Interplay between biochemical processes and network properties generates neuronal up and down states at the tripartite synapse.

Neuronal up and down states have long been known to exist both in vitro and in vivo. A variety of functions and mechanisms have been proposed for their generation, but there has not been a clear connection between the functions and mechanisms. We explore the potential contribution of cellular-level biochemistry to the network-level mechanisms thought to underlie the generation of up and down states.

Bifunctional Anti-Non-Amyloid Component α-Synuclein Nanobodies Are Protective In Situ.

Misfolding, abnormal accumulation, and secretion of α-Synuclein (α-Syn) are closely associated with synucleinopathies, including Parkinson's disease (PD). VH14 is a human single domain intrabody selected against the non-amyloid component (NAC) hydrophobic interaction region of α-Syn, which is critical for initial aggregation. Using neuronal cell lines, we show that as a bifunctional nanobody fused to a proteasome targeting signal, VH14PEST can counteract heterologous proteostatic effects of mutant α-Syn on mutant huntingtin Exon1 and protect against α-Syn toxicity using propidium iodide or Annexin V readouts.

Intrabodies as neuroprotective therapeutics.

The process of misfolding of proteins that can trigger a pathogenic cascade leading to neurodegenerative diseases largely originates intracellularly. It is possible to harness the specificity and affinity of antibodies to counteract either protein misfolding itself, or the aberrant interactions and excess stressors immediately downstream of the primary insult. This review covers the emerging field of engineering intracellular antibody fragments, intrabodies and nanobodies, in neurodegeneration.

Fusion to a highly charged proteasomal retargeting sequence increases soluble cytoplasmic expression and efficacy of diverse anti-synuclein intrabodies.

Intrabodies can be powerful reagents to effect modulation of aberrant intracellular proteins that underlie a range of diseases. However, their cytoplasmic solubility can be limiting. We previously reported that overall charge and hydrophilicity can be combined to provide initial estimates of intracellular solubility, and that charge engineering via fusion can alter solubility properties experimentally.

Endotoxin-induced maturation of monocytes in preterm fetal sheep lung.

The fetal lung normally contains immature monocytes and very few mature macrophages. The chorioamnionitis frequently associated with preterm birth induces monocyte influx into the fetal lung. Previous studies demonstrated that monocytes in the developing lung can mediate lung injury responses that resemble BPD in humans.

Vascular changes after intra-amniotic endotoxin in preterm lamb lungs.

Chorioamnionitis is associated with preterm delivery and bronchopulmonary dysplasia (BPD), characterized by impaired alveolar and pulmonary vascular development and vascular dysfunction. To study the vascular effects in a model of chorioamnionitis, preterm lambs were exposed to 20 mg of intra-amniotic endotoxin or saline for 1, 2, 4, or 7 days and delivered at 122 days gestational age (term = 150 days). This intra-amniotic endotoxin dose was previously shown to induce lung maturation.