Changes in the Expression of Transcription Factors Involved in Modulating the Expression of EPO-R in Activated Human CD4-Positive Lymphocytes.

We have recently described the presence of the erythropoietin receptor (EPO-R) on CD4(+) lymphocytes and demonstrated that its expression increases during their activation, reaching a level reported to be typical for erythroid progenitors. This observation suggests that EPO-R expression is modulated during lymphocyte activation, which may be important for the cells' function. Here we investigated whether the expression of GATA1, GATA3 and Sp1 transcription factors is correlated with the expression of EPO-R in human CD4(+) lymphocytes stimulated with monoclonal anti-CD3 antibody. The expression of GATA1, GATA3 and Sp1 transcription factors in CD4(+) cells was estimated before and after stimulation with anti-CD3 antibody by Western Blot and flow cytometry. The expression of EPO-R was measured using real-time PCR and flow cytometry. There was no change in the expression of GATA1 and GATA3 in CD4(+) lymphocytes after stimulation with anti-CD3 antibody. However, stimulation resulted in the significantly increased expression of the Sp1 factor. CD4(+) lymphocytes stimulated with anti-CD3 antibody exhibited an increase in both the expression level of EPOR gene and the number of EPO-R molecules on the cells' surface, the latter being significantly correlated with the increased expression of Sp1. Sp1 is noted to be the single transcription factor among the ones studied whose level changes as a result of CD4(+) lymphocyte stimulation. It seems that Sp1 may significantly affect the number of EPO-R molecules present on the surface of activated CD4(+) lymphocytes

Comparison of GATA1, GATA3 and Sp1 expression determined by Western Blot in isolated CD4⁺ lymphocytes before and after stimulation with anti-CD3 antibody.

<p>Figure A shows representative results. Figure B presents mean expression of GATA1, GATA3 and Sp1 in arbitrary densitometric units. Figures C, D and E present expression of GATA1, GATA3 and Sp1, respectively. Midpoints of figures present medians, boxes present the 25 and 75 percentile and whiskers outside visualize the minimum and maximum of all the data, *p<0.05, Friedman ANOVA and Post Hoc test.</p

Fluorescence analysis of EPO-R and Sp1 expression measured by flow cytometry in CD4⁺ lymphocytes before and after stimulation with anti-CD3 antibody.

<p>CD4⁺ cells were selected on the basis of forward and side scatter characteristics of lymphocytes, <i>Gate 1</i> (A, E) and expression of CD4 antigen in gated lymphocytes, <i>Gate 2</i> (B, F). Figures C and D present the expression of EPO-R and Sp1 in CD4⁺ cells (cells from <i>Gate 1</i> and <i>Gate 2</i>) before stimulation, figures G and H present the expression of EPO-R and Sp1 in CD4⁺ cells stimulated with anti-CD3 antibody for 48 hours, respectively. For individual samples, expression of EPO-R and Sp1 was estimated as mean fluorescence shift (black line) toward isotype control (gray histogram): δMFI = MFI of the population of interest – MFI of the appropriate isotype control. Quantitative fluorescence analysis assessing the number of EPO-R molecules per cell based on δMFI was performed as previously described <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0060326#pone.0060326-Lisowska1" target="_blank">[3]</a>.</p

Changes in the number of EPO-R molecules per cell, <i>EPOR</i> gene expression and Sp1 expression in CD4⁺ lymphocytes before and after stimulation with anti-CD3 antibody.

<p>The figure shows results from 3 different individuals, MFI – mean fluorescence intensity, RFU – relative fluorescence units.</p

Acid&ndash;Base Equilibrium and Self-Association in Relation to High Antitumor Activity of Selected Unsymmetrical Bisacridines Established by Extensive Chemometric Analysis

Unsymmetrical bisacridines (UAs) represent a novel class of anticancer agents previously synthesized by our group. Our recent studies have demonstrated their high antitumor potential against multiple cancer cell lines and human tumor xenografts in nude mice. At the cellular level, these compounds affected 3D cancer spheroid growth and their cellular uptake was selectively modulated by quantum dots. UAs were shown to undergo metabolic transformations in vitro and in tumor cells. However, the physicochemical properties of UAs, which could possibly affect their interactions with molecular targets, remain unknown. Therefore, we selected four highly active UAs for the assessment of physicochemical parameters under various pH conditions. We determined the compounds&rsquo; pKa dissociation constants as well as their potential to self-associate. Both parameters were determined by detailed and complex chemometric analysis of UV-Vis spectra supported by nuclear magnetic resonance (NMR) spectroscopy. The obtained results indicate that general molecular properties of UAs in aqueous media, including their protonation state, self-association ratio, and solubility, are strongly pH-dependent, particularly in the physiological pH range of 6 to 8. In conclusion, we describe the detailed physicochemical characteristics of UAs, which might contribute to their selectivity towards tumour cells as opposed to their effect on normal cells

Universality of the triangular theory of love: Adaptation and psychometric properties of the triangular love scale in 25 countries

The Triangular Theory of Love (measured with Sternberg\u27s Triangular Love Scale - STLS) is a prominent theoretical concept in empirical research on love. To expand the culturally homogeneous body of previous psychometric research regarding the STLS, we conducted a large-scale cross-cultural study with the use of this scale. In total, we examined more than 11,000 respondents, but as a result of applied exclusion criteria, the final analyses were based on a sample of 7332 participants from 25 countries (from all inhabited continents). We tested configural invariance, metric invariance, and scalar invariance, all of which confirmed the cultural universality of the theoretical construct of love analyzed in our study. We also observed that levels of love components differ depending on relationship duration, following the dynamics suggested in the Triangular Theory of Love. Supplementary files with all our data, including results on love intensity across different countries along with STLS versions adapted in a few dozen languages, will further enable more extensive research on the Triangular Theory of Love