|
|
||||||||

* Department of Veterinary Molecular Biology, Montana State University, Bozeman, MT 59717; and
Trudeau Institute, Saranac Lake, NY 12983
Pneumocystis, a fungal, extracellular pathogen causes a life-threatening pneumonia in patients with severe immunodeficiencies. In the absence of CD4 T cells, Pneumocystis infection results in vigorous CD8 T cell influx into the alveolar and interstitial spaces of the lung. This response results in lung damage characterized by low pO2 and albumin leakage into the bronchoalveolar lavage fluid similar to other CD8 T cell-mediated interstitial lung diseases. How this extracellular pathogen elicits a CD8 T cell response is not clear, and it was the aim of our study to determine the Ag specificity of the recruited CD8 T cells and to determine whether MHC class I (MHC I) expression was necessary to initiate lung damage. Using an adoptive T cell-transfer model with either polyclonal wild-type CD8 T cells or transgenic influenza virus-specific CD8 T cells we found that CD8 T cell recruitment is Ag-specific and requires the continuous presence of the Pneumocystis pathogen. Bone marrow chimera experiments using Rag-1 and
2-microglobulin-deficient mice as hosts demonstrated a requirement for MHC I expression on nonbone marrow-derived cells of the lung. This suggests either direct processing of Pneumocystis Ags by nonbone marrow-derived cells of the lung or the induction of lung damage triggered by a lung-specific autoantigen. Using perforin-, Fas-, and IFN-
-deficient animals, we showed that these molecules are not directly involved in the CD8-mediated lung damage. However, CD8 T cell-mediated lung damage is Ag-specific is induced by a MHC I-expressing nonbone marrow-derived cell in the lung and is dependent on the continued presence of live Pneumocystis.
This article has been cited by other articles:
![]() |
S. P. Bhagwat, T. W. Wright, and F. Gigliotti Anti-CD3 Antibody Decreases Inflammation and Improves Outcome in a Murine Model of Pneumocystis Pneumonia J. Immunol., January 1, 2010; 184(1): 497 - 502. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. S. Pryhuber, H. L. Huyck, S. Bhagwat, M. A. O'Reilly, J. N. Finkelstein, F. Gigliotti, and T. W. Wright Parenchymal Cell TNF Receptors Contribute to Inflammatory Cell Recruitment and Respiratory Failure in Pneumocystis carinii-Induced Pneumonia J. Immunol., July 15, 2008; 181(2): 1409 - 1419. [Abstract] [Full Text] [PDF] |
||||
![]() |
I Petrache, K Diab, K S Knox, H L Twigg III, R S Stephens, S Flores, and R M Tuder HIV associated pulmonary emphysema: a review of the literature and inquiry into its mechanism Thorax, May 1, 2008; 63(5): 463 - 469. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. Meissner, M. Rutkowski, A. L. Harmsen, S. Han, and A. G. Harmsen Type I Interferon Signaling and B Cells Maintain Hemopoiesis during Pneumocystis Infection of the Lung J. Immunol., May 15, 2007; 178(10): 6604 - 6615. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. R. Rapaka, E. S. Goetzman, M. Zheng, J. Vockley, L. McKinley, J. K. Kolls, and C. Steele Enhanced Defense against Pneumocystis carinii Mediated by a Novel Dectin-1 Receptor Fc Fusion Protein J. Immunol., March 15, 2007; 178(6): 3702 - 3712. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |