Production of rotavirus-like particles in tomato (Lycopersicon esculentum L.) fruit by expression of capsid proteins VP2 and VP6 and immunological studies.
A number of different antigens have been successfully expressed in transgenic plants, and some are currently being evaluated as orally delivered vaccines. Here we report the successful expression of rotavirus capsid proteins VP2 and VP6 in fruits of transgenic tomato plants. By western blot analysis, using specific antibodies, we determined that the VP2 and VP6 produced in plants have molecular weights similar to those found in native rotavirus. The plant-synthesized VP6 protein retained the capacity to form trimers. We were able to recover rotavirus virus-like particles from tomato fruit (i.e., tomatoes) by centrifugation on a sucrose cushion and to visualize them by electron microscopy. This result indicated that VP2/VP6 can self-assemble into virus-like particles (VLPs) in plant cells, even though only a small proportion of VP2/VP6 assembled into VLPs. To investigate immunogenicity, adult mice were immunized intraperitoneally (i.p.) three times with a protein extract from a transgenic tomatoes in adjuvant. We found that the transgenic tomato extract induced detectable levels of anti-rotavirus antibodies in serum; however, we did not determine the contribution of either the free rotavirus proteins or the VLPs to the induction of the antibody response. These results suggest the potential of plant-based rotavirus VLPs for the development of a vaccine against rotavirus infection.
Departamento de Ingeniería Genética, Centro de Investigación y de Estudios Avanzados del IPN, Irapuato, México.
Sergio
S
Saldaña
Fernando
F
Esquivel Guadarrama
Teresa De Jesús
Tde J
Olivera Flores
Nancy
N
Arias
Susana
S
López
Carlos
C
Arias
Roberto
R
Ruiz-Medrano
Hugh
H
Mason
Tsafrir
T
Mor
Liz
L
Richter
Charles J
CJ
Arntzen
Miguel A
MA
Gómez Lim
D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D000956:Antigens, Viral / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D036022:Capsid Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D005638:Fruit / Q000276:immunology / Q000378:metabolism / Q000821:virology; D015870:Gene Expression; D018551:Solanum lycopersicum / Q000276:immunology* / Q000378:metabolism / Q000821:virology*; D051379:Mice; D008807:Mice, Inbred BALB C; D030821:Plants, Genetically Modified; D012401:Rotavirus / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism*
D000914:Antibodies, Viral; D000956:Antigens, Viral; D036022:Capsid Proteins; C442545:VP2 protein, Rotavirus; C061332:VP6 protein, Rotavirus