B Lymphocyte Biology
B lymphocytes are key players of the immune response, mostly through the generation of a hugely diverse repertoire of protective antibodies.
However, misregulation of B lymphocyte function is associated with multiple health conditions, including immune deficiencies, autoimmunity and cancer. Our lab is interested in various aspects of B cell biology, in particular the regulatory and diversification events that take place in germinal centers. Diversification in germinal centers entails the remodeling of immunoglobulin genes through two mechanisms called somatic hypermutation (SHM) and class switch recombination (CSR) that allow the generation of high-affinity, specialized antibodies. Both SHM and CSR are initiated by the very same enzyme, Activation Induced Deaminase (AID), whose activity can also promote unwanted lesions on the DNA, such as mutations and chromosome translocations. Our lab focuses on understanding AID function and microRNA-regulatory mechanisms in germinal centers. Some of our recent findings include:
- We showed that Dicer depletion in B cells promotes autoimmune disease, revealing a crucial role of microRNAs in the establishment of tolerance during late B cell differentiation
- We identified miR181b as a microRNA that negatively regulates AID expression, which indicates that this microRNA can have a tumor suppressor role in lymphoma development
- We have found that UNG, an enzyme normally involved in base excision repair, shapes the sequence specificity of AID-induced mutations
The B Cell Biology Lab welcomes enthusiastic and creative scientists to join the crew, contact us!