Harvest of Vestibular End-Organs under Physiologic Conditions during Labyrinthectomy.

The living human inner ear is challenging to study because it is encased within dense otic capsule bone that limits access to biological tissue. Traditional temporal bone histopathology methods rely on lengthy, expensive decalcification protocols that take 9-10 months and reduce the types of tissue analysis possible due to RNA degradation. There is a critical need to develop methods to access fresh human inner ear tissue to better understand otologic diseases, such as Ménière's disease, at the cellular and molecular level.

A Benchtop Round Window Model for Studying Magnetic Nanoparticle Transport to the Inner Ear.

Introduction: The round window membrane (RWM) presents a significant barrier to the local application of therapeutics to the inner ear. We demonstrate a benchtop preclinical RWM model and evaluate superparamagnetic iron oxide nanoparticles (SPIONs) as vehicles for magnetically assisted drug delivery.

Methods: Guinea pig RWM explants were inset into a 3D-printed dual chamber benchtop device.

Engineering olivocochlear inhibition to reduce acoustic trauma.

Efferent brain-stem neurons release acetylcholine to desensitize cochlear hair cells and can protect the inner ear from acoustic trauma. That protection is absent from knockout mice lacking efferent inhibition and is stronger in mice with a gain-of-function point mutation of the hair cell-specific nicotinic acetylcholine receptor. The present work uses viral transduction of gain-of-function receptors to restore acoustic prophylaxis to the knockout mice.

Characterization of HA-tagged α9 and α10 nAChRs in the mouse cochlea.

Neurons of the medial olivary complex inhibit cochlear hair cells through the activation of α9α10-containing nicotinic acetylcholine receptors (nAChRs). Efforts to study the localization of these proteins have been hampered by the absence of reliable antibodies. To overcome this obstacle, CRISPR-Cas9 gene editing was used to generate mice in which a hemagglutinin tag (HA) was attached to the C-terminus of either α9 or α10 proteins.

Transplantation of human oligodendrocyte progenitor cells in an animal model of diffuse traumatic axonal injury: survival and differentiation.

Introduction: Diffuse axonal injury is an extremely common type of traumatic brain injury encountered in motor vehicle crashes, sports injuries, and in combat. Although many cases of diffuse axonal injury result in chronic disability, there are no current treatments for this condition. Its basic lesion, traumatic axonal injury, has been aggressively modeled in primate and rodent animal models.