Conformational and biochemical differences in the TCR/CD3 complex of CD8+ vs CD4+ mature lymphocytes revealed in the absence of CD3γ

Mature CD4(+) and CD8(+) T lymphocytes are believed to build and express essentially identical surface alphabeta T-cell receptor-CD3 (TCR.CD3) complexes. However, TCR.CD3 expression has been shown to be more impaired in CD8(+) cells than in CD4(+) cells when CD3gamma is absent in humans or mice. We...

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Detalles Bibliográficos
Autores: Zapata, David A., Pacheco Castro, Alberto, Torres, Pilar S., Ramiro, Almudena R., San José, Ester, Alarcón, Balbino, Alibaud, Laeticia, Rubin, Bent, Toribio, María L., Regueiro González-Barros, José Ramón
Tipo de recurso: artículo
Fecha de publicación:1999
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/107334
Acceso en línea:https://hdl.handle.net/20.500.14352/107334
Access Level:acceso abierto
Palabra clave:612.017
Inmunología
2412 Inmunología
Descripción
Sumario:Mature CD4(+) and CD8(+) T lymphocytes are believed to build and express essentially identical surface alphabeta T-cell receptor-CD3 (TCR.CD3) complexes. However, TCR.CD3 expression has been shown to be more impaired in CD8(+) cells than in CD4(+) cells when CD3gamma is absent in humans or mice. We have addressed this paradox by performing a detailed phenotypical and biochemical analysis of the TCR.CD3 complex in human CD3gamma-deficient CD8(+) and CD4(+) T cells. The results indicated that the membrane TCR.CD3 complex of CD8(+) T lymphocytes was conformationally different from that of CD4(+) lymphocytes in the absence of CD3gamma. In addition, CD8(+), but not CD4(+), CD3gamma-deficient T lymphocytes were shown to contain abnormally glycosylated TCRbeta proteins, together with a smaller, abnormal TCR chain (probably incompletely processed TCRalpha). These results suggest the existence of hitherto unrecognized biochemical differences between mature CD4(+) and CD8(+) T lymphocytes in the intracellular control of alphabetaTCR. CD3 assembly, maturation, or transport that are revealed when CD3gamma is absent. Such lineage-specific differences may be important in receptor-coreceptor interactions during antigen recognition.