Characteristics of Ig heavy-chain genes from bone marrow and peripheral-blood B-cell populations
Source/B-cell subset* . | No. sequences† . | Mean VH mismatches . | CDR3 length (nucleotide)‡ . | N-addition V-D‡ . | N-addition D-J‡ . | Arginine residues in CDR3‡ . |
|---|---|---|---|---|---|---|
| Bone Marrow | ||||||
| Total NP | 17 | 1.1 ± 1.0 | 65.6 ± 4.1§ | 15.1 ± 2.2§ | 9.4 ± 1.4 | 2.4 ± 0.4§ |
| Pre/pro | 32 | 0.0 | 57.4 ± 3.1 | 9.1 ± 1.2 | 10.0 ± 1.4 | 1.7 ± 0.2 |
| T1 | 26 | 0.0 | 50.0 ± 1.8¶ | 7.3 ± 1.0 | 7.6 ± 1.2∥ | 1.5 ± 0.2∥ |
| Plasma cells | 14 | 18.2 ± 2.5 | 44.4 ± 3.3 | 12.8 ± 4.3 | 7.1 ± 1.6 | 1.4 ± 0.2 |
| Peripheral B cells | ||||||
| Total NP | 30 (19) | 2.1 ± 1.2 | 56.6 ± 3.4§ | 12.0 ± 1.6§ | 7.9 ± 1.7 | 1.7 ± 0.2§ |
| T1 | 44 (21) | 0.1 ± 0.0 | 49.0 ± 2.0∥ | 7.8 ± 0.8 | 5.6 ± 0.7∥ | 1.0 ± 0.1∥ |
| Intermediate | 72 (37) | 0.0 | 48.6 ± 1.5 | 7.5 ± 0.7 | 5.9 ± 0.9 | 1.1 ± 1.1 |
| Mature | 28 (28) | 0.8 ± 0.5 | 49.6 ± 2.4 | 8.8 ± 1.4 | 5.8 ± 0.9 | 1.3 ± 0.2 |
| Memory | 50 (50) | 14.1 ± 1.2 | 42.9 ± 1.4¶ | 7.2 ± 0.7 | 6.1 ± 0.7 | 1.0 ± 0.1 |
Source/B-cell subset* . | No. sequences† . | Mean VH mismatches . | CDR3 length (nucleotide)‡ . | N-addition V-D‡ . | N-addition D-J‡ . | Arginine residues in CDR3‡ . |
|---|---|---|---|---|---|---|
| Bone Marrow | ||||||
| Total NP | 17 | 1.1 ± 1.0 | 65.6 ± 4.1§ | 15.1 ± 2.2§ | 9.4 ± 1.4 | 2.4 ± 0.4§ |
| Pre/pro | 32 | 0.0 | 57.4 ± 3.1 | 9.1 ± 1.2 | 10.0 ± 1.4 | 1.7 ± 0.2 |
| T1 | 26 | 0.0 | 50.0 ± 1.8¶ | 7.3 ± 1.0 | 7.6 ± 1.2∥ | 1.5 ± 0.2∥ |
| Plasma cells | 14 | 18.2 ± 2.5 | 44.4 ± 3.3 | 12.8 ± 4.3 | 7.1 ± 1.6 | 1.4 ± 0.2 |
| Peripheral B cells | ||||||
| Total NP | 30 (19) | 2.1 ± 1.2 | 56.6 ± 3.4§ | 12.0 ± 1.6§ | 7.9 ± 1.7 | 1.7 ± 0.2§ |
| T1 | 44 (21) | 0.1 ± 0.0 | 49.0 ± 2.0∥ | 7.8 ± 0.8 | 5.6 ± 0.7∥ | 1.0 ± 0.1∥ |
| Intermediate | 72 (37) | 0.0 | 48.6 ± 1.5 | 7.5 ± 0.7 | 5.9 ± 0.9 | 1.1 ± 1.1 |
| Mature | 28 (28) | 0.8 ± 0.5 | 49.6 ± 2.4 | 8.8 ± 1.4 | 5.8 ± 0.9 | 1.3 ± 0.2 |
| Memory | 50 (50) | 14.1 ± 1.2 | 42.9 ± 1.4¶ | 7.2 ± 0.7 | 6.1 ± 0.7 | 1.0 ± 0.1 |
Data for productive heavy chain V-D-J rearrangements was derived from pre/pro B cells (CD19+, CD20-/lo, CD38++), T1 B cells (CD19+, CD20hi, CD38++) and plasma cells (CD19-/lo, CD20-, CD38+++) from bone marrow, and T1 B cells (CD20hi, CD10hi, CD44lo), intermediate B cells (CD20hi, CD10+, CD44lo), mature B cells (CD20+, CD10-, CD44hi) and memory B cells (CD19+, CD27+) from peripheral blood. Nonproductive (NP) V-D-J rearrangement data were for the bone marrow B- cell subsets and the peripheral blood B-cell subsets
The number of sequences in brackets were derived from an SLE patient with an abnormally high proportion (17%) and absolute number of T1 B cells. Since there were no significant differences between the healthy donor and the SLE patient with respect to the repertoire or the characteristics of the CDR3, these data were pooled
The mean ± SEM for the CDR3 length, N-addition, and the number of arginines in the CDR3 are given. N-addition was only determined from sequences where a D segment with at least 9 consecutive base matches could be identified. Significant differences were determined using unpaired t tests
The CDR3 length and the mean N-addition at the V-D join of nonproductively rearranged immunoglobulin genes were significantly greater (P < .05) than the productive rearrangements from the combined B-cell subsets
The difference in the CDR3 length between the pro/pre and T1 bone marrow B-cell subsets was not significant (P = .054). However, if the T1 B cells from the bone marrow and peripheral blood were pooled, the CDR3 length and number of arginine residues in the CDR3 were significantly less (P < .05) in the T1 B-cell subset compared with the pro/pre B cells
The CDR3 length was significantly smaller in the memory B-cell population than all other peripheral B-cell subsets