Ultraviolet beam cleans up blood

17 Jun 2002

A new technique developed by US company Cerus could offer an affordable route to infection-free blood supplies.

The risk of contracting HIV and other infectious diseases from blood transfusions in the US could be reduced by a light-based sterilization technique developed by Californian company Cerus. The method uses ultraviolet light to kill viruses, bacteria and other parasites. The light, fired directly at the blood sample, causes a specially designed molecule to bind to and destroy parts of the DNA in the organisms while leaving other elements of the blood intact.

Cerus patented the technique, named Helinx, earlier this year (US 6171777). The company secured USD 78 million in funding last month, which it intends to use for research and development, including late-stage clinical trials and pre-commercialization activities. The method does not yet have US Food and Drug Administration approval, but this is anticipated for 2002.

"We believe the use of compounds that target DNA or RNA is the most efficient method of inactivating pathogens in blood products, which is why we are developing our nucleic acid binding Helinx technology," said Stephen Isaacs, president and CEO of Cerus.

Helinx uses a molecule named psoralen S-59 to penetrate cells, viruses, bacteria and other pathogens. Once inside, the molecule seeks out DNA and RNA and docks between the rungs of the DNA spiral. When illuminated with ultraviolet light, each end of the psoralen molecule reacts with either of two types of DNA base (pyrimidine C or T) to form a cross-linking structure within the DNA molecule. This renders the pathogen incapable of replication. The company states that platelets, plasma and red blood cells are not affected by this process.