Dendritic cells play an important role in setting the course of our immune system. However, what determines their heterogeneity and functional specialization is still not sufficiently understood. An international collaboration consisting of researchers from the University Hospital Bonn (UKB), the University of Bonn and the Technical University of Denmark, among others, has investigated the role of the transcription factor Bcl6 in dendritic cells in a mouse model and discovered that a subgroup is highly dependent on this protein. The findings contribute to a better understanding of immunological processes during infections, vaccinations, allergies and autoimmunity. The results have now been published in the renowned scientific journal "Nature Communications".

Chemokines are signalling proteins that orchestrate the interaction of immune cells against pathogens and tumours. To understand this complex network, various techniques have been developed to identify chemokine-producing cells. However, it has not yet been possible to determine which cells react to these chemokines. Researchers at the University Hospital Bonn (UKB) and the University of Bonn have developed a new class of genetically modified mice that enables the simultaneous identification of chemokine producers and sensors. Using the chemokine Ccl3 as a “proof of principle”, they discovered that its function in the immune defence against viruses is different than had been previously assumed. Their results have now been published in the "Journal of Experimental Medicine".

Many kidney diseases are manifested by protein in the urine. However, until now it was not possible to determine whether the protein excretion is caused by only a few, but severely damaged, or by many moderately damaged of the millions of small kidney filters, known as glomeruli. Researchers at the University Hospital Bonn, in cooperation with mathematicians from the University of Bonn, have developed a new computer method to clarify this question experimentally. The results of their work have now been published as an article in press in the leading kidney research journal "Kidney International".

Cisplatin is used successfully in the chemotherapy of testicular cancer. However, patients who develop resistance to the cytostatic drug urgently need alternative therapy options. Researchers at the University Hospital Bonn (UKB) have now been able to elucidate a mechanism underlying cisplatin resistance in testicular cancer. Using CRISPR gene scissors, they identified the NAE1 gene as its driver. Inhibiting this resistance mediator by adding the NAE1 inhibitor MLN4924 not only restores the effect of cisplatin, but also has an additional killing effect on tumor cells. The study results have now been published in the British Journal of Cancer.

Hemophilia A is the most common severe form of hemophilia. It affects almost exclusively males. The disease can usually be treated well, but not for all sufferers. A study at the University of Bonn has now elucidated an important mechanism that is crucial for making the therapy effective. The results could help better tailor treatment to patients. They have already been published online in a preliminary version; the final version will soon be published in the "Journal of Clinical Investigation."

Our own immune system can become the enemy when mechanisms that are actually protective get out of control. In ANCA-associated vasculitis, excessive inflammatory reactions lead to pulmonary hemorrhages that can be fatal if left untreated. Researchers at the University of Bonn, together with colleagues from Germany, the Netherlands, Switzerland and England, have deciphered a mechanism in mice and patients that leads to the severe disease. The results are now published in the Journal of Experimental Medicine.

In severe Covid-19 patients, the metabolism produces insufficient amounts of certain energy-rich compounds called ketone bodies. However, these energy carriers are needed by two important cell types in the immune system in order to fight the virus effectively. Perhaps this finding explains why some people fall ill so much more severely than others. A study led by the University of Bonn and the University Hospital Bonn at least points in this direction. The results have now been published in the journal Nature. They also give hope for new therapies.

Researchers at the Universities of Bonn and Sao Paulo have succeeded in mitigating chronic inflammation in mice using customized "mini-antibodies." These nanobodies enabled them to dissolve molecular complexes in tissue that normally activate the immune system. The nanobodies produced may in future help to slow down unwanted inflammatory reactions that cause diseases such as arthritis or neurodegeneration. The study is published in the journal EMBO Molecular Medicine.