Researchers from the Biodesign Institute, Arizona State University have successfully produced Plague vaccines from Tobacco plants. The researchers were able to produce vaccines from bioengineered plant which is found to be effective against guinea pigs which were exposed to pneumonic plague bacterium. The researchers are to start a clinical trial of the new vaccine in human to study the efficacy of the new vaccine. The researchers have reported the results of this study n the Journal Proceedings of the National Academy of Sciences.
Plague is an infectious disease caused by the bacterium Yersinia pestis, transmission mostly occurs by transmission of bacterium from rodent flea bite or handling of infected animal. Pneumonic plague can occur by inhaling infected droplet containing the flea. WHO has reported an early outbreak of 1000-3000 plague cases every year. Plague causes painful swollen lymph node with fever and exhaustion. The infection is highly progressive and can lead to fatality if antibiotic treatment is started immediately after diagnosis.
Though natural plague bacterium have been effectively controlled there as been an increased threat of genetically modified resistant strains of Yersinia pestis produced as a bioweapon to cause bio terrorism. Scientists are not sure whether these antibiotics would work effectively against this mutated bacterium which has led to an increase need to produce vaccine against plague infection.
Researchers have produced Recombinant subunit vaccines against plague by using two plague antigens F1, V and a combination of these two antigens as it gives the option of producing the required antigen vaccines depending on the strain of the bacterium which causes the outbreak. By injecting the antigens in the plant the researchers were able to produce high quantity of stable antigens within 10 days of infecting the plant, when injecting on guinea pigs either intramuscular or subcutaneous the guinea pigs produced high levels of stable antigens which immunizes the body of the guinea pig with antibodies against the required strain of the bacterium and when challenged with a dosage of Yersinia pestis bacterium the guinea pig antibodies were found to counteract these bacterium and produce an effective immunity killing these bacterium.