A team of researchers from the University of Florida, Gainesville (UF-G) and University of Pennsylvania (U-Penn) is developing a novel approach to tackling inhibitors in hemophilia A that uses genetically engineered plant cells. In a recent article published in the journal Blood, the authors reported making progress with the experimental therapy in mice with hemophilia A. The lead investigator of the study was Henry Daniell, PhD, Department of Biochemistry and Department of Pathology, School of Dental Medicine at U-Penn in Philadelphia.

Using genetically engineered plants, Daniell and his colleagues are developing therapeutic factor proteins that decrease unwanted treatment reactions such as anaphylaxis (a life-threatening allergic reaction) and inhibitor (antibody) responses by the immune system. The technique involves encapsulating a “tolerance-inducing protein” within plant cell walls so that when it is ingested it safely travels through the stomach before being released into the small intestines.

In this study, investigators synthesized tobacco plants and factor VIII-coded genetic material, which were fed to mice with hemophilia A. The therapy triggered an average of seven times fewer inhibitor responses. “This is a major step forward,” said study co-author Roland W. Herzog, PhD, College of Medicine, UF-G. In the future, the goal is to replace tobacco plants with lettuce plants for human use.

Researchers have been developing this novel therapeutic approach for several years to create potential vaccines against malaria and cholera, and genetically engineered insulin to help prevent diabetes. In previous studies led by Daniell, factor IX-bioencapsulated plant cells were successfully delivered to mice with hemophilia B. The therapy prevented both anaphylaxis and inhibitors.

The authors see a tremendous upside if this oral tolerance therapy were to become a viable option for humans. “Our technique, which uses plant-based capsules, has the potential to be a cost-effective and safe alternative,” said Daniell.

The article, “Suppression of Inhibitor Formation Against FVIII in a Murine Model of Hemophilia A by Oral Delivery of Antigens Bioencapsulated in Plant Cells,” was published in the September 4, 2014, issue of Blood.

Source: newKerala.com, September 4, 2014