Expandible microparticle intracellular delivery system
US5952232A · kind A · utility
Inventor
Key dates
| Filing date | Sep 17, 1998 |
| Grant date | Sep 14, 1999 |
| Priority date | — |
| Expiry date | Sep 17, 2018 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S977/92
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
The present invention relates to methods and compositions for delivery of a compound, most preferably a polynucleotide, into the cytoplasm of a cell by means of a microparticle, fabricated from a pH-sensitive hydrogel in collapsed phase, and having a size and physical characteristics compatible with uptake via a clathrin-coated pit on the cell surface. The trigger pH at which the hydrogel expands is lower than the physiological pH of the extracellular environment, allowing the microparticle, which comprises the compound to be delivered, to maintain its compact size prior to cellular uptake, thereby providing the additional benefit of protecting the comprised compound from degradation. This protective feature is particularly beneficial in embodiments in which a polynucleotide or a peptide is being delivered. Following uptake via a clathrin-coated pit, the microparticle then enters the intracellular endocytic pathway, where it is subjected to a progressive decrease in pH. Once the trigger pH for the hydrogel is reached, the microparticle increases its water content and expands, bursting its containing vesicle, and allowing its comprised compound to enter the cytoplasm. According to t…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.