Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2007-9-5
pubmed:abstractText
CD8+ T cells are important for immunity to the intracellular bacterial pathogen Chlamydia pneumoniae (Cpn). Recently, we reported that type 1 CD8+ (Tc1) from Cpn-infected B6 mice recognize peptides from multiple Cpn Ags in a classical MHC class Ia-restricted fashion. In this study, we show that Cpn infection also induces nonclassical MHC class Ib-(H2-M3)-restricted CD8+ T cell responses. H2-M3-binding peptides representing the N-terminal formylated sequences from five Cpn Ags sensitized target cells for lysis by cytolytic effectors from the spleens of infected B6 mice. Of these, only peptides fMFFAPL (P1) and fMLYWFL (P4) stimulated IFN-gamma production by infection-primed splenic and pulmonary CD8+ T cells. Studies with Cpn-infected Kb-/-/Db-/- mice confirmed the Tc1 cytokine profile of P1- and P4-specific CD8+ T cells and revealed the capacity of these effectors to exert in vitro H2-M3-restricted lysis of Cpn-infected macrophages and in vivo pulmonary killing of P1- and P4-coated splenocytes. Furthermore, adoptive transfer of P1- and P4-specific CD8+ T cells into naive Kb-/-/Db-/- mice reduced lung Cpn loads following challenge. Finally, we show that in the absence of MHC class Ia-restricted CD8+ T cell responses, CD4+ T cells are largely expendable for the control of Cpn growth, and for the generation, memory maintenance, and secondary expansion of P1- and P4-specific CD8+ T cells. These results suggest that H2-M3-restricted CD8+ T cells contribute to protective immunity against Cpn, and that chlamydial Ags presented by MHC class Ib molecules may represent novel targets for inclusion in anti-Cpn vaccines.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0022-1767
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
179
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3947-57
pubmed:dateRevised
2007-12-3
pubmed:meshHeading
pubmed-meshheading:17785832-Animals, pubmed-meshheading:17785832-CD4-Positive T-Lymphocytes, pubmed-meshheading:17785832-CD8-Positive T-Lymphocytes, pubmed-meshheading:17785832-Cell Line, pubmed-meshheading:17785832-Cell Line, Tumor, pubmed-meshheading:17785832-Chlamydophila Infections, pubmed-meshheading:17785832-Chlamydophila pneumoniae, pubmed-meshheading:17785832-Cytotoxicity Tests, Immunologic, pubmed-meshheading:17785832-Epitopes, T-Lymphocyte, pubmed-meshheading:17785832-Female, pubmed-meshheading:17785832-Histocompatibility Antigens Class I, pubmed-meshheading:17785832-Immunity, Cellular, pubmed-meshheading:17785832-Intracellular Fluid, pubmed-meshheading:17785832-Mice, pubmed-meshheading:17785832-Mice, Inbred C57BL, pubmed-meshheading:17785832-Mice, Knockout, pubmed-meshheading:17785832-Peptides, pubmed-meshheading:17785832-T-Lymphocytes, Cytotoxic
pubmed:year
2007
pubmed:articleTitle
CD8+ T cell protective immunity against Chlamydia pneumoniae includes an H2-M3-restricted response that is largely CD4+ T cell-independent.
pubmed:affiliation
Department of Microbiology and Immunology, University of Texas Health Center, Tyler, TX 75708, USA.
pubmed:publicationType
Journal Article, Research Support, N.I.H., Extramural