Migration patterns of nonspecifically activated versus nonactivated nonhuman primate T lymphocytes:: Preferential homing of activated autologous CD8+ T cells in the rectal mucosa

Adoptive cell transfer may be a successful strategy in anticancer therapy and its therapeutic efficiency depends on the access of transferred cells to the tumor site and their persistence in vivo. Nevertheless, the migration properties of autologous in vitro-activated T cells in primates are largely unknown. Here, we established the long-term tracking of T-cell migration into various compartments of rhesus macaques as a preclinical model for the evaluation of T-cell-based immunotherapy. Peripheral blood mononuclear cells from 3 to 4 rhesus macaques were activated with anti-CD3/anti-CD28 or not, labeled with carboxyfluorescein diacetat succinimidyl ester, and reinjected intravenously into the donor animals. Blood samples, lymph node biopsies, and mucosal biopsies (duodenum, rectum) were collected at various time points and analyzed by flow cytometry for the presence of the reinjected T cells. We demonstrate that nonspecific in vitro activation changes the in vivo migratory behavior of T cells and provokes a preferential migration of CD8(+) T cells to the rectum. Nonspecifically activated transferred CD4(+) T cells were found in much lower frequencies at this site and also in other compartments. Thus, our results indicate an imbalanced distribution of autologous CD8(+) and CD4(+) T cells in various compartments that is more apparent when T cells are activated before the transfer. The migratory behavior of in vitro-expanded, autologously transferred T cells can, therefore, influence the clinical outcome of adoptive cell transfer.