Genetic stability ofBrucella abortusS19 and RB51 vaccine strains by multiplelocusvariable number tandem repeat analysis (MLVA16)

• Published in: Vaccine 2013-10, Vol.31 (42), p.4856
• Main Authors: Dorneles, Elaine Maria Seles, de Faria, Ana Paula Paiva, Pauletti, Rebeca Barbosa, Santana, Jordana Almeida, Caldeira, George Afonso Vítor, Heinemann, Marcos Bryan, Titze-de-Almeida, Ricardo, Lage, Andrey Pereira
• Format: Article
• Language: English
• Subjects: Animal vaccines; Bacteriology; Brucellosis; Deoxyribonucleic acid; DNA; Genetic diversity; Genotypes; Glycerol; Immunization; Laboratories; Manufacturers; Quality control; Vaccines
• ISSN: 0264-410X; 1873-2518
• DOI: 10.1016/j.vaccine.2013.07.063

The aims of the present study were (i) to assess thein vitrogenetic stability of S19 and RB51Brucella abortusvaccines strains and (ii) to evaluate the ability of multiple-locusvariable-number tandem repeat (VNTR) analysis (MLVA) as a tool to be used in the quality control of live vaccines against brucellosis. Sixty-three batches of commercial S19 (n=53) and RB51 (n=10) vaccines, produced between 2006 and 2009, were used in this study. S19 and RB51 vaccines were obtained from, respectively, seven and two different manufacturers. Tenin vitroserial passages were performed on reference strains and on selected batches of commercial vaccines. All batches, reference strains and strains of serial passages were typed by the MLVA16. The results demonstrated thatB. abortusS19 and RB51 vaccine strains are genetically stable and very homogeneous in their respective groups. Anyway, batches of S19 from one manufacturer and batches of RB51 from another presented genotypes distincts from the reference vaccine strains. In both cases, differences were found onlocusBruce07, which had addition of one repeat unit in the case of S19 batches and the deletion of one repeat unit in the case of RB51 batches. In summary, MLVA16 proved to be a molecular tool capable of discriminating small genomic variations and should be included inin vitroofficial tests.