ABSTRACT
En los ó;ºltimos aó;±os la terapia gó;©nica se ha posicionado como una opció;n real y segura en el desarrollo de alternativas terapó;©uticas para la cura y la prevenció;n de diferentes enfermedades. Consiste en la inserció;n de material genó;©tico en un tejido o có;©lula defectuosa, mediante el uso de un vector. Existen varias consideraciones para seleccionar el vector más apropiado, incluyendo el potencial de unió;n y entrada a la có;©lula diana, la capacidad de transferencia del material genó;©tico al nó;ºcleo, la habilidad de expresió;n del inserto y la ausencia de toxicidad. En el panorama actual, los vectores virales más utilizados son los derivados de los virus adenoasociados (AAV). Características como su bioseguridad, baja toxicidad y tropismo selectivo, han posibilitado su evaluació;n como opció;n terapó;©utica en un amplio nó;ºmero de enfermedades monogó;©nicas o complejas. A pesar de sus ventajas, los vectores AAV presentan inconvenientes, siendo el más importante la respuesta inmune del paciente al vector, especialmente la respuesta mediada por anticuerpos neutralizantes (NAb). Los NAb disminuyen la transducció;n del vector e impiden la expresió;n del gen que transporta, limitando su aplicació;n clínica. Por lo tanto, identificar y cuantificar la presencia y actividad de los NAbs, es el primer paso en cualquier protocolo de terapia gó;©nica con vectores AAV. La presencia de NAb depende principalmente de la exposició;n al virus en la naturaleza y varía drásticamente segó;ºn edad, localizació;n geográfica y estado de salud de la persona evaluada.
In recent years, gene therapy has been positioned as a real and safe option in the development of therapeutic alternatives for the cure and prevention of different diseases. It consists in the insertion of genetic material in a defective tissue or cell, through the use of a vector. There are several considerations for selecting the most appropriate vector, including the potential for binding and entry to the target cell, the ability of the genetic material to transfer to the nucleus, the ability to express the insert, and the absence of toxicity. In the current scenario, the most commonly used viral vectors are those derived from adeno-associated viruses (AAV). Characteristics such as biosafety, low toxicity and selective tropism have enabled its evaluation as a therapeutic option in many monogenic or complex diseases. Despite their advantages, AAV vectors have drawbacks, the most important being the patientâs immune response to the vector, especially the response mediated by neutralizing antibodies (NAb). NAbs decrease the transduction of the vector and prevent the expression of the gene it transports, limiting its clinical application. Therefore, identifying and quantifying the presence and activity of NAbs is the first step in any gene therapy protocol with AAV vectors. The presence of NAbs depends mainly on exposure to the virus in nature and varies drastically according to age, geographic location and health status of the person evaluated.
Subject(s)
Humans , Male , Female , Genetic Therapy/methods , Dependovirus/genetics , Dependovirus/immunology , Parvoviridae Infections/genetics , Parvoviridae Infections/immunology , Parvoviridae Infections/virology , Antibodies, Neutralizing/analysis , Serogroup , Genetic Vectors , Antibodies, Viral/analysisABSTRACT
Red Baby Syndrome is a new disease seen in infants and young children. Dramatic onset of clinical symptoms with high intensity, short duration and lack of similarity with other cutaneous lesions makes it distinct. Of 50 such patients studied over a period of 5 years, half were below one year of age. Abrupt onset of high fever and generalized erythema involving the entire skin, which is swollen and tender is characteristic. These children were highly irritable and had paradoxical cry when cuddled. Rapid resolution of symptoms occurred in 7-10 days with extensive desquamation. Routine investigations were normal, C-reactive protein was raised only in 10 patients. Human Parvo virus B-19 IgM antibodies were positive in 15 out of 24 patients. Real time polymerase chain reaction was positive for human parvovirus B 19 DNA in one. Histopathological changes in the skin biopsy showed post infectious vascular injury pattern.