Project description:Human saliva has been commonly used as protein source in in vitro microbiological and biological assays to mimic the protein pellicle formation, termed acquired salivary pellicle, that precedes microbial and cell adhesion on surfaces exposed to the oral environment. However, saliva requires previous processing to remove food debris, microorganisms, and other molecules prior its use in microbiological and biological in vitro assays. For this purpose, 0.22 μm filtration, 0.45 μm filtration, and pasteurization methods have been commonly used, but the effect of these processing methods on the proteomic profile of saliva has not been tested experimentally. Stimulated human saliva was collected from 8 healthy volunteers and submitted to the following processes: non-processing (control), 0.22 μm filtration, 0.45 μm filtration, and pasteurization. The proteomic profile of non-processed saliva was compared with 0.22 μm filtered-, 0.45 μm filtered-, and pasteurized-saliva by liquid chromatography-mass spectrometry. The effect of processed saliva in microbial adhesion was tested using bacterial and fungus species, and in biological cell behavior using HaCaT immortalized human keratinocytes. Two hundred seventy-eight proteins were identified in non-processed saliva, 54 proteins (≈19%) were exclusive. Saliva processing reduced identified proteins to 222 (≈80%) for the 0.22 μm filtered saliva, 219 (≈79%) for the 0.45 μm filtered saliva, and 201 (≈72%) for the pasteurized saliva, compared to non-processed saliva. Although there were slight differences in the protein composition, the proteomic profile showed similar molecular functions and biological processes. The different saliva processing methods did not alter microbial adhesion (ANOVA, p>0.05). Interestingly, pasteurized saliva reduced keratinocytes cell viability. Saliva processing methods tested reduced the proteomic profile diversity of saliva, but maintained similar molecular functions and biological processes mediated by remaining proteins, not interfering on microbial adhesion and cell viability, except for pasteurization, which reduced cell viability.
Project description:Peripheral Blood gene expression is widely used in the discovery of biomarkers and development of therapeutics. Recently, a spate of commercial blood collection and preservation systems have been introduced with proprietary variations that may differentially impact the transcriptomic profiles. Comparative analysis of these collection platforms will help optimize protocols to detect, identify, and reproducibly validate true biological variance among subjects. In the current study, we tested two recently introduced whole blood collection methods, RNAgard® and PAXgene™ RNA, in addition to the traditional method of peripheral blood mononuclear cells (PBMCs) separated from whole blood and preserved in Trizol reagent. Study results revealed striking differences in the transcriptomic profiles from the three different methods that imply ex vivo changes in gene expression occurred during the blood collection, preservation, and mRNA extraction processes. When comparing the ability of the three preservation methods to accurately capture individuals’ expression differences, RNAgard® outperformed PAXgene™ RNA, and both showed significantly better individual separation of transcriptomic profiles than PBMCs. Hence, our study recommends using a single blood collection platform, and strongly cautions against combining methods during the course of a defined study.
Project description:RNA-Seq technique was applied to investigate the effects of two semen collection methods (Pelleted vs Liquefied) and two sperm purification methods (SCLB vs PS) to the integrity of isolated RNAs at different perspectives. The same set of semen samples were applied to investigate the qualitative and quantitative effect of semen collection methods and sperm cell purification methods on sperm transcript profiling.
Project description:RNA-Seq technique was applied to investigate the effects of two semen collection methods (Pelleted vs Liquefied) and two sperm purification methods (SCLB vs PS) to the integrity of isolated RNAs at different perspectives.
Project description:Saliva based diagnostics is a rapidly evolving field due to the large potential of saliva and the simple sample collection. A systematic comparison of IgG antibody profiles in saliva and plasma is currently lacking in scientific literature. Our hypothesis is that IgG profiles are equal in blood and saliva. By showing the equality of the profiles and relative IgG antigenic reactivities towards proteins and peptides we provide evidence that plasma IgG reactivities can be inferred from saliva IgG reactivities. IgG antibodies were isolated from human saliva and plasma samples. The reactivities of IgG isolates were analysed on peptide microarrays displaying linear epitopes of EBV (EBNA1 protein) and HBV (Large envelope protein) virus. Peptide arrays were printed by JPT Peptide Technologies (Berlin, Germany). We show high similarity of saliva and plasma IgG profiles on these two platforms and argue for generalisation from this subset to the whole immunological IgG antibody profile.
Project description:Saliva based diagnostics is a rapidly evolving field due to the large potential of saliva and the simple sample collection. A systematic comparison of IgG antibody profiles in saliva and plasma is currently lacking in scientific literature. Our hypothesis is that IgG profiles are equal in blood and saliva. By showing the equality of the profiles and relative IgG antigenic reactivities towards proteins and peptides we provide evidence that plasma IgG reactivities can be inferred from saliva IgG reactivities. IgG antibodies were isolated from human saliva and plasma samples. The reactivities of IgG isolates were analysed on peptide microarrays displaying linear epitopes of EBV (EBNA1 protein) and HBV (Large envelope protein) virus. Peptide arrays were printed by JPT Peptide Technologies (Berlin, Germany). We show high similarity of saliva and plasma IgG profiles on these two platforms and argue for generalisation from this subset to the whole immunological IgG antibody profile.
Project description:Saliva is a convenient non-invasive source of liquid biopsy to monitor human health and diagnose diseases. In particular, extracellular vesicles (EVs) in saliva can potentially reveal clinically relevant information for systemic health. Recent studies have shown that RNA in saliva EVs could be exploited as biomarkers for disease diagnosis. However, there is no standardized protocol for profiling RNA in saliva EV nor clear guideline on selecting saliva fractions for biomarker analysis. To address these issues, we established a robust protocol for small RNA profiling from fractionated saliva. With this method, we performed comprehensive small RNA sequencing of four saliva fractions, including cell-free saliva (CFS), EV-depleted saliva (EV-D), exosome (EXO), and microvesicle (MV) from ten healthy volunteers. Methods: To address these issues, we established a robust protocol for small RNA profiling from fractionated saliva. With this method, we performed comprehensive small RNA sequencing of four saliva fractions, including cell-free saliva (CFS), EV-depleted saliva (EV-D), exosome (EXO), and microvesicle (MV) from ten healthy volunteers.
Project description:Blood was collected from three healthy volunteers in 3 blood collection tubes: serum separator tube SST (serum), EDTA (plasma), and P100 (plasma) and stored at 4 degrees for 0, 0.5, 1, 2, 4, and 24 hours prior to centrifugation. Compounds were extracted using liquid-liquid extraction to obtain a hydrophilic and a hydrophobic fraction and analyzed using liquid chromatography mass spectrometry. Differences among the blood collection tubes and sample processing time were evaluated (ANOVA with Bonferroni FWER ≤ 0.05 and ANOVA with Benjamini Hochberg FDR ≤ 0.1, respectively).