Improved activation toward primary colorectal cancer cells by antigen-specific targeting autologous cytokine-induced killer cells.

Adoptive therapy of malignant diseases with cytokine-induced killer (CIK) cells showed promise in a number of trials; the activation of CIK cells from cancer patients towards their autologous cancer cells still needs to be improved. Here, we generated CIK cells ex vivo from blood lymphocytes of colorectal cancer patients and engineered those cells with a chimeric antigen receptor (CAR) with an antibody-defined specificity for carcinoembryonic antigen (CEA). CIK cells thereby gained a new specificity as defined by the CAR and showed increase in activation towards CEA⁺ colon carcinoma cells, but less in presence of CEA⁻ cells, indicated by increased secretion of proinflammatory cytokines. Redirected CIK activation was superior by CAR-mediated CD28-CD3ζ than CD3ζ signaling only. CAR-engineered CIK cells from colon carcinoma patients showed improved activation against their autologous, primary carcinoma cells from biopsies resulting in more efficient tumour cell lysis. We assume that adoptive therapy with CAR-modified CIK cells shows improved selectivity in targeting autologous tumour lesions.

Restoring three-dimensional magnetic resonance angiography images with mean curvature motion.

OBJECTIVE: The management of neurovascular disease requires precise information on the cerebral vascular anatomy. Digital subtraction angiography (DSA) is the gold standard against which other imaging modalities have to be measured. To improve the quality of three-dimensional (3D) magnetic resonance angiography (MRA) images, we present a novel concept in 3D image analysis. METHODS: Five patients, harboring cerebral aneurysm, underwent DSA, computed tomography angiography (CTA) and MRA. MRA data were processed using a novel anisotropic curvature motion model. Three-dimensional reconstructions of CTA and MRA datasets were used for comparison. RESULTS: The 3D-reconstructed images accurately displayed all aneurysms. The anatomy of the anterior part of the circle of Willis was visualized reliably. The smoothened vessel surfaces enhanced the readability of the images. Regarding visual representation of the posterior part of the circle of Willis, the post-processed MRA showed the arterial segments less accurate than the standard modalities. CONCLUSIONS: This new approach is a promising tool for planning of neurovascular interventions and preoperative evaluation.

Simultaneous cytokine analysis by cytometric bead array for the detection of leukaemia-reactive T cells in patients with chronic myeloid leukaemia.

In order to detect T cells against several chronic myeloid leukaemia (CML)-associated antigens we used: (i) a novel T-cell assay [cytometric bead array (CBA)]; (ii) gamma-interferon enzyme-linked immunoSPOT (gamma-IFN-ELISpot); and (iii) tetramer staining in peripheral blood from CML patients. Peptide-specific cytokine release was detected by CBA in some patients, whereas standard gamma-IFN-ELISpot and tetramer staining were negative in the vast majority of cases. In CBA, peptide-specific cytokine release was predominantly tumour necrosis factor-alpha, raising questions about the responding cells and their functional status. CBA appears to be a new useful tool for the detection of leukaemia-reactive T cells.

T cell recognition of bcr/abl in healthy donors and in patients with chronic myeloid leukaemia.

In chronic myeloid leukaemia (CML), peptides from the fusion region of bcr3/abl2 are likely to play a role in anti-leukaemic T cell immunity. We investigated whether T cells that recognize bcr/abl fusion peptides could be detected in healthy donors and CML patients. T cell responses against bcr3/abl2 fusion peptides were analysed by gamma-interferon enzyme-linked immunospot assays after prestimulation of peripheral blood mononuclear cells in the presence of anti-CD3-antibodies and interleukin-2. Our results suggest that the T cell repertoire contains bcr3/abl2-reactive T cells in CML patients who are in cytogenetic remission, but also in some healthy individuals.

Cellular immunotherapy after autologous hematopoietic stem cell transplantation: experimental strategies and clinical experiences.

Recurrence of disease after autologous hematopoietic stem cell transplantation is at least partly due to contamination of the reinfused transplant with tumor cells, thereby limiting the clinical outcome after transplantation. On the other hand, immunological effector cells are capable of purging bone marrow transplants in vitro and of destroying disseminated tumor cells in vivo. Cellular immunotherapy subsequent to autologous stem cell transplantation is therefore expected to have a major impact on recurrence rates of the disease. In this review, we present various strategies utilizing immunologic effector cells for elimination of disseminated tumor cells and discuss the advantages and limitations of cellular immunotherapy after autologous hematopoietic stem cell transplantation.