T follicular helper (T(FH)) cells are a specialized subset of CD4(+) T cells that localize to B-cell follicles, where they are positioned to provide help for the induction of optimal humoral immune… (More)
Differentiation of B cells into Ig-secreting cells (ISC) is critical for the generation of protective humoral immune responses. Because of the important role played by secreted Ig in host protection… (More)
The p110δ subunit of phosphatidylinositol-3-OH kinase (PI(3)K) is selectively expressed in leukocytes and is critical for lymphocyte biology. Here we report fourteen patients from seven families who… (More)
High expression of CXCR5 is one of the defining hallmarks of T follicular helper cells (T(FH)), a CD4 Th cell subset that promotes germinal center reactions and the selection and affinity maturation… (More)
Engagement of cytokine receptors by specific ligands activate Janus kinase-signal transducer and activator of transcription (STAT) signaling pathways. The exact roles of STATs in human lymphocyte… (More)
Enhanced secondary Ab responses are a vital component of adaptive immunity, yet little is understood about the intrinsic and extrinsic regulators of naive and memory B cells that result in… (More)
The generation of Ig-secreting cells (ISCs) from memory B cells requires interactions between antigen-specific (Ag-specific) B cells, T cells, and dendritic cells. This process must be strictly… (More)
Humoral immune responses elicited after secondary exposure to immunizing Ag are characterized by robust and elevated reactivity of memory B cells that exceed those of naive B cells during the primary… (More)
T follicular helper (Tfh) cells are critical for providing the necessary signals to induce differentiation of B cells into memory and Ab-secreting cells. Accordingly, it is important to identify the… (More)
X-linked lymphoproliferative disease (XLP) is a severe immunodeficiency associated with a marked reduction in circulating memory B cells. Our investigation of the B cell compartment of XLP patients… (More)