Optical techniques in optogenetics

Abstract

Optogenetics is an innovative technique for optical control of cells. This field has exploded over the past decade or so and has given rise to great advances in neuroscience. A variety of applications both from the basic and applied research have emerged, turning the early ideas into a powerful paradigm for cell biology, neuroscience and medical research. This review aims at highlighting the basic concepts that are essential for a comprehensive understanding of optogenetics and some important biological/biomedical applications. Further, emphasis is placed on advancement in optogenetics-associated light-based methods for controlling gene expression, spatially-controlled optogenetic stimulation and detection of cellular activities.

Optical delivery of multiple opsin-encoding genes leads to targeted expression and white-light activation

“…The optogenetic activation method is very promising because it requires only a low intensity of light, which can be delivered by a light-emitting diode or laser [7][8][9][10] . In addition, optogenetic approaches offer several advantages over electrical stimulation, such as cellular specificity, high temporal and spatial resolution, and minimal invasiveness [7][8][11][12][13][14] . However, the clinical translation of optogenetic activation for vision restoration suffers from the lack of a method for the delivery of opsinencoding genes into spatially targeted regions of a retina that has degenerated (e.g., the periphery of the retina in retinitis pigmentosa (RP) or the macula in age-related macular degeneration (AMD).…”

Therapeutic Potential of Optogenetic Treatment for Individuals with Multiple Sclerosis

“…Although beneficial for research, these methods are not viable translational strategies for human treatment. Moreover, these methods possess limitations such as not being able to specifically target cells, posing a risk to cellular components or the foreign DNA, and association with axonal pathology (Bryson et al, 2016;Mohanty & Lakshminarayananan, 2015). Due to the lack in cell specific targeting and the lack of lateralization to humans of non-viral methods, it seems viral delivery methods provide the most sensible means of creating an optogenetic treatment, especially when studied in non-human primate models.…”

“…Non-viral delivery methods of expressing ChR2 in cells include in utero electroporation, transgenic models, chemical lipofection, and laser-assisted cellular poration (Boyden et al, 2005;Carter & de Lecea, 2011;Mohanty & Lakshminarayananan, 2015). Although beneficial for research, these methods are not viable translational strategies for human treatment.…”

“…Ultimately, furthering this therapeutic tool is limited by the knowledge present for specific symptoms as well as their mechanisms (Bryson et al, 2016;Jazayeri & Remington, 2016;Mohanty & Lakshminarayananan, 2015;Mudiayi et al, 2015). Just as optogenetics may be used as a therapeutic tool, it can be utilized to understand these symptoms as it is currently used as an investigative tool (Carter & de Lecea, 2011;Mohanty & Lakshminarayananan, 2015;Mudiayi et al, 2015).…”

“…Just as optogenetics may be used as a therapeutic tool, it can be utilized to understand these symptoms as it is currently used as an investigative tool (Carter & de Lecea, 2011;Mohanty & Lakshminarayananan, 2015;Mudiayi et al, 2015). A first step to identifying how photostimulation can lead to therapeutic effects could ultimately be using optogenetics to understand individual symptoms by experimenting with its circuitry and inhibiting or activating symptom pathways.…”