Comment : Utopianism and Communitarianism

千葉大学公共研究センター21世紀プログラム「持続可能な福祉社会に向けた公共研究拠点

Demonstration of hemagglutination employing mBsAb (A) and pBsAb (B) against human red blood cells and <i>Listeria</i> cells.

<p>The wells contain a constant number of RBC (20 μl of 60% hematocrit) and <i>Listeria</i> cells (10³ cells) plus serial two-fold dilutions of BsAb. The spread pattern in the experimental series indicates positive hemagglutination through well 5 and 4 respectively for mBsAb and pBsAb incubated wells. The wells marked as a, b and c were incubated with anti-Lis Ab, anti-RBC Ab and a mixture of these two respectively. At least three independent experiments were performed for each sample and data are representative of three independent experiments with similar observations.</p

An Alternative Chemical Redox Method for the Production of Bispecific Antibodies: Implication in Rapid Detection of Food Borne Pathogens

<div><p>Bi-functional antibodies with the ability to bind two unrelated epitopes have remarkable potential in diagnostic and bio-sensing applications. In the present study, bispecific antibodies that recognize human red blood cell (RBC) and the food borne pathogen <i>Listeria monocytogenes</i> (<i>L. monocytogenes</i>) were engineered. The procedure involves initial reduction of a mixture of anti-RBC and anti-Listeria antibodies followed by gradual re-oxidation of the reduced disulphides. This facilitates association of the separated antibody chains and formation of hybrid immunoglobulins with affinity for the <i>L. monocytogenes</i> and human RBC. The bispecific antibodies caused the agglutination of the RBCs only in the presence of <i>L. monocytogenes</i> cells. The agglutination process necessitated the specific presence of <i>L. monocytogenes</i> and the red colored clumps formed were readily visible with naked eyes. The RBC agglutination assay described here provides a remarkably simple approach for the rapid and highly specific screening of various pathogens in their biological niches.</p></div

Detection of <i>Listeria monocytogenes</i> using agglutination assay in inoculated meat (beef, chicken and mutton) samples.

<p>mBsAbs as well as pBsAbs rendered agglutination of RBCs when incubated with <i>Listeria</i> inoculated meat. The wells marked as ‘B’ are controls lacking <i>Listeria</i> cells. At least three independent experiments were performed for each sample and data are representative of three independent experiments with similar observations.</p

<em>Aloe vera</em> Induced Biomimetic Assemblage of Nucleobase into Nanosized Particles

<div><h3>Aim</h3><p>Biomimetic nano-assembly formation offers a convenient and bio friendly approach to fabricate complex structures from simple components with sub-nanometer precision. Recently, biomimetic (employing microorganism/plants) synthesis of metal and inorganic materials nano-particles has emerged as a simple and viable strategy. In the present study, we have extended biological synthesis of nano-particles to organic molecules, namely the anticancer agent 5-fluorouracil (5-FU), using <em>Aloe vera</em> leaf extract.</p> <h3>Methodology</h3><p>The 5-FU nano- particles synthesized by using <em>Aloe vera</em> leaf extract were characterized by UV, FT-IR and fluorescence spectroscopic techniques. The size and shape of the synthesized nanoparticles were determined by TEM, while crystalline nature of 5-FU particles was established by X-ray diffraction study. The cytotoxic effects of 5-FU nanoparticles were assessed against HT-29 and Caco-2 (human adenocarcinoma colorectal) cell lines.</p> <h3>Results</h3><p>Transmission electron microscopy and atomic force microscopic techniques confirmed nano-size of the synthesized particles. Importantly, the nano-assembled 5-FU retained its anticancer action against various cancerous cell lines.</p> <h3>Conclusion</h3><p>In the present study, we have explored the potential of biomimetic synthesis of nanoparticles employing organic molecules with the hope that such developments will be helpful to introduce novel nano-particle formulations that will not only be more effective but would also be devoid of nano-particle associated putative toxicity constraints.</p> </div

Cytotoxic effect of 5-FU nano-particles.

<p>Against (<b>A</b>) HT-29 and (<b>B</b>) Caco-2 cell lines. MTT assay was used to determine the differential cytotoxicity of 5-FU nano-particles against both cell lines. Cells were dispensed at the density of 5×10⁴ cells per well in U-bottom 96 well plates in triplicate, and treated with increasing concentration of various 5-FU nano formulations. After 48 h of incubation, 20 µl of MTT reagent was added and plate was further incubated for 48 h. It was followed by addition of 100 µl of lysis buffer. The plates were further incubated for 2 hr and absorbance was read at 570 nm.</p

Effect of 5-FU nano-particles on expression of pro/anti apoptotic factors in Caco-2 cell line.

<p>Cell lysate was prepared as described in Methodology and analyzed for protein expression using specific antibodies. To quantify equal loading, the membranes were also probed with β-actin antibody. The intensity of bands was quantified using image analysis software on an image gel documentation system. Lane 1, RPMI only; Lane 2, <i>Aloe vera</i> leaf extract only; Lane 3, 5-FU only; Lane 4, 5-FU nano-particles prepared by mixing of 5-FU (10⁻³ M) solution with 3 ml of <i>Aloe vera</i> extract and Lane 5, 5-FU nano-particles prepared by mixing of 5-FU (10⁻³ M) solution with 5 ml of <i>Aloe vera</i> extract.</p

Schematic agglutination representation of erythrocytes and <i>Listeria monocytogenes</i> cells mediated by bispecific antibodies.

<p>Schematic agglutination representation of erythrocytes and <i>Listeria monocytogenes</i> cells mediated by bispecific antibodies.</p

Bispecific antibody mediated haemagglutination.

<p>mBsAb (<b>A</b>) as well as pBsAb (<b>B</b>) rendered agglutination of RBCs and <i>Listeria</i> cells on a glass slide. A given volume (50 μl of 200 ng/ml) of BsAb specific against both RBCs and <i>Listeria</i> cell surface Ag was mixed with <i>Listeria</i> cells-negative (<b>Aa, Ba</b>) or <i>Listeria</i> cells-positive (<b>Ab, Bb</b>). After 1 hr of incubation, the RBC agglutination results were observed under a microscope (right panel; magnification, 20X). At least three independent experiments were performed for each sample and data are representative of three independent experiments with similar observations.</p

Ball and socket model of 5-FU nano-particles.

<p>(<b>A</b>) Proposed structure of 5-FU nano-particles, (<b>B</b>) Simulated molecular model of 5-FU nanoparticle assembly using ChemDraw software.</p