Patarroyo: "We have … a rational and logical methodology to develop vaccines against 517 transmittable diseases."

SciDev/Lisbeth Fog

[BOGOTÁ] A Colombian research group has chemically synthesised an early-stage malaria vaccine candidate in the laboratory.

Manuel E. Patarroyo and Manuel A. Patarroyo, director and researcher of the Colombian Institute of Immunology Foundation respectively, chemically synthesised protein fragments of the malaria parasite Plasmodium falciparum involved in red blood cell invasion.

They adapted their structures and tested them in Aotus monkeys until an immune response was initiated.

Patarroyo's research group has been working on the technique to chemically synthesise vaccines for over 30 years. He produced a first generation malaria vaccine in 1986, known as SPf66, which provided 35 per cent protection in people older than one year in field trials. Patarroyo hopes this second generation drug can be tested on humans in 2009.

Producing vaccines in the laboratory by this method — rather than the traditional method of using whole microorganisms — has several advantages, Patarroyo told SciDev.Net.

He says that the vaccines will be effective against multiple microorganisms and at different stages of the infection process. Additionally, batches of vaccine will always be exactly the same, and will not induce side effects. They are also stable at room temperature and cheap to produce, making them attractive for developing countries.

The researchers say their 'peptidoteque'— library of protein fragments that induce an immune response — is the key to fighting diseases such as malaria, tuberculosis, hepatitis, leishmaniasis, and cervical cancer.

"What we have been chasing along these 30 years is a rational and logical methodology to develop vaccines against 517 transmittable diseases," said Manuel E. Patarroyo to SciDev.Net.

"[The study] is a summary of at least ten years of continuous and exhaustive analysis of how a parasite — in this case Plasmodium falciparum — tries to avoid the immune attacks of its host and how manipulation of the immune response can overcome such avoidance strategies," Johan Hoebeke, visiting professor in bioinformatics at the Catholic University of Valparaiso, Chile, told SciDev.Net.

"[The work] will lead to a better understanding of the vaccination process and thus open the way for a real breakthrough vaccine."

The findings are published in Accounts of Chemical Research.

Link to abstract in Accounts of Chemical Research