title: Mycobacterium tuberculosis-specific and MHC class I-restricted CD8+ T-cells exhibit a stem cell precursor-like phenotype in patients with active pulmonary tuberculosis.
abstract: The nature and longevity of the T-cell response directed against Mycobacterium tuberculosis (MTB) are important for effective pathogen containment. We analyzed ex vivo the nature of MTB antigen-specific T-cell responses directed against the MTB secreted antigens Rv0288, Rv1886c, Rv3875, the antigens Rv2958c, Rv2957, and Rv0447c (intracellular, non-secreted enzymes) in blood from Korean patients with active tuberculosis (TB). MTB-specific T-cell function was defined by intracellular cytokine production (interleukin (IL)-2, interferon gamma, tumour necrosis factor alpha, and IL-17) and by multimer-guided (HLA-A*02:01 and HLA-A*24:02) analysis of epitope-specific CD8+ T-cells, along with phenotypic markers (CD45RA and CCR7), CD107a, a marker for degranulation, and CD127 co-staining for T-cell differentiation and homing. Cytokine production analysis underestimated the frequencies of MTB antigen-specific T-cells defined by major histocompatibility complex (MHC) class I-peptide multimer analysis. We showed that MTB antigen-specific CD8+ T-cells exhibit a distinct marker profile associated with the nature of the MTB antigens, i.e., Rv0288, Rv1886c, and Rv3875-reactive T-cells clustered in the precursor T-cell compartment, whereas Rv2958c, Rv2957, and Rv0447c-reactive T-cells were associated with the terminally differentiated T-cell phenotype, in the patient cohort. Rv0288, Rv1886c, and Rv3875-specific CD8+ T-cells were significantly enriched for CD107a+ T-cells in HLA-A*02:01 (p<0.0001) and HLA-A*24:02 (p=0.0018) positive individuals, as compared to Rv2958c, Rv2957, and Rv0447c antigens. CD127 (IL-7 receptor)-expressing T-cells were enriched in HLA-A*02:01-positive individuals for the Rv0288, Rv1886c, and Rv3875 specificities (p=0.03). A high proportion of antigen-specific T-cells showed a precursor-like phenotype (CD45RA+CCR7+) and expressed the stem cell-associated markers CD95 and c-kit. These data show that MTB-specific T-cells can express stem cell-like features; this is associated with the nature of the MTB antigen and the genetic background of the individual.
authors: Centre for Allogeneic Stem Cell Transplantation (CAST), Karolinska University Hospital, Stockholm, Sweden.
authors: Rebecca
authors: R
authors: Axelsson-Robertson
authors: Catholic University of Korea, Seoul St. Mary's Hospital, Seoul, South Korea.
authors: Ji Hyeon
authors: JH
authors: Ju
authors: Catholic University of Korea, Seoul St. Mary's Hospital, Seoul, South Korea.
authors: Ho-Youn
authors: HY
authors: Kim
authors: Division of Infection and Immunity, University College London, and NIHR Biomedical Research Center at UCLHospital, London, United Kingdom.
authors: Alimuddin
authors: A
authors: Zumla
authors: Centre for Allogeneic Stem Cell Transplantation (CAST), Karolinska University Hospital, Stockholm, Sweden; Division of Therapeutic Immunology (TIM), F79, Department of Laboratory Medicine (LABMED), Hälsovägen, Karolinska University Hospital Huddinge, SE-14186 Huddinge, Sweden. Electronic address: markus.maeurer@ki.se.
authors: Markus
authors: M
authors: Maeurer
mesh_terms: D000328:Adult; D000368:Aged; D000942:Antigens, Bacterial / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D016207:Cytokines / Q000378:metabolism; D018984:Epitopes, T-Lymphocyte; D005260:Female; D015395:Histocompatibility Antigens Class I / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D009169:Mycobacterium tuberculosis / Q000276:immunology*; D010641:Phenotype; D013234:Stem Cells / Q000276:immunology; D014397:Tuberculosis, Pulmonary / Q000276:immunology*; D055815:Young Adult
chemical_list: D000942:Antigens, Bacterial; D016207:Cytokines; D018984:Epitopes, T-Lymphocyte; D015395:Histocompatibility Antigens Class I
keywords: CD8+ T-cells; Mycobacterium tuberculosis; T-cell differentiation; Tetramer