Usos de la levadura Pichia pastoris en la producción de proteínas recombinantes / Uses of Pichia pastoris yeast in the production of recombinant proteins

La levadura metilotrófica Pichia pastoris (clasificada actualmente como Komagataella phaffii) es una de las más importantes para la producción de proteínas heterólogas. En el trabajo se presenta un análisis de las principales características que se ponen de manifiesto en la expresión de proteínas recombinantes expresadas en este microorganismo. Se describen las cepas disponibles para la transformación y producción de proteínas recombinantes expresadas en Pichia pastoris, los principales vectores comerciales para la expresión, los promotores más eficientes, los marcadores seleccionables, la señal de secreción, los métodos usados en las transformaciones genéticas y los patrones de glicosilación que se presentan. Se brindan recomendaciones generales acerca de los parámetros de bioprocesos como la composición del medio, el pH, la temperatura, la velocidad de aireación, la inducción y las estrategias de alimentación para alcanzar altos valores de productividad. Se presentan los resultados de las aplicaciones de Pichia pastoris en la producción de dos vacunas en Cuba, la vacuna contra la hepatitis B y la vacuna para el control de la garrapata(AU)

Pichia pastoris metylotrofic yeast (currently classified as Komagataella phaffii) is one of the most important yeast for the production of heterologous proteins. The work presents an analysis of the main characteristics that are marked in the production of recombinant proteins expressed in Pichia pastoris. It describes the strains available for the transformation and production of recombinant proteins expressed in P. pastoris, the main commercial vectors for expression, the most efficient promoters, selectable markers, the secretion signal, the methods used in genetic transformations and glycosylation patterns that occur. General recommendations are provided on bioprocess parameters such as media composition, pH, temperature, aeration velocity, induction, and feeding strategies to achieve high productivity values. The results of Pichia pastoris applications for the production of two vaccines in Cuba, the hepatitis B vaccine and the tick control vaccine are shown(AU)

Seroprotección para virus de hepatitis B en estudiantes universitarios de atención prehospitalaria en Cali, Colombia / Seroprotection for hepatitis B virus in university students of prehospital care in Cali, Colombia

Introducción: El personal de salud se encuentra expuesto a contraer enfermedades infecto contagiosas en el ejercicio de su labor, una de ellas es la hepatitis B. Los estudiantes de atención prehospitalaria no se encuentran exentos de sufrir esta enfermedad, sobre todo por el contexto de las emergencias y desastres donde se desenvuelven. Objetivo: Determinar la prevalencia de seroprotección para el virus de hepatitis B en estudiantes de atención prehospitalaria en una universidad en Colombia. Métodos: Estudio descriptivo de corte transversal realizado a estudiantes de atención prehospitalaria en el periodo febrero-junio de 2017. No se utilizó ninguna técnica de muestreo porque se incluyó la totalidad de los estudiantes en práctica. Se aplicó un cuestionario con preguntas de datos sociodemográficos, registro del esquema de vacunación para hepatitis B y el resultado de los anticuerpos (Anti-HBs). Para el análisis estadístico se utilizó Microsoft Excel 2010, se construyeron estadísticas descriptivas. Las variables numéricas se describieron con base en medidas de tendencia central y variabilidad, las variables categóricas se describieron con base en prevalencias y distribuciones porcentuales. Resultados: En la caracterización de los 103 estudiantes evaluados se encontró que el 98 por ciento obtuvo títulos de anticuerpos (Anti-HBs) mayores a 10 UI/ml, considerándose como reactivos a las dosis de las vacunas, alcanzando títulos protectores. Sin embargo, el 93 por ciento no cumplió con el esquema de vacunación establecido. Conclusiones: Los resultados obtenidos evidencian la efectividad de las dosis aplicadas de vacuna para el virus de hepatitis B para obtener los títulos de anticuerpos a estudiantes de atención prehospitalaria en una universidad en Colombia. Pero existen incumplimientos en los tiempos recomendados para la aplicación de cada una de las dosis y en el tiempo de toma de los títulos(AU)

Introduction: Health personnel are at risk of infectious diseases when doing their job. One of them is hepatitis B. Prehospital care students are not free from suffering this disease, especially due to the emergencies and disasters context in which they work. Objective: To determine the prevalence of seroprotection for the hepatitis B virus in prehospital care students at a university in Colombia. Methods: Descriptive cross-sectional study carried out on prehospital care students during the period February-June 2017. No sampling technique was used because all the students in practice were included. A questionnaire was applied with questions of social-demographic data, registration of the vaccination schedule for hepatitis B and result of (Anti-HBs) antibodies. For statistical analysis, Microsoft Excel 2010 was used and descriptive statistics were designed. Numerical variables were described based on measures of central tendency and variability, categorical variables were described based on prevalence and percentage distributions. Results: In the depiction of the 103 students who were evaluated, it was found that 98 percent obtained antibody titers (Anti-HBs) bigger than 10 IU / ml, being considered as reactive to the doses of the vaccines and getting protective titles. However, 93 percent did not fill the established vaccination schedule. Conclusions: It can be concluded that the results obtained show the effectiveness of the applied doses of vaccine for the hepatitis B virus to obtain antibody titers to prehospital care students at a university in Colombia. But there are breaches in the recommended times for the application of each of the doses and in the time of taking the antibody titers(AU)

Low completion rate of hepatitis B vaccination in female sex workers / Esquema incompleto de vacunación contra hepatitis B en mujeres profesionales del sexo / Baixa completude da vacina contra hepatite B em mulheres profissionais do sexo

ABSTRACT Objective: to assess predictive factors for noncompletion of the hepatitis B vaccination schedule in female sex workers in the city of Teresina, Northeastern Brazil. Method: 402 women were interviewed and, for those who did not wish to visit specialized sites, or did not know their hepatitis B vaccination status, the vaccine was offered at their workplaces. Bi- and multivariate analyses were performed to identify potential predictors for noncompletion of the vaccination schedule. Results: of the 284 women eligible for vaccination, 258 (90.8%) received the second dose, 157/258 (60.8%) and 68/258 (26.3%) received the second and third doses, respectively. Working at clubs and consuming illicit drugs were predictors for noncompletion of the vaccination schedule. Conclusion: the high acceptability of the vaccine's first dose, associated with low completion rates of the vaccination schedule in sex workers, shows the need for more persuasive strategies that go beyond offering the vaccine at their workplaces.

RESUMEN Objetivo: Evaluar factores predictores del no completamiento del esquema de vacunación contra la hepatitis B en mujeres que se prostituyen en Teresina, noreste de Brasil. Método: Fueron entrevistadas 402 mujeres. Para las que se negaron a ir a lugares especializados o desconocían su situación de vacunación contra la hepatitis B, la vacuna fue ofrecida en lugar de trabajo. Fueron efectuados análisis multivariados para identificar potenciales predictores del no completamiento del esquema de vacunación. Resultados: de las 284 mujeres elegibles para vacunación, 258 (90,8%) recibieron primera dosis, 157/258 (60,8%) y 68/258 (26,3%) recibieron segunda y tercera dosis. Trabajar en burdeles y consumir drogas fueron factores predictores de no completamiento del esquema (p<0,05). Conclusión: La elevada aceptación de la primera dosis, asociada al bajo completamiento del esquema de vacunación en profesionales del sexo, evidencia necesidad de una estrategia más persuasiva, más allá de la oferta de vacunación en el lugar de trabajo.

RESUMO Objetivo: avaliar fatores preditores de não completude do esquema vacinal contra hepatite B em mulheres que se prostituem em Teresina, Nordeste do Brasil. Método: Um total de 402 mulheres foi entrevistado e, para as que se negaram a irem a lugares especializados, ou desconheciam sua situação vacinal contra hepatite B, a vacina foi oferecida no local do trabalho. Análises bi e multivariadas foram realizadas para identificar potenciais preditores de não completude do esquema vacinal. Resultados: Das 284 mulheres elegíveis para vacinação, 258 (90,8%) receberam a primeira dose, 157/258 (60,8%) e 68/258 (26,3%) receberam a segunda e terceira doses. Trabalhar em boates e consumir drogas ilícitas foram preditores de não completude do esquema vacinal (p<0,05). Conclusão: A elevada aceitabilidade da primeira dose da vacina, associada à baixa completude do esquema vacinal em profissionais do sexo, evidencia a necessidade de estratégia mais persuasiva que vá além da oferta da vacina no local de trabalho.

Occult hepatitis B infection in Egyptian health care workers

We tested the frequency of occult hepatitis B infection [OBI] among Egyptian healthcare workers [HCWs]. We tested 132 HCWs for hepatitis B virus [HBV] DNA by nested polymerase chain reaction [PCR], and hepatitis C virus antibody [anti-HCV] by ELISA. HCV RNA was measured by nested PCR in anti-HCV-positive HCWs. HBV-DNA-positive HCWs were subjected to HBV genotyping. We included 132 HCWs who were negative for hepatitis B surface antigen and positive for hepatitis B core antibody [anti-HBc]. OBI was detected in 7 male HCWs, and HBV E genotype was detected in 3, HBV D in 2 and HBV D and E in 2. Two OBI-positive HCWs had a history of neonatal hepatitis B vaccination. Anti-HCV seropositivity was detected in 17 HCWs who were positive for anti-HBc; 15 of whom were positive for HCV RNA by nested PCR. HCV infection was confirmed by anti-HCV and HCV RNA in 1 of 7 HCWs with OBI. In conclusion, Egyptian HCWs have a significant rate of OBI and HBV E genotype is prevalent

Hepatitis B en Argentina. Situación actual y estrategia de vacunación universal para su control y eliminación / Hepatitis B in argentina. current situation and strategy of universal vaccination for control and elimination

El virus de la hepatitis B es el agente productor de una enfermedad con alta eficacia de transmisión por la vía sexual, vertical y parenteral. Si bien en la mayoría de los casos se trata de una infección aguda con recuperación espontánea y sin secuelas puede evolucionar con una forma fulminante o como hepatitis crónica. Dadas las dificultades para su tratamiento se considera que la mejor estrategia de control es la prevención a través de la inmunización. En Argentina la vacuna está incorporada al calendario nacional para los recién nacidos desde el año 2000 y recomendada para los adultos que integran los grupos de riesgo. Los datos de la vigilancia muestran la persistencia de casos en los mayores de 15 años siendo una de sus causas la dificultad en identificar a la población en riesgo para ser vacunada. Debido a esto el ProNaCEI formuló en 2012 la recomendación de vacunación universal para hepatitis B con el propósito de contribuir a la eliminación y control de la hepatitis B. Este artículo analiza la situación actual de la hepatitis B en Argentina y los fundamentos y de la estrategia de vacunación universal...

The hepatitis B virus is responsible for a disease with high efficiency by sexual transmission, vertical and parenterally. Its complications include fulminant and chronic hepatitis. Vaccination is the most effective prevention strategy. In Argentina the vaccine is incorporated into national schedule for infants and is recommended for adult members of risk groups. Monitoring data show the persistence of cases over 15 years old. One reason for this problem is the difficulty in identifying risk groups. In order to contribute to the elimination and control of hepatitis B ProNaCEI incorporated in July 2013 universal vaccination against hepatitis B. This article describes the current status of hepatitis B in Argentina and technical guidelines recommending universal vaccination is analyzed...

Recent trends in hepatitis B virus infection in the general Korean population

BACKGROUND/AIMS: Hepatitis B virus (HBV) is the major cause of chronic liver disease in Korea, but viral prevalence has decreased because of hepatitis B vaccination programs. In this study, we investigated longitudinal changes in HBV in fection in the general Korean population. METHODS: HBV surface antigen (hepatitis B surface antigen, HBsAg) seropositivity was assessed from the Korea National Health and Nutrition Examination Survey (I to V). In total, 50,140 subjects were tested for serum HBsAg positivity over a period of 12 years (1998 to 2010). RESULTS: The prevalence of HBsAg seropositivity decreased over the study period. The rates of HBsAg carriers were 4.61% in 1998, 4.60% in 2001, 3.69% in 2005, 3.01% in 2008, and 2.98% in 2010 (p 0.05). Neither gender nor socioeconomic status were associated with the decreased prevalence of HBsAg carriers. CONCLUSIONS: HBV infection has decreased in the Korean population since the advent of vaccination programs. However, the decrease is limited to the younger population, and viral persistence remains in the middle-aged and older population.

Prevention of Hepatitis B-Knowledge and Practices Among Medical Students.

Background: Hepatitis B is the major infectious disease of mankind. It is the most common cause of chronic hepatitis, liver cirrhosis and hepato-cellular carcinoma world wide .The health professionals are at the most risk. Vaccination against Hepatitis B can prevent this deadly disease. This survey was conducted to assess the knowledge and status of Hepatitis B vaccination among the medical students of B.J. Medical College, Ahmedabad. Methods: A cross-sectional study was conducted among 150 medical students of II, III/I and III/II year .Pre-tested questionnaire were administered to 50 students of each semester. Data was analyzed using SPSS version 16.0. Results: 86.7 % of the medical students had correct knowledge about Hepatitis B virus, though only 66 % of II year students knew about the virus. Majority of the medical students had correct knowledge regarding mode of transmission however, the knowledge was found to be less among II year students. Only 20% of the II year students had the correct knowledge regarding Post Exposure Prophylaxis for hepatitis B. 29.3% of the medical students were not vaccinated for Hepatitis B. Conclusion: The present study concludes that there is a lack of awareness among the medical students entering into the profession about Hepatitis B, its route of transmission and modes of prevention .Similarly all the students were not vaccinated against Hepatitis B, which makes them vulnerable to the disease.

Seroprotección contra el virus de hepatitis B en pacientes pediátricos con cáncer / Seroprotection against hepatitis B virus in pediatric patients with cancer

Los pacientes con cáncer son población de riesgo para adquirir infección por virus de hepatitis B por estar expuestos a métodos que favorecen la inoculación parenteral del virus. Cuantificar los anticuerpos contra el antígeno de superficie para el virus de hepatitis B en pacientes sin títulos protectores al momento de su ingreso en el servicio de hematooncología pediátrica que recibieron un esquema corto de vacunación (0, 1 y 2 meses). Entre marzo de 2008 y 2009, se recibieron 40 pacientes, excluyéndose 17 posteriormente del estudio, 8 por presentar marcadores positivos de infección para hepatitis B y 9 con títulos mayores de 100UI/L. Dieciséis pacientes sin títulos protectores recibieron vacuna recombinante. Se determinaron serologías para hepatitis B: Antígeno de superficie, Anticuerpo contra el antígeno de superficie y anticore, cada 3 meses, por 1 año, considerándose como títulos protectores anticuerpo contra el antígeno de superficie mayor de 100UI/L De los 16 (100%) pacientes que recibieron vacunación, 15 (94%) alcanzaron títulos protectores, los cuales presentaron descenso del anticuerpo contra el antígeno de superficie durante el tiempo de estudio. Los pacientes vacunados alcanzaron seroprotección con posterior disminución progresiva de sus títulos protectores lo que justifica su revacunación...

Patients with cancer are a population in risk of being infected by Hepatitis B virus as a consequence of being exposed to methods favoring the parenteral inoculation of the virus. Quantifying the antibodies against the surface antigen for Hepatitis B virus in patients without protection titers when admitted to the pediatric hematology-oncology service and who received a short vaccination schedule (0, 1, and 2 months). Between March 2008 and 2009, 40 patients were received, from which later on 17 were excluded from the study since 8 showed infection positive markers for Hepatitis B, and 9 with values higher than 100IU/L. 16 patients without protection titers were recombinant- vaccinated. Serologies for Hepatitis B were determined: Surface Antigen, Antibody against surface antigen, and anticore every 3 months during 1 year, being considered as the antibody protectors against the surface antigen higher than 100IU/L. Out of the 16 patients (100%) who were vaccinated: 15 (94%) reached protection titers, showing antibody decrease against surface antigen in the study term. Vaccinated patients reached seroprotection with later progressive diminishing of protection titers, thus justifying revaccination...

Streptomycin induced protein expression analysis in Mycobacterium tuberculosis by two-dimensional gel electrophoresis & mass spectrometry.

Background & objectives: The resistance of Mycobacterium tuberculosis to streptomycin, a core drug for treatment of category II tuberculosis (TB) has posed a major challenge to the health providers as well as research workers worldwide and has severely compromised the therapeutic options. A significant proportion of streptomycin resistant M. tuberculosis isolates failed to show mutations in conventional targets like rpsL and rrs. Although efflux, permeability, etc. are also known to contribute, yet a substantial proportion of isolates remains resistant suggesting involvement of other unknown mechanism. A resistant isolate may show altered gene as well as protein expression under drug induced conditions and a whole cell proteome analysis under induced conditions might help in further understanding the mechanisms of drug resistance. The present study was therefore designed with the objective to identify proteins related to streptomycin resistance in M. tuberculosis isolate grown in presence and absence of streptomycin (SM). Methods: A clinical isolate of M. tuberculosis from Mycobacterial Repository Centre at the Institute (NJIL & OMD), Agra was grown in Sauton’s medium for 36 h with/without subinhibitory concentration of the drug (2 μg/ml) and the cell lysate of isolates was prepared by sonication and centrifugation. Two-dimensional (2D) gel electrophoresis was employed to study the protein profile. The selected proteins were finally identified by MALDI-TOF mass spectrometry. Results: Our study revealed eight inducible proteins (DnaK, fabG4, DNA-binding, hypothetical, two 14 kDa antigen and two 10 kDa chaperonin) that were upregulated in the presence of drug. Interpretation & conclusion: This preliminary study has thrown light on whether or not and how the resistant isolate responds to streptomycin at its non-toxic but sub-inhibitory concentration. An in-depth study of the upregulated proteins will give an insight into probable sites of drug action other than established primary sites.

Prevalência dos marcadores sorológicos dos vírus das hepatites B e D na área indígena Apyterewa, do grupo Parakanã, Pará, Brasil / Prevalence of hepatitis B and D serological markers in the Parakanã, Apyterewa Indian Reservation, Pará State, Brazil

Com o objetivo de estudar a prevalência dos vírus das hepatites B (HBV) e D (HDV), nas aldeias Apyterewa e Xingu, do grupo Parakanã, e avaliar o impacto da vacinação contra a hepatite B, iniciada nessas aldeias em 1995, foram coletadas, em 2004, 258 amostras de soro para análise dos marcadores sorológicos das hepatites B e D, por técnicas imunoenzimáticas; cujos resultados revelaram padrão de endemicidade moderada com prevalência total de infecção pelo HBV de 55,7 por cento, com 5,4 por cento de portadores do vírus, na aldeia Apyterewa, e de 49,5 por cento, com 1,1 por cento de portadores, na Xingu; 31,4 por cento de anti-HBs+ como marcador isolado nas duas aldeias, e não foi detectada sorologia positiva para o HDV entre portadores do HBV. Caracterizamos, em base laboratorial, a presença de portadores crônicos do HBV, ausência de portadores do HDV e emergência de perfil vacinal entre os susceptíveis, confirmando a efetividade e a necessidade de manter a vacinação, principalmente no primeiro ano de vida, e, ainda, a necessidade de desenvolver vigilância epidemiológica efetiva para detecção precoce da infecção pelo HDV, entre os portadores do HBV.

In order to study the prevalence of hepatitis B (HBV) and D (HDV) viruses in the Parakanã Indians and to evaluate the impact of hepatitis B vaccination beginning there in 1995, 258 serum samples were analyzed in the year 2004 for hepatitis B and D serological markers using immunoenzymatic techniques; the results showed a moderate endemic pattern, with a total prevalence of HBV infection of 55.7 percent and 5.4 percent of virus carriers in the Apyterewa village and 49.5 percent with 1.1 percent of HBV carriers in the Xingu village; 31.4 percent of anti-HBs+ as an isolated marker in both villages and no detection of positive serological tests for HDV among HBV carriers. The laboratory analysis thus showed the presence of chronic HBV carriers, absence of HDV carriers, and an emerging vaccine profile among susceptibles, confirming the effectiveness and need to maintain vaccination, especially in the first year of life, and the need to implement effective epidemiological surveillance for early detection of HDV infection among HBV carriers.

Vacunas del programa nacional PAI 2006: ¿qué hay de nuevo ? / National program vaccines PAI 2006: what's new?

Los progresos en mejorar y desarrollar nuevas estrategias en el Programa Nacional de Inmunizaciones (PAI), han sido muy significativos en los últimos años y aún queda mucho por realizar especialmente en la necesidad de ir incorporando nuevas vacunas, como la anti-hepatitis A o racionalizando el programa pensando en cubrir algunas enfermedades en adolescentes y adultos, o cambiando a vacunas con mayor desarrollo tecnológico como es la anti-pertussis acelular. Se han mejorado coberturas, incorporando nuevas vacunas, como la anti-hepatitis B y se han retirado refuerzos que hoy en día resultan innecesarios, como la BCG en la edad escolar. Se analizan los progresos y el conocimiento actualizado de cada una de las vacunas incorporadas al PAI, Chile 2006.

Prevenção das hepatites virais através de imunização / Viral hepatitis prevention by immunization

OBJETIVO: Apresentar uma revisão atualizada e crítica da prevenção das hepatites virais A e B, através de imunização. FONTE DOS DADOS: Revisão de artigos médicos obtidos através do banco de dados MEDLINE, sendo selecionados os mais atuais e representativos do tema (2000-2006). Foram também pesquisados os sites do Centers for Disease Control and Prevention (CDC) e American Academy of Pediatrics (AAP), da Sociedade Brasileira de Pediatria (SBP) e do Ministério da Saúde do Brasil. SíNTESE DOS DADOS: A prevenção das hepatites virais é um enorme desafio para o sistema de saúde pública dos países e das comunidades médica e científica. Os vírus das hepatites ocasionam importante morbimortalidade no mundo, causando doença hepática aguda e crônica. Vacinas altamente eficazes estão disponíveis no mercado para prevenir novas infecções pelos vírus A e B. Entretanto, as hepatites virais A e B continuam a estar entre as doenças preveníveis por vacinas mais comumente notificadas. Neste artigo, revisamos as vacinas usadas para prevenir essas infecções com o objetivo de expandir o conhecimento e o uso da prevenção dessas doenças infecciosas. CONCLUSÃO: Embora as vacinas contra as hepatites A e B sejam recomendadas para vários grupos de risco, a cobertura vacinal estimada ainda é modesta e existem muitas oportunidades perdidas de vacinação. Para que haja diminuição na incidência das hepatites A e B, duas doenças preveníveis por vacinas, é necessário que os médicos incentivem seus pacientes a receber as vacinas.

Vacunación del niño prematuro: un tema a veces olvidado / Vaccination in premature infants: an issue many times forgotten

Las infecciones bacterianas o virales pueden adquirir mayor gravedad o incluso ser letales en niños prematuros. El retraso de la vacunación en prematuros es frecuente. Esto se debería a falta de claridad sobre la seguridad y respuesta inmune de las vacunas así como a una subestimación de los riesgos de las infecciones en estos niños. No hay evidencia de que la frecuencia de reacciones adversas a vacunas en prematuros sea mayor que en niños de término. Aunque en prematuros extremos la respuesta inmune a vacunas puede ser menor, generalmente es suficiente para una adecuada protección contra infecciones graves. El esquema de inmunización debe ser similar al del niño de término, según edad cronológica. En prematuros debieran considerarse vacunas especiales como anti-neumocócicas conjugadas, anti-influenza. Otras estrategias para proteger a estos niños serían la adherencia rigurosa de los contactos intra domiciliarios al esquema del Programa Ampliado de Inmunizaciones así como el uso de vacunas especiales como la anti-influenza y pertussis acelular en niños mayores y adultos.