PESQUISA VETERINÁRIA BRASILEIRA

Abstract in English:

ABSTRACT.- Silva Júnior A., Castro L.A., Chiarelli Neto O., Silva F.M.F., Vidigal P.M.P., Moraes M.P. & Almeida M.R. 2009. Development and evaluation of a recombinant DNA vaccine candidate expressing porcine circovirus 2 structural protein. Pesquisa Veterinária Brasileira 29(1):76-82. Laboratório de Infectologia Molecular Animal, Instituto de Biotecnologia Aplicada à Agropecuária, Universidade Federal de Viçosa, Av. PH Rolfs s/n, Campus Universitário, Viçosa, MG 36570-000, Brazil. E-mail: marcia@ufv.br Porcine circovirus 2 (PCV2) is generally associated with the porcine circovirosis syndrome, which is considered an important disease of swine and has potentially serious economic impact on the swine industry worldwide. This article describes the construction of a recombinant plasmid expressing the PCV2 structural protein and the evaluation of cellular and humoral immune responses produced by this recombinant vaccine in BALB/c mice. The vaccine candidate was obtained and analyzed in vivo, in an effort to determine the ability to induce a specific immune response in mice. DNA was extracted from a Brazilian PCV2 isolate and the gene coding for Cap protein was amplified by PCR and inserted into an expression plasmid. Groups of BALB/c mice were inoculated intra-muscularly and intradermally in a 15-day interval, with 100 µg and 50 µg of the vaccine construct, respectively. Another group was inoculated intramuscularly with 100 µg of empty plasmid, corresponding to the control group. Seroconversion and cellular response in BALB/c mice were compared and used for vaccine evaluation. Seroconversion was analyzed by ELISA. After a series of 3 immunizations the spleen cells of the immunized animals were used to perform lymphocyte proliferation assays. Seroconversion to PCV2 was detected by ELISA in the animals inoculated with the vaccine construct when compared with control groups. Lymphocyte proliferation assays showed a stronger cell proliferation in the inoculated animals compared with the control group. Thus, the vaccine candidate construct demonstrated to be able to induce both humoral and cellular responses in inoculated mice.

• PCV2 DNA vaccine porcine circovirosis

Abstract in Portuguese:

ABSTRACT.- Silva Júnior A., Castro L.A., Chiarelli Neto O., Silva F.M.F., Vidigal P.M.P., Moraes M.P. & Almeida M.R. 2009. Development and evaluation of a recombinant DNA vaccine candidate expressing porcine circovirus 2 structural protein. Pesquisa Veterinária Brasileira 29(1):76-82. Laboratório de Infectologia Molecular Animal, Instituto de Biotecnologia Aplicada à Agropecuária, Universidade Federal de Viçosa, Av. PH Rolfs s/n, Campus Universitário, Viçosa, MG 36570-000, Brazil. E-mail: marcia@ufv.br Porcine circovirus 2 (PCV2) is generally associated with the porcine circovirosis syndrome, which is considered an important disease of swine and has potentially serious economic impact on the swine industry worldwide. This article describes the construction of a recombinant plasmid expressing the PCV2 structural protein and the evaluation of cellular and humoral immune responses produced by this recombinant vaccine in BALB/c mice. The vaccine candidate was obtained and analyzed in vivo, in an effort to determine the ability to induce a specific immune response in mice. DNA was extracted from a Brazilian PCV2 isolate and the gene coding for Cap protein was amplified by PCR and inserted into an expression plasmid. Groups of BALB/c mice were inoculated intra-muscularly and intradermally in a 15-day interval, with 100 µg and 50 µg of the vaccine construct, respectively. Another group was inoculated intramuscularly with 100 µg of empty plasmid, corresponding to the control group. Seroconversion and cellular response in BALB/c mice were compared and used for vaccine evaluation. Seroconversion was analyzed by ELISA. After a series of 3 immunizations the spleen cells of the immunized animals were used to perform lymphocyte proliferation assays. Seroconversion to PCV2 was detected by ELISA in the animals inoculated with the vaccine construct when compared with control groups. Lymphocyte proliferation assays showed a stronger cell proliferation in the inoculated animals compared with the control group. Thus, the vaccine candidate construct demonstrated to be able to induce both humoral and cellular responses in inoculated mice.

Abstract in English:

Aguirre J.I., Gomar M.S., Igal, S., Quiroga M.A., Portiansky E.L & Gimeno E.J. 2005. Bone changes caused by experimental Solanum malacoxylon poisoning in rabbits. [Alterações ósseas causadas na intoxicação experimental por Solanum malacoxylon em coelhos.] Pesquisa Veterinária Brasileira 25(1):34-38. Institute of Pathology “Prof. Dr. Bernardo Epstein”, School of Veterinary Sciences, National University of La Plata, P.O.Box 296, (1900) La Plata, Argentina. E-mail: ejgimeno@fcv.unlp.edu.ar The aim of this study was to describe the bone changes observed after a daily oral administration of the calcinogenic plant Solanum malacoxylon (syn. S. glaucophyllum) (Sm) during 9 days. The Sm-poisoned rabbits had an increase of bone resorption in the endosteal surface of the cortical zone and also in the surface covered by osteoblasts of the primary and secondary spongiosa of the trabecular bone compartment. Moreover, the epiphyseal growth plates in long bones appeared narrower than in the control rabbits, with reduction of the proliferative and hyperthrophic chondrocyte zones. The electron microscopic study revealed a significant decrease of proteoglycans in the hyperthrophic chondrocyte zone evidenced by a significant reduction of rutenium red positive granules in the poisoned rabbit. Altogether, these data suggest that cell differentiation may play a pivotal role in the pathogenesis of Sm-induced bone lesions.

• Solanum malacoxylon S. glaucophyllum calcinogenic plant rabbit bone tissue growth plate.

Abstract in Portuguese:

Aguirre J.I., Gomar M.S., Igal, S., Quiroga M.A., Portiansky E.L & Gimeno E.J. 2005. Bone changes caused by experimental Solanum malacoxylon poisoning in rabbits. [Alterações ósseas causadas na intoxicação experimental por Solanum malacoxylon em coelhos.] Pesquisa Veterinária Brasileira 25(1):34-38. Institute of Pathology “Prof. Dr. Bernardo Epstein”, School of Veterinary Sciences, National University of La Plata, P.O.Box 296, (1900) La Plata, Argentina. E-mail: ejgimeno@fcv.unlp.edu.ar The aim of this study was to describe the bone changes observed after a daily oral administration of the calcinogenic plant Solanum malacoxylon (syn. S. glaucophyllum) (Sm) during 9 days. The Sm-poisoned rabbits had an increase of bone resorption in the endosteal surface of the cortical zone and also in the surface covered by osteoblasts of the primary and secondary spongiosa of the trabecular bone compartment. Moreover, the epiphyseal growth plates in long bones appeared narrower than in the control rabbits, with reduction of the proliferative and hyperthrophic chondrocyte zones. The electron microscopic study revealed a significant decrease of proteoglycans in the hyperthrophic chondrocyte zone evidenced by a significant reduction of rutenium red positive granules in the poisoned rabbit. Altogether, these data suggest that cell differentiation may play a pivotal role in the pathogenesis of Sm-induced bone lesions.