International Immunology Advance Access published online on November 13, 2007
International Immunology, doi:10.1093/intimm/dxm122
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Priming of CD4+ T cells with porin of Shigella dysenteriae activates the cells toward type 1 polarization
Division of Immunology, National Institute of Cholera and Enteric Diseases, P-33, CIT Road, Scheme XM, Kolkata 700 010, West Bengal, India
Correspondence to: Correspondence to: T. Biswas; E-mail: shigellaporin{at}yahoo.com
Macrophages treated with porin of Shigella dysenteriae were potent stimulators of naive Th cells since the porin-pulsed macrophages strongly proliferated the T cells and up-regulated the activation molecules CD69 and CD25 on CD4+ T cells in allogeneic mixed leukocyte reaction. Immunization of C57BL/6 mice with porin selectively induced the intracellular expression and release of IFN-
and had no effect on IL-4 expression. In parallel to the predominant release of the Th1 cytokine IFN-
, up-regulation of CCR5 on the immune CD4+ T cells and messenger ribonucleic acid (mRNA) expression of the T cell chemokines macrophage inflammatory protein-1
and regulated on activation normal T cell expressed and secreted showed Th1 bias. The porin-primed CD4+ T cells expressed the mRNA for T-box expressed in T cells, a Th1-specific transcription factor confirming the adjuvant-induced transition of T cells to polarized effector Th1 cells. The immune CD4+ T cells proliferated and released IL-2 and IFN-
profoundly in response to re-challenge with porin-pulsed macrophages but not to BSA-pulsed macrophages in vitro, which demonstrated the presence of porin-specific CD4+ T cells of Th1 phenotype. The study highlights that porin has the capacity of an adjuvant to unfold and maintain the T cell function and thereby to activate adaptive immunity.
Keywords: chemokines, IFN-
, porin, Th cells, type 1 polarization
Transmitting editor: A. Falus
Received 8 August 2007, accepted 17 October 2007.