++) | BL | 1.01 | 0.3 – 3.9 |
| 8 | 0.06 | 0.0 – 2.3 | |
| 14 | 0.06 | 0.0 – 0.5 | |
| 26 | 0.24 | 0.0 – 1.1 | |
| 36 | 0.43 | 0.0 – 5.0 | |
| 52 | 0.78 | 0.2 – 15.9 | |
|
| |||
| Double negative (CD38−, CD27−) | BL | 4.28 | 1.3 – 7.4 |
| 8 | 1.54 | 0.0 – 3.6 | |
| 14 | 0.76 | 0.0 – 3.5 | |
| 26 | 0.87 | 0.0 – 6.5 | |
| 36 | 1.47 | 0.6 – 5.0 | |
| 52 | 1.28 | 0.4 – 8.7 | |
Fresh whole blood (less than 24 hours old) was analyzed by flow cytometry as described in Materials and Methods. To calculate the B cell subset absolute cell counts the absolute lymphocyte count (in cells per microliter of whole blood) was obtained by Coulter counting or through the complete blood count at each of the local sites. The B cell fraction was obtained by multiplying the absolute lymphocyte count by the CD19+ fraction. B cell subset counts were computed by multiplying the B cell absolute count by the fraction of B cells in each of the subsets. The B cell subsets were defined using CD38 and CD27 staining into the following subsets: transitional (CD38++, CD27−), mature naïve (CD38+, CD27−), mature activated memory (CD38+, CD27+), resting memory (CD38−, CD27+), plasmablast (CD38++, CD27++), and double negative (CD38−, CD27−), as described previously (21, 22). B cell subset data are not available for subject 08-096 at the baseline time point and not available for subject 04-098 at the week 26 time point. Time points are defined in weeks following rituximab administration.
BL = baseline.