Development of long-acting ciliary neurotrophic factor by site-specific conjugation with different-sized polyethylene glycols and transferrin

Publication date: 30 August 2017 Source:International Journal of Pharmaceutics, Volume 529, Issues 1–2 Author(s): Chun Zhang, Rong Yu, Zenglan Li, Cui Feng, Qi Wang, Yongdong Liu, Zhiguo Su To overcome the deficiency of rapid elimination from blood, the truncated human recombinant ciliary neurotrophic factor was formulated by site-specific attachment of different-sized PEG-maleimide or by cross-linking with human transferrin through a hetero-bi-functional PEG linker (NHS-PEG5k-MAL). The PEGylated CNTF was purified by a two-step chromatography procedure and the transferrin coupling CNTF conjugate was separated through an elegant protocol. The conjugation site on CNTF was identified by peptide mapping analysis and validated that the linkage of the conjugates was specifically happened to Cys17 residue. Although both PEGylated and transferrin coupling CNTF demonstrated decreased cell based residual activity, markedly enhanced pharmacokinetic behaviors in normal male Sprague-Dawley rats were observed, especially for the PEG40k-CNTF with approximately 58-times improvement compared with the unmodified counterpart. The evaluation of the in vivo potency of body weight-losing was performed with normal male C57BL6 mice and the results revealed that both PEGylation and transferrin coupling could achieve improved therapeutic benefits relative to that of CNTF. Besides, PEG20k/40k-CNTF demonstrated more effective than transferrin coupling CNTF (Tf-PEG5k-CNTF) despite that the lat...
Source: International Journal of Pharmaceutics - Category: Drugs & Pharmacology Source Type: research