Suppression of HIV-associated Macrophage Activation by a p75 Neurotrophin Receptor Ligand.

Previous studies indicated that nerve growth factor (NGF) and proNGF differentially regulate the phenotype of macrophages and microglia via actions at tropomyosin receptor kinase A (TrkA) and p75 neurotrophin receptors (p75), respectively. The ability of HIV gp120 and virions to induce the secretion of factors toxic to neurons was suppressed by NGF and enhanced by proNGF, suggesting the potential for neurotrophin based "anti-inflammatory" interventions. To investigate the "anti-inflammatory" potential of the p75 ligand, LM11A-31, we treated cultured macrophages and microglia with HIV gp120 in the presence or absence of the ligand and evaluated the morphological phenotype, intrinsic calcium signaling, neurotoxic activity and proteins in the secretome.

Teaching Medical Students to Communicate With Empathy and Clarity Using Improvisation.

Problem: Medical educators widely accept that health care providers need strong communication skills. The authors sought to develop a course incorporating improvisation to teach health professions students communication skills and build empathy.

Approach: Teaching health care professionals to communicate more effectively with patients, the public, and each other is a goal of the Alan Alda Center for Communicating Science at Stony Brook University.

Opposing Effects of NGF and proNGF on HIV Induced Macrophage Activation.

Macrophage and microglial activation by HIV in the central nervous system (CNS) triggers the secretion of soluble factors which damage neurons. Therapeutic approaches designed to restore cognitive function by suppressing this inflammatory activity have not yet been successful. Recent studies have indicated that the phenotype of macrophages is differentially controlled by the mature and pro form of nerve growth factor.

Differential regulation of macrophage phenotype by mature and pro-nerve growth factor.

To characterize the role of neurotrophin receptors on macrophages, we investigated the ability of nerve growth factor (NGF) and its precursor, proNGF, to regulate human macrophage phenotype. The p75 neurotrophin receptor (p75(NTR)) and TrkA were concentrated within overlapping domains on membrane ruffles. NGF stimulation of macrophages increased membrane ruffling, calcium spiking, phagocytosis and growth factor secretion.

Cell trafficking through the choroid plexus.

The choroid plexus is a multifunctional organ that sits at the interface between the blood and cerebrospinal fluid (CSF). It serves as a gateway for immune cell trafficking into the CSF and is in an excellent position to provide continuous immune surveillance by CD4 (+) T cells, macrophages and dendritic cells and to regulate immune cell trafficking in response to disease and trauma. However, little is known about the mechanisms that control trafficking through this structure.

Pathogenesis of HIV-associated non-Hodgkin lymphoma.

In the current era of highly active antiretroviral therapy (HAART), the prevalence of HIV-associated non-Hodgkin lymphoma (H-NHL) is not as high as in the beginning of the acquired immunodeficiency syndrome (AIDS) epidemic, but still remains above that of non-HIV-infected individuals. Therefore, the epidemiology suggests that the pathogenesis of H-NHL may be multifactoral, involving the interaction of the immune system with HIV or other pathogens. Although HIV is a retrovirus, it is not characterized with the typical oncogenic potential associated with insertional mutagenesis.