Navigation Links
Between B cells and T cells
Date:7/23/2013

Mature cells develop through a number of immature stages. During this process, they must remember the specialization they are committed to. For immune system B cells, Rudolf Grosschedl of the Max Planck Institute of Immunobiology and Epigenetics and his team have discovered that the transcription factor EBF1 is crucial for B cells to remember who they are. When the researchers switched off the transcription factor, the cells lost their previous identity and developed into T cells. Unlike most other cell types, B cells have a characteristic footprint in their genetic makeup and this allowed the researchers to identify the origin of each individual cell.

During the transition from stem cells to becoming a functional part of the immune system, cells must undergo a number of specialization stages where they have the opportunity to decide between pathways leading to the various cell types found in the blood. It is also important that once they have chosen a specialization, they remain committed to it.

Immune system B and T cells come from the same stem cell. Rudolf Grosschedl and his colleagues were able to prove as early as 1995 that the transcription factor EBF1 is active only in some of these cells and this induces their development into B cells. Until now, however, it was unclear whether EBF1 also played a part in constantly reminding the B cells of their identity.

B cells usually die when EBF1 is switched off. In collaboration with researchers from the University of Freiburg, the Max Planck researchers collected mouse B cells at a late stage of their development and transferred them to mice lacking an immune system. They then switched off the EBF1 gene in the transplanted B cells. After three months, they checked whether immune cells were still present in the mice. "We thought that the chance of this transfer enabling the cells to remain alive was slim, so we were very pleased that it worked," says Robert Nechanitzky, a doctoral student and first author of the study. The researchers did indeed find immune cells, but the B cells had forgotten their previous identity. In their place were T cells and natural killer cells, which normally would not be found in these animals.

To find out whether the T and natural killer cells actually had come from the transplanted B cells, the researchers looked for the specific genetic footprint of B cells. Unlike most other cells in the body, B cells change their DNA sequence during their development. To produce antibodies, they bring together several gene segments by cutting and joining their DNA to create a sequence able to code for a functional antibody. The researchers found precisely this typical genetic footprint of B cells in both T cells and natural killer cells. They concluded that after the transcription factor EBF1 had been switched off, the transplanted B cells had forgotten their specialization and had turned into alternate cell types. Until now, it was only known that the absence of the transcription factor Pax5 had such an effect. "We believe that the two proteins regulate different aspects of cell type specification. EBF1 primarily represses genes that would initiate an alternative program of development in the B cells, while Pax5 ensures that they no longer react to signals that would enable them to select a different specialization," says Grosschedl.

The Freiburg-based researchers now want to understand the exact molecular interactions in the cells and better define the network of factors involved. In the long term, they hope this knowledge will allow cells to be reprogrammed, for example in the case of a pathological loss of a cell type.


'/>"/>

Contact: Dr. Rudolf Grosschedl
grosschedl@immunbio.mpg.de
49-761-510-8711
Max-Planck-Gesellschaft
Source:Eurekalert

Related biology news :

1. UC Santa Barbara researchers discover genetic link between visual pathways of hydras and humans
2. Drawing connections between food webs
3. Geographic information systems demonstrate links between health and location
4. Biosignatures distinguish between tuberculosis and sarcoidosis
5. IU role in Human Microbiome Project exposes battle history between bacteria, viruses in human body
6. Link between vitamin C and twins can increase seed production in crops
7. Study provides first evidence of coevolution between invasive, native species
8. How sweet it is: Tomato researchers discover link between ripening, color and taste
9. Highlighting molecular clues to the link between childhood maltreatment and later suicide
10. Differences between human twins at birth highlight importance of intrauterine environment
11. Caltech researchers find evidence of link between immune irregularities and autism
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:4/28/2016)... -- First quarter 2016:   , Revenues ... first quarter of 2015 The gross margin was 49% ... and the operating margin was 40% (-13) Earnings per ... from operations was SEK 249.9 M (21.2) , Outlook ... 7,000-8,500 M. The operating margin for 2016 is estimated ...
(Date:4/15/2016)...  A new partnership announced today will help ... in a fraction of the time it takes ... life insurance policies to consumers without requiring inconvenient ... Diagnostics, rapid testing (A1C, Cotinine and HIV) and ... weight, pulse, BMI, and activity data) available at ...
(Date:3/31/2016)... 2016   LegacyXChange, ... "Company") LegacyXChange is excited to release its ... to be launched online site for trading 100% guaranteed ... will also provide potential shareholders a sense of the ... an industry that is notorious for fraud. The video ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... ... 2016 , ... Supplyframe, the Industry Network for electronics hardware ... . Located in Pasadena, Calif., the Design Lab’s mission is to bring together ... built and brought to market. , The Design Lab is Supplyframe’s physical representation ...
(Date:6/23/2016)... 23, 2016  Blueprint Bio, a company dedicated to ... medical community, has closed its Series A funding round, ... "We have received a commitment from Forentis ... need to meet our current goals," stated Matthew ... runway to complete validation on the current projects in ...
(Date:6/23/2016)... WI (PRWEB) , ... June 23, 2016 , ... ... focused on quality, regulatory and technical consulting, provides a free webinar ... presented on July 13, 2016 at 12pm CT at no charge. , Incomplete ...
(Date:6/22/2016)... SAN DIEGO , June 22, 2016 /PRNewswire/ ... partnership that will allow them to produce up ... (HiPSC) from one lot within one week. These ... their time laboriously preparing cells and spend more ... made possible through a proprietary, high-volume manufacturing process ...
Breaking Biology Technology: