Buckling of Carbon Honeycombs: A New Mechanism for Molecular Mass Transportation

<p>Differentially expressed genes in the CD34+ cell fraction in MDS patients versus controls.</p

Differentially expressed genes in the CD71+ cell fraction in MDS patients versus controls.

<p>Differentially expressed genes in the CD71+ cell fraction in MDS patients versus controls.</p

Expression of <i>BIK</i> in MDS patients and controls.

<p><i>BIK</i> expression in ‘low risk’ patients, ‘high risk’ patients and controls. The expression of <i>BIK</i> is depicted relative to the housekeeping gene <i>GAPDH</i>. Median level of expression is indicated.</p

Quenching of FITC fluorescent lyophilisomes by trypan blue in the absence of cells.

<p>Results show decreased fluorescence (a) and efficient quenching (b) up to three washings steps of FITC fluorescent lyophilisomes by trypan blue.</p

Schematic illustration of the conjugation of the cell-penetrating peptide (CPP) TAT to lyophilisomes.

<p>(1) Primary amine groups of lyophilisomes react with Sulfo-GMBS introducing reactive maleimide groups. (2) CPPs (cysteine-functionalized TAT-peptides; C-Ahx-YGRKKRRQRRR) are conjugated to maleimide-conjugated lyophilisomes, resulting in stable CPP-conjugated lyophilisomes. Sulfo-GMBS  =  sulfo-<i>N</i>-[γ-maleimidobutyryloxy]sulfo succinimide ester; Ahx  =  aminohexanoic acid; TAT  =  trans-activating transcriptional activator.</p

Sorting of lyophilisomes by fluorescence-activated cell sorting.

<p>a/b) A representative size distribution of the initial lyophilisome population (a) and sorted lyophilisomes (b) is depicted, showing smaller lyophilisomes after sorting. Note the difference in x and y axes. c) Initial lyophilisome population depicted in a FACS dot plot with forward (size)/FITC-positive lyophilisome (FL1 channel) scatter where gated FITC-positive lyophilisomes were sorted. d) After sorting, the scatter showed merely small lyophilisomes, as large lyophilisomes were removed.</p

Cellular binding and internalization of unmodified lyophilisomes and TAT-conjugated lyophilisomes.

<p>HeLa, OVCAR-3, Caco-2 and SKOV-3 cells incubated with TAT-conjugated and unmodified lyophilisomes resulted in 86±3% and 12±4%, 87±3% and 16±8%, 97±3% and 19±3%, and 95±10% and 67±20% lyophilisome-positive cells, respectively. TAT  =  trans-activating transcriptional activator. *p<0.01 ***p<0.0001.</p

Cellular uptake of TAT-conjugated lyophilisomes as analyzed by transmission electron microscopy.

<p>HeLa cells were incubated with unmodified (a) and TAT-conjugated lyophilisomes (b-d) for 4 h. a) No attachment or uptake was observed using unmodified lyophilisomes. b-d) TAT-conjugated lyophilisomes (white arrows) showed various processes required for effective drug delivery systems, such as attachment (b) and uptake (c). Additionally, signs of degradation of the capsule inside the cell were visualized (black arrows, d). Scale bar represents 1.0 µm. TAT  =  trans-activating transcriptional activator.</p

Internalization of lyophilisomes with and without TAT peptide into HeLa cells.

<p>FACS showed a large number of lyophilisome-positive cells for TAT-conjugated lyophilisomes after 1 h (67±3%) without trypan blue and a cellular uptake of 25±1% with trypan blue. Values for lyophilisomes without TAT peptide were low. When lyophilisomes were incubated for 4 h, TAT-conjugated lyophilisomes conserved the large number of lyophilisome-positive cells (79±8%) with an increased internalization of 59±14%, while unmodified lyophilisomes still showed few lyophilisome-positive cells and little cellular uptake. *p<0.01 **p<0.001. CPP  =  cell penetrating peptide; TAT  =  trans-activating transcriptional activator.</p