254. Vaccination of Recurrent Glioma Patients with Tumour Lysate-Pulsed Dendritic Cells Elicits Immune Responses: Results of a Clinical Phase I/II Trial

In this Phase I/II trial, the patient's peripheral blood dendritic cells were pulsed with an autologous tumour lysate of the glioma. Fourteen patients with glioblastoma and 4 patients with anaplastic glioma, ranging in age from 20 to 73 years, participated in this study. The mean numbers of vaccinations of tumour lysate-pulsed dendritic cells were 4.8 times intradermally close to a cervical lymph node, and 4.2 times intratumourally via an Ommaya reservoir. The percentage of CD56-positive cells in the peripheral blood lymphocytes increased after immunization. There were 1 partial response, 2 minor responses and 7 no change cases evaluated by radiological findings. Dendritic cell vaccination elicited T-cell-mediated antitumour activity, as evaluated by ELISPOT assay after vaccination in 2 of 5 tested patients. Three patients showed DTH reactivity to the autologous tumour lysate, two of these had a minor clinical response, and two had an increased ELISPOT result. Intratumoural CD4 and CD8 T-cell infiltration was detected in two patients who underwent re-operation after vaccination. This study demonstrated the safety and antitumour effects of autologous tumour lysate-pulsed dendritic cell therapy for patients with malignant glioma.