Discovery (Lead Identification)
Virus entry into a susceptible host cell is the first step in the formation of all viral diseases. Controlling viral infections by disrupting viral entry is advantageous for antibody-mediated neutralization by the host’s immune system and as a preventive and therapeutic antiviral strategy. Plant-derived carbohydrate-binding proteins (lectins) have emerged as a new class of antiviral biologics by taking advantage of a unique glycosylation pattern only found on the surface of viruses.
This technology describes the lectin, Griffithsin (GRFT), isolated from red algae. GRFT shows significant broad-spectrum anti-viral activity making it a promising agent for use as a general microbicide that can prevent viral transmission and as a therapeutic against enveloped virus-mediated diseases. The patent rights for this technology cover the sequence of the GRFT polypeptide as well as several GRFT variants mutated to render them glycosylation-resistant. The patent rights also cover GRFT conjugates, compositions, nucleic acids, vectors, host cells, antibodies and methods of their production and methods of use. The broad spectrum anti-viral activity of GRFT has been attributed to its ability to inhibit viral binding, fusion and entry into the host cells by binding to viral envelope gp120. GRFT has potential as a therapeutic or prophylactic for retroviral infections including HIV-1 and HIV-2 as well as FIV, SIV, MLV, BLV, equine infectious virus, avian sarcoma viruses, and HTLV. In addition, Griffithsin could be used in combination with other anti-viral agents to treat patients who have drug-resistant virus.
A related NCI invention, reference number E-025-2006, further covers the use of Griffithsin against viral infection including Hepatitis C, Severe Acute Respiratory Syndrome (SARS), H5N1, or Ebola.
Researchers at the NCI seek licensing and/or co-development research collaborations for anti-viral Griffithsin (GRFT) proteins. Issued patents include US 7,884,178, US 8,394,764, with foreign rights in Canada, Australia, Japan, Israel, New Zealand, South Africa, France, Germany, Ireland, Switzerland, United Kingdom (all granted).