Expression of T. gondii SAG1 antigen fused to L. infantum Hsp83 in tobacco transplastomic plants.

LAGUIA BECHER M; YACONO M. L.; FARRAN I; VERAMINDI J; CLEMENTE M

Madryn

Otro; XLVI Reunión Anual Sociedad Argentina de Investigación en Bioquímica y Biología Molecular; 2010

SAIB

We have previously determined that it was feasible to produce a T.gondii SAG1 vaccine in plant by transient protein expression. This vaccine could be used in oral and subcutaneous immunization protocols. Chloroplast transformation has the capacity to accumulate high levels of recombinant proteins and increased biosafety due to maternal plastid inheritance. Here, we evaluate tobacco chloroplast transformation for the production of T. gondii SAG1 antigen to increase accumulation levels. We evaluated the expression levels of two constructs. In one of them, the SAG1 peptide was expressed alone and in the other, the antigen was expressed as a fusion protein with L. infantum Hsp83, which showed a considerable efficacy to induce a strong humoral and cellular immunoresponse. Our results showed that the expression levels of SAG1 were significantly increased when the protein was fused to LiHsp83. The recombinant protein represented more than 5% of the total soluble proteins in mature leaves. Despite the fact that the transplastomic plants expressing the LiHsp83-SAG1 showed a clorotic color in their leaves, they could give flowers and fructify normally. Here we demonstrated that LiHsp83 is a good candidate to carry antigens by increasing the polypeptide production. In addition, the LiHsp83 adjuvant properties could improve the immunogenicity property of the transgenic plant extract.T.gondii SAG1 vaccine in plant by transient protein expression. This vaccine could be used in oral and subcutaneous immunization protocols. Chloroplast transformation has the capacity to accumulate high levels of recombinant proteins and increased biosafety due to maternal plastid inheritance. Here, we evaluate tobacco chloroplast transformation for the production of T. gondii SAG1 antigen to increase accumulation levels. We evaluated the expression levels of two constructs. In one of them, the SAG1 peptide was expressed alone and in the other, the antigen was expressed as a fusion protein with L. infantum Hsp83, which showed a considerable efficacy to induce a strong humoral and cellular immunoresponse. Our results showed that the expression levels of SAG1 were significantly increased when the protein was fused to LiHsp83. The recombinant protein represented more than 5% of the total soluble proteins in mature leaves. Despite the fact that the transplastomic plants expressing the LiHsp83-SAG1 showed a clorotic color in their leaves, they could give flowers and fructify normally. Here we demonstrated that LiHsp83 is a good candidate to carry antigens by increasing the polypeptide production. In addition, the LiHsp83 adjuvant properties could improve the immunogenicity property of the transgenic plant extract.