Intracellular interferon-γ staining analysis of donor-specific T-cell responses in liver transplant recipients.

OBJECTIVE: Biomarkers that accurately reflect, detect, and/or predict detrimental immune responses to grafts are important in organ transplantation. We established a new detection method for alloreactive T cells on the basis of intracellular staining for interferon (IFN)-γ, using CD40-activated B cells as stimulators, and assessed temporal changes in alloreactive T-cell frequencies in patients who received liver transplantation. METHODS: Peripheral blood mononuclear cells and CD40-activated B cells were used as responder and stimulator cells, respectively. The responder cells were cultured with the stimulator cells for 7 days, restimulated for 5 hours, and flow cytometrically tested by intracellular staining for IFN-γ. RESULTS: The relative postoperative-preoperative ratio of donor-specific CD8+ T cells in the nonrejection group was significantly lower than that in the rejection group and found to be <1 in most individuals of the group throughout the postoperative periods, indicating an induction of donor-specific suppression of the CD8+ T-cell responses. In contrast, such differences were not found in the donor-specific CD4+ T cells. These results suggest that the relative postoperative-preoperative ratio of the donor-specific CD8+ T cells is a good indicator of graft rejection. CONCLUSION: We established a new flow cytometric method for the detection of alloreactive T cells by intracellular staining for IFN-γ, using CD40-activated B cells as stimulator cells. Using this system, we found that the relative postoperative-preoperative ratio of the donor-specific CD8+ T cells is a possible evaluative indicator of the risk for graft rejection.

[Neoadjuvant chemotherapy for advanced gastric cancer with para-aortic lymph node metastasis].

Neoadjuvant chemotherapy was applied to patients with advanced gastric cancer and confirmed para-aortic lymph node metastasis. Subjects were 7 patients. The response to the neoadjuvant chemotherapy was a PR in 5 cases, MR in 2 cases for the primary lesion and CR in 2 cases PR in 5 cases for the para-aortic lymph node metastasis. The grades of histological response assessed on the resected specimen were Grade 0 in three cases, Grade 1a in one, Grade 1b in one and Grade 2 in two. While there was no significant difference in survival rate between patient groups with and without neoadjuvant chemotherapy, the 2-year survival rate in patients with neoadjuvant chemotherapy was a good 42.9%, compared with 10% in patients groups without neoadjuvant chemotherapy. It is concluded that a better prognosis can be expected for advanced gastric cancer patients with neoadjuvant chemotherapy.