# Notch2 Amplification of B Cell Division and Differentiation Fates > **NIH NIH F31** · UNIVERSITY OF PENNSYLVANIA · 2024 · $36,662 ## Abstract Project Summary The cellular and molecular mechanisms controlling cell cycle entry and plasma cell differentiation remain poorly understood. One key facet to this problem is how naïve B cells achieve a state of readiness for the plasma cell (PC) fate. This project strives to understand the molecular mechanisms whereby activation of the Notch pathway in naïve B cells fosters biochemical events that accelerate both mitosis and PC differentiation. Further, this project addresses whether these processes will amplify B cell responses to SARS-CoV-2 immunogens. One major hurdle to vaccine development for complex pathogens are facilitating diverse and durable antibody responses that can keep up with rapid mutations and stand the test of time. As such, understanding the mechanisms that underlie optimal B cell responses are vital to improve vaccine design. One distinctive B cell subset, marginal zone (MZ) B cells, exhibit a selective advantage at generating effector responses. Residing in the marginal sinus of the spleen at the interface between incoming blood supply and lymphoid follicles, this innate-like subset responds to blood-borne antigens, serving as a first line of defense to generate antibody- secreting PCs in a matter of hours. Unlike conventional follicular (FO) B cells, MZ B cells have a distinctive requirement for the signal Notch2, an evolutionarily conserved transmembrane receptor family member that dictates cell fate decisions. Notch2 is known to drive lineage commitment of the MZ B cell pool during development, but how this signal is used continuously to maintain mature MZ B cells is poorly understood. As such, it is reasonable to speculate that Notch2 signaling instructs a constitutively poised state in resting B cells by modifying activation requirements and differentiative events. Indeed, preliminary data demonstrate the induction of Notch2 signaling in non-poised FO B cells enhances their responsiveness to antigen receptor or TLR signals to promote their proliferation and differentiation into PCs. The central hypothesis of this proposal is that Notch2 independently augments PC differentiation and cell division, both features which hold potential to amplify vaccine responses. Herein, this proposal will independently interrogate the mechanism(s) by which Notch2 modifies proliferative and differentiative potentials in aim 1, and the potential for Notch2 signals to improve SARS-CoV-2 vaccine responses in aim 2. The significance of investigating how Notch2 regulates B cell responses is twofold. For one, this proposal will challenge the current understanding of Notch2 as a determinant of cell fate decisions, elucidating how this signal is tied to activation and effector programs. Additionally, this proposal can better inform vaccination strategies using Notch2 signaling as a tool to enhance the frequency and diversity of a given antibody response. ## Key facts - **NIH application ID:** 10900500 - **Project number:** 1F31AI179166-01A1 - **Recipient organization:** UNIVERSITY OF PENNSYLVANIA - **Principal Investigator:** Jennifer Londregan - **Activity code:** F31 (R01, R21, SBIR, etc.) - **Funding institute:** NIH - **Fiscal year:** 2024 - **Award amount:** $36,662 - **Award type:** 1 - **Project period:** 2024-08-01 → 2026-07-31 ## Primary source NIH RePORTER: https://reporter.nih.gov/project-details/10900500 ## Citation > US National Institutes of Health, RePORTER application 10900500, Notch2 Amplification of B Cell Division and Differentiation Fates (1F31AI179166-01A1). Retrieved via AI Analytics 2026-05-27 from https://api.ai-analytics.org/grant/nih/10900500. Licensed CC0. --- *[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*