Growth curves of the HeLa tumors and CNE2 tumors of a large size treated with KR-<i>E</i>. <i>coli</i>.

<p>The black line indicates the volume change of tumors injected with <i>E</i>. <i>coli</i> that expressed no KillerRed. The red dotted line indicates the volume change of CNE2 tumors (volume = 150 mm³) injected with <i>E</i>. <i>coli</i> that expressed KillerRed. The red full line indicates the volume change of HeLa tumors injected with <i>E</i>. <i>coli</i> that expressed KillerRed. All tumors were irradiated at the same dose on the day 7. Before treatment, ^♦p > 0.05 (rank sum test), error bars indicate SEM. After treatment, *P< 0.01 (rank sum test), error bars indicate SEM.</p

Superoxide is released from KR-<i>E</i>. <i>coli</i> upon orange light irradiation.

<p><b>a,</b> Ordinary light image (left) and fluorescence image (right) of a KR-<i>E</i>. <i>coli</i> suspension observed under a microscope. Bar, 10 m. <b>b,</b> The production of superoxide by the irradiation of KR-<i>E</i>. <i>coli</i> detected with nitroblue tetrazolium (NBT) in an agarose gel. The top panels demonstrate a change in the <i>E</i>. <i>coli</i> with KillerRed before and after irradiation. A magnified portion (right) of the agarose gel near the KR-<i>E</i>. <i>coli</i> containing central pool indicates a formazan precipitation due to the diffusion of superoxide from the pool. Bar, 5 mm. The bottom panels demonstrate change in the color of the <i>E</i>. <i>coli</i> without KillerRed expression before and after irradiation.</p

Intratumoral proliferation of KR-<i>E</i>. <i>coli</i>.

<p><b>a,</b> NPC tumor subcutaneously formed in a nude mouse. <b>b,</b> The distribution of KR-<i>E</i>. <i>coli</i> immediately after intratumoral injection (left), and one day after the injection (right). Scale bar, 5 mm. <b>c,</b> Quantification of the fluorescence intensity of KR-<i>E</i>. <i>coli</i> immediately after the intratumoral injection and one day after the injection (n = 10). *p<0.001 (<i>t</i>-test). Error bars indicate standard error of the mean (SEM). The fluorescence intensity was calculated by summating the digital values of all points in the field of view, and expressed in a relative manner.</p

Absence of singlet oxygen in the phototoxic effect of illuminated KR-<i>E</i>. <i>coli</i>.

<p>To quantitatively measure the singlet oxygen produced by KillerRed, the intensity of spontaneous luminescence was measured at wavelengths in a near infrared region. (1) KillerRed in PBS. (2) KillerRed in an O₂-saturated solution. (3) KillerRed in a deuterium oxide (D₂O) solution. (4) Methylene blue solution used as a control. In reference to methylene blue, KillerRed did not produce any singlet oxygen upon irradiation.</p

Media 1: Dynamic autofluorescence imaging of intracellular components inside living cells using direct electron beam excitation

Originally published in Biomedical Optics Express on 01 February 2014 (boe-5-2-378

Media 1: Dynamic and high-resolution live cell imaging by direct electron beam excitation

Originally published in Optics Express on 27 February 2012 (oe-20-5-5629