Number of treatment cycles influences development of cytotoxic T cells in metastatic breast cancer patients - a phase I/II study.

The influence of the number of apheresis-stimulation-infusion(s) cycles, and the time in culture before the infusion (one vs. two weeks), on the generation of tumor antigen-specific cytotoxic T-lymphocytes (CTL) was investigated in a phase I/II clinical adoptive immunotherapy trial. Two previously treated metastatic breast cancer patients with no evidence of disease, in complete remission (CR), were enrolled. Each apheretic peripheral blood mononuclear cell (PBMC) sample was stimulated twice with MUC-1 before infusion back into the patients. Killer T-cells responses against MUC-1-expressing MCF-7 (CTL), nonspecific natural killer (NK) and lymphokine-activated killer (LAK) target cell lines, as well as, cytokine production were measured before each infusion. Patients received 2 infusions per month for 4 months. There were no tumor recurrences or toxicity. CTL, NK and LAK cells, type 1 cytokine, gamma-interferon (G-INF), and CD4(+) and CD8(+) memory T-lymphocytes were initially generated, produced or induced, respectively, and then declined. The CTL, NK and LAK cells were only induced at the first infusion of the first month. Thus, maintaining PBMC in culture longer than the first infusion was of no benefit with regards to retaining functional killer T-cells. In conclusion, this study implies that one treatment is optimal.

Tumor burden influences cytotoxic T cell development in metastatic breast cancer patients--a phase I/II study.

The influence of tumor burden on the generation of tumor antigen-specific cytotoxic T-lymphocytes (CTL) was investigated in a phase I/II clinical adoptive immunotherapy trial. Four previously treated metastatic breast cancer patients, two with macroscopic disease and two with no evidence of disease, in complete remission (CR), were enrolled. Each apheretic peripheral blood mononuclear cell (PBMC) sample was stimulated twice with MUC-1 before infusion back into the patients. CTL responses against MCF-7 cell line and cytokine production were measured before infusion. Patients received two monthly CTL infusions and were monitored for toxicity, tumor response as well as tumor marker levels. The CTL generated from patients with high tumor burdens had less cytokine production and lower cytotoxicity of MCF-7 than the CTL of patients in CR. The differences between the two groups were observed after the two MUC1 in vitro stimulations of the cells obtained in first apheresis. This difference increased after the two MUC1 stimulations of the cells obtained in the second apheresis. The cytotoxicity function was sustained from the first infusion to the second apheresis only for the patients in CR. This suggests that tumor burden had an inverse effect on the function of the generated CTL.

Initial management of immune thrombocytopenic purpura in adults: a randomized controlled trial comparing intermittent anti-D with routine care.

We conducted a randomized clinical trial in adults with a new diagnosis of ITP and a platelet count <30000/muL to test the hypothesis that initial intermittent treatment with anti-D may avoid or defer the need for splenectomy when compared to current routine care (glucocorticoid treatment, followed by splenectomy). Splenectomy was to be performed in the anti-D group if patients failed to respond to three consecutive anti-D treatments given within 10 days. The incidences of splenectomy were 14 of 37 (38%) in the routine care group and 14 of 33 (42%) in the anti-D group (absolute risk reduction = 4.6% in favor of the routine care group, 95% CI, -18.4 to 27.6%). However, splenectomy was performed prematurely, not according to the protocol, in 11 of 14 patients in the anti-D group. The median time to splenectomy was 36 days (range, 9-78) in the routine care group and 112 days (range, 19-558) in the anti-D group (P = 0.045 at 100 days after randomization, P = 0.840 at 1 year after randomization, using log-rank analysis). Patients in the anti-D group were treated with prednisone for fewer days (70 days) compared to the routine care group (112 days, P = 0.01). No major bleeding events occurred. In this study, initial treatment of patients with intermittent anti-D initially deferred splenectomy. Whether our aggressive regimen of anti-D could have prevented splenectomy if it had been adhered to in all patients remains uncertain. However, compliance with this anti-D regimen was not feasible for many patients and/or their physicians.

Adoptive immunotherapy of mucin1 expressing adenocarcinomas with mucin1 stimulated human peripheral blood mononuclear cells.

Mucin1 stimulated hematopoietic mononuclear cells (M1SHMC) from patients with breast cancer, adoptively transferred to non-obese diabetic, severe combined immunodeficient (NOD SCID) mice, extended survival in a therapy model of gross adenocarcinoma and prevented tumor growth in a model of minimal disease. M1SHMC exhibited specific lysis of a human breast adenocarcinoma cell line expressing mucin1, MCF-7 and produced interferon gamma. M1SHMC were injected intraperitoneally (IP) in NOD SCID mice after gross, palpable tumors appeared after MCF-7 were injected subcutaneously (SC). Survival was increased as compared to no M1SHMC controls. However tumors eventually regrew in all mice. To determine whether minimal disease (MD) could be controlled, NOD SCID were injected with MCF-7 cells, and on the same day, injected IP with M1SHMC. The M1SHMC injected mice were protected from tumor growth. These results imply that M1SHMC can prolong survival, but not cure NOD SCID mice bearing gross palpable adenocarcinomas. However in a minimal disease model tumor growth was prevented.