title: Polymers for viral gene delivery.
abstract: BACKGROUND
  The development of viral vectors capable of providing efficient gene transfer in diseased tissues without causing any pathogenic effects is pivotal for overcoming the many challenges facing gene therapy.
  
  
  OBJECTIVE
  Immune responses against viral vectors, inadequate gene expression and inefficient targeting to specific cells in vivo are some of the major problems limiting the clinical utility of viral gene therapy.
  
  
  METHODS
  This review will focus on recent progress in strategic polymer-based modifications to improve the performance and biocompatibility of a variety of viral vectors. We will discuss the preclinical development of four approaches involving injectable polymers, polyelectrolytes, polymer microspheres and polymer-virus conjugates.
  
  
  CONCLUSIONS
  Much progress has been made in creating 'hybrid' gene delivery vectors that combine the strengths of polymers and viruses. With further optimization, these hybrid vectors, which may be safer and more effective, are likely to succeed in clinical applications.
authors.affiliation: University of Minnesota, Department of Biomedical Engineering, 7-105 Hasselmo Hall, 312 Church Street S.E., Minneapolis, MN 55455, USA. wangx504@umn.edu
authors.forename: Chun
authors.initials: C
authors.lastname: Wang
authors.forename: Phuong-Truc
authors.initials: PT
authors.lastname: Pham
mesh_terms: D000256:Adenoviridae / Q000235:genetics; D000818:Animals; D000229:Dependovirus / Q000235:genetics; D004573:Electrolytes / Q000737:chemistry; D018014:Gene Transfer Techniques; D015316:Genetic Therapy / Q000379:methods; D005822:Genetic Vectors / Q000737:chemistry*; D006801:Humans; D008863:Microspheres; D011108:Polymers / Q000737:chemistry*; D012190:Retroviridae / Q000235:genetics
chemical_list: D004573:Electrolytes; D011108:Polymers