title: Controlled release of interleukin-2 from chitosan microspheres.
abstract: Chitosan microspheres were evaluated for sustained-release of recombinant human interleukin-2 (rIL-2) in this study. In addition, the effects of different formulation factors, such as chitosan and protein concentrations, the volume of sodium sulfate solution, addition technique of rIL-2, and presence of glutaraldehyde during the encapsulation process, on microsphere characteristics were investigated. Chitosan microspheres containing rIL-2 were prepared by using the precipitation technique. The average diameter of microspheres was between 1.11-1.59 microm. Recombinant IL-2 encapsulation efficiency in these microspheres was high (75-98%). Formulation factors had no effect on the microsphere size. Recombinant IL-2 had been released from chitosan microspheres over a period of 3 months. The encapsulated rIL-2 remained biologically active and could be completely recovered from the release medium. Briefly, rIL-2 was released from chitosan microspheres in a sustained manner. The efficacy of rIL-2 loaded chitosan microspheres was studied using two model cells, HeLa and L-strain cell lines. Chitosan microspheres were added to the cells at different concentrations, and the amount of rIL-2 was assayed using the ELISA kit. Cell culture studies indicated that microspheres were uptaken by cells, and rIL-2 was released from the microspheres. Cellular uptake of rIL-2-loaded microspheres was dose dependent. It can be said that chitosan microsphere is a suitable carrier for rIL-2 delivery.
authors.affiliation: Department of Pharmaceutical Biotechnology, Faculty of Pharmacy, University of Marmara, 81010 Haydarpasa, Istanbul, Turkey.
authors.forename: Suna
authors.initials: S
authors.lastname: Ozbaş-Turan
authors.forename: Julide
authors.initials: J
authors.lastname: Akbuğa
authors.forename: Cenk
authors.initials: C
authors.lastname: Aral
mesh_terms: D018929:Cell Culture Techniques; D002626:Chemistry, Pharmaceutical; D002686:Chitin / Q000031:analogs & derivatives / Q000737:chemistry*; D048271:Chitosan; D003692:Delayed-Action Preparations; D004337:Drug Carriers; D006801:Humans; D007376:Interleukin-2 / Q000737:chemistry* / Q000378:metabolism; D008863:Microspheres; D010316:Particle Size; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism
chemical_list: D003692:Delayed-Action Preparations; D004337:Drug Carriers; D007376:Interleukin-2; D011994:Recombinant Proteins; D002686:Chitin; D048271:Chitosan