Host-Based Th2 Cell Therapy for Prolongation of Cardiac Allograft Viability
Figure 4
Th2.R cell therapy plus cyclosporine reduces host T cell activation, induces a host Th2 phenotype, and reduces intra-cardiac allospecific T cells.
Rat allogeneic cardiac transplants were performed and assigned to one of eight treatment cohorts, including; 28-day daily cyclosporine A therapy [“CSA(28)”; engraftment control]; Th2.R adoptive cell therapy alone (“Th2.R”) at day 0 (D0), day-7 (D-7) or both (D-7+D0); 10-day, short-course CSA therapy alone [“CSA(10);” experimental control]; or a combination of short-course CSA plus Th2.R cell therapy [“CSA(10)+Th2.R”] at day 0 (D0), day-7 (D-7) or both (D-7+D0). (a) At day 28 post-transplant, transplant recipients were euthanized and splenocytes were harvested. The frequency of activated CD4+ and CD8+ T cells in each cohort at each organ site was then determined by flow cytometry (percent of CD4+ or CD8+ T cells that co-expressed CD25 in the absence of Foxp3 expression; results are mean ± SEM of 5 or 7 evaluated per cohort; *, indicates p<0.05). Splenocytes were harvested and subjected to either co-stimulation (b & c) or syngeneic and allogeneic APC stimulation (d & e; allospecific cytokine secretion is shown); resultant 24 h supernatants were then tested for cytokine content by Multiplex assay. (f) The frequency of activated CD4+ and CD8+ T cells in harvested cardiac tissue was determined by flow cytometry (percent of CD4+ or CD8+ T cells that co-expressed CD25 in the absence of Foxp3 expression; results are mean ± SEM of 7 evaluated per cohort; *, indicates p<0.05). (g) Intracardiac T cells were subjected to stimulation with allogeneic dendritic cells; resultant 24 h supernatants were then tested for cytokine content by Multiplex assay. (h) Survival of cardiac allografts between various cohorts is shown.