NIKS® Progenitor Cell Line
Stratatech’s product lines – StrataGraft® and ExpressGraft™ skin tissues – are all based on the NIKS® human keratinocyte progenitor cell line. The cell line was derived from keratinocytes (the most common and least immunogenic of the cells found in the epidermis) which were isolated from a normal human infant tissue. Of the thousands of cell cultures used in Dr. Allen-Hoffmann’s lab at UW-Madison over two decades, cells in a single culture dish spontaneously became a “continuous cell line”. In other words, unlike cultured human keratinocytes from other normal skin tissue samples, the cell line can be grown indefinitely in the laboratory. The extensive study of the cell line has demonstrated that it is identical to normal human keratinocytes in its growth, differentiation and skin development properties.
The extraordinary value of the keratinocyte progenitor cell line is its ability to regenerate a fully stratified multi-layered human skin substitute with the physical strength and biological characteristics of intact human skin. In other words, when appropriately handled, a cultured cell product grows precisely as new human skin grows, exhibiting most of the physical, chemical, and histological properties of “real” skin, as well as stopping such growth when growth abuts neighboring keratinocytes. Because the cell line was established from a single cell and tested for and demonstrated to be absent of pathogens or diseases, NIKS cells can be utilized indefinitely to produce cultured skin, avoiding the costly and time-consuming need to periodically recreate and requalify new cell lines.
Even more important, having a well characterized clonal cell line as a foundation for its products allows Stratatech to pursue strategies to genetically enhance the cell line’s performance. This enabling capability makes possible the creation of skin substitutes that have enhanced antimicrobial properties, improved vascular function, and promote faster healing. No other skin substitutes either on the market or under development have this functionality. And importantly, introduction of new genetic traits is done without the use of viral vectors or other delivery technologies that could impart unwanted safety risks to the transgenic tissue.
A Paradigm Shift in Cutaneous Wound Healing
Stratatech’s technology has the potential to significantly impact the wound care market. Historically, negative pressure wound therapy has been the leading available treatment in the bioactive sector. More recently, biological dressings such as collagen products, growth factors, and first generation skin substitutes have emerged as important therapeutic tools. These products pioneered the shift in clinical focus from simple wound coverage or closure to strategies that modulate the underlying wound healing process. With the advent of Stratatech’s next-generation technology, a platform now exists to progress these capabilities to a new level by a) incorporating the potency of growth factors into skin substitutes, and b) creating bioactive skin substitutes with broad-spectrum antimicrobial properties. Various antimicrobial peptides and proteins could conceptually be produced in custom tissues, but most intriguing is the use of broad-spectrum innate host defense peptides, a well studied but to date untapped treatment strategy. Independent surgeons have referred to Stratatech’s unique ability to develop genetically enhanced tissues as a potential “paradigm shift in the management of skin pathologies”.
Viewed strategically, Stratatech’s unprecedented NIKS platform enables:
A superior second generation unmodified allogeneic skin substitute;
The first and only genetically enhanced skin substitutes;
A platform to utilize innate host defense peptides in wound healing;
A novel platform to expand skin substitutes beyond traditional wound healing into new therapeutic concepts.
Producing Full-Thickness Skin SubstitutesThe Company’s human tissue products are manufactured in a robust, highly reproducible process. In simplified terms, a dermal layer is formed by plating a mixture of collagen and fibroblast cells using standard tissue culture techniques. Once the collagen has gelled the NIKS cells are then plated on the collagen in our proprietary StrataLife™ medium. As they grow in the medium, the NIKS cells naturally differentiate into all the normal epidermal layers of human skin including the Basal, Spinous, Granular layers and ultimately form a true skin “barrier” or Stratum corneum. The resulting viable full-thickness tissue can either be used fresh, or frozen and inventoried for later use.
Stratatech currently produces its research grade products in its own facility and contracts cGMP tissue production with a qualified third party vendor.