BACKGROUND:  Many types of human disorders may be treated by methods that transfer proteins or RNA into targeted cells. Some of these methods include the use of nanotechnology, synthetic liposomes, viral transduction, and electroporation. However, these current methods may require the use of potentially infectious agents and involves the risk of foreign DNA integration into the host genome. A new method of protein/RNA transfer involves the use of microvesicles (MVs), which are plasma membrane-derived. MVs are viewed as important mediators of intercellular communication and can transfer their contents from cell to cell.

INNOVATION:  UCLA investigators have identified embryonic stem cell microvesicles (MVs) that can be utilized in transferring proteins or RNA (including siRNAs and microRNAs) to targeted cells in order to treat human disorders. The desired protein or RNA to be transferred is first over-expressed in embryonic stem cells. Once the stem cells release MVs into culture, these MVs can be collected and engineered to target specific cells.

POTENTIAL APPLICATIONS 

• Transfer proteins or RNA (including siRNAs and microRNAs) into targeted cells to treat human disorders (i.e. loss of functional genes, suppressing expression of deleterious genes, influence developmental program of stem cells)

ADVANTAGES

• More physiological in nature
• Easily mass produced due to prolific nature
• Potential expansion of method to use "adult" stem cells

DEVELOPMENT-TO-DATE:  It has been demonstrated that stem cells can be successfully engineered to release microvesicles that contain GFP protein and RNA. Preliminary evidence show that GFP can be transferred to cells in vitro. Further developments are ongoing.

Reference: UCLA Case No. 2007-627