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1.
J Leukoc Biol ; 99(3): 505-13, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26394815

RESUMO

The TCR repertoire serves as a reservoir of TCRs for recognizing all potential pathogens. Two major types of T cells, CD4(+) and CD8(+), that use the same genetic elements and process to generate a functional TCR differ in their recognition of peptide bound to MHC class II and I, respectively. However, it is currently unclear to what extent the TCR repertoire of CD4(+) and CD8(+) T cells is different. Here, we report a comparative analysis of the TCRß repertoires of CD4(+) and CD8(+) T cells by use of a 5' rapid amplification of cDNA ends-PCR-sequencing method. We found that TCRß richness of CD4(+) T cells ranges from 1.2 to 9.8 × 10(4) and is approximately 5 times greater, on average, than that of CD8(+) T cells in each study subject. Furthermore, there was little overlap in TCRß sequences between CD4(+) (0.3%) and CD8(+) (1.3%) T cells. Further analysis showed that CD4(+) and CD8(+) T cells exhibited distinct preferences for certain amino acids in the CDR3, and this was confirmed further by a support vector machine classifier, suggesting that there are distinct and discernible differences between TCRß CDR3 in CD4(+) and CD8(+) T cells. Finally, we identified 5-12% of the unique TCRßs that share an identical CDR3 with different variable genes. Together, our findings reveal the distinct features of the TCRß repertoire between CD4(+) and CD8(+) T cells and could potentially be used to evaluate the competency of T cell immunity.


Assuntos
Aminoácidos/análise , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Regiões Determinantes de Complementaridade/análise , Receptores de Antígenos de Linfócitos T alfa-beta/análise , Adulto , Idoso , Genes Codificadores da Cadeia beta de Receptores de Linfócitos T , Humanos , Pessoa de Meia-Idade , Receptores de Antígenos de Linfócitos T alfa-beta/química
2.
Artigo em Inglês | MEDLINE | ID: mdl-23416076

RESUMO

This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.

3.
Int J Cancer ; 109(6): 919-25, 2004 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-15027126

RESUMO

Epstein-Barr virus (EBV) is closely associated with nasopharyngeal carcinoma (NPC), a common cancer in Hong Kong. The EBV-encoded LMP1 protein is believed to play an important role in cell transformation. We have previously identified a prevalent LMP1 variant (2117-LMP1) that is expressed in 86% of primary NPC in Hong Kong. In this study, the biologic phenotypes induced by 2117-LMP1 were compared with those of the prototypic B95.8-LMP1 in an immortalized nasopharyngeal epithelial cell line, NP69. The 2117-LMP1 could induce cell proliferation and resistance to apoptosis induced by growth factor deprivation. Expression of 2117-LMP1 also suppressed expression of p16, p21 and Bax but induced expression of CDK2 and A20. Compared with B95.8-LMP1, 2117-LMP1 could induce a higher migration ability in NP69 cells but was less efficient in inducing morphologic changes, anchorage-independent growth and cell invasion. Relatively weaker ability of 2117-LMP1 than B95.8-LMP1 in upregulation of vimentin, VEGF and MMP9 as well as in downregulation of E-cadherin was observed. 2117-LMP1 could activate higher level of NF-kappaB activity in HEK 293 cells than B95.8-LMP1. The present study supports a role of 2117-LMP1 in NPC development by enhancing cell proliferation, cell death inhibition and migration in premalignant nasopharyngeal epithelial cells. Furthermore, our study reveals significant functional differences between 2117-LMP1 and the prototypic B95.8-LMP1. Our results provide insights into the pathologic significance of this prevalent LMP1 variant, 2117-LMP1, in the development of NPC in the Hong Kong population.


Assuntos
Herpesvirus Humano 4/fisiologia , Neoplasias Nasofaríngeas/virologia , Proteínas Proto-Oncogênicas c-bcl-2 , Proteínas da Matriz Viral/fisiologia , Quinases relacionadas a CDC2 e CDC28/metabolismo , Caderinas/metabolismo , Divisão Celular , Movimento Celular , Sobrevivência Celular , Quinase 2 Dependente de Ciclina , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Inibidor de Quinase Dependente de Ciclina p21 , Ciclinas/metabolismo , Proteínas de Ligação a DNA , Hong Kong , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Metaloproteinase 9 da Matriz/metabolismo , NF-kappa B/metabolismo , Neoplasias Nasofaríngeas/metabolismo , Neoplasias Nasofaríngeas/patologia , Proteínas Nucleares , Fenótipo , Proteínas/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Células Tumorais Cultivadas , Proteína 3 Induzida por Fator de Necrose Tumoral alfa , Regulação para Cima , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proteína X Associada a bcl-2
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