IMMATURE SURFACE IG+ B-CELLS CAN CONTINUE TO REARRANGE KAPPA-L-CHAIN AND LAMBDA-L-CHAIN GENE LOCI

ROLINK, A; GRAWUNDER, U; HAASNER, D; Strasser, A; MELCHERS, F

Author(s): ROLINK, A; GRAWUNDER, U; HAASNER, D; Strasser, A; MELCHERS, F;
Details: Publication Year 1993-10-01,Volume 178,Issue #4,Page 1263-1270
Journal Title: JOURNAL OF EXPERIMENTAL MEDICINE
Publication Type: Journal Article
Abstract: Pro and pre B cells possess the long-term capacity to proliferate in vitro on stromal cells and interleukin 7 (IL-7) and can differentiate to surface immunoglobulin (sIg+) cells upon removal of IL-7 from the cultures. A key event in this differentiation is the extensive cell loss due to apoptosis. Because the proto-oncogene bcl-2 can promote cell survival, we established pre-B cell lines from Emu-bcl-2 transgenic mice. These pre-B cells have the same properties as those derived from non-bcl-2 transgenic mice except that they do not die by apoptosis. This allowed us to study the fate of newly formed B cells in vitro for a longer period of time. Here we show that early during the differentiation of pre-B cells, upregulation of RAG-1 and RAG-2 expression go hand in hand with rearrangements of the Ig gene loci. Moreover, the newly formed sIg+ B cells continue to express RAG-1 and RAG-2 and continue to rearrange L chain gene loci, even in the absence of proliferation, in an orderly fashion, so that kappaL+ sIg+ cells can become lambdaL+ sIg+ or sIg- cells, whereas lambdaL+ sIg+ cells can become sIg-, but not kappaL+ sIg+ cells. Thus, deposition of a complete Ig molecule on the surface of a B cell does not automatically stop the Ig-rearrangement machinery.
Publisher: ROCKEFELLER UNIV PRESS
Keywords: LIGHT-CHAIN; CHROMOSOMAL BREAKPOINT; FOLLICULAR LYMPHOMA; V(D)J RECOMBINATION; TRANSGENIC MICE; BCL-2 GENE; VK GENES; T-CELL; EXPRESSION; SURVIVAL
Publisher's Version: https://doi.org/10.1084/jem.178.4.1263
Terms of Use/Rights Notice: Refer to copyright notice on published article.

Creation Date: 1993-10-01 12:00:00