A morphological screening of protein crystals for interferon delivery by metal ion-chelate technology.
OBJECTIVE
This study presents a preliminary exploration on extending the half-life of therapeutic proteins by crystallization strategy without new molecular entities generation.


METHODS
Recombinant human interferon (rhIFN) α-2b, a model protein drug in this case, was crystallized using a hanging-drop vapor diffusion method. A novel chelating technique with metal ions was employed to promote crystals formation.


RESULTS
The effects of key factors such as seeding protein concentration, pH of the hanging drop, ionic strength of the equilibration solution, and precipitants were investigated. Size-exclusion liquid chromatography, antiviral activity determination, and enzyme-linked immunosorbent assay indicated that both the molecular integrity and biological potency of rhIFN were not significantly affected by crystallization process. In addition, the in vitro release behavior of rhIFN from crystal lattice was characterized by an initial fast release, followed by a sustained release up to 48 hour.


CONCLUSIONS
The work described here suggested an exciting possibility of therapeutic protein crystals as a long-acting formulation.
Department of Pharmaceutics, School of Pharmaceutical Science, Shenyang Pharmaceutical University, Shenyang, China.
Yanbo
Y
Jiang
Kai
K
Shi
Shuo
S
Wang
Xuefeng
X
Li
Fude
F
Cui
D000998:Antiviral Agents / Q000737:chemistry* / Q000494:pharmacology; D002413:Cations, Divalent; D002478:Cells, Cultured; D002614:Chelating Agents / Q000737:chemistry*; D002626:Chemistry, Pharmaceutical; D002850:Chromatography, Gel; D003460:Crystallization; D003692:Delayed-Action Preparations; D004058:Diffusion; D004797:Enzyme-Linked Immunosorbent Assay; D006207:Half-Life; D006801:Humans; D006863:Hydrogen-Ion Concentration; D000077190:Interferon alpha-2; D016898:Interferon-alpha / Q000737:chemistry* / Q000494:pharmacology; D011994:Recombinant Proteins; D018116:Vesiculovirus / Q000187:drug effects; D015032:Zinc / Q000737:chemistry*
D000998:Antiviral Agents; D002413:Cations, Divalent; D002614:Chelating Agents; D003692:Delayed-Action Preparations; D000077190:Interferon alpha-2; D016898:Interferon-alpha; D011994:Recombinant Proteins; D015032:Zinc