The major CD8 T cell effector memory subset in the normal and Chlamydia trachomatis-infected human endocervix is low in perforin
Autor: | Alison J. Quayle, Maria E. Lewis, Joyce S. A. Ibana, Constance Porretta, David H. Martin, Leann Myers, Stephanie N. Taylor |
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Rok vydání: | 2012 |
Předmět: |
lcsh:Immunologic diseases. Allergy
Adult CD4-Positive T-Lymphocytes Male Adolescent T cell Immunology Chlamydia trachomatis Cervix Uteri CD8-Positive T-Lymphocytes medicine.disease_cause Granzymes Interferon-gamma Young Adult 03 medical and health sciences Interleukin 21 0302 clinical medicine T-Lymphocyte Subsets medicine Humans Cytotoxic T cell 030304 developmental biology Cytolytic granule 0303 health sciences biology Perforin Effector Epithelial Cells Chlamydia Infections Flow Cytometry Immunohistochemistry Killer Cells Natural medicine.anatomical_structure Cellular Microenvironment biology.protein Female lcsh:RC581-607 Immunologic Memory Endocervix Research Article HeLa Cells 030215 immunology |
Zdroj: | BMC Immunology BMC Immunology, Vol 13, Iss 1, p 66 (2012) |
ISSN: | 1471-2172 |
DOI: | 10.1186/1471-2172-13-66 |
Popis: | Background The local tissue microenvironment plays an important role in the induction, homing, maintenance and development of effector functions of T cells. Thus, site-specific differences in phenotypes of mucosal and systemic T cell populations have been observed. Chlamydia trachomatis most commonly infects the endocervix in women, yet little is known about Chlamydia-specific effector T cell immunity at this unique mucosal site. Our previous flow-cytometry-based study of cervical-cytobrush retrieved cells indicated that CD8 T cells are significantly increased in the C. trachomatis-infected human endocervix. The cytolytic function of CD8 T cells is important in the protective immunity against many intracellular pathogens, and requires the cytolytic granule perforin to facilitate the entry of other molecules that mediate the lysis of target cells. Determination of perforin expression of the CD8 T cell population in the endocervix would therefore provide insights on the granule-mediated cytolytic potential of these cells at this site. Results Our histological data revealed that C. trachomatis-infected tissues have significantly higher numbers of CD3 and CD8 T cells compared to non-infected tissues (p+ cells do not express perforin in situ. A subsequent flow cytometric analysis of paired blood and endocervix-derived cells (n=16) revealed that while all the CD8 T cell subsets: naïve, effector memory (TEM), central memory (TCM) and terminally differentiated effector memory (TEMRA) can be found in the blood, the endocervix is populated mainly by the TEM CD8 T cell subset. Our data also showed that perforin expression in the TEM population is significantly lower in the endocervix than in the blood of C. trachomatis positive women (n=15; pC. trachomatis-negative individuals (n=6; pin vitro co-culture study suggests that the exposure of HeLa 229 cervical epithelial cells to IFN gamma could potentially induce a decrease in perforin content in CD8 TEM cells in the same microenvironment. Conclusions The low perforin content of CD8 TEM cells in the endocervix, the local site of C. trachomatis infection in women, may reflect the unique immunological environment that balances immune protection against sexually transmitted infections and immune- tolerance to support conception. |
Databáze: | OpenAIRE |
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