SFTA2 - a novel secretory peptide highly expressed in the lung - is modulated by lipopolysaccharide but not hyperoxia

Tissue-specific transcripts are likely to be of importance for the corresponding organ. While attempting to define the specific transcriptome of the human lung, we identified the transcript of a yet uncharacterized protein, SFTA2. In silico analyses, biochemical methods, fluorescence imaging and animal challenge experiments were employed to characterize SFTA2. Human SFTA2 is located on Chr. 6p21.33, a disease-susceptibility locus for diffuse panbronchiolitis. RT-PCR verified the abundance of SFTA2-specific transcripts in human and mouse lung. SFTA2 is synthesized as a hydrophilic precursor releasing a 59 amino acid mature peptide after cleavage of an N-terminal secretory signal. SFTA2 has no recognizable homology to other proteins while orthologues are present in all mammals. SFTA2 is a glycosylated protein and specifically expressed in nonciliated bronchiolar epithelium and type II pneumocytes. In accordance with other hydrophilic surfactant proteins, SFTA2 did not colocalize with lamellar bodies but colocalized with golgin97 and clathrin-labelled vesicles, suggesting a classical secretory pathway for its expression and secretion. In the mouse lung, Sfta2 was significantly downregulated after induction of an inflammatory reaction by intratracheal lipopolysaccharides paralleling surfactant proteins B and C but not D. Hyperoxia, however, did not alter SFTA2 mRNA levels. We have characterized SFTA2 and present it as a novel unique secretory peptide highly expressed in the lung

Detection of Landmine Signature using SAW-based Polymer-coated Chemical Sensor

The explosive charge within a landmine is the source for a mixture of chemical vapours that form a distinctive chemical signature indicative of a landmine. The concentrations of these compounds in the air over landmines is extremely low (parts-per-trillion or lower), well below the minimum detection limits of most field-portable chemical sensors. This paper describes a portable  surface acoustic wave-based polymer-coated sensor for the detection of hidden explosives. The sensitivity and selectivity of polymer-based sensors depend on several factors including the chemo-selective coating used, the physical properties of the vapour(s) of interest, the selected transducers, and the operating conditions. The polymer-based sensor was calibrated in the  laboratory using the explosive vapour generator. The preliminary results indicated that the carbowax 1000 could be a very good chemical interface to sense low levels of chemical signature of explosive material. Response for 50 ppb of TNT vapours was observed to be 400 Hz for an exposure of 2 min

Characterization of Ku702–NLS as Bipartite Nuclear Localization Sequence for Non-Viral Gene Delivery

Several barriers have to be overcome in order to achieve gene expression in target cells, e.g. cellular uptake, endosomal release and translocation to the nucleus. Nuclear localization sequences (NLS) enhance gene delivery by increasing the uptake of plasmid DNA (pDNA) to the nucleus. So far, only monopartite NLS were analysed for non-viral gene delivery. In this study, we examined the characteristics of a novel bipartite NLS like construct, namely NLS Ku70. We synthesized a dimeric structure of a modified NLS from the Ku70 protein (Ku702-NLS), a nuclear transport active mutant of Ku702-NLS (s1Ku702-NLS) and a nuclear transport deficient mutant of Ku702-NLS (s2Ku702). We examined the transfection efficiency of binary Ku702-NLS/DNA and ternary Ku702-NLS/PEI/DNA gene vector complexes in vitro by using standard transfection protocols as well as the magnetofection method. The application of Ku702-NLS and s1Ku702-NLS increased gene transfer efficiency in vitro and in vivo. This study shows for the first time that the use of bipartite NLS compounds alone or in combination with cationic polymers is a promising strategy to enhance the efficiency of non-viral gene transfer

ADENOSINE MODULATION OF CELL GROWTH IN BABY HAMSTER KIDNEY CELLS

Master'sMASTER OF SCIENC

Bioactive compounds and their libraries: An insight into prospective phytotherapeutics approach for oral mucocutaneous cancers

Oral mucocutaneous cancers (OMCs) are cancers that affect both the oral mucosa and perioral cutaneous structures. Common OMCs are squamous cell carcinoma (SCC), basal cell carcinoma (BCC) and malignant melanoma (MM). Anatomical similarities and conventions which categorizes these lesions blur the magnitude of OMCs in diverse populations. The burden of OMC is high in the sub-Saharan Africa and Indian subcontinents, and the cost of management is prohibitive in the resource-limited, developing world. Hence, there is a pressing demand for the use of cost-effective in silico approaches to identify diagnostic tools and treatment targets for diseases with high burdens in these regions. Due to their ubiquitousness and accessibility, the use of therapeutic efficacy of plant bioactive compounds in the management of OMC is both appropriate and plausible. Furthermore, screening known mechanistic disease targets with well annotated plant bioactive compound libraries is poised to improve the routine management of OMCs provided that the requisite access to database resources are available and accessible. Using natural products minimizes the side effects and morbidities associated with conventional therapies. The development of innovative treatments approaches would tremendously benefit the African and Indian populace and reduce the mortalities associated with OMCs in the developing world. Hence, we discuss herein, the potential benefits, opportunities and challenges of using bioactive compound libraries in the management of OMCs

Relative <i>SFTA2</i> mRNA levels in human tissues normalized to GAPDH.

<p>Out of 48 tissues investigated, those with mRNA levels above 0.1% of lung are listed. The relative amount of the lung was set to 100. The lung is the predominant site of expression, while there is expression >1% of lung also in cervix, esophagus, stomach, testis, kidney and rectum. Normalization for β-actin resulted in the same pattern.</p

Immunofluorescence microscopic analysis of A549 cells transfected with an HA epitope-tagged SFTA2 expression plasmid. A.

<p>Partial colocalization with golgin97 indicates passage of SFTA2 through the Golgi apparatus. <b>B.</b> Partial colocalization with clathrin indicates presence of SFTA2 in secretory vesicles consistent with the classical pathway of secretion.</p

Alignment of SFTA2 amino acid sequences from 21 mammalian species.

<p>Secretory and glycosylation signals are recognized in all species. Shaded amino acid residues indicate a conservation of >70% (black: identical; grey: conserved). All species missing N-glycosylation signal 1 (position 37; pig, pika, mouse rat) have a signal at position 61. While only five amino acid residues are identical in all species (black dots), the only two cysteine residues are among them (red dots).</p

Frozen section immunofluorescence microscopic analysis of SFTA2 in the human lung.

<p>While DAPI stains all nuclei, TTF-1 (thyroid transcription factor-1) antibodies label nuclei of type II pneumocytes and nonciliated bronchiolar epithelial cells only. <b>A.</b> The SFTA2 polyclonal peptide antibody demonstrates cytoplasmic staining localizing to the same cells as TTF-1 in alveoli (indicating SFTA2 expression restricted to type II pneumocytes in the alveolus). <b>B.</b> SFTA2 signals also colocalize with TTF-1 in nonciliated bronchiolar epithelium. Merge: superimposition of all exposures including differential interference contrast to visualize tissue morphology.</p

Immunofluorescence microscopic analyses in A549 (A, B) and MLE12 (C) cells after transfection with pCDNA-SFTA2-HA

<p>. <b>A.</b> Cells were analyzed with an HA epitope antibody and an SFTA2-specific peptide antibody. Colocalization of HA and SFTA2 signals indicates that our SFTA2 antibody recognizes human SFTA2 resulting from transfection. The punctate cytoplasmic pattern is consistent with localization in secretory vesicles. The background signal of non-transfected cells may have resulted from natural SFTA2 expression in A549 cells. <b>B.</b> SFTA2-HA signals do not colocalize with lysosomes or lysosome-related organelles such as lamellar bodies as indicated by LAMP1 immunostaining. <b>C.</b> In MLE12 cells, transfection with a plasmid construct encoding the phospholipid transporter ABCA3 labels the outer membrane of lamellar bodies as ring-like structures while epitope-tagged SFTA2 yields a distinctly different punctate cytoplasmic pattern.</p