Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.

Site Tools

  • AAAS
  • Subscribe
  • Feedback

Site Search

Search Advanced

Science 20 December 1996:
Vol. 274. no. 5295, pp. 2092 - 2094
DOI: 10.1126/science.274.5295.2092
Prev | Table of Contents | Next

Reports

Reexpression of RAG-1 and RAG-2 Genes in Activated Mature Mouse B cells

Masaki Hikida, Masaharu Mori, Toshiyuki Takai, Ken-ichi Tomochika, Kiyohiro Hamatani, Hitoshi Ohmori *

Recombination activating genes (RAG-1 and RAG-2), involved in V(D)J rearrangement of immunoglobulin genes, have been thought to be expressed only in immature stages of B-cell development. However, RAG-1 and RAG-2 transcripts were found to be reexpressed in mature mouse B cells after culture with interleukin-4 in association with several different co-stimuli. Reexpression was also detected in draining lymph nodes from immunized mice. RAG-1 and RAG-2 proteins could be detected by immunofluorescence microscopy in the nuclei of B cells cultured in vitro and in the germinal centers of draining lymph nodes. These findings suggest that RAG gene products play a heretofore unsuspected role in mature B cells.

M. Hikida, T. Takai, H. Ohmori, Department of Biotechnology, Faculty of Engineering, Okayama University, Tsushima-Naka, Okayama 700, Japan.
M. Mori, Faculty of Health and Welfare Sciences, Okayama Prefectural University, Soja 719-11, Japan.
K. Tomochika, Faculty of Pharmaceutical Sciences, Okayama University, Okayama 700, Japan.
K. Hamatani, Radiation Effects Research Foundation (Hiroshima), Hiroshima 732, Japan.
*   To whom correspondence should be addressed. E-mail: hit2224{at}cc.okayama-u.ac.jp

The rearrangement of immunoglobulin (Ig) and T cell receptor (TCR) genes is a crucial step in the maturation process of B cells and T cells. Recombination of Ig and TCR genes is catalyzed by the products of the two recombination activating genes, RAG-1 and RAG-2 (1, 2, 3). A defect in either RAG-1 or RAG-2 results in the retention of Ig and TCR loci in germline configuration and blocks the development of mature lymphocytes (4). RAG-1 and RAG-2 have been considered to be expressed exclusively in immature lymphocytes in bone marrow and thymus, being readily down-regulated in mature lymphocyte populations, such as IgD+ B cells and TCR+ T cells (2, 5, 6). RAG expression in early B cells occurs in two waves, the first being responsible for V(D)J (V, variable; D, diversity; J, joining) rearrangement of Ig heavy-chain genes in proB and preB-I cells and the second for VJ recombination of Ig light-chain genes in small preB-II cells (5). We describe a third wave of RAG-1 and RAG-2 expression, induced in activated mature B cells in vitro and in vivo.

Spleen B cells from C3H/HeN mice cultured for 2 days with lipopolysaccharide (LPS) plus interleukin-4 (IL-4) expressed RAG-1 and RAG-2, as assessed by the combination of reverse transcriptase-polymerase chain reaction (RT-PCR) and Southern (DNA) blotting (Fig. 1A). The presence of bands of correct size was strictly dependent on RT, indicating that PCR-amplified materials were not derived from contaminated genomic DNA. RAG-1 and RAG-2 expression was not detected in the cells before the culture, in unstimulated B cells, and in cells stimulated with either LPS or IL-4 alone. LPS combined with other cytokines--including IL-2, IL-3, or IL-5--was ineffective (7). To confirm that surface IgD+ (sIgD+) mature B cells respond to LPS plus IL-4, we undertook similar experiments in B cells purified by panning on plates coated with monoclonal antibody (mAb) to IgD (Fig. 1B). These enriched B-cell preparations also expressed RAG genes in response to LPS plus IL-4.


Fig. 1. (A) Expression of RAG-1 and RAG-2 mRNA in splenic B cells stimulated with LPS and IL-4. Mouse spleen B cells were cultured with LPS plus IL-4 for 2 days (19), and assessed for RAG expression by PCR with (+) or without (-) undergoing prior reverse transcription (RT). Amplified products were visualized by Southern (DNA) blotting (18). Lane 1, uncultured B cells; lane 2, no stimuli; lane 3, IL-4; lane 4, LPS; lane 5, LPS plus IL-4; and lane 6, positive control (thymocytes). IL-4-dependent RAG expression was observed reproducibly in at least 10 separate experiments, and a representative result is shown. (B) Purified sIgD+B cells express RAG-1 and RAG-2 mRNA when stimulated with LPS and IL-4. sIgD+B cells were purified by panning on culture plates coated with mAb to IgD (20) and stimulated with (lane 2) or without (lane 1) LPS plus IL-4 as described above. Lane 3 shows the positive control (thymocytes). (C) Effects of various B-cell stimuli on the induction of RAG-1 and RAG-2 expression. Mouse spleen B cells were cultured for 2 days with the following stimuli (19): Lane 1, no stimuli; lane 2, IL-4; lane 3, LPS plus IL-4; lane 4, mAb to CD40 plus IL-4; lane 5, antibody to µ heavy chain, 8-mercaptoguanosine, and IL-4; and lane 6, positive control (thymocytes). [View Larger Versions of these Images (41K GIF file)]

Various stimuli other than LPS were examined for their capacity to elicit the expression of RAG genes in the presence of IL-4 (Fig. 1C). Monoclonal antibody to CD40 was as effective as LPS, and antibody to µ heavy chain plus 8-mercaptoguanosine, a potent B-cell activator (8), was also effective; both these stimuli were ineffective in the absence of IL-4. The same stimuli--IL-4 with LPS, with mAb to CD40 and with antibody to µ heavy chain plus 8-mercaptoguanosine--also cause B cells to switch the isotype of secreted Igs from IgM to IgG1 and IgE (9). Thus, it is likely that Ig class switching and RAG expression require a similar B-cell activation status.

Can in vitro RAG expression be reproduced in vivo? Mice were immunized with the antigen trinitrophenyl-keyhole limpet hemocyanin (TNP-KLH) in the hind footpads, and the draining lymph nodes (LN) were examined for the expression of RAG-1 and RAG-2. Inguinal and popliteal LN cells expressed these gene transcripts on day 6 and day 8 postimmunization (Fig. 2).

Fig. 2. Expression of RAG-1 and RAG-2 in draining LN of TNP-KLH-immunized mice. Mice were immunized with TNP-KLH in the hind footpads (19). Inguinal LN cells were assessed for RAG expression on day 0, 6, and 8 postimmunization, as indicated in Fig. 1 (18). Lane 1, day 0; lane 2, day 6; lane 3, day 8; and lane 4, positive control (thymocytes). [View Larger Version of this Image (30K GIF file)]

To further confirm RAG gene expression, we performed immunofluorescence microscopy, using mAbs to RAG-1 and RAG-2 (Fig. 3). These mAbs detected RAG-1 and RAG-2 proteins in mouse thymocytes used as a positive control (5, 10). More than 80% of the B cells that were stimulated in vitro with LPS plus IL-4 stained with both mAbs; unstimulated B cells and isotype-matched control mAb showed no positive immunofluorescence. RAG-1- and RAG-2-positive cells were not detected before culture. About 70% of the B cells used were recovered as viable cells at the end of the culture period. Taken together, these observations suggest that the development of RAG-expressing cells was not due to the expansion of a small number of immature B cells possibly present in the initial B cell preparation.

Fig. 3. Immunofluorescence analysis of RAG-1 and RAG-2 expression in cultured B cells and in draining LN. (A) Isolated thymocytes, B cells cultured without stimuli, and B cells stimulated with LPS plus IL-4 for 2 days (19) were reacted with biotinylated irrelevant IgG2b, mAb to RAG-1, or mAb to RAG-2, followed by staining with rhodaminated avidin (21). (B) Cryosections of inguinal LN from mice immunized with TNP-KLH and alum (19) were prepared on day 8 postimmunization and were reacted with biotinylated mAb to RAG-1, followed by double-staining with rhodaminated avidin and FITC-PNA (21). Irrelevant IgG2b gave much weaker rhodamine fluorescence. (Left), FITC-PNA; (middle), mAb to RAG-1; (right), superimposed image of (left) and (middle). Magnification ×200. [View Larger Version of this Image (132K GIF file)]

Cryosections of draining LN from mice immunized with TNP-KLH were stained with mAb to RAG-1 (Fig. 3B). RAG-1-positive cells were detected in inguinal and popliteal LN sections. Germinal center (GC) B cells were clearly visualized by staining with fluorescein isothiocyanate-conjugated peanut agglutinin (FITC-PNA) (11). RAG-1 products appeared to be expressed almost exclusively within the FITC-PNA-binding GC populations and were not present in the marginal zone around GC. PNA- and RAG-1-positive cells were not detected in the unimmunized LN sections. Further, an observation has been made which suggests that RAG genes are expressed in tingible body cells in GC (12).

It has been reported that RAG genes are expressed in some sIg-positive B cell lines with some mature phenotypes (13), and a trace amount of RAG transcripts was detected in normal mouse lymphoid tissues (14). The latter may have been because of a small number of immature B cells. However, we have now shown that significant RAG-1 and RAG-2 gene expression occurs, both in primary culture of mature B cells and in the peripheral lymphoid tissues of immunized animals.

In mice transgenic for genes encoding autoantibodies to DNA (15) or H-2K (16), B cells that escaped deletion after encountering the self antigen bear altered sIg receptors. These receptor modifications (termed receptor editing) were shown to accompany RAG expression in bone marrow cells, and are believed to contribute to the removal of autoreactive B cells during earlier developmental stages (16).

It is interesting to note that RAG expression was induced by an antigen in GC where Ig class switching, somatic hypermutations, and the selection process for affinity maturation take place (17). Although further investigations are necessary to prove that RAG gene products induced under these experimental conditions are functional, it is possible that RAG-dependent revision of Ig genes can occur in mature B cells.

REFERENCES AND NOTES

  1. J. Hagman and R. Grosschedl, Curr. Opin. Immunol. 6, 222 (1994) [Medline].
  2. A. Wilson, W. Held, H. R. MacDonald, J. Exp. Med. 179, 1355 (1994).
  3. J. F. McBlane et al., Cell 83, 387 (1995) [Medline]; C. B. Thompson, Immunity 3, 531 (1995) [Medline].
  4. Y. Shinkai et al., Science 259, 822 (1993) [Medline]; P. Mombaerts et al., Cell 68, 869 (1992) [Medline]; Y. Shinkai et al., ibid., p. 855.
  5. U. Grawunder et al., Immunity 3, 601 (1995) [Medline].
  6. P. Ghia et al., Eur. J. Immunol. 25, 3108 (1995) [Medline].
  7. M. Hikida and H. Ohmori, unpublished data.
  8. M. G. Goodman and W. O. Weigle, J. Immunol. 130, 2580 (1983) [Medline].
  9. C. M. Snapper, F. D. Finkelman, W. E. Paul, J. Exp. Med. 167, 183 (1988) [Medline]; T. Kawabe et al., Immunity 1, 167 (1994) [Medline]; M. Hikida, T. Takai, H. Ohmori, J. Immunol. 156, 2730 (1996) [Medline].
  10. E. Spanopoulou et al., Immunity 3, 715 (1995) [Medline].
  11. M. L. Rose et al., Nature 284, 364 (1980) [Medline]; J. Jacob, R. Kassir, G. Kelsoe, J. Exp. Med. 173, 1165 (1991) [Medline].
  12. H. Ohmori, M. Mori, M. Hikida, in preparation.
  13. A. Ma, P. Fisher, F. Alt, EMBO J. 11, 2727 (1992) [Medline]; L. K. Verkoczy, B. J. Stiernholm, N. L. Berinstein, J. Immunol. 154, 5136 (1995) [Medline].
  14. J. J. M. Chun et al., Cell 64, 189 (1991) ; A. Yamamoto, M. Atsuta, K. Hamatani, Cell. Biochem. Funct. 10, 71 (1992) [Medline]; M. Abe et al., Int. Immunol. 3, 105 (1991) .
  15. M. Z. Radic, J. Erikson, S. Litwin, M. Weigert, J. Exp. Med. 177, 1165 (1993) [Medline]; C. Chen et al., J. Immunol. 152, 1970 (1994) [Medline]; C. Chen, Z. Nagy, E. L. Prak, M. Weigert, Immunity 3, 747 (1995) [Medline].
  16. S. L. Tiegs, D. M. Russell, D. Nemazee, J. Exp. Med. 177, 1009 (1993) [Medline].
  17. K. Rajewsky, Nature 381, 751 (1996) [Medline].
  18. Total RNA was extracted from 1 × 106 cultured B cells by the RNA Zol B method as described [ P. Chomczynski and N. Sacchi, Anal. Biochem. 162, 156 (1987) [Medline]]. The extracted RNA preparations were reverse transcribed, and the resultant cDNA was amplified by PCR with the following sense and antisense primers: 5'-ATGGCTGCCTCCTTGCCGTCT-3' and 5'-GTATCTCCGGCTGTGCCCGTC-3' for RAG-1, 5'-ATGTCCCTGCAGATGGTAACA-3' and 5'-TAAATCTTATCGGAAAGCTCA-3' for RAG-2, and 5'-CCATCACCATCTTCCAGGAG-3' and 5'-CCTGCTTCACCACCTTCTTG-3' for GAPDH. PCR conditions were 27 cycles of 1 min at 95°C, 2 min at 60°C, and 2 min at 72°C for RAG-1 and RAG-2; and 20 cycles of 30 s at 95°C, 30 s at 60°C, and 30 s at 72°C for glyceraldehyde phosphate dehydrogenase (GAPDH). These PCR cycles were confirmed to be in the exponential phase of the amplification. PCR products were electrophoresed on 7.5% polyacrylamide gel and visualized by Southern (DNA) blotting using 32P-labeled probes, the Dde I-Dde I 163-base pair (bp) internal fragment of RAG-1 cDNA, the Pst I-HinfI 124-bp internal fragment of RAG-2 cDNA, and the entire coding region of GAPDH cDNA. Hybridized filters were exposed to Fuji imaging plate (Fuji Film) for 2 days and visualized by a Bioimaging Analyzer, BAS 1000 (Fuji Film). RAG-1 and RAG-2 cDNAs were given by D. G. Schatz (Yale University, New Haven, CT).
  19. Mouse B cells were prepared by treating spleen cells from male C3H/HeN mice (8 to 10 weeks of age, Japan Charles River) with 1/1000-diluted mAb to Thy 1.2 mAb (SeroTec), followed by incubation with low-toxic rabbit complement (Cederlane) as described [ K. Haruna et al., Cell. Immunol. 151, 52 (1993) [Medline]]. The B cells (3 × 106 cells per milliliter) were cultured with LPS (20 µg/ml) from Escherichia coli 055 B5 (Sigma) and mouse recombinant IL-4 (500 U/ml; PeproTech) in 1 ml of RPMI-1640 medium containing 10% fetal bovine serum, 10 µM 2-mercaptoethanol, penicillin G (100 U/ml), and streptomycin (50 µg/ml). In some cases, mAb to mouse CD40 (1 µg/ml; rat mAb LB429 presented by N. Sakaguchi, Kumamoto University, Japan) or F(ab')2 fragment of goat antibody to mouse µ heavy chain (10 µg/ml; Cosmo Bio) plus 1 mM 8-mercaptoguanosine (Sigma) was used as a stimulus. Because it was confirmed that RAG expression peaked on day 2 of the culture and declined thereafter, all cultures were carried out for 2 days. In in vivo experiments, mice were immunized with 20 µg of TNP-KLH and 0.45 mg of alum in each hind footpad. Inguinal or popliteal LN cells from three mice were pooled on day 0, 6, and 8 postimmunization and assessed for the expression of RAG-1 and RAG-2 mRNA (18).
  20. Culture plates of 100 mm diameter were coated with 100 µg/ml of mAb to mouse IgD (Biosys). Sixty million mouse spleen cells that had been depleted of T cells and erythrocytes were placed in the plate and incubated for 1 hour at room temperature. Then the plate was gently washed with phosphate-buffered saline four times to remove nonadherent cells. It was confirmed by flow cytometric analysis (FACScan) that adherent cells recovered from the plate were more than 99% positive for sIgD and B220.
  21. Monoclonal antibodies to mouse RAG-1 (G109-256.2, mouse IgG2b) and RAG-2 (G110-461, mouse IgG2b) were obtained from Pharmingen. A myeloma-derived murine IgG2b (MOPC 195) was used as an irrelevant negative control (ICN Biomedicals). These mAbs were biotinylated under the same conditions, using a biotinylation kit (American Qualex). Staining of RAG proteins in thymocytes or cultured B cells was carried out as described (10), with some modifications. Briefly, the cultured cells were fixed on glass slides in methanol-acetone (1:1) for 5 min, rehydrated in phosphate-buffered saline, and preblocked for 1 hour with TBST [10 mM tris (pH 8.0), 150 mM NaCl, and 0.05% Tween 20] containing 1% bovine serum albumin (BSA) and MOPC 195 (50 µg/ml). The slides were then incubated in TBST containing 1% BSA and one of each biotinylated mAb (5 µg/ml) for 1 hour at room temperature. Slides were then washed three times in TBST and reacted for 1 hour with rhodaminated avidin (2 µg/ml; Sigma) in TBST containing 1% BSA. For the immunofluorescent staining of LN sections, 6-µm-thick cryosections mounted on slides were allowed to air dry for 15 min and were fixed in ice-cold acetone for 10 min. After rehydration and preblocking as described above, the sections were treated with biotinylated anti-RAG-1 (5 µg/ml) for 1 hour, followed by double-staining with rhodaminated avidin (2 µg/ml) and FITC-PNA (4 µg/ml; Seikagaku Kogyo) for 40 min. All reagents were diluted in TBST containing 1% BSA. After washing with TBST, samples were finally mounted with low-fluorescent glycerol and cover slip protection, and were observed with a Zeis fluorescence microscope.
  22. This work was supported in part by a grant-in-aid from the Ministry of Education, Science and Culture of Japan. We thank H. Kagawa for excellent secretarial assistance.

10 June 1996; accepted 10 October 1996


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Exclusion of Natural Autoantibody-Producing B Cells from IgG Memory B Cell Compartment during T Cell-Dependent Immune Responses.
A. Matejuk, M. Beardall, Y. Xu, Q. Tian, D. Phillips, B. Alabyev, K. Mannoor, and C. Chen (2009)
J. Immunol. 182, 7634-7643
   Abstract »    Full Text »    PDF »
Patterns of Receptor Revision in the Immunoglobulin Heavy Chains of a Teleost Fish.
M. D. Lange, G. C. Waldbieser, and C. J. Lobb (2009)
J. Immunol. 182, 5605-5622
   Abstract »    Full Text »    PDF »
Oncogenic transformation in the absence of Xrcc4 targets peripheral B cells that have undergone editing and switching.
J. H. Wang, F. W. Alt, M. Gostissa, A. Datta, M. Murphy, M. B. Alimzhanov, K. M. Coakley, K. Rajewsky, J. P. Manis, and C. T. Yan (2008)
J. Exp. Med. 205, 3079-3090
   Abstract »    Full Text »    PDF »
Epstein-Barr virus and Burkitt lymphoma.
G Brady, G J MacArthur, and P J Farrell (2008)
Postgrad. Med. J. 84, 372-377
   Abstract »    Full Text »    PDF »
Antigen Receptor Editing in Anti-DNA Transitional B Cells Deficient for Surface IgM.
K. Kiefer, P. B. Nakajima, J. Oshinsky, S. H. Seeholzer, M. Radic, G. C. Bosma, and M. J. Bosma (2008)
J. Immunol. 180, 6094-6106
   Abstract »    Full Text »    PDF »
Epstein Barr virus and Burkitt lymphoma.
G Brady, G J MacArthur, and P J Farrell (2007)
J. Clin. Pathol. 60, 1397-1402
   Abstract »    Full Text »    PDF »
Transitional B Cells Lose Their Ability to Receptor Edit but Retain Their Potential for Positive and Negative Selection.
H. Wang, J. Feng, C.-F. Qi, Z. Li, H. C. Morse III, and S. H. Clarke (2007)
J. Immunol. 179, 7544-7552
   Abstract »    Full Text »    PDF »
IL-6 Contributes to the Expression of RAGs in Human Mature B Cells.
S. Hillion, M. Dueymes, P. Youinou, and C. Jamin (2007)
J. Immunol. 179, 6790-6798
   Abstract »    Full Text »    PDF »
Replication history of B lymphocytes reveals homeostatic proliferation and extensive antigen-induced B cell expansion.
M. C. van Zelm, T. Szczepanski, M. van der Burg, and J. J.M. van Dongen (2007)
J. Exp. Med. 204, 645-655
   Abstract »    Full Text »    PDF »
Differential expression patterns of recombination-activating genes in individual mature B cells in juvenile idiopathic arthritis.
C Faber, H Morbach, S K Singh, and H J Girschick (2006)
Ann Rheum Dis 65, 1351-1356
   Abstract »    Full Text »    PDF »
Analysis of RAG expression by peripheral blood CD5+ and CD5- B cells of patients with childhood systemic lupus erythematosus.
H Morbach, S K Singh, C Faber, P E Lipsky, and H J Girschick (2006)
Ann Rheum Dis 65, 482-487
   Abstract »    Full Text »    PDF »
Expression of RAGs in Peripheral B Cells outside Germinal Centers Is Associated with the Expression of CD5.
S. Hillion, A. Saraux, P. Youinou, and C. Jamin (2005)
J. Immunol. 174, 5553-5561
   Abstract »    Full Text »    PDF »
Receptor editing in peripheral B cell tolerance.
J. S. Rice, J. Newman, C. Wang, D. J. Michael, and B. Diamond (2005)
PNAS 102, 1608-1613
   Abstract »    Full Text »    PDF »
Analysis of Marginal Zone B Cell Development in the Mouse with Limited B Cell Diversity: Role of the Antigen Receptor Signals in the Recruitment of B Cells to the Marginal Zone.
N. Kanayama, M. Cascalho, and H. Ohmori (2005)
J. Immunol. 174, 1438-1445
   Abstract »    Full Text »    PDF »
Inflammation Controls B Lymphopoiesis by Regulating Chemokine CXCL12 Expression.
Y. Ueda, K. Yang, S. J. Foster, M. Kondo, and G. Kelsoe (2004)
J. Exp. Med. 199, 47-58
   Abstract »    Full Text »    PDF »
T Cell Receptor Revision Does Not Solely Target Recent Thymic Emigrants.
C. J. Cooper, M. T. Orr, C. J. McMahan, and P. J. Fink (2003)
J. Immunol. 171, 226-233
   Abstract »    Full Text »    PDF »
P2Y-like receptor, GPR105 (P2Y14), identifies and mediates chemotaxis of bone-marrowhematopoietic stem cells.
B.-C. Lee, T. Cheng, G. B. Adams, E. C. Attar, N. Miura, S. B. Lee, Y. Saito, I. Olszak, D. Dombkowski, D. P. Olson, et al. (2003)
Genes & Dev. 17, 1592-1604
   Abstract »    Full Text »    PDF »
Expression of recombination-activating gene in mature peripheral T cells in Peyer's patch.
E. Kondo, H. Wakao, H. Koseki, T. Takemori, S. Kojo, M. Harada, M. Takahashi, S. Sakata, C. Shimizu, T. Ito, et al. (2003)
Int. Immunol. 15, 393-402
   Abstract »    Full Text »    PDF »
RAG-dependent peripheral T cell receptor diversification in CD8+ T lymphocytes.
P. Serra, A. Amrani, B. Han, J. Yamanouchi, S. J. Thiessen, and P. Santamaria (2002)
PNAS 99, 15566-15571
   Abstract »    Full Text »    PDF »
Chronic Graft-Versus-Host in Ig Knockin Transgenic Mice Abrogates B Cell Tolerance in Anti-Double-Stranded DNA B Cells.
D. R. Sekiguchi, S. M. Jainandunsing, M. L. Fields, M. A. Maldonado, M. P. Madaio, J. Erikson, M. Weigert, and R. A. Eisenberg (2002)
J. Immunol. 168, 4142-4153
   Abstract »    Full Text »    PDF »
Differential surrogate light chain expression governs B-cell differentiation.
Y.-H. Wang, R. P. Stephan, A. Scheffold, D. Kunkel, H. Karasuyama, A. Radbruch, and M. D. Cooper (2002)
Blood 99, 2459-2467
   Abstract »    Full Text »    PDF »
Expression of the recombination-activating genes in extrafollicular lymphocytes but no apparent reinduction in germinal center reactions in human tonsils.
N. Meru, A. Jung, I. Baumann, and G. Niedobitek (2002)
Blood 99, 531-537
   Abstract »    Full Text »    PDF »
Thyroid Autoimmune Disease : Demonstration of Thyroid Antigen-Specific B Cells and Recombination-Activating Gene Expression in Chemokine-Containing Active Intrathyroidal Germinal Centers.
M. P. Armengol, M. Juan, A. Lucas-Martin, M. T. Fernandez-Figueras, D. Jaraquemada, T. Gallart, and R. Pujol-Borrell (2001)
Am. J. Pathol. 159, 861-873
   Abstract »    Full Text »    PDF »
Localization of recombination activating gene 1/green fluorescent protein (RAG1/GFP) expression in secondary lymphoid organs after immunization with T-dependent antigens in rag1/gfp knockin mice.
H. Igarashi, N. Kuwata, K. Kiyota, K. Sumita, T. Suda, S. Ono, S. R. Bauer, and N. Sakaguchi (2001)
Blood 97, 2680-2687
   Abstract »    Full Text »    PDF »
Novel Secondary Ig VH Gene Rearrangement and In-Frame Ig Heavy Chain Complementarity-Determining Region III Insertion/Deletion Variants in De Novo Follicular Lymphoma.
C. B. Kobrin, M. Bendandi, and L. W. Kwak (2001)
J. Immunol. 166, 2235-2243
   Abstract »    Full Text »    PDF »
The Long Isoform of Terminal Deoxynucleotidyl Transferase Enters the Nucleus and, Rather than Catalyzing Nontemplated Nucleotide Addition, Modulates the Catalytic Activity of the Short Isoform.
C. L. Benedict, S. Gilfillan, and J. F. Kearney (2001)
J. Exp. Med. 193, 89-100
   Abstract »    Full Text »    PDF »
RAG1 and RAG2 Expression by B Cell Subsets from Human Tonsil and Peripheral Blood.
H. J. Girschick, A. C. Grammer, T. Nanki, M. Mayo, and P. E. Lipsky (2001)
J. Immunol. 166, 377-386
   Abstract »    Full Text »    PDF »
c-Myb Binds to a Sequence in the Proximal Region of the RAG-2 Promoter and Is Essential for Promoter Activity in T-Lineage Cells.
Q.-F. Wang, J. Lauring, and M. S. Schlissel (2000)
Mol. Cell. Biol. 20, 9203-9211
   Abstract »    Full Text »
Receptor Revision in Peripheral T Cells Creates a Diverse V{beta} Repertoire.
C. J. McMahan and P. J. Fink (2000)
J. Immunol. 165, 6902-6907
   Abstract »    Full Text »    PDF »
Antigen-independent Appearance of Recombination Activating Gene (RAG)-positive Bone Marrow B Cells in the Spleens of Immunized Mice.
F. Gartner, F. W. Alt, R. J. Monroe, and K. J. Seidl (2000)
J. Exp. Med. 192, 1745-1754
   Abstract »    Full Text »    PDF »
Molecular Biology of Burkitt's Lymphoma.
J. L. Hecht and J. C. Aster (2000)
J. Clin. Oncol. 18, 3707-3721
   Abstract »    Full Text »    PDF »
Heavy Chain Revision in MRL Mice: A Potential Mechanism for the Development of Autoreactive B Cell Precursors.
K. D. Klonowski and M. Monestier (2000)
J. Immunol. 165, 4487-4493
   Abstract »    Full Text »    PDF »
Secondary V(D)J Rearrangements and B Cell Receptor-Mediated Down-Regulation of Recombination Activating Gene-2 Expression in a Murine B Cell Line.
J. Maes, Y. Caspi, F. Rougeon, J. Haimovich, and M. Goodhardt (2000)
J. Immunol. 165, 703-709
   Abstract »    Full Text »    PDF »
Immunization and Infection Change the Number of Recombination Activating Gene (RAG)-expressing B Cells in the Periphery by Altering Immature Lymphocyte Production.
H. Nagaoka, G. Gonzalez-Aseguinolaza, M. Tsuji, and M. C. Nussenzweig (2000)
J. Exp. Med. 191, 2113-2120
   Abstract »    Full Text »    PDF »
Follicular lymphomas' BCL-2/IgH junctions contain templated nucleotide insertions: novel insights into the mechanism of t(14;18) translocation.
U. Jager, S. Bocskor, T. Le, G. Mitterbauer, I. Bolz, A. Chott, M. Kneba, C. Mannhalter, and B. Nadel (2000)
Blood 95, 3520-3529
   Abstract »    Full Text »    PDF »
Revising B Cell Receptors.
D. Nemazee and M. Weigert (2000)
J. Exp. Med. 191, 1813-1818
   Abstract »    Full Text »    PDF »
Receptor Revision of Immunoglobulin Heavy Chain Variable Region Genes in Normal Human B Lymphocytes.
P. C. Wilson, K. Wilson, Y.-J. Liu, J. Banchereau, V. Pascual, and J. D. Capra (2000)
J. Exp. Med. 191, 1881-1894
   Abstract »    Full Text »    PDF »
Cutting Edge: Recombinase-Activating Gene Expression and V(D)J Recombination in CD4+CD3low Mature T Lymphocytes.
E. Lantelme, B. Palermo, L. Granziero, S. Mantovani, R. Campanelli, V. Monafo, A. Lanzavecchia, and C. Giachino (2000)
J. Immunol. 164, 3455-3459
   Abstract »    Full Text »    PDF »
A novel nuclear phosphoprotein, GANP, is up-regulated in centrocytes of the germinal center and associated with MCM3, a protein essential for DNA replication.
K. Kuwahara, M. Yoshida, E. Kondo, A. Sakata, Y. Watanabe, E. Abe, Y. Kouno, S. Tomiyasu, S. Fujimura, T. Tokuhisa, et al. (2000)
Blood 95, 2321-2328
   Abstract »    Full Text »    PDF »
Cutting Edge: Absence of Expression of RAG1 in Peritoneal B-1 Cells Detected by Knocking into RAG1 Locus with Green Fluorescent Protein Gene.
N. Kuwata, H. Igarashi, T. Ohmura, S. Aizawa, and N. Sakaguchi (1999)
J. Immunol. 163, 6355-6359
   Abstract »    Full Text »    PDF »
Regulated Genomic Instability and Neoplasia in the Lymphoid Lineage.
G. J. Vanasse, P. Concannon, and D. M. Willerford (1999)
Blood 94, 3997-4010
   Full Text »    PDF »
Restricted Immunoglobulin Variable Region (Ig V) Gene Expression Accompanies Secondary Rearrangements of Light Chain Ig V Genes in Mouse Plasmacytomas.
L. Diaw, D. Siwarski, A. Coleman, J. Kim, G. M. Jones, G. Dighiero, and K. Huppi (1999)
J. Exp. Med. 190, 1405-1416
   Abstract »    Full Text »    PDF »
B Lymphocyte Selection and Age-Related Changes in VH Gene Usage in Mutant Alicia Rabbits.
X. Zhu, A. Boonthum, S.-K. Zhai, and K. L. Knight (1999)
J. Immunol. 163, 3313-3320
   Abstract »    Full Text »    PDF »
Somatic Mutation and Light Chain Rearrangement Generate Autoimmunity in Anti–single-stranded DNA Transgenic MRL/lpr Mice.
F. Brard, M. Shannon, E. L. Prak, S. Litwin, and M. Weigert (1999)
J. Exp. Med. 190, 691-704
   Abstract »    Full Text »    PDF »
Relaxed Negative Selection in Germinal Centers and Impaired Affinity Maturation in bcl-xL Transgenic Mice.
Y. Takahashi, D. M. Cerasoli, J. M. Dal Porto, M. Shimoda, R. Freund, W. Fang, D. G. Telander, E.-N. Malvey, D. L. Mueller, T. W. Behrens, et al. (1999)
J. Exp. Med. 190, 399-410
   Abstract »    Full Text »    PDF »
Antigen-Induced Somatic Diversification of Rabbit IgH Genes: Gene Conversion and Point Mutation.
C. R. Winstead, S.-K. Zhai, P. Sethupathi, and K. L. Knight (1999)
J. Immunol. 162, 6602-6612
   Abstract »    Full Text »    PDF »
Distinct Factors Regulate the Murine RAG-2 Promoter in B- and T-Cell Lines.
J. Lauring and M. S. Schlissel (1999)
Mol. Cell. Biol. 19, 2601-2612
   Abstract »    Full Text »    PDF »
Gene Conversion and Hypermutation During Diversification of VH Sequences in Developing Splenic Germinal Centers of Immunized Rabbits.
E. Schiaffella, D. Sehgal, A. O. Anderson, and R. G. Mage (1999)
J. Immunol. 162, 3984-3995
   Abstract »    Full Text »    PDF »
Activated Ras Signals Developmental Progression of Recombinase-activating Gene (RAG)-deficient Pro-B Lymphocytes.
A. C. Shaw, W. Swat, R. Ferrini, L. Davidson, and F. W. Alt (1999)
J. Exp. Med. 189, 123-129
   Abstract »    Full Text »    PDF »
RAG Expression in B Cells in Secondary Lymphoid Tissues.
W. YU, H. NAGAOKA, Z. MISULOVIN, E. MEFFRE, H. SUH, M. JANKOVIC, N. YANNOUTSOS, R. CASELLAS, E. BESMER, F. PAPAVASILIOU, et al. (1999)
Cold Spring Harb Symp Quant Biol 64, 207-210
   Abstract »    PDF »
Interleukin 7 Receptor Control of  T Cell Receptor gamma  Gene Rearrangement: Role of Receptor-associated Chains and Locus Accessibility.
S. K. Durum, S. Candeias, H. Nakajima, W. J. Leonard, A. M. Baird, L. J. Berg, and K. Muegge (1998)
J. Exp. Med. 188, 2233-2241
   Abstract »    Full Text »    PDF »
Analyses of Single B Cells by Polymerase Chain Reaction Reveal Rearranged VH with Germline Sequences in Spleens of Immunized Adult Rabbits: Implications for B Cell Repertoire Maintenance and Renewal.
D. Sehgal, E. Schiaffella, A. O. Anderson, and R. G. Mage (1998)
J. Immunol. 161, 5347-5356
   Abstract »    Full Text »    PDF »
Rapid elimination of mature autoreactive B cells demonstrated by Cre-induced change in B cell antigen receptor specificity in vivo.
K.-P. Lam and K. Rajewsky (1998)
PNAS 95, 13171-13175
   Abstract »    Full Text »    PDF »
Antigen Receptor Engagement Turns off the V(D)J Recombination Machinery in Human Tonsil B Cells.
E. Meffre, F. Papavasiliou, P. Cohen, O. de Bouteiller, D. Bell, H. Karasuyama, C. Schiff, J. Banchereau, Y.-J. Liu, and M. C. Nussenzweig (1998)
J. Exp. Med. 188, 765-772
   Abstract »    Full Text »    PDF »
Surrogate Light Chain Production During B Cell Differentiation: Differential Intracellular Versus Cell Surface Expression.
Y.-H. Wang, J. Nomura, O. M. Faye-Petersen, and M. D. Cooper (1998)
J. Immunol. 161, 1132-1139
   Abstract »    Full Text »    PDF »
Expression of Recombination Activating Genes in Germinal Center B Cells: Involvement of Interleukin 7 (IL-7) and the IL-7 Receptor.
M. Hikida, Y. Nakayama, Y. Yamashita, Y. Kumazawa, S.-I. Nishikawa, and H. Ohmori (1998)
J. Exp. Med. 188, 365-372
   Abstract »    Full Text »    PDF »
Restricted Expression of E2A Protein in Primary Human Tissues Correlates with Proliferation and Differentiation.
M. N. Rutherford and D. P. LeBrun (1998)
Am. J. Pathol. 153, 165-173
   Abstract »    Full Text »    PDF »
Ku70 Is Required for Late B Cell Development and Immunoglobulin Heavy Chain Class Switching.
J. P. Manis, Y. Gu, R. Lansford, E. Sonoda, R. Ferrini, L. Davidson, K. Rajewsky, and F. W. Alt (1998)
J. Exp. Med. 187, 2081-2089
   Abstract »    Full Text »    PDF »
In Situ Studies of the Primary Immune Response to (4-Hydroxy-3-Nitrophenyl)Acetyl. V. Affinity Maturation Develops in Two Stages of Clonal Selection.
Y. Takahashi, P. R. Dutta, D. M. Cerasoli, and G. Kelsoe (1998)
J. Exp. Med. 187, 885-895
   Abstract »    Full Text »    PDF »
Frequent occurrence of deletions and duplications during somatic hypermutation: Implications for oncogene translocations and heavy chain disease.
T. Goossens, U. Klein, and R. Kuppers (1998)
PNAS 95, 2463-2468
   Abstract »    Full Text »    PDF »
Rearrangement of lambda  Light Chain Genes in Mature B Cells In Vitro and In Vivo. Function of Reexpressed Recombination-activating Gene (RAG) Products.
M. Hikida and H. Ohmori (1998)
J. Exp. Med. 187, 795-799
   Abstract »    Full Text »    PDF »
FLT-3 Ligand and Marrow Stroma-Derived Factors Promote CD3gamma , CD3delta , CD3zeta , and RAG-2 Gene Expression in Primary Human CD34+LIN-DR- Marrow Progenitors.
P. M. Gaffney, J. Lund, and J. S. Miller (1998)
Blood 91, 1662-1670
   Abstract »    Full Text »    PDF »
V(D)J Recombination in Mature B Cells: A Mechanism for Altering Antibody Responses.
F. Papavasiliou, R. Casellas, H. Suh, X. Qin, E. Besmer, R. Pelanda, D. Nemazee, K. Rajewsky, and M. C. Nussenzweig (1997)
Science 278, 298-301
   Abstract »    Full Text »
Disruption of the Bcl6 Gene Results in an Impaired Germinal Center Formation.
T. Fukuda, T. Yoshida, S. Okada, M. Hatano, T. Miki, K. Ishibashi, S. Okabe, H. Koseki, S. Hirosawa, M. Taniguchi, et al. (1997)
J. Exp. Med. 186, 439-448
   Abstract »    Full Text »    PDF »


To Advertise     Find Products

ADVERTISEMENT

Featured Jobs

Science. ISSN 0036-8075 (print), 1095-9203 (online)