title: T-cell activation, proliferation, and memory after cardiac transplantation in vivo.
abstract: OBJECTIVE
  To study the response of alloantigen (H2Kb)-specific T cells to a H2b+ cardiac allograft in vivo.
  
  
  BACKGROUND
  The response of T cells to alloantigen has been well characterized in vitro but has proved more difficult to assess in vivo. The aim of these experiments was to develop a model of T-cell-mediated rejection where the response of T cells after transplantation of a cardiac allograft could be followed in vivo.
  
  
  METHODS
  Purified CD8+ T cells from H2Kb-specific TCR transgenic mice (BM3; H2k) were adoptively transferred into thymectomized, T-cell-depleted CBA/Ca (H2k) mice. These mice were then transplanted with a H2Kb+ cardiac allograft. Using four-color flow cytometry, the proliferative response, modulation of activation markers, and potential cytokine production of the H2Kb-specific T cells was assessed after transplantation.
  
  
  RESULTS
  Consistent rejection of H2Kb+ cardiac allografts required the transfer of at least 6 x 10(6) CD8+ H2Kb-specific T cells. Short-term analyses revealed that the transgenic-TCR+/ CD8+ T cells proliferated and became activated after transplantation of an H2Kb+ cardiac allograft. Fifty days after transplantation, the transgenic-TCR+/CD8+ T cells remained readily detectable, bore a predominantly memory phenotype (CD44hi), and rapidly produced interleukin 2 and interferon-gamma on in vitro restimulation.
  
  
  CONCLUSIONS
  These data show that the activation of alloantigen-specific T cells can be followed in vivo in short-term and long-term experiments, thereby providing a unique opportunity to study the mechanisms by which T cells respond to allografts in vivo.
authors: Nuffield Department of Surgery, John Radcliffe Hospital, Oxford, United Kingdom.
authors: N D
authors: ND
authors: Jones
authors: A
authors: A
authors: Van Maurik
authors: M
authors: M
authors: Hara
authors: B J
authors: BJ
authors: Gilot
authors: P J
authors: PJ
authors: Morris
authors: K J
authors: KJ
authors: Wood
mesh_terms: D000818:Animals; D015703:Antigens, CD / Q000096:biosynthesis; D002455:Cell Division; D016027:Heart Transplantation / Q000276:immunology*; D007156:Immunologic Memory; D008213:Lymphocyte Activation; D051379:Mice; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D011948:Receptors, Antigen, T-Cell / Q000096:biosynthesis; D013601:T-Lymphocytes / Q000166:cytology / Q000276:immunology*
chemical_list: D015703:Antigens, CD; D011948:Receptors, Antigen, T-Cell