Cloning and expression of proteins identified from the genome of the Leptospira interrogans sorovar Copenhageni bacteria with potential for vaccine use and in diagnosis

• Grant number: 04/09948-8
• Support Opportunities: Research Projects - Thematic Grants
• Start date: May 01, 2005
• End date: April 30, 2010
• Field of knowledge: Biological Sciences - Microbiology - Applied Microbiology
• Principal Investigator: Paulo Lee Ho
• Grantee: Paulo Lee Ho
• Host Institution: Instituto Butantan. Secretaria da Saúde (São Paulo - Estado). São Paulo , SP, Brazil
• Pesquisadores principais: Ana Lucia Tabet Oller do Nascimento ; Elizabeth Angelica Leme Martins
• Associated scholarship(s): 09/06962-3 - Characterization of the SOS response of Leptospira interrogans sorovar Copenhageni, BP.MS; 09/02316-0 - Characterization of membrane proteins of Leptospira interrogans expressed in Escherichia coli, BP.MS; 09/02317-6 - Expression and characterization of two surface proteins of Leptospira interrogans, BP.MS

Abstract

Leptospirosis is considered the most widespread zoonotic disease caused by the spirochaete from the Leptospira genus. Tn Brazil, 80% of all the diagnosed cases are due to Leptospira interrogans serovar Copenhageni. Rats are the main reservoir in urban centers and the bacteria are disseminated through animal urines. Around 10,000 cases of leptospirosis are annually notified to FUNASA (Health Ministry, Brazil), epidemically associated to the rainy seasons (http://www.funasa.gov.br). A promising way to treat this health problem would be a vaccination program, since the control of rats is a difficult task. Thus, the development of a suitable vaccine against leptospirosis is of seminal importance, since up to date, there is no licensed human vaccine against leptospirosis. Furthermore, the general clinical signs of this disease are often confounded with those of other diseases, like dengue and flu symptoms, reinforcing the need for an efficient diagnose assay for leptospirosis, not yet available in the market. Recently, the genome of the Leptospira interrogans serovar Copenhageni was described. The information of the genome would help to identify potential Leptospira vaccine antigen candidates or antigens for diagnose applications. The present project is divided in 3 subprojects, aiming: 1) cloning of 8 selected hemolysins. Recombinant proteins will be expressed in E. coli and further evaluated for their potential use as vaccine antigens and for potential use in diagnose. Biochemical and immunological characterization will also be performed; 2) cloning of 5 selected lipoproteins. Recombinant proteins will be expressed in E. coli and further evaluated for their potential use as vaccine antigens and for potential use in diagnose. Biochemical and immunological characterization will also be performed; 3) cloning and expression of 5 of the above antigens in Salmonella thyphimurium. The recombinant Salmonella will be evaluated as live vaccine against Leptospira. (AU)