Neglected advances

A series of research projects begun in 1994, which received FAPESP funding, has managed significant advances against Chagas Disease, culminating in an unprecedented cure in highly susceptible mice through a technology of DNA vaccines.

By Fábio de Castro, Rio de Janeiro

Agência FAPESP – A series of research projects begun in 1994, which received FAPESP funding, has managed significant advances against Chagas Disease, culminating in an unprecedented cure in highly susceptible mice through a technology of DNA vaccines.

Nevertheless, according to the project coordinator, Maurício Martins Rodrigues of Universidade Federal de São Paulo (Unifesp), there are still no prospects for conducting clinical trials, due to industry’s lack of interest.  Chagas Disease is considered a neglected disease.

The vaccination protocol utilized involves induction of CD8 T-cells against an antigen of Trypanosoma cruzi: a protein from the amastigote’s surface, which is a parasite in its intracellular stage. T-cells are white blood cells that are involved in immune response to tumors and infectious agents.

Rodrigues presented the model on August 25 during the Annual Meeting of the Federation of Experimental Biology Societies (FeSBE) in Rio de Janeiro.

According to Rodrigues, the research projects have generated innumerous studies, theses, reagents and patents, which are important for the possible development for a vaccine against Chagas Disease. The problem is that because it is a neglected disease, there has not been explicit interest by any company in generating a product for it. 
 

“The current situation is that we have generated every vector, the recombinant DNA proteins from experiments with animals, we obtained patents and we now need some type of contact with companies interested in producing this type of vaccine. In this research phase, this interest would have already been manifested if it did not involve Chagas Disease,” he told Agência FAPESP.

Rodrigues compares the situation of projects on Chagas Disease with his own projects that utilize the same models to study malaria. He currently coordinates the “Generation and analyses of the immunogenic properties of recombinant proteins based on the circumsporozoite antigen of Plasmodium vivax aiming at the development of a universal malaria vaccine,” a FAPESP-funded thematic project.

“In the area of vaccination against malaria, we are working with same strategy, but are utilizing a recombinant protein instead of plasmodial DNA. In this project, we managed to obtain a high level, international patent for the vaccine and we are constantly receiving contacts from companies with interest in developing any type of product. This has never occurred with the Chagas Disease project,” he explains.

Production of knowledge about the subject of Chagas Disease, however, is of extreme importance, even if the industry is not interested, according to Rodrigues. “Everything that we do for Chagas Disease is absolutely applicable to other diseases, including malaria, tuberculosis or HIV,” affirmed.

According to Rodrigues, the protocols utilized showed extreme efficiency. According to him, upon contact with Trypanosoma cruzi, the infected individual develops parasitemia, which characterizes the acute stage of disease. As the antibodies began to act, parasitemia diminishes and the disease enters a chronic phase, which could last the remainder of the host’s life in a balance that keeps the host and parasite alive.

“Nevertheless, some mice are highly susceptible and do not experience a reduction in parasitemia, dying while still in the acute stage. The protocol that we utilized induced the long term immunity and managed for the first time to cure this type of animal of Chagas Disease,” he explains.