title: OX40 ligation enhances cell cycle turnover of Ag-activated CD4 T cells in vivo.
abstract: OX40 costimulates T cells, increases activated T cell longevity, and promotes memory acquisition. T cells activated in vivo with agonist anti-OX40 and ovalbumin have a unique pattern of survival and cell division compared to control cells, but are able to respond to recall Ag equally well. BrdU incorporation shows that early cellular division rates of the anti-OX40-treated and the control groups are similar. Nevertheless, more BrdU(+) Ag-specific T cells accumulate in lymphoid tissue upon anti-OX40 administration. Thus, OX40 ligation does not necessarily lead to increased cell cycle entry, but promotes the accumulation of dividing cells. However, CFSE staining shows that OX40 ligation allows cells to progress through more cellular division cycles, while control cells stall or die. Moreover, OX40 ligation leads to a proportional decrease in apoptotic Ag-specific T cells. Thus, OX40 ligation boosts immunity by promoting an increase in the number cell cycles completed, thereby increasing the life span of Ag-activated CD4 T cells.
authors: Department of Microbiology, Oregon State University, 220 Nash Hall, Corvallis, Oregon 97331, USA.
authors: A R
authors: AR
authors: Weatherill
authors: J R
authors: JR
authors: Maxwell
authors: C
authors: C
authors: Takahashi
authors: A D
authors: AD
authors: Weinberg
authors: A T
authors: AT
authors: Vella
mesh_terms: D000818:Animals; D017209:Apoptosis; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D002453:Cell Cycle; D017635:Clonal Anergy; D005260:Female; D007117:Immunization, Secondary; D008213:Lymphocyte Activation; D051379:Mice; D008807:Mice, Inbred BALB C; D011971:Receptors, Immunologic / Q000378:metabolism*; D053262:Receptors, OX40; D018124:Receptors, Tumor Necrosis Factor; D018127:Tumor Necrosis Factor Receptor Superfamily, Member 7 / Q000378:metabolism*; D014611:Vaccination
chemical_list: D011971:Receptors, Immunologic; D053262:Receptors, OX40; D018124:Receptors, Tumor Necrosis Factor; C505717:Tnfrsf4 protein, mouse; D018127:Tumor Necrosis Factor Receptor Superfamily, Member 7