Experimental studies using OMV in a new platform of SARS-CoV-2 vaccines

Although COVID-19 vaccines have recently been approved for emergency use, search for new vaccines are still urgent, since the access of the countries, especially the poorest, to the vaccines, has shown to be slower than the necessary to rapidly control the pandemic. We proposed a novel platform for vaccine using recombinant receptor binding domain (rRBD) from Sars-Cov-2 spike protein and Neisseria meningitidis outer membrane vesicles (OMVs). The antigen preparation produced a humoral and cellular immune response. Taken together our findings suggest a good immunostimulatory patter in response to immunization with rRBD plus N. meningitidis OMV.

Zika virus serological diagnosis: commercial tests and monoclonal antibodies as tools

Zika virus (ZIKV), an emerging arthropod-borne virus (arbovirus) of the Flaviviridae family, is a current issue worldwide, particularly because of the congenital and neurological syndromes associated with infection by this virus. As the initial clinical symptoms of all diseases caused by this group are very similar, clinical diagnosis is difficult. Furthermore, laboratory diagnostic efforts have failed to identify specific and accurate tests for each virus of the Flaviviridae family due to the cross-reactivity of these viruses in serum samples. This situation has resulted in underreporting of the diseases caused by flaviviruses. However, many companies developed commercial diagnostic tests after the recent ZIKV outbreak. Moreover, health regulatory agencies have approved different commercial tests to extend the monitoring of ZIKV infections. Considering that a specific and sensitive diagnostic method for estimating risk and evaluating ZIKV propagation is still needed, this review aims to provide an update of the main commercially approved serological diagnostics test by the US Food and Drug Administration (FDA) and Brazilian National Health Surveillance Agency (ANVISA). Additionally, we present the technologies used for monoclonal antibody production as a tool for the development of diagnostic tests and applications of these antibodies in detecting ZIKV infections worldwide.(AU)

Avaliação de anticorpos monoclonais como marcadores diferenciais de meningites bacterianas e virais por meio de técnica imuno-histoquímica / Investigation on the monoclonal antibodies as differential markers for viral and bacterial meningitis by means of immnunohistochemistry technique

Desde 1996, o Laboratório de Anticorpos Monoclonais, Antígenos e Adjuvantes - Centro de Imunologia do Instituto Adolfo Lutz (CI-IAL) tem desenvolvido trabalhos na caracterização antigênica de cepas de Neisseria meningitidis utilizando-se painel de anticorpos monoclonais(AcMo) pré-estabelecido, e produção de novos monoclonais para a análise de cepas com perfis desconhecidos. AcMo foram obtidos das diferentes fusões realizadas no laboratórioutilizando-se células esplênicas e linfonodos poplíteos. Dois hibridomas murinos secretores de AcMo anti-N. meningitidis produzidos e caracterizados no CI-IAL têm sido avaliados por meio de estudo imuno-histoquímico (IHQ) no Centro de Patologia-Laboratório de Imunohistoquímica-IAL. Com a padronização da reação, estabeleceu-se um protocolo para efetuar apesquisa de antígenos de N. meningitidis por IHQ. Houve melhoria no diagnóstico histopatológicoda meningite meningocócica, sobretudo em situações em que não há confirmação da presença do microorganismo por técnicas biomoleculares, como PCR, utilizando-se AcMo específicos para antígenos de diferentes sorogrupos, sorotipos e subtipos de N. meningitidis. O resultado obtido nos primeiros testes mostrou-se promissor, e os dois AcMo demonstraram excelentesresultados. Não houve reatividade cruzada com meningite viral, S. pneumoniae, Rickettsia ou rubéola. Nos próximos estudos, é fundamental ampliar número de amostras, incluindo-se aquelas coletadas de pacientes com meningites meningocócicas e de indivíduos infectados com outros agentes patogênicos.

Since 1996, the Laboratory of Monoclonal Antibodies, Antigens and Adjuvants - Immunology Center of the Adolfo Lutz Institute (CI-IAL) has been developing works on the antigenic characterization of strains of Neisseria meningitidis using pre-established panel of monoclonal antibodies (AcMo) And production of new monoclonals for the analysis of strains with unknown profiles. AcMo were obtained from the different fusions performed in the laboratory using splenic and popliteal lymph nodes. Two murine hybridomas secreting anti-N mAb. Meningitidis produced and characterized in CI-IAL have been evaluated by means of an immunohistochemical study (IHC) at the Center for Pathology-Laboratory of Immunohistochemistry-IAL. With the standardization of the reaction, a protocol was established to carry out research of antigens of N. meningitidis by IHC. There was improvement in the histopathological diagnosis of meningococcal meningitis, especially in situations where there is no confirmation of the presence of the microorganism by biomolecular techniques, such as PCR, using specific mAbs specific for antigens of different serogroups, serotypes and subtypes of N. meningitidis. The results obtained in the first tests proved to be promising, and the two MAbs demonstrated excellent results. There was no cross reactivity with viral meningitis, S. pneumoniae, Rickettsia or rubella. In the next studies, it is essential to expand the number of samples, including those collected from patients with meningococcal meningitis and from individuals infected with other pathogens.