Johan Jansson’s research shows that leukemia cells that have been exposed to chemotherapy and survived did not develop resistance against bone marrow transplants from a sibling, for example. At the same time, however, several important changes were observed in these cancer cells. On the one hand, they were less vulnerable to chemotherapy and, on the other, their growth rate increased.
Johan Jansson also identified several immunologically important genes that either increased or decreased when they had been exposed to a bone marrow transplant. Three of these genes were especially interesting in that they were involved in activating the immune defense and the killing of cancer cells. It was also shown that such a bone marrow transplant could have an inhibiting effect on the leukemia cells that also proved to be able to activate parts of the immune defense.
Finally, Johan Jansson studied whether it is possible to check the leukemia cells that remain after a bone marrow transplant. This was done by vaccinating mice with a mixture of ‘dead’ leukemia cells and immune cells from a donor. It was observed that the immune defense was activated to some degree, but that the mice did not live any longer as a result. On the other hand, it was seen that these mice had B cells that produced antibodies against leukemia cells. This knowledge could be further elaborated to develop and enhance the effects of a bone marrow transplant.
Johan Jansson publicly defended his dissertation Acute Lymphoblastic Leukemia in the Allogenic Environment on September 29.
Thesis directors: Prof. Craig A. Mullen, University of Rochester, NY, USA; Prof. Sven Tågerud, Kalmar University, Sweden.
Deputy director: Prof. Kristina Nilsson Ekdahl, Kalmar University.
External examiner: Prof. Mikael Sigvardsson, Linköping University, Sweden