Recombinant CP40 from Corynebacterium pseudotuberculosis confers protection in mice after challenge with a virulent strain.

BACKGROUND: Caseous Lymphadenitis (CLA) is a contagious, infectious, chronic disease caused by Corynebacterium pseudotuberculosis, which affects mainly sheep and goats. The clinical prevalence of CLA in Brazil is 30%, resulting in decreased milk production, weight loss, and unusable meat and leather. Prophylaxis is based on vaccination; however, current vaccinations do not offer effective protection against the infection, which makes the development of a new vaccine essential to control this disease. EXPERIMENTAL APPROACH: Here, we developed a recombinant vaccine based on CP40 protein (rCP40) combined with an adjuvant (Freund's complete adjuvant or saponin) and evaluated its efficacy in a murine model of CLA. Female BALB/c mice were used in an immunization assay. KEY RESULTS: rCP40 induced high levels of IgG2a and IgG2b antibodies. After challenge with a virulent strain of C. pseudotuberculosis C57 (10(4)CFU/mL), the levels of IgG2a and IgG2b were sustained, indicating a Th1 response. The groups immunized with rCP40 protein (GES and GEF groups) showed 100% protection and was statistically significant in the GES and GEF groups (p<0.037 and p<0.0952, respectively). CONCLUSIONS: The results indicated the recombinant protein CP40 induced an specific immune response in mice that was able to afford protection after challenge, regardless the adjuvant used in the formulation.

Corynebacterium pseudotuberculosis cp09 mutant and cp40 recombinant protein partially protect mice against caseous lymphadenitis.

BACKGROUND: Caseous lymphadenitis (CLA) is an infectious disease that affects small ruminants and is caused by Corynebacterium pseudotuberculosis. This disease is responsible for high economic losses due to condemnation and trim of infected carcasses, decreased leather and wool yield, loss of sales of breeding stock and deaths from internal involvement. Treatment is costly and ineffective; the most cost-effective strategy is timely immunisation. Various vaccine strategies have been tested, and recombinant vaccines are a promising alternative. Thus, in this study, different vaccine formulations using a recombinant protein (rCP40) and the CP09 live recombinant strain were evaluated. Five groups of 10 mice each were immunised with saline (G1), rCP40 (G2), CP09 (G3), a combination of CP09 and rCP40 (G4) and a heterologous prime-boost strategy (G5). Mice received two immunisations within 15 days. On day 30 after primary immunisation, all groups were challenged with a C. pseudotuberculosis virulent strain. Mice were monitored and mortality was recorded for 30 days after challenge. RESULTS: The G2, G4 and G5 groups showed high levels of IgG1 and IgG2a; G2 presented significant IgG2a production after virulent challenge in the absence of IgG1 and IgG3 induction. Thirty days after challenge, the mice survival rates were 20 (G1), 90 (G2), 50 (G3), 70 (G4) and 60% (G5). CONCLUSIONS: rCP40 is a promising target in the development of vaccines against caseous lymphadenitis.

Heterozigose para hemoglobinopatias em doadores de sangue do Centro de Hemoterapia de Sergipe / Heterozigosity to hemoglobinopathies in blood donors from the Hemotherapy Center in Sergipe, NE-Brazil

As hemoglobinopatias, distúrbios geneticamente determinados da hemoglobina (Hb) humana, estão presentes com freqüência elevada em várias partes do mundo, sendo que no Brasil as Hb anormais S e C são as mais prevalentes. Com o objetivo de identificar a presença de portadores saudáveis de genes para hemoglobinopatias entre doadores de sangue do Centro de Hemoterapia do Estado de Sergipe (Hemose), foram analisadas 1.345 amostras de doadores de sangue. Em todas as amostras foram realizados eritrograma automatizado e eletroforese de hemoglobina em acetato de celulose utilizando-se tampão Tris-EDTA-Borato pH 8,6. As amostras que apresentaram hemoglobinas anormais foram submetidas a teste de falcização, teste de solubilidade e Cromatografia Líquida de Alta Performance (HPLC). Foram identificadas 76 amostras com hemoglobinas anormais (5,6 por cento), das quais 55 (4,1 por cento) com traço falciforme (Hb AS), 19 (1,4 por cento) com Hb AC, uma com Hb AD e outra sugestiva de beta-talassemia. Os resultados encontrados demonstram a necessidade de implantação da triagem para hemoglobinopatias entre doadores de sangue, pois desta maneira o receptor de sangue é beneficiado com produto de melhor qualidade, e o doador com a identificação de uma alteração genética que pode vir a se manifestar em seus descendentes.

Hemoglobinopathies are genetically determined disorders that present in significant high frequencies in certain parts of the world. Despite of the existence of hundreds of known hereditary hemoglobinopathies, Brazilian studies have demonstrated that abnormal hemoglobins S and C are the most prevalent. With the objective of identifying the profile of hemoglobinopathies of blood donors at the Hemotherapy Center in the State of Sergipe (Hemose), 1345 samples of blood were analyzed. Initially automatic blood testing and electrophoreses in cellulose acetate using a Tris-EDTA-Borate buffer at pH 8.6 were carried out for all samples. Samples that presented with abnormal hemoglobins were submitted to testing for the sickle cell trait, solubility test and by High Performance Liquid Chromatography. Seventy-six samples (5.6 percent) with abnormal hemoglobins were identified, 55 (4.1 percent) of which had the sickle cell trait (Hb AS), 19 (1.4 percent) had Hb AC, 1 (0.1 percent) had Hb AD and 1 (0.1 percent) was suggestive for beta- thalassaemia. The results demonstrate a necessity for the implantation of screening of hemoglobinopathies in blood donors, so that blood recipients benefit from good quality blood and donors from the diagnoses of genetic alterations that may be prevented in descendants.