Superresolution Imaging Reveals the Spatial Organization of CD81 Microdomains in Regulating Membrane Signaling on Jurkat T Cell Microvilli.

Tetraspanin proteins are closely associated with high-curvature membrane structures and play key roles in organizing membrane domains and regulating membrane signaling in immune cells. However, their specific roles in regulating T cell membrane signaling, particularly within the microvilli often characteristic of these cells, remain poorly understood. Here, we used Jurkat T cells as a model system and investigated CD81 as a member of the tetraspanin family.

The GATA-3-dependent transcriptome and tumor microenvironment are regulated by eIF4E and XPO1 in T-cell lymphomas.

The transcription factor GATA-3 and the transcriptional program it regulates have emerged as oncogenic drivers across diverse T-cell lymphomas (TCL), many of which are resistant to conventional chemotherapeutic agents and characterized by recurrent losses of key tumor suppressor genes, including TP53 and PTEN, both of which are clients of the nuclear export protein XPO1. Here we demonstrated that XPO1 is highly expressed by malignant T cells expressing GATA-3 and by lymphoma-associated macrophages (LAM) within their tumor microenvironment (TME). Using complementary genetically engineered mouse (GEM) models, we demonstrated that TP53 and/or PTEN deficient TCL, and LAM within their TME, are sensitive to the selective XPO1 antagonist selinexor.

Increased vesicular dynamics and nanoscale clustering of IL-2 after T cell activation.

T cells coordinate intercellular communication through the meticulous regulation of cytokine secretion. Direct visualization of vesicular transport and intracellular distribution of cytokines provides valuable insights into the temporal and spatial mechanisms involved in regulation. Employing Jurkat E6-1 T cells and interleukin-2 (IL-2) as a model system, we investigated vesicular dynamics using single-particle tracking and the nanoscale distribution of intracellular IL-2 in fixed T cells using superresolution microscopy.

Analysis of the bone fracture targeting properties of osteotropic ligands.

Purpose: Although more than 18,000,000 fractures occur each year in the US, methods to promote fracture healing still rely primarily on fracture stabilization, with use of bone anabolic agents to accelerate fracture repair limited to rare occasions when the agent can be applied to the fracture surface. Because management of broken bones could be improved if bone anabolic agents could be continuously applied to a fracture over the entire course of the healing process, we undertook to identify strategies that would allow selective concentration of bone anabolic agents on a fracture surface following systemic administration. Moreover, because hydroxyapatite is uniquely exposed on a broken bone, we searched for molecules that would bind with high affinity and specificity for hydroxyapatite.