Generation of heterogeneous memory T cells by live attenuated tularemia vaccine in humans.
There is very limited evidence concerning the phenotype, function, and homing characteristics of memory T (T(M)) cells elicited by vaccination against intracellular bacteria in humans. Here we studied T(M) subsets elicited by exposure to Francisella tularensis in humans as a model of immunity to intracellular bacteria. To this end, T(M) cells were evaluated in two groups: (1) subjects immunized with live attenuated tularemia vaccine by skin scarification and (2) tularemia naturally infected subjects. In both groups the immune responses were mediated by CD4(+) and CD8(+) effector T(M) cells, mostly CD45RA(-)CD62L(-) and CD45RA(+)CD62L(-). Based on the expression of CD27, integrins alpha(4)/beta(7,) and alpha(4)/beta(1), it is likely that some of these T(M) cells have lytic potential and the ability to enter both mucosal and non-mucosal sites. Thus, regardless of whether by immunization or natural exposure, tularemia antigens elicited a broad spectrum of specific T(M) subsets with diverse homing characteristics.
Center for Vaccine Development, University of Maryland, 685 West Baltimore Street, HSF-1, Room# 480, Baltimore, MD 21201, USA. rmezghan@medicine.umaryland.edu
Rosangela
R
Salerno-Gonçalves
Matthew J
MJ
Hepburn
Sina
S
Bavari
Marcelo B
MB
Sztein
D000328:Adult; D000942:Antigens, Bacterial / Q000276:immunology; D001428:Bacterial Vaccines / Q000276:immunology*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D016022:Case-Control Studies; D002478:Cells, Cultured; D005604:Francisella tularensis / Q000276:immunology; D006801:Humans; D007111:Immunity, Cellular; D007156:Immunologic Memory; D007371:Interferon-gamma / Q000276:immunology; D007376:Interleukin-2 / Q000276:immunology; D008875:Middle Aged; D016176:T-Lymphocyte Subsets / Q000276:immunology*; D014406:Tularemia / Q000276:immunology / Q000517:prevention & control*; D014409:Tumor Necrosis Factor-alpha / Q000276:immunology; D014613:Vaccines, Attenuated / Q000276:immunology
D000942:Antigens, Bacterial; D001428:Bacterial Vaccines; C508594:IL2 protein, human; D007376:Interleukin-2; D014409:Tumor Necrosis Factor-alpha; D014613:Vaccines, Attenuated; D007371:Interferon-gamma