Cytokine-induced killer cells (CIK cells), coexpressing CD3 and CD56, can be expanded from peripheral blood mononuclear cells by the timed addition of interferon-c (IFN-c), IL-2 and OKT3. The effects of CIK cells on primary, autologous CLL cells are described. We used MACS to separate CD3 1 cells for expansion of CIK cell effectors and CD19 1 targets from peripheral blood of 16 CLL patients. Apoptosis was assessed by measuring annexinV staining in CLL cells. After incubation of autologous CIK with CLL, specific apoptosis in CLL cells was 15%. Coincubation with irradiated CIK cells for 48 hr before adding vital CIK cells resulted in an increased ICAM-1 expression on CLL cells and an increase in apoptosis of CLL targets (30%). These effects were mediated by IFN-c secretion of CIK cells. In addition to their direct cytotoxic effect, CIK cells secrete IFN-c that modulates the expression of adhesion molecules on CLL cells, and this enhances apoptosis induction by cytotoxic effector cells. ' 2006 Wiley-Liss, Inc.

Objective Elevated pre-operative C-reactive protein (CRP) serum values have been reported to be associated with poor overall survival for patients with pancreatic neuroendocrine neoplasms (pNEN). The aim of this study was to identify mechanisms linking CRP to poor prognosis in pNEN. Methods The malignant properties of pNENs were investigated using the human pNEN cell-lines BON1 and QGP1 exposed to CRP or IL-6. Analyses were performed by ELISA, Western blot, flow cytometry and immunocytochemistry as well as invasion and proliferation assays. To compare cytokine profiles and CRP levels, 76 serum samples of pNEN patients were analyzed using Luminex technology. In parallel, the expression of CRP and growth signaling pathway proteins was assessed on cell lines and paraffin-embedded primary pNEN. Results In BON1 and QGP1 cells, inflammation (exposure to IL-6) significantly upregulated CRP expression and secretion as well as migratory properties. CRP stimulation of BON1 cells increased IL-6 secretion and invasion. This was accompanied by activation/phosphorylation of the ERK, AKT and/or STAT3 pathways. Although known CRP receptors – CD16, CD32 and CD64 – were not detected on BON1 cells, CRP uptake of pNEN cells was shown after CRP exposure. In patients, increased pre-operative CRP levels (≥5 mg/L) were associated with significantly higher serum levels of IL-6 and G-CSF, as well as with an increased CRP expression and ERK/AKT/STAT3 phosphorylation in pNEN tissue. Conclusion The malignant properties of pNEN cells can be stimulated by CRP and IL-6 promoting ERK/AKT/STAT pathways activation as well as invasion, thus linking systemic inflammation and poor prognosis.

Due to their dual binding capacity, bispecific antibodies (bsAb) can be used to cross-link cytotoxic effector cells with malignant targets and may thereby improve adoptive immunotherapy. In this study, the development and preclinical testing of the quadroma-derived bsAb HD37xT5.16 of the specificity CD19xCD5 is reported. Effector cells used were a population of ex vivo expanded and activated T cells called cytokine-induced killer (CIK) cells expressing CD5. When combined with CIK cells, the cytolytic potency of HD37xT5.16 against CD19 positive B cell lymphoma lines was comparable to that observed with a previously described CD19xCD3 bsAb. Further on, we could demonstrate that bsAb CD19xCD5, in contrast to its CD3-binding counterpart, does not induce proliferation of resting T cells and causes only little activation-induced cell death. Therefore, this novel bsAb binding effector T cells via CD5 may be particularly useful in combination with adoptive transfer of ex vivo activated T cells, e.g., in the setting of adoptive immunotherapy after allogeneic stem cell transplantation. The in vitro studies outlined here support the experimental use of bsAb HD37xT5.16 in preclinical in vivo models for evaluation of its safety and efficacy profile.