Tamar Yechezkel

A two-step strategy to visually identify molecularly imprinted polymers for tagged proteins

A practical and relatively simple method to identify molecularly imprinted polymers capable of binding proteins via the molecular tagging (epitope-like) approach has been developed. In our two-step method, we first challenge a previously obtained anti-tag molecularly imprinted polymer with a small molecule including the said tag of choice (a biotin derivative as shown here or other) connected to a linker bound to a second biotin moiety. An avidin molecule partially decorated with fluorescent labels is then allowed to bind the available biotin derivative associated with the polymer matrix. At the end of this simple process, and after washing off all the low-affinity binding molecules from the polymer matrix, only suitable molecularly imprinted polymers binding avidin through its previously acquired small molecule tag (or epitope-like probe, in a general case) will remain fluorescent. For confirmation, we tested the selective performance of the anti-biotin molecularly imprinted polymer binding it to biotinylated alkaline phosphatase. Residual chemical activity of the enzyme on the molecularly imprinted polymer solid support was observed. In all cases, the corresponding nonimprinted polymer controls were inactive.

Palliative treatment of obstructive esophageal cancer by vascular targeted photodynamic therapy (VTP): Preclinical study in orthotopic rat model.

59 Background: Vascular targeted photodynamic therapy (VTP) based on local sensitization of circulating WST11 (Pd-bacteriochlorophyll), enables effective focal ablation of solid tumors. WST11 clears from the circulation with t1/2 ~40 min (in humans) and does not accumulate in tissues which assures high level of safety and minimal adverse effects. Here we evaluate WST11-VTP for the treatment of obstructive esophageal cancer aiming at developing clinically relevant protocol. Methods: Using endoscopy guided procedure rat esophageal cancer cells (JA) were implanted in the mid esophagus. Following intravenous infusion of WST11, established tumors were illuminated by cylindrical fiber using the same endoscope sleeve. Safety and efficacy were evaluated by monitoring animal weight shift and histology of treated esophageal tissues. Treated animals included control (light/no WST11 or WST11/no light), WST11-VTP and WST11-VTP following treatment with bevacizumab at day -3. Results: WST11-VTP on esophageal tissues res...