|
|
|
|
|
|
|
|
|
| |
|
| |
| |  Most vaccines are delivered by injection, which increases the risk that HIV, hepatitis, and other serious diseases may be transmitted by syringes and needles that are not sterile. Dr. Alonso's team is working to develop a new generation of delivery systems that can easily and effectively carry hepatitis B vaccine through the mucosal lining of the nose. In addition, the team is evaluating whether these delivery systems and the vaccine they carry can be freeze-dried into an inhaled powder that could be stored without refrigeration.
The project team is exploring a number of different chemical structures, or "nanocarriers" for delivering the hepatitis B vaccine through the nose. Such a delivery system has the potential to eliminate the need for syringes and needles and to provide an improved vaccine that is easier to administer.
In searching for a potential nanocarrier, the team is studying whether different chemical structures can:
- Easily cross mucosal surfaces, which may increase the efficiency and effectiveness of the immunization.
- Effectively distribute the vaccine in a controlled manner.
- Elicit an immune response in animal models.
|
| | |
| | | To develop a needle-free vaccination approach based on the design of nanocarriers that are able to transport antigens across mucosal surfaces and to deliver the nanoencapsulated antigen in an improved controlled manner | | | | | To apply these nanosystems to the easy delivery of hepatitis B surface antigen through the nasal route and, hence to improve the protection coverage against hepatitis B | | |
| |
| | BACK TO THE TOP |
| | |
| | Dr. Alonso's team has developed four nanocarrier prototypes:
• Chitosan nanoparticles,
• PLGA:poloxamer nanoparticles,
• Chitosan-PLBA:poloxamer nanoparticles,
• PLGA-PEG nanoparticles. | | | | | In collaboration with another Grand Challenges research group, led by Dr. David Edwards of Harvard University, Dr. Alonso's team has converted two of the prototypes, chitosan and PLGA-PEG, to a dry powder that might be inhaled as a vehicle for vaccine delivery. | | | | | Using ELISA and Western-Blot analyses, the team has found that all four nanocarrier prototypes can encapsulate active vaccine and release it gradually. Testing has indicated that the new vaccine remains stable over the 14-day course of its release. | | | | | After storage at 4 degrees Celsius (about 39 degrees Farenheit), the encapsulated vaccine retained its ability to elicit an immune response for 14 days. After freeze-drying, the physiochemical properties of the nanocarriers and the structural integrity of the encapsulated vaccine were retained. | | | | | CS and PLGA-Poloxamer nanoparticles that carried fluorescent markers crossed the nasal mucosa of rats 15 minutes after administration. | | | | | PLGA-Poloxamer nanoparticles labeled with a radioactive marker and administered to rats were highly retained in the nasal mucosa, while PLGA-PEG nanoparticles were less well retained but more accessible to the lymph nodes. | | | | | After administering the four prototypes and fluid vaccine to mice, the team found that when the vaccine was encapsulated, only PLGA-PEG nanoparticles provided a significant response. However, when the vaccine was mixed with the nanoparticles, other prototypes elicited a comparable response. | | |
| |
| | BACK TO THE TOP |
| | | |
| | | Advancell, Spain - ES | | | | | University of Vigo, Vigo, Spain - ES | | | | | Dr. David Edwards, Harvard University / Medicine in Need, Massachusetts, United States - US | | | | | Duke University, North Carolina, United States - US | | | | | University of Montana, Montana, United States - US | | |
| |
| | BACK TO THE TOP |
|
|
|
|
|
|
|
|
|
|
|