Chlamydia trachomatis-infected macrophages induce apoptosis of activated T cells by secretion of tumor necrosis factor-α in vitro

• Published in: Medical microbiology and immunology 2004-02, Vol.193 (1), p.45-52
• Main Authors: JENDRO, Michael C, FINGERLE, Frederik, DEUTSCH, Tobias, LIESE, Andrea, KÖHLER, Lars, KUIPERS, Jens G, RAUM, Elke, MARTIN, Michael, ZEIDLER, Henning
• Format: Article
• Language: English
• Subjects: Adalimumab; Antibodies; Antibodies, Monoclonal - immunology; Antibodies, Monoclonal, Humanized; Apoptosis; Apoptosis Regulatory Proteins; Bacteriology; Biological and medical sciences; Catalase - metabolism; Cell Communication; Cell Culture Techniques; Chlamydia trachomatis; Chlamydia trachomatis - pathogenicity; Coculture Techniques; fas Receptor - pharmacology; Flow Cytometry; Fundamental and applied biological sciences. Psychology; Humans; Lymphocyte Activation; Macrophages - immunology; Macrophages - microbiology; Medical sciences; Membrane Glycoproteins - immunology; Microbiology; Miscellaneous; Phytohemagglutinins - metabolism; Propidium; T-Lymphocytes - immunology; T-Lymphocytes - physiology; TNF-Related Apoptosis-Inducing Ligand; Tumor Necrosis Factor-alpha - antagonists & inhibitors; Tumor Necrosis Factor-alpha - immunology; Tumor Necrosis Factor-alpha - secretion; Tumors
• ISSN: 0300-8584; 1432-1831
• DOI: 10.1007/s00430-003-0182-1

Chlamydia trachomatis-infected macrophages induce T cell apoptosis. This ability might promote intracellular survival of Chlamydia and perpetuate chronic chlamydial infection. The purpose of this study was to examine the molecular mechanisms by which C. trachomatis-infected macrophages induce T cell apoptosis. Monocytes and T cells were isolated from the peripheral blood of healthy donors. Macrophages were infected with C. trachomatis, and autologous T cells were stimulated by mitogen. After 6 days, both populations were cultured together using a two-chamber transwell membrane system to differentiate between mechanisms involving either cell-to-cell contact or secretion of apoptotic factors. Apoptotic T cells were identified by propidium iodide through-flow cytometry, and tumor necrosis factor-alpha (TNF-alpha) concentrations were measured by enzyme-linked immunosorbent assay. Antagonists of TNF-alpha, the Fas (CD95) molecule, TNF-related apoptosis-inducing ligand (TRAIL), and catalase were added to differentiate between the pathways of apoptosis. C. trachomatis-infected macrophages significantly induced T cell apoptosis by cell-to-cell contact (mean +/- standard deviation, 30+/-4%; P