PATRICK JACK SPENCER

Resumo

Possui graduação em Ciências Biológicas pela Universidade Presbiteriana Mackenzie (1991), mestrado em Tecnologia Nuclear pela Universidade de São Paulo (1995) e doutorado em Tecnologia Nuclear pela Universidade de São Paulo (2000) tendo sido bolsista sandwich no US Army Medical Research Institute for Infeccious Diseases (98-99). É responsável pelo Biotério de criação e manutenção de animais de laboratório do IPEN. Tem experiência na área de Bioquímica, com ênfase em Proteínas, atuando principalmente nos seguintes temas: veneno, proteínas, bothrops, irradiação e miotoxina.(Texto extraído do Currículo Lattes em 22 dez. 2021)

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  • Artigo IPEN-doc 27822
    Characterization and evaluation of the enzymatic activity of tetanus toxin submitted to cobalt-60 gamma radiation
    2021 - SARTORI, GISELLE P.; COSTA, ANDREA da; MACARINI, FERNANDO L. dos S.; MARIANO, DOUGLAS O.C.; PIMENTA, DANIEL C.; SPENCER, PATRICK J.; NALI, LUIZ H. da S.; GALISTEO JUNIOR, ANDRES J.
    Background Tetanus toxin blocks the release of the inhibitory neurotransmitters in the central nervous system and causes tetanus and its main form of prevention is through vaccination. The vaccine is produced by inactivation of tetanus toxin with formaldehyde, which may cause side effects. An alternative way is the use of ionizing radiation for inactivation of the toxin and also to improve the potential immunogenic response and to reduce the post-vaccination side effects. Therefore, the aim of this study was to characterize the tetanus toxin structure after different doses of ionizing radiation of 60Co. Methods Irradiated and native tetanus toxin was characterized by SDS PAGE in reducing and non-reducing conditions and MALD-TOF. Enzymatic activity was measured by FRET substrate. Also, antigenic properties were assessed by ELISA and Western Blot data. Results Characterization analysis revealed gradual modification on the tetanus toxin structure according to doses increase. Also, fragmentation and possible aggregations of the protein fragments were observed in higher doses. In the analysis of peptide preservation by enzymatic digestion and mass spectrometry, there was a slight modification in the identification up to the dose of 4 kGy. At subsequent doses, peptide identification was minimal. The analysis of the enzymatic activity by fluorescence showed 35 % attenuation in the activity even at higher doses. In the antigenic evaluation, anti-tetanus toxin antibodies were detected against the irradiated toxins at the different doses, with a gradual decrease as the dose increased, but remaining at satisfactory levels. Conclusion Ionizing radiation promoted structural changes in the tetanus toxin such as fragmentation and/or aggregation and attenuation of enzymatic activity as the dose increased, but antigenic recognition of the toxin remained at good levels indicating its possible use as an immunogen. However, studies of enzymatic activity of tetanus toxin irradiated with doses above 8 kGy should be further analyzed.
  • Artigo IPEN-doc 27224
    Paratrygon aiereba irradiated anti-mucus serum reduce edematogenic activity induced in experimental model
    2020 - THOMAZI, GABRIELA O.C.; COSTA, ANDREA da; RODRIGUES, JAQUELINE P.; ALVES, GLAUCIE J.; PREZOTTO NETO, JOSE P.; TURIBIO, THOMPSON de O.; ROCHA, ANDRE M.; AIRES, RAQUEL da S.; SEIBERT, CARLA S.; SPENCER, PATRICK J.; GALISTEO JUNIOR, ANDRES J.; ANDRADE JUNIOR, HEITOR F. de; NASCIMENTO, NANCI do
    Accidents by freshwater stingrays are common in northern Brazil, there is no specific therapy for high morbidity and local tissue destruction. The irradiation of venoms and toxins by ionizing radiation has been used to produce appropriate immunogens for the production of antisera. We planned to study the efficacy of stinging mucus irradiation in the production of antisera, with serum neutralization assays of edematogenic activity and quantification of cytokines performed in animal models of immunization with native and irradiated mucus of Paratrygon aiereba, a large freshwater stingray. Antiserum potency and its cross-reactivity with mucus from other freshwater stingrays were detected by ELISA. Immunization models demonstrated the ability to stimulate a strong humoral response with elevated levels of serum IgG detectable by ELISA, and both native and irradiated mucus were immunogenic and capable of recognizing mucus proteins from other freshwater neotropical stingrays. Mucus P. aiereba causes cellular and humoral adaptive immune responses in cells of immunized mice producing antibodies and cytokines such as TNF-α, IL-6 and IL-17. Rabbit antisera immunized with mucus from P. aiereba irradiated at 2 kGy showed a significant reduction of mucus-induced edematogenic activity in mice. Our data suggest that the use of antisera against freshwater stingray mucus show the possibility of specific therapy for these accidents.
  • Artigo IPEN-doc 26265
    Characterization and evaluation of the enzymatic activity of tetanus toxin submitted to gamma radiation by Cobalt 60
    2019 - SARTORI, GISELLE P.; COSTA, ANDREA; MACARINI, FERNANDA L.S.; MARIANO, DOUGLAS O.C.; PIMENTA, DANIEL C.; SPENCER, PATRICK J.; GALISTEO JUNIOR, ANDRES J.
    Tetanus is a neurological disease which blocks the inhibitory neurotransmitters liberation. Also treatment does not cure the disease, and its main form of prevention is through vaccination. The vaccine is produced by the inactivation of tetanic toxin (TeNT) with formaldehyde, which may cause side effects. An alternative way is the use of ionizing radiation for inactivation of the toxin and also to improve the potential immunogenic response and to reduce the pos-vaccination side effects. Therefore, the aim of this study was to characterize the TeNT structure after different doses of ionizing radiation of Cobalt 60, and also to assess the enzymatic activity after the radiation. SDS PAGE and MALDI-TOF analysis revealed gradual modification on the TeNT structure according to doses increase. Also, fragmentation and possible aggregations of the protein fragments were observed in higher doses. In the analysis of peptide preservation by enzymatic digestion and mass spectrometry, there was a slight modification in the recognition up to the dose of 4 kGy at subsequent doses, recognition was minimal. The analysis of the enzymatic activity by fluorescence showed a 35 % attenuation in the activity even at higher doses. In the antigenic evaluation performed by ELISA and Western Blot, anti-TeNT antibodies were detected against the irradiated toxins at the different doses, with a gradual decrease as the dose increased, but remaining at satisfactory levels, indicating the possibility of possible use as an immunogen, however, studies of enzymatic activity on higher should be further analyzed.
  • Resumo IPEN-doc 22122
    Estudo dos efeitos da radiação gama de sup(Co na bothropstoxina 1 do veneno de Bothrops jararacussu
    2007 - SILVA, DIEGO de A.; SILVA, MURILO C. da; SPENCER, PATRICK J.
  • Artigo IPEN-doc 21107
    Comparative nephrotoxicity of native or Co-60 gamma rays irradiated crotoxin in mice
    2015 - ROCHA, ANDRE M.; ROCHA, JOSEFA M.N.; MAGALHAES FILHO, ASTERIO S.; ALVES, GLAUCIE J.; AIRES, RAQUEL da S.; TURIBIO, THOMPSON O.; THOMAZI, GABRIELA O.C.; SPENCER, PATRICK J.; NASCIMENTO, NANCI do
  • Artigo IPEN-doc 20886
    New insights into the structural characteristics of irradiated crotamine
    2015 - OLIVEIRA, KARINA C.; SPENCER, PATRICK J.; FERREIRA JUNIOR, RUI S.; NASCIMENTO, NANCI
  • Capítulo IPEN-doc 02923
    Comparative studies of antisera against different toxins
    1996 - NASCIMENTO, N.; SPENCER, P.J.; PAULA, R.A.; ANDRADE JUNIOR, H.F.; ROGERO, J.R.
  • Resumo IPEN-doc 04676
    Structural and biological alterations of crotoxin following irradiation in the presence of thiol groups
    1997 - NASCIMENTO, N.; ANDRIANI, E.P.; SPENCER, P.J.; ROGERO, J.R.
  • Resumo IPEN-doc 05091
  • Resumo IPEN-doc 04685
    Biochemical and immunological characterization of the main products of crotoxin irradiation
    1996 - NASCIMENTO, N.; CLISSA, P.B.; SPENCER, P.J.; ANDRADE JUNIOR, H.F.; KAISER, I.I.; ROGERO, J.R.