Laser Desorption Postionization Mass Spectrometry Imaging of Folic Acid Molecules in Tumor Tissue

Mass spectrometry imaging (MSI) is an innovative and powerful tool in biomedical research. It is well-known that folic acid (FA) has a high affinity for folic acid receptor (FR), which is overexpressing in epithelial cancer. Herein, we propose a novel method to diagnose cancer through direct mapping of the label-free FA spatial distribution in tissue sections by state-of-the-art laser desorption postionization-mass spectrometry imaging (LDPI-MSI). Compared with other tumor imaging methods, such as fluorescence imaging, photoacoustic imaging (PAI), magnetic resonance imaging (MRI), and micro-SPECT/CT, complicated synthesis and labeling processes are not required. The LDPI-MSI was performed on 30 μm thick sections from a murine model of breast cancer (inoculation of 4T1 cells) that were predosed with 20 mg/kg of FA. The image obtained from the characteristic mass spectrometric signature of FA at <i>m</i>/<i>z</i> 265 illustrated that FA was concentrated primarily in tumor tissue and displayed somewhat lower retention in adjacent normal controls. The results suggest that the proposed method could be used potentially in cancer diagnosis

Observation of periodic optical spectra and soliton molecules in a novel passively mode-locked fiber laser

Due to the necessity of making a series of fine adjustments after mode-locking in most experiments for preparing soliton molecules, the repeatability of the preparations remains a challenge. Here, we propose a novel all-polarization-maintaining erbium-doped fiber laser that utilizes a nonlinear amplifying loop mirror for mode-locking and features a linear structure. This laser can stably output soliton molecules without any additional adjustment once the mode-locking self-starts. It can achieve all-optical switching to single-pulse operation through changing the pumping power, making it suitable for studying the mechanism of soliton molecule bond rupture. In addition, multi-pulse operation can also be achieved. Compared to the single-pulse state, this laser is operated in the multi-pulse state at a lower pumping power level, in contrast to previous methods that relied on increasing pumping power to generate multi-pulses. As a result, these multi-pulses are not susceptible to spectral distortion caused by nonlinear effects and maintain pulse stability close to that of the single-pulse. Furthermore, as the pumping power decreases, a peak with periodic intensity variation appears in the spectral center of both the single-pulse state and multi-pulse states. Combined with the experimental facts, we propose a multistability model to explain this phenomenon. With its ability to switch between soliton molecule, soliton, and multi-pulse states, this flexible laser can serve as a versatile toolbox for studying soliton dynamics

Phenotypes of hiPSCs and somatic cells (HSFs).

<p>White histograms represent the surface expression of MHC-I, MHC-II, HLA-G, HLA-E, CD40, CD80, and CD86, and gray histograms represent isotype controls. Data shown here are representative of three different experiments.</p

Characterization of hiPSCs.

<p>(A) Expression of human ES cell-specific cell surface markers on hiPSCs were analyzed by flow cytometry. Gray histograms: isotype controls; White histograms: positive staining of antigens. (B) Various tissues of all three germ layers present in teratomas derived from hiPSCs. Hematoxylin and eosin staining of teratoma sections. Scale bars, 500 µm.</p

Phenotypes of hiPSCs and somatic cells (HSFs).

<p>White histograms represent the surface expression of MHC-I, MHC-II, HLA-G, HLA-E, CD40, CD80, and CD86, and gray histograms represent isotype controls. Data shown here are representative of three different experiments.</p

hiPSCs induced the generation of IL-2- and IL-10-secreting T cells in MRL.

<p>Allogeneic PBMCs (responder cells; R) were co-cultured with hiPSCs (stimulator cells; S) at an R/S ratio of 10∶1 for 24 hours. The intracellular expressions of IL-2 and IL-10 in CD3⁺CD4⁺ and CD3⁺CD8⁺ T cells were examined by flow cytometry (A, B) (n = 7). Data shown as the mean ± SEM are representative of seven separate experiments. * <i>P<</i>0.05; ** P<0.01; *** P<0.001.</p

hiPSCs do not effectively induce activation and proliferation responses on allogeneic lymphocytes.

<p>hiPSCs pretreated with or without IFN-γ (stimulator cells; S) were inactivated and then directly cultured with allogeneic PBMCs (responder cells; R) at different R/S cell ratios in a MLR for 5–7 days (n = 4). PBMCs were harvested for examination of the expression of activation markers and Ki67 protein at the indicated time point. Surface expression of CD69 and CD25 on PBMCs, CD3⁺CD8⁺ T cells, and CD3⁺CD4⁺ T cells was measured by flow cytometry after 6 h and 24 h of co-culture (A, B). (C) Intranuclear Ki67 protein expression in PBMCs, CD3⁺CD8⁺ T cells and CD3⁺CD4⁺ T cells was analyzed after 5–7 d of stimulation. Data are shown as the mean ± SEM. Results are representative of four different experiments. #, indicating significant difference compared to those with different ratio of stimulator within same group (p<0.05). *, indicating significant difference compared to those with same and same ratio of stimulator (p<0.05).</p

Cytokine expression profile in MLR.

<p>Culture supernatants were collected from the MLR after 24 hours of culture and examined for expression of cytokines secreted by Th1 (A), Th2 (B), and Th17 (C) (n = 7). Data shown are single values for each point in the scatter plot. * <i>P<</i>0.05; ** P<0.01; *** P<0.001. The grey lines indicate the sensitivity of each cytokine.</p

Effect of IFN-γ on hiPSCs.

<p>(A) Expression of MHC proteins and costimulatory molecules by hiPSCs treated with 100 ng/ml of IFN-γ for 48h. Gray: isotype controls; Black: positive staining of antigens expressed on hiPSCs without IFN-γ treatment; White: positive staining of antigens expressed on hiPSCs treated with IFN-γ. (B) Concentration dependence of MHC-I induction by IFN-γ in hiPSCs. (C) Time response of MHC-I expression in hiPSCs treated with IFN-γ. (D) MHC-I expression gradually decreased after IFN-γ was withdrawn from the culture medium. Three independent experiments were performed for each analysis.</p

Gene Profile of Chemokines on Hepatic Stellate Cells of Schistosome-Infected Mice and Antifibrotic Roles of CXCL9/10 on Liver Non-Parenchymal Cells

<div><p>Hepatic stellate cells (HSCs) play a key role in the development of liver fibrosis caused by schistosomiasis. Chemokines were widely expressed and involved in cellular activation, proliferation and migration in inflammatory and infectious diseases. However, little is known about the expressions of chemokines on HSCs in the schistosoma infection. In addition, the roles of chemokines in pathogenesis of liver fibrosis are not totally clear. In our study, we used microarray to analyze the temporal gene expressions of primary HSCs isolated from mice with both acute and chronic schistosomiasis. Our microarray data showed that most of the chemokines expressed on HSCs were upregulated at 3 weeks post-infection (<em>p.i</em>) when the egg granulomatous response was not obviously evoked in the liver. However, some of them like CXCL9, CXCL10 and CXCL11 were subsequently decreased at 6 weeks <em>p.i</em> when the granulomatous response reached the peak. In the chronic stage, most of the differentially expressed chemokines maintained persistent high-abundances. Furthermore, several chemokines including CCR2, CCR5, CCR7, CXCR3, CXCR4, CCL2, CCL5, CCL21, CXCL9 and CXCL10 were expressed by HCSs and the abundances of them were changed following the praziquantel treatment in the chronic stage, indicating that chemokines were possibly necessary for the persistence of the chronic stage. In vitro experiments, hepatic non-parenchymal cells, primary HSCs and human HSCs line LX-2 were stimulated by chemokines. The results showed that CXCL9 and CXCL10, but not CXCL11 or CXCL4, significantly inhibited the gene expressions of Col1α1, Col3α1 and α-SMA, indicating the potential anti-fibrosis effect of CXCL9 and CXCL10 in schistosomiasis. More interestingly, soluble egg antigen (SEA) of <em>Schistosoma japonicum</em> was able to inhibit transcriptional expressions of some chemokines by LX-2 cells, suggesting that SEA was capable of regulating the expression pattern of chemokine family and modulating the hepatic immune microenvironment in schistosomiasis.</p> </div