Navigation Links
Between B cells and T cells

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

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:
(Date:11/19/2015)... YORK , Nov. 19, 2015  Although some ... market is dominated by a few companies, according to ... companies own 51% of the market share of the ... The World Market for Molecular Diagnostic s ... "The market is still controlled by one company ...
(Date:11/17/2015)...  Vigilant Solutions announces today that Mr. Dick ... --> --> Mr. ... partnership at TPG Capital, one of the largest global ... in revenue.  He founded and led TPG,s Operating Group, ... from 1997 to 2013.  In his first role, he ...
(Date:11/12/2015)... 2015   Growing need for low-cost, easy ... been paving the way for use of biochemical ... analytes in clinical, agricultural, environmental, food and defense ... in medical applications, however, their adoption is increasing ... continuous emphasis on improving product quality and growing ...
Breaking Biology News(10 mins):
(Date:11/28/2015)... ... November 28, 2015 , ... • Jeon Jin Bio ... porcine and rodent control solutions , Bird ... oil, works across all sensory modalities including visual, smell, taste and touch, enabling safe, ...
(Date:11/27/2015)... November 27, 2015 ... popularity of companion diagnostics is one of ... market with pharmaceutical companies and diagnostic manufacturers ... tests. . --> ... report on global cancer biomarkers market spread ...
(Date:11/25/2015)... 2015 --> ... - 2020 report analyzes that automating biobanking workflow ... in long-term samples, minimizing manual errors, improving the ... manual errors such as mislabeling or inaccurate sample ... plays a vital role in blood fractionation, DNA ...
(Date:11/25/2015)... , November 25, 2015 ... cat and human plaque and pave the way for more ... problems in cats     --> ... most commonly diagnosed health problems in cats, yet relatively little ... now. Two collaborative studies have been conducted by researchers from ...
Breaking Biology Technology: