• JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
 
  Bookmark and Share
 
 
Doctoral Thesis
DOI
10.11606/T.42.2008.tde-03062008-172716
Document
Author
Full name
Claudia Augusta Zago
Institute/School/College
Knowledge Area
Date of Defense
Published
São Paulo, 2008
Supervisor
Committee
Lima, Maria Regina D'Imperio (President)
Câmara, Niels Olsen Saraiva
Kallas, Esper Georges
Russo, Momtchilo
Viola, João Paulo de Biaso
Title in Portuguese
O papel das células Treg e da IL-2 na resposta policlonal de células CD4+ durante a infecção pelo Plasmodium chabaudi.
Keywords in Portuguese
Plasmodium chabaudi
Células T reguladoras
IL-2
Linfócitos
Malária
Resposta imune
Abstract in Portuguese
Durante a ativação policlonal induzida pelo P. chabaudi a maior fonte de IL-2 são as células CD4+ ativadas, além disso, acorre a expansão de células Treg. No dia 7 após a infecção, a ausência de células Treg leva a uma exacerbação da ativação de células CD4+, além de altos níveis de anticorpos anti-P.chabaudi e auto-anticorpos. A neutralização da IL-2, com Mab anti-IL-2 JES6-1, na fase aguda da infecção leva a uma redução no número de células Treg. No dia 20 de infecção, a freqüência de células CD4+ ativadas esteve elevada e as células Treg voltaram aos níveis basais. Experimentos in vitro mostraram que a neutralização da IL-2 não altera a proliferação antígeno-específica de células CD4+ da fase aguda da infecção, porém, em tempos tardios da infecção houve um drástico aumento na freqüência de células CD4+ que proliferam em resposta a eritrócitos parasitados. Podemos concluir que a IL-2 e as células Treg são capazes de limitar a ativação policlonal induzida pelo P. chabaudi ainda que com cinéticas distintas.
Title in English
The role of Treg cells and IL-2 in polyclonal CD4+ T cells response during Plasmodium chabaudi infection.
Keywords in English
Plasmodium chabaudi
IL-2
Immune response
Lymphocytes
Malaria
Regulatory T cells
Abstract in English
Polyclonal activation during P. chabaudi infection results on a huge IL-2 production by activated CD4+ T cells, besides a considerable expansion of Treg cells. At day 7 after infection in the absence of Treg cells there is an enhanced response of activated CD4+ T cells, an increase of Abs anti-P.chabaudi and autoantibody production. Neutralization of IL-2 with Mab anti-IL2 JES6-1 during acute infection reveals a markedly reduction in Treg-cells number. At day 20 of infection we can observe an increase on activated CD4+ T cells frequency. Moreover, Treg cells return to values similar to controls. IL-2 in vitro assays during acute infection results on Ag-specific CD4+ T cells proliferation, on the other hand, at the late infection, we observed a huge increase of CD4+ T cells frequency that strongly response to PRBC. Our findings suggest that IL-2 and Treg cells are capable of restricting PLA during P.chabaudi infection, although with different kinetics.
 
WARNING - Viewing this document is conditioned on your acceptance of the following terms of use:
This document is only for private use for research and teaching activities. Reproduction for commercial use is forbidden. This rights cover the whole data about this document as well as its contents. Any uses or copies of this document in whole or in part must include the author's name.
Publishing Date
2008-06-11
 
WARNING: Learn what derived works are clicking here.
All rights of the thesis/dissertation are from the authors
Centro de Informática de São Carlos
Digital Library of Theses and Dissertations of USP. Copyright © 2001-2020. All rights reserved.