Complement Depletion with Humanized Cobra Venom Factor in a Mouse Model of Age-Related Macular Degeneration

  • David C. Fritzinger
  • Robin Dean
  • Carol Meschter
  • Katina Wong
  • Roman Halter
  • Jürgen Borlak
  • William D. St. John
  • Carl-Wilhelm Vogel
Conference paper
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 703)


The effect of complement depletion with humanized cobra venom factor (CVF) on retinal lesion development/neovascularization was determined in a mouse model of wet age-related macular degeneration (AMD). Mice were treated with the humanized CVF protein HC3-1496 prior to, and once daily for 28 days after laser coagulation surgery of the retina. CVF transgenic mice exhibiting permanently low levels of serum complement activity and PBS-treated mice served as positive and negative controls, respectively. Fluorescein isothiocyanate (FITC)-dextran funduscopy after laser surgery indicated the presence of lesions in all mice that underwent laser surgery. In HC3-1496-treated mice as well as CVF transgenic mice smaller lesions were seen after 8 days. Measurement of lesion sizes by histopathological examination of eyes after 28 days revealed a significant reduction of lesion area and volume in both HC3-1496-treated animals and CVF transgenic animals compared to PBS-treated control animals. Systemic complement depletion with a complement depletor, such as the humanized CVF protein HC3-1496, represents a promising therapeutic concept for patients with wet AMD.


Retinal Pigment Epithelium Laser Surgery Choroidal Neovascularization Membrane Attack Complex Retinal Pigment Epithelium 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



We thank Dr. Cynthia Cook for performing the laser surgery. Biostatistical support is gratefully acknowledged from the Biostatistical Shared Resource of the Cancer Research Center of Hawaii. This study was supported, in part, by Incode Biopharmaceutics, Inc., San Diego, CA.


D. Fritzinger, W. St. John, and C.-W. Vogel have a financial interest in Incode Biopharmaceutics, Inc., San Diego, CA.


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Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  • David C. Fritzinger
    • 1
  • Robin Dean
  • Carol Meschter
  • Katina Wong
  • Roman Halter
  • Jürgen Borlak
  • William D. St. John
  • Carl-Wilhelm Vogel
  1. 1.Cancer Research Center of HawaiiUniversity of Hawaii at ManoaHonoluluUSA

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