Outer membrane vesicle ofNeisseria meningitidis serogroup B as an adjuvant to induce specific antibody response against the lipopolysaccharide ofBrucella abortus S99

Abstract

Brucellosis is a worldwide zoonosis and represents one of the most important public health problems in many countries, especially around the Mediterranean basin, Middle East, India and Central and South America. Currently subunit vaccines are being considered to develop effective vaccines for human which has been evidenced by vaccines currently available against the infections such as meningococcal diseases and influenza .The application of new adjuvants of microbial origins is also underway to design subunit vaccines promoting the immune responses to the antigenic determinant(s) of the vaccine. In order to explore the efficacy of Brucella abortus lipopolysaccharide (LPS) combined with different adjuvants and proteins (as a vaccine candidate) in the induction of immune response as an effective and long-lasting immunity against Brucella, we evaluated the outer membrane vesicle of Neisseria meningitidis serogroup B (GBMOMV) as a subcutaneous adjuvant and a part of a brucellosis candidate vaccine to induce high titres of specific anti-Brucella abortus S99 LPS in animal model (mice). The obtained results were compared with complete and incomplete Freund's adjuvants (CFA and IFA). LPS+GBMOMV was the most immunogenic compound that stimulated following the first injection an increase in IgG titre of about 3.90, 3.18 and 1.58 fold higher than that produced against LPS, LPS+IFA and LPS+CFA, respectively. The highest anti-LPS IgG titre was detected two weeks after the third injection (the day 42) of LPS+GBMOMV. Purified GBMOMV can be considered as a safe subcutaneous adjuvant and a part of a candidate vaccine when combined with lipopolysaccharide of Brucella abortus S99.

New insight into the application of outer membrane vesicles of Gram-negative bacteria

“…Several studies have reported the adjuvant properties of OMVs in the field of vaccine research, namely in cancer vaccines, brucellosis vaccine, tuberculosis (TB) vaccine, meningococcal vaccine, Influenza virus vaccine, hepatitis B vaccine and human immunodeficiency virus (HIV) vaccine. [12,13,21,[23][24][25]. Most of the classic and new adjuvants cause local and systemic hypersensitivity reactions and are not licensed for human use.…”

“…In addition, the adjuvant properties of OMV-derived particles have been demonstrated for potential cancer vaccines [25,27]. Interesting studies in the field of brucellosis subunit vaccines have been carried out by Bhattacharjee et al and Sharifat et al [23,28] which have evaluated group B OMPs (GB-OMV). Brucella melitensis strain 16M LPS non-covalent complex to elicit the immunity against brucellosis in mice.…”

“…Sharifat and colleagues have also evaluated and reported the OMVs of N. meningitidis serogroup B as a potent subcutaneous adjuvant and a part of a candidate vaccine against brucellosis which have been shown to induce high titers of specific anti-B. abortus S99 LPS in an animal model [21,23,28].…”

Vesículas de Membrana Externa (OMV) de >i<Neisseria lactamia>/i<: Processo de Obtenção e Avaliação do Potencial Adjuvante

“…OMV de Neisseria meningitidis do sorogrupo B é um dos componentes de origem microbiana mais estudada no que diz respeito à aplicação como adjuvante (Sharifat Salmani et al, 2009;Moshiri et al, 2012). A propriedade adjuvante de OMV proveniente deste e de outros microrganismos vem sendo demonstrada em diversos estudos de desenvolvimento de vacinas.…”

“…A propriedade adjuvante de OMV proveniente deste e de outros microrganismos vem sendo demonstrada em diversos estudos de desenvolvimento de vacinas. Dentre os principais destacam-se vacinas para a doença causada pelo vírus da influenza (Sharifat Salmani et al, 2009), vírus sincicial respiratório (Etchart et al, 2006), hepatite B (Sardiñas et al, 2006), brucelose (Sharifat Salmani et al, 2009), vírus da herpes genital (Del Campo et al, 2010), para a doença meningocócica tipo B (Tamargo et al, 2013), HIV (Aghasadeghi et al, 2011) e, mais recentemente, têm-se discutido sua aplicação como adjuvante para diferentes tipos de vacinas de câncer (Gujrati e Jon, 2014 Por outro lado, as OMV têm propriedades para apresentar antígenos, além de propriedades adjuvantes, sendo uma estrutura com alto potencial para ser, o que hoje autores denominam, uma plataforma vacinal completa (Gerritzen et al, 2017).…”