title: Modelling T-cell memory by genetic marking of memory T cells in vivo.
abstract: Immunological memory is the ability of the immune system to respond with enhanced vigour to pathogens that have been encountered in the past. Following infection or immunization, most effector T cells undergo apoptotic cell death, but a small fraction of these cells, proportional to the early antigen load and initial clonal burst size, persist in the host as a stable pool of memory T cells. The existence of immunological memory has been recognized for over 2,000 years, but our understanding of this phenomenon is limited, primarily because memory lymphocytes cannot be unequivocally identified as they lack specific, permanent markers. Here we have developed a transgenic mouse model system whereby memory T cells and their precursors can be irreversibly marked with a reporter gene and thus can be unambiguously identified. Adoptive transfer of marked CD8+ T cells specific for lymphocytic choriomeningitis virus protected naive recipients following viral challenge, demonstrating that we have marked memory T cells. We also show that cytotoxic effector lymphocytes that develop into memory T cells can be identified in the primary response.
authors.affiliation: Department of Biology, Massachusetts Institute of Technology, Cambridge 02139, USA.
authors.forename: J
authors.initials: J
authors.lastname: Jacob
authors.forename: D
authors.initials: D
authors.lastname: Baltimore
mesh_terms: D019264:Adoptive Transfer; D000469:Alkaline Phosphatase / Q000096:biosynthesis / Q000235:genetics; D000818:Animals; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology / Q000637:transplantation; D003601:Cytotoxicity Tests, Immunologic; D017930:Genes, Reporter; D005819:Genetic Markers; D053804:Granzymes; D006801:Humans; D007156:Immunologic Memory; D016130:Immunophenotyping; D019426:Integrases / Q000235:genetics; D008213:Lymphocyte Activation; D008216:Lymphocytic Choriomeningitis / Q000276:immunology; D008217:Lymphocytic choriomeningitis virus / Q000276:immunology; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D011401:Promoter Regions, Genetic; D012697:Serine Endopeptidases / Q000235:genetics; D013154:Spleen / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology*; D014764:Viral Proteins
chemical_list: D005819:Genetic Markers; D014764:Viral Proteins; C045073:Cre recombinase; D019426:Integrases; D000469:Alkaline Phosphatase; C509213:GZMB protein, human; D053804:Granzymes; C509214:Gzmb protein, mouse; D012697:Serine Endopeptidases