Mihai Azoitei, Ph.D.
Associate Professor of Cell Biology
Member of the Duke Human Vaccine Institute
E-mail: mihai.azoitei@duke.edu
2 Genome Court
MSRBII Bldg. Room 3015
DUMC 103020
Durham, NC 27710
Telephone: (919) 681-8543
B cell Intracellular Signaling and Vaccine Design
Research in our group is focused on two synergistic areas that are critical for the development of broadly protective vaccines against highly infectious pathogens. First, we aim to understand the intracellular signaling pathways that control B cell activation upon antigen encounter. We then combine these findings with insights from immunology, virology, and structural biology, to develop next-generation vaccines.
To study B cell intracellular signaling in response to antigens, we engineer and utilize molecular tools (fluorescent biosensors and optogenetic probes) to visualize and control the activity of key signaling molecules in live cell microscopy experiments. Upon engagement of B cell receptors by antigens, multiple signaling pathways are triggered, and their activation levels and coordination in space and time are critical for B cell function. Our current focus is on mapping the activity of Rho GTPases and their main activators, the Dbl family of Guanine Exchange Factors (GEFs). These molecules control B cell morphodynamics and are critical for the formation of the immunological synapse. Because of their transient and dynamic nature, we aim to study GEF/GTPase signaling networks in living cells and to map their activity at the subcellular level and with sub-second kinetics.
For vaccine design, we employ a rational, structure-based approach that utilizes state-of-the-art computational protein design algorithms and high-throughput library screening. These techniques allow us to model the atomic details of protein structures and protein-protein interactions with high confidence and provide us with an experimental platform to rapidly screen millions of immunogen candidates. We are currently developing immunogens against HIV, coronaviruses, and influenza. The immunogens we engineer are characterized through collaborations with structural biologists, immunologists and virologists.
Recent Publications
1. Kapingidza B, Marston DJ, Harris C, Wrapp D, Winters K, Rhodes B, [..], Saunders KO, Haynes BF, Azoitei ML. Engineered immunogens to elicit antibodies against conserved coronavirus epitopes. Nature Communications, 2023; 14: 7897. PMID: 38036525; PMCID: PMC10689493.
2. Swanson O, Beam JS, Rhodes B, Wang A, Barr M, Chen H, Parks R, Saunders KO, Haynes BF, Wiehe K, Azoitei ML. Identification of CDRH3 loops in the B cell receptor repertoire that can be engaged by candidate immunogens. PLOS Pathogens. 19(5): e1011401, 2023. PMID: 37196027
3. Li D, Brackenridge S, Walters LC, Swanson O, Harlos K, Rozbesky D, Cain DW, Wiehe K, Scearce RM, Barr M, Mu Z, Parks R, Quastel M, Edwards J, Wang Y, Rountree W, Saunders KO, Ferrari G, Borrow P, Jones EY, Alam SM, Azoitei ML*, Gillespie GM*, McMichael AJ*, Haynes BF*. Mouse and Human Antibodies that Bind HLA-E-Leader Peptide Complexes and Enhance NK Cell Cytotoxicity. Communications Biology, 5, 271 (2022).
4. Swanson O, Rhodes B, Wang A, Shi-Mao X, Cooper M, Parks R, Sanzone A, Louder MK, Lin BC, Doria-Rose NA, Saunders KO, Bonsignori M, Wiehe K, Haynes BF, Azoitei ML. Rapid selection of HIV envelopes that bind to neutralizing antibody B cell lineage members with functional improbable mutations. Cell Reports. 36(7):109561, 2021. PMID: 34407396
5. Azoitei ML, Noh J, Marston DJ, Roudot P, Marshall CB, Daugird TA, Lisanza SL, Sandí MJ, Ikura M, Sondek J, Rottapel R, Hahn KM, Danuser G. Spatiotemporal dynamics of GEF-H1 activation controlled by microtubule- and Src-mediated pathways. J Cell Biol. 2019 Sep 2;218(9):3077-3097. doi: 10.1083/jcb.201812073. Epub 2019 Aug 16. PMID: 31420453; PMCID: PMC6719461.