title: Gamma irradiation or CD4+-T-cell depletion causes reactivation of latent Salmonella enterica serovar Typhimurium infection in C3H/HeN mice.
abstract: Upon infection with Salmonella, a host develops an immune response to limit bacterial growth and kill and eliminate the pathogen. Salmonella has evolved mechanisms to remain dormant within the body, only to reappear (reactivate) at a later time when the immune system is abated. We have developed an in vivo model for studying reactivation of Salmonella enterica serovar Typhimurium infection in mice. Upon subcutaneous infection, C3H/HeN (Ity(r)) mice showed an increase in bacterial numbers in livers and spleens, which reached a peak on day 19. After full recovery from the infection, these mice were irradiated or depleted of CD4(+) T cells. The mice displayed a secondary infection peak in livers and spleens with a course similar to that of the primary infection. We concluded that CD4(+) T cells are involved in active suppression of S. enterica serovar Typhimurium during latency. The role of CD4(+) T cells during primary infection with S. enterica serovar Typhimurium is well established. This is the first study to describe a role of CD4(+) T cells during the latent phase of S. enterica serovar Typhimurium infection.
authors.affiliation: Department of Infectious Diseases, Leiden University Medical Center, PO Box 9600, 2300 RC Leiden, The Netherlands.
authors.forename: Angela
authors.initials: A
authors.lastname: van Diepen
authors.forename: Joke S
authors.initials: JS
authors.lastname: van de Gevel
authors.forename: Margaretha M
authors.initials: MM
authors.lastname: Koudijs
authors.forename: Ferry
authors.initials: F
authors.lastname: Ossendorp
authors.forename: Henry
authors.initials: H
authors.lastname: Beekhuizen
authors.forename: Riny
authors.initials: R
authors.lastname: Janssen
authors.forename: Jaap T
authors.initials: JT
authors.lastname: van Dissel
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D015704:CD4 Antigens; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D005720:Gamma Rays; D008212:Lymphocyte Depletion; D051379:Mice; D008809:Mice, Inbred C3H; D011827:Radiation; D012481:Salmonella Infections, Animal / Q000276:immunology* / Q000382:microbiology / Q000503:physiopathology; D012486:Salmonella typhimurium / Q000276:immunology / Q000472:pathogenicity* / Q000502:physiology*
chemical_list: D000907:Antibodies, Bacterial; D015704:CD4 Antigens