Immusoft is developing a cutting edge approach to sustained delivery of protein therapeutics using a patient’s own cells. The approach is called Immune System Programming (ISP™). ISP entails collecting a type of the patient’s immune cells, called B cells. In response to immune stimulation, B cells can turn into a biofactory state known as a plasma cell. Plasma cells manufacture and secrete thousands of antibodies per second. We harness this biofactory capability of the plasma cell by programming B cells to produce a given protein therapeutics.
Once we have programmed the B cells we expand the number of them many times and differentiate them into plasma cells (or, stated simply, coax them into the biofactory state) that produce massive amounts of our therapeutic protein. Thereafter we infuse the ISP™ programmed cells back into the same patient, where they take up residence and produce therapeutic proteins for extended periods of time.
Using a process called apheresis, we collect blood from a patient to obtain B cells — immune cells that are the building blocks of our therapeutic approach.
B cells are the precursor to plasma cells and are the ideal cells for us to modify because of their protein-producing capabilities. We select and purify these B cells to begin the process of programing and differentiation.
This is the gene transfer step. Using a non-viral gene delivery system, B cells are programmed with DNA to allow them to produce large amounts of therapeutic protein.
Using proprietary cell culture method, the programmed B cells are expanded and differentiated into plasma cells and plasmablasts — “biofactory” cells optimized for production and secretion of the therapeutic protein.
Programmed biofactory cells are injected back into patient. As with the blood collection in the first step, this step uses standard, conventional injection processes. The programmed cells circulate in the body and take up long-term residence in the tissues of the body, resulting in sustained in vivo cell-based drug delivery into the patient’s blood stream.
Once engrafted, the programmed cells produce therapeutic protein around the clock, for extended periods (possibly years), which acts to restore health of the patient.
B cells offer distinctive advantages of previous systemic (delivered in the blood stream) gene therapy / protein delivery approaches. Other gene therapy approaches predominantly entail injection of viruses that encode the therapeutic gene, or modification of stem cells that are re-injected into the patient.
In the case of virus delivery, there is currently no way to re-deliver the treatment. So, for a successful virus gene therapy, the following are required:
Because our approach is non-viral and uses the patients own cells, Immusoft envisions being able to give patients additional doses to overcome the above issues.
In the case of stem cell mediated gene delivery, patients must undergo extensive myeloablation (chemotherapy) to knock out the patients immune system to make room for the newly modified stem cells. Myeloablation can be a highly toxic and unpleasant procedure. Immusoft’s ISP approach does not require myeloablation.
The other approach we believe we will improve upon is direct infusion of proteins, with Enzyme Replacement Therapies being an initial target. Enzyme replacement therapies require weekly infusions that can take up to 4 hours at a time, starting with young children. Aside from the substantial disruption in the patient’s and caregivers’ lives, these enzymes do not last long and we believe patients would benefit from a sustained, steady-state delivery over extended periods.
B cells also offer the advantage of being able to produce a multitude of protein types. At Immusoft, we have successfully encoded B cells to produce enzymes, antibodies, structural proteins, and signaling proteins. Each of these protein types represents major opportunities to improve upon existing modalities or develop entirely new ones, potentially improving the lives of so many in need of better therapies.