Evaluation of tumor immunity in patients with ovarian cancer after immunoscintigraphy in a long-term follow-up

Curcumin-mediated photodynamic inactivation (PDI) against DH5α contaminated in oysters and cellular toxicological evaluation of PDI-treated oysters

The objective of this study was to evaluate the bactericidal effect of curcumin (CUR)-mediated photodynamic inactivation (PDI) against Escherichia coli DH5α in vitro and in oysters, then further investigate the edible security of PDI-treated oysters based on cellular toxicological methods. First, DH5α cells were irradiated by a 470 nm LED light source with an energy density of 3.6 J/cm². Colony forming units (CFU) were counted and the viability of DH5α cells was calculated after treatment with CUR-mediated PDI. Intracellular production of reactive oxygen species (ROS) was studied by measuring the fluorescence of 2, 7-dichlorofluorescein (DCF) using a flow cytometry. Membrane permeability was measured using confocal laser scanning microscopy (CLSM) with propidium iodide (PI) staining. After that, the bactericidal effect of CUR-mediated PDI was evaluated in oysters which were pre-contaminated with DH5α cells. Finally, cellular toxicology of PDI-treated oysters was evaluated through morphological observation, 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay, DNA ladder assay, and nuclear staining. Results showed that the viability of DH5α was significantly decreased in a CUR concentration-dependent manner and resulted in an approximately 3.5-log reduction at the concentration of 20 μM. After treatment with CUR-mediated PDI (20 μM, 3.6 J/cm²), the ROS level in DH5α cells and the membrane permeability markedly increased. Our data demonstrated that CUR-mediated PDI had a good decontamination effect against DH5α contaminated in oysters. After incubation with PDI-treated oysters, fibroblasts L929 cell morphology, MTT absorbance and cell apoptosis had no obvious changes. Our findings preliminarily demonstrated that CUR-mediated PDI-treated oysters had no cytotoxicity to fibroblasts.

Induction of CA125-specific B and T cell responses in patients injected with MAb-B43.13--evidence for antibody-mediated antigen-processing and presentation of CA125 in vivo

The murine monoclonal anti-CA125 antibody MAb-B43.13 has previously been administered as an immunoscintigraphic agent in order to monitor recurrence of ovarian cancer in patients, and a long-term follow-up demonstrated a survival benefit for these patients. The clinical benefit was initially attributed to the activation of the idiotypic network. The objective of this study was to investigate the role of CA125-MAb-B43.13 immune complex formation on the induction of CA125-specific immune responses. Analysis of patient serum samples from pharmacokinetic studies demonstrated that the antibody forms immune complexes with CA125 in circulation within 30 minutes of injection. Induction of humoral and cellular anti-CA125 responses correlated with the amount of circulating CA125 antigen present at time of antibody injection. Subsequent to the injection of MAb-B43.13, the patients generated anti-CA125 antibodies that were directed against various epitopes on the antigen and were not restricted to the specific epitope recognized by MAb-B43.13. The generation of CA125-specific B and T cell responses after MAb-B43.13 injection correlated with improved survival. The influence of circulating CA125 for the induction of CA125-specific immune responses and the multi-epitopic nature of the human anti-CA125 antibodies suggest that the majority of these antibodies were not induced via the idiotypic network but by the autologous antigen itself. Since antibody and T cell responses to CA125 were not present before injection of MAb-B43.13, it is hypothesized that complex formation of MAb-B43.13 with circulating antigen triggers the induction of CA125-specific immune responses.