Article

Aggregation of granulocyte colony stimulating factor under physiological conditions: characterization and thermodynamic inhibition.

Department of Pharmaceutical Sciences, School of Pharmacy, University of Colorado Health Sciences Center, Denver, Colorado 80262, USA.
Biochemistry (impact factor: 3.42). 06/2002; 41(20):6422-31. DOI:10.1021/bi012006m pp.6422-31
Source: PubMed

ABSTRACT We have investigated the aggregation of recombinant human granulocyte colony stimulating factor (rhGCSF), a protein that rapidly aggregates and precipitates at pH 6.9 and 37 degrees C. We observed that native monomeric rhGCSF reversibly forms a dimer under physiological conditions and that this dimeric species does not participate in the irreversible aggregation process. Sucrose, a thermodynamic stabilizer, inhibits the aggregation of rhGCSF. We postulate that sucrose acts by reducing the concentration of structurally expanded species, consistent with the hypothesis that preferential exclusion favors most compact species in the native state ensemble. Thermodynamic stability data from unfolding curves and hydrogen-deuterium exchange experimental results support the above hypothesis. Thus, the strategy of stabilizing the native state of the protein under physiological conditions using thermodynamic stabilizers, especially ligands binding with high affinity to the native state, is expected to protect against protein aggregation occurring under such nonperturbing solution conditions.

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    Article: Native-state solubility and transfer free energy as predictive tools for selecting excipients to include in protein formulation development studies.
    Douglas D Banks, Ramil F Latypov, Randal R Ketchem, Jon Woodard, Joanna L Scavezze, Christine C Siska, Vladimir I Razinkov
    [show abstract] [hide abstract]
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    Journal of Pharmaceutical Sciences 05/2012; 101(8):2720-32. · 3.06 Impact Factor
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.

Keywords

aggregates
 
compact species
 
dimeric species
 
hydrogen-deuterium exchange experimental results support
 
irreversible aggregation process
 
ligands binding
 
native monomeric rhGCSF reversibly forms
 
native state
 
native state ensemble
 
nonperturbing solution conditions
 
physiological conditions
 
preferential exclusion
 
protein aggregation
 
recombinant human granulocyte colony stimulating factor
 
rhGCSF
 
structurally
 
sucrose acts
 
Thermodynamic stability data
 
thermodynamic stabilizer
 
thermodynamic stabilizers