Exit from germinal center to become quiescent memory B cells depends on metabolic reprograming and provision of a survival signal

Compartments and Connections Within the Germinal Center

Protective high affinity antibody responses emerge through an orchestrated developmental process that occurs in germinal centers (GCs). While GCs have been appreciated since 1930, a wealth of recent progress provides new insights into the molecular and cellular dynamics governing humoral immunity. In this review, we highlight advances that demonstrate that fundamental GC B cell function, selection, proliferation and SHM occur within distinct cell states. The resulting new model provides new opportunities to understand the evolution of immunity in infectious, autoimmune and neoplastic diseases.

Anti-malarial humoral immunity: the long and short of it

Humoral immunity is critical for limiting Plasmodium parasite infections and the severity of malaria. Naturally acquired immunity against malaria occurs inefficiently and protection is relatively short-lived. Here we review recent advances and explore emerging hypotheses regarding the molecular and cellular pathways that regulate Plasmodium parasite-specific B cell responses and durable anti-malarial humoral immunity.

AMPK Metabolism in the B Lineage Modulates Humoral Responses

A large and growing body of evidence supports functions of enzymes that regulate or effect cellular metabolism in governing the development, survival, and effector functions of immune cells—especially T cells, macrophages, and dendritic cells. Among these proteins, adenosine monophosphate-activated protein kinase (AMPK) is a conserved ATP and nutrient sensor that regulates multiple metabolic pathways to promote energy homeostasis. Although AMPK had been shown to regulate aspects of CD4⁺ and CD8⁺ T cell biology, its function in B lymphocytes has been less clear. Here, we review recent advances in our understanding of the role of AMPK in the metabolism, function, and maintenance of the B lineage.

Transcriptional and Metabolic Control of Memory B Cells and Plasma Cells

For many infections and almost all vaccines, neutralizing-antibody-mediated immunity is the primary basis and best functional correlate of immunological protection. Durable long-term humoral immunity is mediated by antibodies secreted by plasma cells that preexist subsequent exposures and by memory B cells that rapidly respond to infections once they have occurred. In the midst of the current pandemic of coronavirus disease 2019, it is important to define our current understanding of the unique roles of memory B cells and plasma cells in immunity and the factors that control the formation and persistence of these cell types. This fundamental knowledge is the basis to interpret findings from natural infections and vaccines. Here, we review transcriptional and metabolic programs that promote and support B cell fates and functions, suggesting points at which these pathways do and do not intersect.