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El origen del VIH-1 en el chimpancé Pan troglodytes troglodytes
F Gao1, E Bailes, D L Robertson
1Department of Medicine, University of Alabama at Birmingham, 35294, USA.
Nature
|February 16, 1999
Resumen
La subespecie del chimpancé central (Pan troglodytes troglodytes) es el reservorio principal para el virus de la inmunodeficiencia humana tipo 1 (VIH-1). Esta subespecie ha sido la fuente de al menos tres transmisiones zoonóticas independientes del virus de la inmunodeficiencia simiana (SIVcpz) a los humanos.
Área de la Ciencia:
- Virología Virología.
- La primatología es la primatología.
- Biología evolutiva Biología evolutiva.
- Enfermedades zoonóticas Las enfermedades zoonóticas son enfermedades zoonóticas.
Sus antecedentes:
- Los virus de la inmunodeficiencia humana (VIH-1 y VIH-2) son infecciones zoonóticas originadas en primates no humanos.
- Si bien el reservorio del virus de inmunodeficiencia simio (SIV) para el VIH-2 se identifica como el mangabey de hollín, el origen del VIH-1 sigue sin estar claro.
- Estudios anteriores identificaron el virus de inmunodeficiencia simio en chimpancés (SIVcpz) relacionado con el VIH-1, pero las infecciones documentadas fueron raras y divergentes.
Objetivo del estudio:
- Para identificar el reservorio natural del VIH-1.
- Investigar los orígenes evolutivos y la dinámica de transmisión de las cepas SIVcpz.
- Determinar las subespecies de chimpancés infectados por SIVcpz y su relación filogenética con el VIH-1.
Principales métodos:
- Secuenciación del genoma de una nueva cepa SIVcpz (SIVcpzUS).
- Análisis de ADN mitocondrial para determinar las subespecies de chimpancés infectados con SIVcpz.
- Análisis filogenético de cepas SIVcpz y VIH-1.
Principales resultados:
- Dos subespecies de chimpancés, el central (P. t. troglodytes) y el oriental (P. t. schweinfurthii), albergan linajes SIVcpz distintos.
- Todas las cepas humanas conocidas del VIH-1 (grupos M, N, O) están estrechamente relacionadas con el linaje SIVcpz encontrado en P. t. troglodytes.
- El grupo N del VIH-1 exhibe secuencias de mosaico, lo que indica la recombinación en un huésped chimpancé, y su área de distribución natural se solapa con las áreas endémicas del VIH-1.
Conclusiones:
- La subespecie del chimpancé central (Pan troglodytes troglodytes) es el reservorio principal para el VIH-1.
- Se han producido al menos tres transmisiones zoonóticas independientes de SIVcpz de P. t. troglodytes a humanos.
- Comprender el reservorio de SIVcpz en los chimpancés es crucial para prevenir futuras transmisiones zoonóticas del VIH-1.
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