Biomedical Engineering Reference
In-Depth Information
Alzheimer's disease with the local and long term administration of CNTF (ciliary
neurotrophic factor) using recombinant cells encapsulated with alginate secreting this
neurotrophin factor (Orive et al, 2010 & Keunen et al, 2011).
In recent years microencapsulation technology and gene therapy was combined to be use as
new therapy to deliver specific substances to target cell in brain tumours. The treatment of
brain tumours represents one of the most challenges in oncology. Many anti-cancer drugs
developed the last years did not provide effects in brain tumours due to impossibility of
cross the blood brain barrier. In particular, the developing of microcapsules loaded with
anti-cancer drug implanted into brain allows the treatment of tumours directly in the origin
of target cells. Some years ago, it was patented a new system for therapy of malignant brain
tumours (Keunen et al, 2011). This methodology used alginate-encapsulated H528 cells
releasing antibodies stabilized potentially inhibit a heterogeneous glioma cell population.
These microcapsules were implanted into brain and after slow and controlled distribution
within all cerebrospinal fluid compartments of the antibodies during 9 weeks, the glioma
were significantly reduced. This example can be apply for other potential anti-cancer drugs
combined with different producer cells increasing the specificity of the treatment and the
potential delivery system for specific brain tumours (Thorsen et al, 2000). Further, new
biomaterials are playing an increasingly important role in developing more effective brain
tumour treatments. This new biomaterials can also serve as targeted delivery devices for
novel therapies including gene therapy, photodynamic therapy, anti-angiogenic and
thermotherapy playing key roles in the diagnosis and imaging of brain tumours by
revolutionizing both preoperative and intraoperative brain tumour detection.
Monoclonal antibodies have been envisioned as useful agents for human therapeutic and
diagnostic applications
in vivo
. Recent results from human clinical trials suggest that this
potential is becoming a reality. Attention is now shifting to the development of methods to
produce monoclonal antibodies of a quality acceptable for widespread human use and in
sufficient quantity to be a commercially viable product. Microencapsulation technology has
been demonstrated to be suited to the large-scale production of both human and murine
monoclonal antibodies of high purity and activity, for use in applications
in vivo
. It was
previously comment the possibility of encapsulate antibodies for the treatment of brain
tumours. The same technology using anti-VE-cadherin monoclonal antibodies allowed open
a new alternative for the inhibition of angiogenesis and demonstrates the feasibility of using
microencapsulated cells as a control-drug delivery system (Orive et al, 2001). Also, it was
recently patented the use of human IgM antibodies encapsulated in alginate with
demonstrated activity in the treatment of demyelinating diseases as well as other diseases of
the central nervous system that are of viral, bacterial or idiopathic origin, including neural
dysfunction caused by spinal cord injury (Rodriguez et al, 2009).
Currently, there is ongoing several clinical trial where it is implicated the
microencapsulation technology. There is an interesting clinical trial to treat Parkinson's
disease with the product named Spheramine. This product, developed by Titan
Pharmaceuticals, is currently under safety and efficacy study. This product consists on
cultured human retinal pigment epithelial cells on microcarriers. These microcarriers are
implanted stereotaxically into both hemispheres of Parkinson's disease patients, and will be
evaluated during 24 months (NCT00206687 & NCT00761436). Another two clinical trials are
the work from Neurotech Pharmaceuticals to look at the safety and effectiveness of CNTF
