A naturally occurring nanomaterial from the Sundew (Drosera) for tissue engineering

In recent years advances have been made in the design of novel materials for tissue engineering through the use of polysaccharides. This study evaluated the ability of a naturally secreted polysaccharide adhesive from the Sundew (Drosera capensis) as a support for cell growth. The Sundew adhesive has several advantages including its high elasticity and antibiotic nature. By coating glass cover slips with the Sundew adhesive, a network of nanofibers was generated that was capable of promoting attachment and differentiation of a model neuronal cell line, PC-12. We also demonstrated the potential of this material for repairing bone and soft tissue injuries, by testing attachment of osteoblasts and endothelial cells. Finally, it was determined that the Sundew biomaterial was stable through testing by atomic force microscopy and prolonged cell growth. This work has proven the capabilities of using a nanomaterial derived from the Sundew adhesive for the purpose of tissue engineering.

Critical role of γ4 chain in the expression of functional Vγ4Vδ1 T cell receptor of gastric tumour-infiltrating γδT lymphocytes

Vγ4Vδ1 T cell receptor (TCRγ4δ1)-expressing γδT cells were the most dominant subset in gastric tumour-infiltrating γδT cells (γδTIL) we recently analyzed. To study the essential roles of γ and δ chains in assembly and function of TCRγ4δ1, we sequenced and constructed them into lentiviral vectors for the reconstitution of TCRγ4δ1 using different modalities of transduction. We were able to efficiently reconstitute TCRγ4δ1 with functional activities when both γ4 and δ1 chains are coexpressed in TCR-negative J.RT3-T3.5 cells. However, the expression of δ1 chain is greatly diminished when γ4 expression is absent, suggesting that the coexpressing γ4 is critical in maintaining the folding and stability of δ1 product. To functionally study the reconstituted TCRγ4δ1, we examined the cytolytic activity of TCRγ4δ1-reconstituted J.RT3-T3.5 cells and cytokine secretion and found the receptors are fully functional, but their functionality also requires the presence of γ4. Our results demonstrated that γ4 is critical for the stability of δ1 and the function of TCRγ4δ1.

Metastatic breast cancer detection and therapy monitoring using folate-targeting flow cytometry

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Background: Circulating tumor cell (CTC) has emerged as a valuable surrogate tumor marker for cancer diagnosis, prognosis, therapy personalization, and drug discovery. To identify CTCs, EpCAM and/or cytokeratin have been commonly used; however, their expression may diminish for subgroups of breast cancers or during epithelial-mesenchymal transition. A unique approach by targeting folate receptor (FR) on CTCs overcomes the limitation. Cancer cells overexpress FR with high affinity (KD=0.1 nM) to internalize high levels of folate for rapid growth. FR is also found upregulated in most cancers, while at very low levels in normal tissues.

Methods: A flow cytometry based in-vitro CTC assay kit (OncoIVDx) was developed by IV Diagnostics Inc to specifically enumerate CTCs which overexpress FRs. 20 mL of 9 metastatic breast cancer (MBC) patients' peripheral blood was collected using CellSave tube before and after the treatment in midst of therapy. CTCs were tagged by fluorescently labeled folate conjugate, while leukocytes were counterstained by anti-CD45. To absolutely count the rare CTCs, a fluorescent bead was added serving internal control.

Results: Table.

Conclusions: No obvious shift in dot plots was found for patients' leucocytes compared to those in normal sample. Tumor size, histologic grade, nodal involvement and lymphovascular invasion (LVI) did not display a significant association with CTC presence, although more positive nodes with identified LVI might indicate an unfavorable increase in CTC counts. CTC presence was found associated with serum marker CA27.29. A score of 30 and less correlated with CTC response to the treatment. Chemotherapy alone or in combination with hormone therapy did not correlate with the change in CTC counts after treatment, except for hormone therapy alone. Unfavorable progression of cancers could be predicated for the patients with approximately 25 and more CTCs. We would like to thank NIH/NCI for SBIR phase I grant (1R43CA13789301A1).

[Table: see text]

Macrophage LXRα gene therapy ameliorates atherosclerosis as well as hypertriglyceridemia in LDLR(-/-) mice

Liver X receptors (LXRs) are implicated in the regulation of cholesterol homeostasis, inflammatory response and atherogenesis. Administration of LXR agonists inhibits the progress of atherosclerosis, and also increases plasma triglyceride levels, representing an obstacle to their use in treating this disease. The objective of this study was to develop an alternative approach that could overcome this obstacle. Eight-week-old low-density lipoprotein receptor-deficient (LDLR(-/-)) mice were transplanted with hematopoietic stem cell (HSC)-enriched bone marrow cells transduced with lentivectors expressing either green fluorescent protein (GFP) (Lenti-SP-GFP, control) or LXRα (Lenti-SP-LXRα) driven by a synthetic macrophage promoter. At 4 weeks post-transplant, the mice were fed with a Western diet for 8 weeks and then killed. Compared with Lenti-SP-GFP mice, the Lenti-SP-LXRα mice had a 30% reduction in atherosclerotic lesions, which was accompanied by increases in levels of macrophage expression of cholesterol efflux genes apolipoprotein E and ATP-binding cassette A1, as well as decreases in plasma inflammatory cytokines interleukin-6 and tumor necrosis factor-α. Intriguingly, a 50% reduction of plasma triglyceride level was also observed. We conclude that HSC-based macrophage LXRα gene therapy ameliorates the development of atherosclerosis along with an unexpected concomitant reduction of plasma triglyceride levels in LDLR(-/-) mice. These findings highlight the potential value of macrophage LXR expression as an avenue for therapeutic intervention against atherosclerosis.

Expressions of BAFF/BAFF receptors and their correlation with disease activity in Chinese SLE patients

B-cell activating factor belonging to tumour necrosis factor family (BAFF) is essential for B-cell survival and function through interaction with its receptors BAFF receptor 3 (BR3), B-cell maturation antigen (BCMA) and/or transmembrane activator and calcium modulator and cyclophilin ligand interactor (TACI), though BCMA and/or TACI can also bind to a proliferation-inducing ligand (APRIL). We evaluate the correlation of the expressions of these ligands/receptors with different clinical manifestations of systemic lupus erythematosus (SLE). Levels of BAFF and APRIL in plasma from 73 SLE patients were determined by enzyme-linked immunosorbent assay. Expressions of BR3, TACI and BCMA on CD19+ B cells were detected by flow cytometry. Clinical data were collected and disease activity was evaluated using SLEDAI-2000. SLE patients had elevated BAFF and APRIL levels in their plasma. BAFF levels correlated positively with SLEDAI while negatively with the BR3 protein expression on CD19+ B cells (p < .05). The detected BR3 protein expression in SLE patients was reduced on CD19+IgD+CD27-, CD19+IgD+CD27+ as well as CD19+IgD-CD27+ B cells compared to the counterparts of healthy controls (p < .001), whereas SLE patients did not differ from healthy controls in BR3 mRNA levels. In untreated new-onset patients, the expression rate of BR3 on CD19+ B cells correlated negatively with SLEDAI (p < .05). Elevation of BAFF and reduction of BR3 on CD19+ B cells were more obvious in those with lupus nephritis (LN, p < .05). TACI expression on CD19+ B cells was up-regulated only in those subjects with LN (p < .05). Elevated plasma BAFF and reduced BR3 protein expression on peripheral B cells could act as biomarkers for active disease in SLE patients. High expression of TACI may indicate the occurrence of LN.

Transforming growth factor beta 1 plays an important role in inducing CD4(+)CD25(+)forhead box P3(+) regulatory T cells by mast cells

The role of mast cells (MCs) in the generation of adaptive immune responses especially in the transplant immune responses is far from being resolved. It is reported that mast cells are essential intermediaries in regulatory T cell (T(reg)) transplant tolerance, but the mechanism has not been clarified. To investigate whether bone marrow-derived mast cells (BMMCs) can induce T(regs) by expressing transforming growth factor beta 1 (TGF-β1) in vitro, bone marrow cells obtained from C57BL/6 (H-2(b) ) mice were cultured with interleukin (IL)-3 (10 ng/ml) and stem cell factor (SCF) (10 ng/ml) for 4 weeks. The purity of BMMCs was measured by flow cytometry. The BMMCs were then co-cultured with C57BL/6 T cells at ratios of 1:2, 1:1 and 2:1. Anti-CD3, anti-CD28 and IL-2 were administered into the co-culture system with (experiment groups) or without (control groups) TGF-β1 neutralizing antibody. The percentages of CD4(+)CD25(+)forkhead box P3 (FoxP3)(+) T(regs) in the co-cultured system were analysed by flow cytometry on day 5. The T(reg) percentages were significantly higher in all the experiment groups compared to the control groups. These changes were deduced by applying TGF-β1 neutralizing antibody into the co-culture system. Our results indicated that the CD4(+) T cells can be induced into CD4(+)CD25(+)FoxP3(+) T cells by BMMCs via TGF-β1.

The expression of frizzled-3 receptor in colorectal cancer and colorectal adenoma

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Background: Wnt signaling is well known for its role in colorectal cancer (CRC) formation through transcriptional activities of nuclear β-catenin. Although activation of Wnt signaling depends on specific Wnt/Frizzled receptors (FZD) combinations, the specificity of the interaction and the role of FZD in that particular interaction are still unknown. Among the 10 Wnt receptors of the FZD protein family, FZD-3 is involved in neurodevelopmental abnormalities and gastric cancer carcinogenesis. However, the expression of FZD-3 in CRC is not clear. Therefore in this study, we examined the expression of FZD-3 in CRC cell lines and CRC patient tissues with various pathological stages. The information obtained will be important for us to understand the role of FZD-3 in the development of CRC.

Methods: FZD-3 mRNA expression was studied in CRC metastatic SW620, primary SW480 and normal CCD18co cell lines using quantitative real-time polymerase chain reaction with primers and a Taqman minor grove binder probe (Applied Biosystems, Foster City, USA). Moreover, paraffin-embedded specimens of 40 CRC patient tissues, 25 colorectal adenoma (CA) tissues were retrieved from the Department of Pathology, Queen Elizabeth Hospital, Hong Kong Special Administrative Region for FZD-3 immunostaining using an anti-FZD-3 antibody (Catalog no: MAB1001, R&D systems Inc., Minneapolis, USA) in an automatic Ventana Benchmark XT immunostainer (Ventana Medical Systems Inc., Tucson, USA).

Results: FZD-3 mRNA was up-regulated in metastatic SW620 cell line (fold-change: 622) and in primary SW480 cell line (fold-change: 820) when compared to that in normal CCD18co cell line. Furthermore, immunostaining showed that FZD-3 protein was expressed in 100% (40/40) of CRC specimens and 84% (21/25) of CA specimens. Detailed analysis showed that FZD-3 protein was significantly up-regulated in CRC, CA when compared to their adjacent normal colorectal epithelial tissues (p < 0.0005, Wilcoxon matched pairs test).

Conclusions: This study provided evidence that FZD-3 is involved in CRC carcinogenesis and it is a potential therapeutic target in CRC.

No significant financial relationships to disclose.

Associations of fat mass and fat distribution with bone mineral density in pre- and postmenopausal Chinese women

Fat mass (FM) is closely related to bone mineral density (BMD). However, the associations of FM and fat distribution with BMD in pre- and postmenopausal women are still poorly understood. The present study showed android fat mass accumulation after menopause had a negative association with BMD.

INTRODUCTION

FM is closely related to BMD. However, it is unknown whether FM and central fat distribution have different associations with BMD in pre- and postmenopausal women. The study aims to investigate the associations of FM and fat distribution with BMD in pre- and postmenopausal Chinese women.

METHODS

Two hundred sixty premenopausal and 267 postmenopausal women aged 18 to 79 years were analyzed. Lean mass (LM), FM, percent body fat (%BF), android FM, gynoid FM, and total and regional BMD were measured using dual-energy X-ray absorptiometry. Fat distribution was assessed by android to gynoid FM ratio (AOI). Multiple regression analysis was performed to examine the associations of BMD with FM, LM, and AOI.

RESULTS

FM, %BF, android FM, and AOI were significantly higher, whereas total and regional BMD were significantly lower in postmenopausal women (all р < 0.01). In premenopausal women, FM was positively associated with total and regional BMD (all р < 0.05). AOI had no significant association with BMD. In postmenopausal women, FM was significantly associated with total and regional BMD even additionally adjusting for LM (all р < 0.01). AOI had significantly negative association with total, head, arm, and leg BMD (all р < 0.05). The results remained unchanged when replacing FM with %BF.

CONCLUSIONS

There were different associations of FM and fat distribution with BMD in pre- and postmenopausal Chinese women. Increased central body fat had a negative association with BMD. Our findings may have significant implications in the prevention of menopause-related osteoporosis through reducing centralized fat deposition.

Responses of bone-forming cells on pre-immersed Zr-based bulk metallic glasses: Effects of composition and roughness

Bulk metallic glasses (BMGs) demonstrate attractive properties for potential biomedical applications, owing to their amorphous structure. The present work has investigated the biocompatibility of Zr-based BMGs by studying the cellular behavior of bone-forming mouse MC3T3-E1 pre-osteoblast cells. A Ti-6Al-4V alloy was used as a reference material. Pre-immersion treatment was performed on BMG samples in phosphate-buffered saline prior to cell experiments. The effects of 1at.% yttrium alloying and surface roughness on cellular behavior were examined. The general biosafety of Zr-based BMGs for MC3T3-E1 cells was revealed as normal cell responses. Pre-immersion treatment was found to effectively reduce the surface concentrations of alloying elements. Micro-alloying with 1 at.% yttrium did not significantly affect cell adhesion and proliferation, but slightly decreased alkaline phosphatase (ALP) activity on rough surfaces. Lower cell adhesion and proliferation were found on smooth surfaces of Zr-based BMGs compared to their rougher counterparts. Higher ALP activity was detected on rougher surfaces. To obtain a mechanistic understanding surface free energy was correlated with cell adhesion.

A novel cylindrical TE(2,1) mode converter

A novel, compact arrangement for Ka-band mode couplers, which convert a rectangular waveguide TE(1,0) to cylindrical waveguide TE(2,1) mode, has been designed, constructed, and tested. The design features a set of longitudinal slots, positioned in regions of negligible current flow for the TE(2,1) mode, allowing its propagation to be preferentially favored, by suppression of the fundamental TE(1,1) mode. Numerical simulations and experimental measurements display good agreement, showing transmission of the intended TE(2,1) mode at levels of better than -5 dB, from a frequency of ∼37.5 to 41 GHz. Subsequent farfield measurements confirm the presence of the TE(2,1) mode, demonstrating good agreement when compared with analytical expectations. Such a device would be an ideal candidate for an application where mode purity, bandwidth, and ease of construction are of primary importance and where the transmission efficiency is of limited concern.

Anti-sports anaemia effects of verbascoside and martynoside in mice

This paper aims to investigate the effects of verbascoside and martynoside isolated from PEDICULARIS DOLICHOCYMBA on sports anaemia. Forty mice were divided into four groups: Group R (control group, nonsupplemented and maintained at rest), Group E (nonsupplemented and undergoing exercise), Group VE (supplemented with verbascoside 10 mg/kg per day and undergoing exercise), and Group ME (supplemented with martynoside 10 mg/kg per day and undergoing exercise). After 5 weeks intensive swimming exercises, we measured the RBC count, the hemoglobin concentration, the hematocrit (Hct), the mean corpuscular hemoglobin concentration (MCHC) and the mean corpuscular hemoglobin (MCH). We studied the shapes of RBC and measured the plasma malonyldialdehyde (MDA). We found Group E showed lower RBC, hemoglobin and Hct levels, higher MCHC, MCH, plasma MDA levels and the abnormally shaped RBCs percentage than Groups R, VE and ME. Group ME showed lower RBC and Hct levels, higher MCH, plasma MDA levels and the abnormally shaped RBCs percentage than Group VE. The results indicated that verbascoside and martynoside have the potential of antagonizing sports anaemia, the mechanism of this effect might be related to preventing RBC from free radical damage. Moreover, verbascoside was found to be more active than martynoside.