Impaired expression of perforin and granulysin in CD8+ T cells at the site of infection in human chronic pulmonary tuberculosis

Infect Immun. 2007 Nov;75(11):5210-22. doi: 10.1128/IAI.00624-07. Epub 2007 Jul 30.

Abstract

Protective immunity in tuberculosis is dependent on the coordinated release of cytolytic effector molecules from effector T cells and the subsequent granule-associated killing of infected target cells. In this study, we investigated the expression of cytolytic (perforin and granzyme A) and antimicrobial (granulysin) molecules at the single-cell level in cryopreserved lung tissue from patients with chronic, progressive tuberculosis disease. Quantification of protein-expressing cells was performed by in situ imaging, while mRNA levels in the infected tissue were analyzed by real-time PCR. Persistent inflammation, including excessive expression of inducible nitric oxide synthase in CD68+ macrophages and significant infiltration of CD3+, CD8+ and CD4+ T cells, was evident in tuberculosis lesions in all patients. However, despite the accumulation of CD3+ T cells, perforin- and granulysin-expressing CD3+ T cells were detected at two- to threefold-lower ratios in the tuberculosis lesions than in distal lung parenchyma and uninfected control lungs, respectively. This was evident at both the protein and mRNA levels. Moreover, perforin- and granulysin-expressing CD8+ T cells were scarce in individual granulomas within the tuberculosis lesions. In contrast, significant up-regulation of granzyme A-expressing CD3+ T cells was evident in the lesions from all patients. Confocal microscopy revealed coexpression of perforin and granulysin, primarily in CD8+ T cells; however, this expression was lower in the tuberculosis lesions. These findings suggest that symptomatic, chronic tuberculosis disease is associated with insufficient up-regulation of perforin and granulysin coexpression in CD8+ T cells at the local site of infection.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Antigens, CD / analysis
  • Antigens, Differentiation, Myelomonocytic / analysis
  • Antigens, Differentiation, T-Lymphocyte / biosynthesis*
  • CD3 Complex / analysis
  • CD4-Positive T-Lymphocytes / immunology
  • CD8-Positive T-Lymphocytes / immunology*
  • Female
  • Gene Expression
  • Granzymes / biosynthesis
  • Humans
  • Immunohistochemistry
  • Lung / chemistry
  • Lung / immunology*
  • Macrophages / immunology
  • Male
  • Microscopy, Confocal
  • Middle Aged
  • Perforin / biosynthesis*
  • RNA, Messenger / analysis
  • Reverse Transcriptase Polymerase Chain Reaction
  • T-Lymphocyte Subsets / immunology
  • Tuberculosis, Pulmonary / immunology*

Substances

  • Antigens, CD
  • Antigens, Differentiation, Myelomonocytic
  • Antigens, Differentiation, T-Lymphocyte
  • CD3 Complex
  • CD68 antigen, human
  • GNLY protein, human
  • RNA, Messenger
  • Perforin
  • Granzymes