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Updated: Jun 16, 2026
09:49
Induction and Assessment of Class Switch Recombination in Purified Murine B Cells
Published on: August 14, 2010
El cambio de isotipo de un transgen de cadena pesada de inmunoglobulina ocurre por recombinación de ADN entre
R M Gerstein1, W N Frankel, C L Hsieh
1Department of Pathology, Tufts University School of Medicine, Boston, Massachusetts 02111.
Cell
|November 2, 1990
Resumen
Los ratones transgénicos muestran que la conmutación de genes de anticuerpos puede ocurrir entre cromosomas, no solo dentro de uno. Esta recombinación intercromosómica utiliza los mismos mecanismos que la conmutación normal y puede causar translocaciones en tumores de células B.
Área de la Ciencia:
- Inmunología Inmunología.
- Genética La genética.
- Biología Molecular Biología Molecular
Sus antecedentes:
- Los ratones transgénicos con inmunoglobulina mu transgenes de cadena pesada se someten a la conmutación de isotipos.
- El mecanismo de esta conmutación transgénica no se había caracterizado previamente.
Objetivo del estudio:
- Caracterizar el mecanismo de la conmutación de isotipos transgénicos de la cadena pesada de inmunoglobulina.
- Para determinar si la conmutación de isotipos puede ocurrir entre diferentes cromosomas.
Principales métodos:
- Localización del sitio de inserción de transgenes utilizando retrovirus endógenos polimórficos como marcadores genéticos en ratones de cruce trasero.
- Análisis de la recombinación del ADN durante el cambio de isotipo.
Principales resultados:
- El sitio de inserción del transgen mu fue mapeado en el cromosoma 5.
- El locus de la cadena pesada de la inmunoglobulina endógena se encuentra en el cromosoma 12.
- Se demostró que la conmutación de isotipos transgénicos implica la recombinación del ADN intercromosómico.
- Los mismos mecanismos enzimáticos parecen mediar tanto la conmutación normal como la intercromosómica.
Conclusiones:
- La conmutación de isotipos de genes de anticuerpos puede ocurrir entre cromosomas.
- El mecanismo de conmutación de isotipos puede inducir translocaciones cromosómicas, similares a las observadas en los tumores de células B que involucran el gen c-myc.
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