Coating for electrodes of IL Receptors for brain

Technology
The present technology provides an electrode coated by a bioactive protein, designed for
chronic implantation into the central nervous system (CNS; brain or spinal cord). The bioactive
coating actively and significantly reduces the immune reaction to the chronically implanted
electrode. Thus, it prolongs the beneficial effects of deep brain and spinal cord stimulation
based therapies.
The Need
Implantation of electrodes for electrical deep brain stimulation (DBS) and spinal cord
stimulation are widely used for treatment of brain malfunctions such as Parkinson's disease
(PD), epilepsy, major depression, dystonia and essential tremor and for chronic pain. Reports
of a reduction in the efficacy of DBS therapy are heavily linked with the brain's immune
response to the chronically implanted electrodes. The immune reaction defines a time limit
for the beneficial therapeutic effects of neuronal stimulation due to the formation of a scar
tissue (glial scar) that encapsulates the chronic electrode. The current strategy to overcome
this biocompatibility challenge is systemic application of immune suppressing drugs or using
electrodes coated with soluble drugs. Yet, while the first strategy results in severe side effects
the latter is time limited. Our active bio-coating offers two main tools for reducing the
immune response; (a) the innate non-soluble coating protein, namely, interleukin 1 receptor
antagonist (IL1ra) camouflages the electrode from the immune system and (b) the IL1ra
actively and locally reduces the immune response, strongly limits the formation of scar tissue
and actively prolongs the efficacy of electrical stimulation therapy.
Potential Application
Present bioactive coating can be used for prolonging the therapeutic efficacy of deep brain
stimulation and chronic pain spinal cord stimulation. Thus it can be used in subjects with
Parkinson's disease (PD), epilepsy, major depression, dystonia and essential tremor and for
chronic pain.
Stage of Development
The bioactive coating was tested in an in-vivo rat model that were chronically implanted with
silicon electrodes as it is a common material for chronic electrodes. With very little
adaptation, the bioactive coating can be applied to a variety of materials including plastics,
silicon-based materials, metals and polymers. In an in-vivo rat model, the IL-1ra coated
electrodes initiated significantly less immune reaction i.e. glial scar when tested 1 and 4
weeks after implantation. Specifically, the bioactive electrode initiated ~50% and ~90% less
immune response compared to the commonly used silicon electrodes, when examined 1 and
4 weeks after implantation, respectively. Importantly, the beneficial effect of the bioactive IL-
1ra coated electrodes was demonstrated as it initiated ~60% less immune response compared
to an electrode which was coated with a non-active protein (laminin).

Patents
Publication WO 2013/018088
Supporting Publications
Taub, Aryeh H., et al. Bioactive anti‐inflammatory coating for chronic neural electrodes.
Journal of Biomedical Materials Research Part A 100.7 (2012): 1854-185

Project manager

Rona Samler
VP, BD Physical Science, Medical Device, Chemistry

Project researchers

Yosi Shacham- Diamand
T.A.U Tel Aviv University, Engineering
School of Electrical Engineering