A novel platform for in vivo detection of cytokine release within discrete brain regions, Zhang et al, 2018

[Indigophoton]

A way to measure cytokine levels in vivo using essentially a biologically coated optical fibre guided into the brain via a stereotactically positioned guide cannula.

Potentially of interest for real-time monitoring in ME if cytokines in the brain are relevant.

Highlights
An optical fibre based in vivo device capable of monitoring of local cytokine release in discrete brain regions has been designed.

The immunocapture device can be introduced into a perforated guide cannula for repeated cytokine measurements in vivo.

This novel immunosensing technology provides an opportunity for unlocking the function of neuroimmune signaling.

Abstract
Mounting evidence indicates that cytokines secreted by innate immune cells in the brain play a central role in regulating neural circuits that subserve mood, cognition, and sickness responses. A major impediment to the study of neuroimmune signaling in healthy and disease states is the absence of tools for in vivo detection of cytokine release in the brain. Here we describe the design and application of a cytokine detection device capable of serial monitoring of local cytokine release in discrete brain regions.

The immunocapture device consisted of a modified optical fiber labeled with a capture antibody specific for the pro-inflammatory cytokine interleukin-1 beta (IL-1β). Using a sandwich immunoassay method, in vitro data demonstrate that the sensing interface of the modified optical fiber has a linear detection range of 3.9 pg mL-1 to 500 pg mL-1 and spatial resolution on the order of 200-450 μm.

Finally, we show that the immunocapture device can be introduced into a perforated guide cannula for repeated analyte measurements in vivo. An increase in fluorescence detection of spatially localized
intrahippocampal IL-1β release was observed following a peripheral lipopolysaccharide challenge in Sprague-Dawley rats. This novel immunosensing technology represents an opportunity for unlocking the function of neuroimmune signaling.

Biological communication in the central nervous system (CNS) involves complex and interconnected networks of cells that use a variety of chemical signals supporting information processing. Multiple lines of evidence indicate that immune responses generated in the CNS are mediated, in part, by pro-inflammatory cytokines that orchestrate aspects of sickness behavior such as shifts in motivational priorities, sensory processing, and cognitive performance (Larson, 2002; Maier, 2003; Rohan Walker and Yirmiya, 2016; Watkins et al., 1995).

These molecular signals originate from resident innate immune cells in the CNS (e.g., microglia) that serve as the neuroimmune substrate for de novo synthesis and release of central cytokines, most notably the prototypic pro-inflammatory cytokine interleukin-1 beta (IL-1β) (Dinarello, 2011; Frank et al., 2007; Kreutzberg, 1996).

However, our understanding of these neuroimmune signals in neuroinflammatory processes has been hampered, in large part, due to several limitations of current experimental approaches for the measurement of cytokines in the brain. The most common approaches, including immunohistochemical and ELISA based techniques, are restricted to quantifying total cytokine levels, but fail to capture interstitial cytokine levels or cytokine release in discrete brain regions.

Conclusion
Studies of neuroinflammatory processes typically evaluate total cytokine levels within brain regions using either ELISA or immunohistochemical approaches, which precludes determination of cytokine release into the interstitial space in discrete brain regions. In addition, these approaches are limited to a single measurement in time, thus requiring a between subjects design to capture cytokine changes across time after an immune challenge. The present study characterizes an innovative approach, which addresses both of these methodological limitations inherent to ELISA and immunohistochemical approaches.

Given the role of neuroimmune communication in the etiology of numerous psychiatric disorders (Jones and Thomsen, 2013), this technology provides a novel strategy for monitoring the release of cytokine proteins from innate immune cells in discrete neural circuits, and it has the potential to elucidate pathological dynamics underlying neuropsychiatric disease.

https://www.sciencedirect.com/science/article/pii/S0889159118301302?via=ihub

The paper, https://doi.org/10.1016/j.bbi.2018.04.011, available currently via sci-hub.tw.

Edit: accuracy.

 

[alktipping]

certainly not volunteering for that procedure. who would want to run al the risks involved just to be told there is no real treatment anyway.