Griffithsin

Griffithsin is a lectin protein originally isolated from red algae *Griffithsia* with potent broad-spectrum antiviral activity. It functions by binding to high-mannose oligosaccharides on viral envelope glycoproteins, preventing viral entry into host cells. Griffithsin exists as a domain-swapped homodimer with each subunit containing 121 amino acids and three carbohydrate binding sites. It demonstrates exceptional activity against numerous enveloped viruses including HIV, SARS-CoV, HCV, HSV-2, HPV, and JEV. For drug development, griffithsin is produced in tobacco plants and has shown an excellent safety profile in animal studies and early human trials.