Updates on current advances in gene therapy / Actualizaciones acerca de los adelantos presentes en terapia genética

Gene therapy is the attempt to treat diseases by means of genetic manipulation. Numerous challenges remain to be overcome before it becomes available as a safe and effective treatment option. Retroviruses and adenoviruses are among the most commonly used viral vectors in trials. The retrovirus introduces the gene it carries into the target cell genome while the adenovirus introduces the gene into the target cell nucleus without incorporating it into the target cell genome. Other viral vectors such as adenoassociated viruses, pseudotyped viruses and herpes simplex viruses, are also gaining popularity. Proposed nonviral methods for gene transfer include physical methods and the employment of chemical vectors (lipoplexes, polyplexes and inorganic nanoparticles). Recent studies have investigated potential applications of gene therapy in correcting genetic diseases, treating malignant disorders and for treatment of other diseases. Trials on gene therapy for SCID and Leber's congenital amaurosis have achieved considerable success, but the widely publicized adverse reaction in Xlinked SCID patient receiving gene therapy raised concerns for safety profile of gene therapy. For that, several methods of improving safety and efficacy of gene therapy have been proposed. At present, the three main gene therapy strategies for treatment of cancer are application to oncolytic viruses, suicidegene therapy and genebased immunotherapy. Gendicine, the first approved anticancer drugs based on the use of gene therapy principle, is based on the use of oncolytic viruses. More evidence for wider clinical applications of gene therapy are expected as more gene therapy studies progress from the preclinical phase to clinical trial.

La terapia genética es el intento de tratar enfermedades por medio de la manipulación genética. Quedan aún numerosos retos que superar antes de que esté tipo de tratamiento se encuentre disponible como una opción segura y eficaz. Los retrovirus y los adenovirus se hallan entre los vectores virales más comúnmente utilizados en ensayos: el retrovirus introduce el gen - del cual es portador - en el genoma de la célula de destino, mientras el adenovirus introduce el gen en el núcleo de la célula de destino sin incorporarlo al genoma de la célula de destino. Otros vectores virales tales como los virus adenoasociados, los virus pseudotipados, y los virus del herpe simple, también están ganando popularidad. Los métodos no virales propuestos para la transferencia de genes incluyen tanto métodos físicos como el empleo de vectores químicos (lipoplexes, polisomas y nanopartículas inorgánicas). Estudios recientes han investigado las aplicaciones potenciales de la terapia genética en la corrección de las enfermedades genéticas, el tratamiento de los trastornos malignos y para el tratamiento de otras enfermedades. Los ensayos de terapia genética para SCID y la amaurosis congénita de Leber han logrado un éxito considerable, pero la reacción adversa ampliamente divulgada en el caso de los pacientes con SCID ligada al cromosoma, que recibían terapia génica, causó preocupación en cuanto al perfil de seguridad de la terapia génica. Por esa razón, se han propuesto varios métodos para mejorar la seguridad y la eficacia de la terapia génica. En la actualidad, las tres estrategias principales de terapia de genes para el tratamiento del cáncer son la aplicación de virus oncolíticos, la terapia con gen suicida, y la inmunoterapia genética. La gendicina, el primer medicamento anticancerígeno aprobado, basado en el uso del principio de la terapia génica, se basa en el uso de virus oncolíticos. Se esperan más evidencias a favor de aplicaciones clínicas más amplias de la terapia génica, a medida que más estudios de terapia génica progresan de la fase preclínica a la fase de ensayo clínico.

Diagnóstico microbiológico de las infecciones de transmisión sexual (ITS): Parte 1. ITS no virales / Microbiological diagnosis of sexually transmitted infections (STI): Part 1. Non-viral STI

Non-viral sexually transmitted infections (STI) are an important cause of physical, psychological and social distress, have severe consequences for women's reproductive health and may be transmitted to the newborn child. These infections are also risk factors for the acquisition and transmission of HIV and other STI, and for premature labor. In the last years we have observed a gradual decrease in the national incidence of gonorrhea. The implementation of a screening program in our country for Chlomydia trachomatis is necessary, since up to 80 percent of infections in women are asymptomatic. Due to medical, psychosocial and legal reasons, laboratory diagnosis of STI has to be certain. This offers a great challenge to laboratories. Since etiological agents are susceptible to environmental conditions, present a high adaptation to their human host and have particular physiological characteristics, their laboratory diagnosis is more difficult than diagnosis of conventional microorganisms. Otherwise, the diagnostic techniques currently available for non-viral STI are characterized by their excellent sensitivity and specificity, which result of great interest given the curable nature of these infections. Clinical specimens obtained for diagnosis of STI and other genital infections, such as bacterial vaginosis or Candidiasis represent a large proportion of specimens processed by clinical laboratories. Thus, the creation of norms and quality control guidelines for laboratories which diagnose these infections, and also the epidemiologic and genetic surveillance of circulating sex transmitted microorganisms should be considered a priority in our country. The objective of this study is to review current literature on accurate diagnostic procedures especially for three non-viral STI agents: C. trachomatis, N. gonorrhoeae, and Trichomonas vaginalis.