Two types of B cells with different functions
A known population of B cells that makes antibodies effective against a wide range of pathogens resides in the spleen, an organ responsible for filtering bacteria and other harmful particles from the blood. Two types of B cells are formed in the spleen: MZB cells, named so because they are found in an area of the organ called the ‘marginal zone’, and follicular B cells. However, scientists knew little about the mechanisms governing why early B cells develop into MZB cells versus follicular B cells.
Hamida Hammad (VIB-UGent): “We had a ‘eureka!’ moment after discovering that a little-known protein, Taok3, brings a certain proteinase, ADAM10, to the surface of the immature B cell that triggers its development into an MBZ cell. Without that special event, immature B cells can only develop into follicular B cells.”
Taok3’s role in triggering B cell differentiation
In mouse strains, the team observed in vivo that without Taok3, immature B cells never ‘committed’ to becoming MZB cells. MZB cells generate antibodies against encapsulated bacteria such as pneumococcus when they enter the bloodstream.
Hamida Hammad (VIB-UGent): “With an abundance of only follicular B cells, Taok3-free mice are less capable of fighting these types of bacteria effectively.”
Potential therapies for protein-related disease
Collaboration with other Belgian scientists revealed that proteins similar to ADAM10 were also affected in animals without Taok3, potentially contributing to the development of brain diseases characterized by too much ADAM10 activity, such as the genetic disorder fragile X syndrome, which can result in intellectual disability.
Bart Lambrecht (VIB-UGent/UZ Gent): “Even more, we also found connections between Taok3 and the development of diabetes and asthma. This research has generated insights that are very relevant to new therapies to a range of important diseases. It goes to show that basic science sometimes leads to unexpected – and important – applications.”
Questions from patients
A breakthrough in research is not the same as a breakthrough in medicine. The realizations of VIB researchers can form the basis of new therapies, but the development path still takes years. This can raise a lot of questions. That is why we ask you to please refer questions in your report or article to the email address that VIB makes available for this purpose: firstname.lastname@example.org. Everyone can submit questions concerning this and other medically-oriented research directly to VIB via this address.