Thomas Graf (born 28 September 1944) is a

biologist A biologist is a scientist who conducts research in biology. Biologists are interested in studying life on Earth, whether it is an individual Cell (biology), cell, a multicellular organism, or a Community (ecology), community of Biological inter ...

at the

Centre for Genomic Regulation The Centre for Genomic Regulation (CRG, ''Centre de Regulació Genòmica'' in Catalan) is a biomedical and genomics research centre based in Barcelona. Most of its facilities and laboratories are located in the Barcelona Biomedical Research Par ...

(CRG) in Barcelona, Spain. He is a pioneer in cell reprogramming, showing that blood cells can be transdifferentiated by

transcription factor In molecular biology, a transcription factor (TF) (or sequence-specific DNA-binding factor) is a protein that controls the rate of transcription (genetics), transcription of genetics, genetic information from DNA to messenger RNA, by binding t ...

s. He is also known for his early work on

oncogene An oncogene is a gene that has the potential to cause cancer. In tumor cells, these genes are often mutated, or expressed at high levels.

s carried by

retrovirus A retrovirus is a type of virus that inserts a DNA copy of its RNA genome into the DNA of a host cell that it invades, thus changing the genome of that cell. After invading a host cell's cytoplasm, the virus uses its own reverse transcriptase e ...

es and oncogene cooperation in

leukemia Leukemia ( also spelled leukaemia; pronounced ) is a group of blood cancers that usually begin in the bone marrow and produce high numbers of abnormal blood cells. These blood cells are not fully developed and are called ''blasts'' or '' ...

formation.

Research

In the late 70s Graf co-discovered several cell-derived oncogenes acquired by avian

es, designated ''Mac'' (later changed into ''Myc''), ''Erb'' and ''Myb''. He found that several naturally occurring virus strains have acquired various pairwise combinations of oncogenes and that these cooperate to cause acute leukemia, an early example for the multigenic origin of cancers. He also showed that the transcription factor ''Myb'' can reversibly block the differentiation of

white blood cell White blood cells (scientific name leukocytes), also called immune cells or immunocytes, are cells of the immune system that are involved in protecting the body against both infectious disease and foreign entities. White blood cells are genera ...

s, one of the first demonstrations of induced cell fate changes. In his more recent research he showed that different types of specialized blood cells can be induced to convert into each other by forced

expression. In 1995 he pioneered this technique permitting the transdifferentiation of white blood cells into red blood cell precursors and vice versa induced by Gata1 and PU.1, respectively. Later (2004) he managed to convert B lymphocytes into functional macrophages, using C/EBPa as a driver. Using the same approach he was also first to induce a conversion of more distantly related cells, namely that of non-blood cells into

macrophage Macrophages (; abbreviated MPhi, φ, MΦ or MP) are a type of white blood cell of the innate immune system that engulf and digest pathogens, such as cancer cells, microbes, cellular debris and foreign substances, which do not have proteins that ...

s. Finally, he found that forced C/EBPa expression in malignant lymphocyte precursors leads to the formation of macrophages and loss of tumorigenicity, suggesting transdifferentiation as an alternative avenue for therapeutic interventions.

Awards

* 1983 Wilhelm-Warner-Foundation Award * 1983 Main Award, German Society for Microbiology and Hygiene * 1983 Kind-Philipp-Foundation Leukemia Research Award * 1988 Josef-Steiner-Foundation Prize * 1988 Theodor Boveri Lecture and Award * 1989 Paul Ehrlich-Ludwig Darmstaedter Prize

References

External links

Thomas Graf laboratory
at the

.
Profile at EuroStemCell
* News article
Nobel Prize-winning ‘iPSC’ Stem Cell Method Vastly Improved
at Bioscience Technology {{DEFAULTSORT:Graf, Thomas 20th-century German biologists Living people 1944 births 21st-century German biologists Scientists from Vienna