title: The early phase of human sepsis is characterized by a combination of apoptosis and proliferation of T cells.
abstract: OBJECTIVE
  T cell activation as well as unresponsiveness has been described in separate studies in sepsis. Our aim was to establish the coexistence of both T cell fate in human sepsis.
  
  
  METHODS
  This is a cross-sectional study of 48 patients presenting with severe sepsis or septic shock and 15 healthy controls. Cytofluorometric techniques were used to quantify T cell activation, apoptosis, proliferation, expression of costimulatory molecules, and cytokine secretion.
  
  
  RESULTS
  Patients with sepsis were characterized by a significant increase in the percentage of activated T cell subsets, as measured using CD69 marker, compared with healthy controls (P<.05). T cell proliferation as measured through Ki67 expression was obvious in infected patients for both CD4 and CD8 T cell subsets compared with controls (P ≤.006). T cell subset apoptosis as measured using Hoechst dye was also increased in infected patients compared with controls (P ≤.002). CD4 T cell proliferation was correlated with interleukin 2 secretion (R(2)=0.84, P<.001), whereas up-regulation of CD4 T cell apoptosis was correlated with CTLA-4 expression (R(2)=0.24, P=.001). No such similar relationship was observed for CD8(+) T cells.
  
  
  CONCLUSIONS
  Concomitant T cell proliferation and T cell apoptosis are observed in human sepsis, being related to a different pathway.
authors: Service d'Infectiologie, Centre Hospitalier Universitaire de Nice, France. roger.pm@chu-nice.fr
authors: Pierre-Marie
authors: PM
authors: Roger
authors: Hervé
authors: H
authors: Hyvernat
authors: Michel
authors: M
authors: Ticchioni
authors: Gaurav
authors: G
authors: Kumar
authors: Jean
authors: J
authors: Dellamonica
authors: Gilles
authors: G
authors: Bernardin
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017209:Apoptosis / Q000276:immunology; D049109:Cell Proliferation; D003430:Cross-Sectional Studies; D016207:Cytokines / Q000276:immunology; D005260:Female; D006801:Humans; D008213:Lymphocyte Activation / Q000276:immunology; D008297:Male; D008875:Middle Aged; D018805:Sepsis / Q000453:epidemiology / Q000276:immunology*; D012772:Shock, Septic / Q000453:epidemiology / Q000276:immunology*; D016176:T-Lymphocyte Subsets / Q000276:immunology; D013601:T-Lymphocytes / Q000502:physiology*; D015854:Up-Regulation / Q000276:immunology
chemical_list: D016207:Cytokines