1. CD4 T cells producing IFN-γ in the lungs of mice challenged with mycobacteria express a CD27-negative phenotype.
- Author
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Lyadova, I. V., Oberdorf, S., Kapina, M. A., Apt, A. S., Swain, S. L., and Sayles, P. C.
- Subjects
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LYMPHOCYTES , *CARDIOPULMONARY system , *LUNG diseases , *MYCOBACTERIAL diseases , *GENOTYPE-environment interaction , *T cells - Abstract
Protection against tuberculosis depends upon the generation of CD4+ T cell effectors capable of producing IFN-γ and stimulating macrophage antimycobacterial function. Effector CD4+ T cells are known to express CD44hiCD62Llo surface phenotype. In this paper we demonstrate that a population of CD44hiCD62Llo CD4+ effectors generated in response toMycobacterium bovisBCG orM. tuberculosisinfection in C57BL/6 mice is heterogeneous and consists of CD27hi and CD27lo T cell subsets. These subsets exhibit a similar degree ofin vivoproliferation, but differ by the capacity for IFN-γ production.Ex vivoisolated CD27lo T cells express higher amounts of IFN-γ RNA and contain higher frequencies of IFN-γ producers compared to CD27hi subset, as shown by real-time PCR, intracellular staining for IFN-γ and ELISPOT assays. In addition, CD27lo CD4+ T cells uniformly express CD44hiCD62Llo phenotype. We propose that CD27lo CD44hiCD62Llo CD4+ T cells represent highly differentiated effector cells with a high capacity for IFN-γ secretion and antimycobacterial protection at the site of infection. [ABSTRACT FROM AUTHOR]
- Published
- 2004
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