Using the method of shotgun mass spectrometry, we have evaluated changes in the proteomic profile of HaCat cells in response to the treatment with sodium dodecyl sulfate (anionic surfactant) and Triton-X100 (non-ionic surfactant) in two concentrations (12.5 µg/ml and 25.0 µg/ml). The study revealed induction of orphan CYP2S1 (biotransformation phase I) in response to Triton-X100. We have identified proteins of II (glutathione-S-transferases, GSTs) and III (solute carrier proteins, SLCs) biotransformation phases, as well as antioxidant proteins (peroxiredoxins, PRDXs; catalase, CAT; thioredoxin, TXN). Thus, proteins of all three xenobiotic detoxification phases were detected. The presented results suggest a new prospect of using HaCaT keratinocytes as a model of human epidermis for studying the metabolism of drugs/toxicants in human skin in vitro.

Using tandem mass spectrometry with electrospray ionization, a comparative analysis of HaCaT keratinocyte proteins was carried out before and after exposure of cells to sodium dodecyl sulfate (25 mg/ml) for 48 hours; proteins encoded by human chromosome 18 genes were chosen as the comparison proteins. A total of 2418 proteins were detected in the HaCaT immortalized human keratinocytes, 70% of these proteins were identified by two or more unique peptides. Panoramic mass spectrometry analysis identified 38 proteins encoded by chromosome 18 genes, 27 proteins were common to control HaCaT cells and HaCaT cells exposed to SDS. Using the Metascape database (https://metascape.org), an enrichment analysis of GO terms of the Biological Process category of chromosome 18 gene encoded proteins of HaCaT keratinocytes was performed before and after the SDS exposure. The SDS exposure resulted in a slight enrichment of the GO term "response to stimulus" (GO:0050896) and the related GO term "negative regulation of biological process" (GO:0048519). We found decreased expression levels of membrane proteins encoded by chromosome 18 genes related to cell-cell adhesion (GO:0098609), such as DSC1, DSC3, and DSG1. A decrease in the expression level of desmosomal cadherins is characteristic of malignant neoplasms developing from epithelial tissue cells of various internal organs, mucous membranes, and skin. The method of preparation of HaCaT keratinocyte samples used in this work increased the sensitivity of proteomic analysis of cell culture and made it possible to identify twice as many proteins in one gel strip as compared to the number of proteins (1284) in HaCaT samples subjected to osmotic shock and cleavage by trypsin in solution.

Problems with the male reproductive system are of both medical and social significance. As a rule, spermatozoa and seminal plasma proteomes are investigated separately to assess sperm quality. The current study aimed to compare ejaculate proteomes with spermatozoa and seminal plasma protein profiles regarding the identification of proteins related to fertility scores. A total of 1779, 715, and 2163 proteins were identified in the ejaculate, seminal plasma, and spermatozoa, respectively. Among these datasets, 472 proteins were shared. GO enrichment analysis of the common proteins enabled us to distinguish biological processes such as single fertilization (GO:0007338), spermatid development (GO:0007286), and cell motility (GO:0048870). Among the abundant terms for GO cellular components, zona pellucida receptor complex, sperm fibrous sheath, and outer dense fiber were revealed. Overall, we identified 139 testis-specific proteins. For these proteins, PPI networks that are common in ejaculate, spermatozoa, and seminal plasma were related to the following GO biological processes: cilium movement (GO:0003341), microtubule-based movement (GO:0007018), and sperm motility (GO:0097722). For ejaculate and spermatozoa, they shared 15 common testis-specific proteins with spermatogenesis (GO:0007283) and male gamete generation (GO:0048232). Therefore, we speculated that ejaculate-based proteomics could yield new insights into the peculiar reproductive physiology and spermatozoa function of men and potentially serve as an explanation for male infertility screening.

An important step in the proteomic analysis of missing proteins is the use of a wide range of tissues, optimal extraction, and the processing of protein material in order to ensure the highest sensitivity in downstream protein detection. This work describes a purification protocol for identifying low-abundance proteins in human chorionic villi using the proposed “1DE-gel concentration” method. This involves the removal of SDS in a short electrophoresis run in a stacking gel without protein separation. Following the in-gel digestion of the obtained holistic single protein band, we used the peptide mixture for further LC–MS/MS analysis. Statistically significant results were derived from six datasets, containing three treatments, each from two tissue sources (elective or missed abortions). The 1DE-gel concentration increased the coverage of the chorionic villus proteome. Our approach allowed the identification of 15 low-abundance proteins, of which some had not been previously detected via the mass spectrometry of trophoblasts. In the post hoc data analysis, we found a dubious or uncertain protein (PSG7) encoded on human chromosome 19 according to neXtProt. A proteomic sample preparation workflow with the 1DE-gel concentration can be used as a prospective tool for uncovering the low-abundance part of the human proteome.

There is no direct evidence supporting that SDS is a carcinogen, so to investigate this fact, we used HaCaT keratinocytes as a model of human epidermal cells. To reveal the candidate proteins and/or pathways characterizing the SDS impact on HaCaT, we proposed comparative proteoinformatics pipeline. For protein extraction, the performance of two sample preparation protocols was assessed: 0.2% SDS-based solubilization combined with the 1DE-gel concentration (Protocol 1) and osmotic shock (Protocol 2). As a result, in SDS-exposed HaCaT cells, Protocol 1 revealed 54 differentially expressed proteins (DEPs) involved in the disease of cellular proliferation (DOID:14566), whereas Protocol 2 found 45 DEPs of the same disease ID. The 'skin cancer' term was a single significant COSMIC term for Protocol 1 DEPs, including those involved in double-strand break repair pathway (BIR, GO:0000727). Considerable upregulation of BIR-associated proteins MCM3, MCM6, and MCM7 was detected. The eightfold increase in MCM6 level was verified by reverse transcription qPCR. Thus, Protocol 1 demonstrated high effectiveness in terms of the total number and sensitivity of MS identifications in HaCaT cell line proteomic analysis. The utility of Protocol 1 was confirmed by the revealed upregulation of cancer-associated MCM6 in HaCaT keratinocytes induced by non-toxic concentration of SDS. Data are available via ProteomeXchange with identifier PXD035202.

Using electrospray ionization tandem mass spectrometry, a comparative analysis of the HaCaT keratinocyte proteins encoded by the 18th chromosome was performed before and after exposure to sodium dodecyl sulfate (25 mg/ml) and to Triton X-100 (12.5 mg/ml) in a subtoxic dose for 48 hours. Proteins were identified using the SearchGUI platform (X!Tandem and MS-GF+ search engines). In total, 1284 proteins were found in immortalized human HaCaT keratinocytes and about 75% of them were identified by two or more peptides. Were identified, that 26 proteins were encoded by genes of chromosome 18. Among these proteins, 17 were common for control cells and HaCaT cells treated with SDS. Proteins MARE2 and CTIF were identified only in control keratinocytes. Seven identified proteins encoded by genes of chromosome 18 were found only in detergent-treated keratinocytes: LMAN1, NDUV2, SPB3, VPS4B, KDSR, ROCK1 and RHG28.

Background Using human keratinocyte HaCaT cell line model, we screened for proteins that changed their content due to SDS exposure in non-toxic dose (25 μg/ml, as determined by the MTT assay and microscopic examination) during 48 h. Methods The altered level of proteins from HaCaT keratinocytes exposed to SDS was analyzed by LC-MS/MS approach and quantified using Progenesis LC software. Results The Pathview map of 131 upregulated proteins was built, and enhancement of glycolysis/gluconeogenesis was found. Conclusions The results of our study admit the possibility of promotion of the cutaneous neoplasia and/or the peculiarity of the response of immortalized keratinocytes to the SDS treatment and provide new insights into possible role of SDS as integrator of diverse signaling that influence cell fate decisions.

The relative differences between post-translational modifications (PTM) of proteins in blood plasma samples of patients with cerebral ischemia (CI) and healthy people were investigated using of the method of label-free comparative proteomic analysis based on the technology of tandem HPLC-MS/MS. For PTM detection we used multiple MS/MS search in the database Mascot for variable PTM and Progenesis LS-MS software. In the CI plasma samples, we observed an increase in the proportion of peptides with such PTM as phosphorylation of serine, threonine, and tyrosine, acetylation of lysine and protein N-term, ubiquitination of lysine and deamidation of glutamine related to clinically significant processes were revealed.

LC-MS/MS allows identification of thousands of proteins in the complex proteomes. However, a significant part of a proteome remains inaccessible for identification due to the absence or poor quality of MS/MS spectra. The method described herein allows identifying the desired proteins of human blood plasma by comparing aligned chromatographic data of digested by trypsin sample and the same sample with spikedin synthetic peptides. Identification of human blood plasma proteins is archived by assigning tandem mass spectra of spiked-in peptides to the corresponding aligned chromatographic peaks of proteolytic peptides. Using the described approach we have identified 19 low abundant proteins in human blood plasma, which corresponded to 19 synthetic peptides used in the study. SRM verification of the identifications with isotopically labelled standards (SIS) confirmed the presence in the plasma of above 17 proteins.

Proteome profiling of human testicular biopsies was performed using tandem mass spectrometry with electrospray ionization. Protein identification results were compared for the Mascot commercial search engine, the SearchGUI noncommercial package, and their analog IdentiProt based on the open-source IdentiPy algorithm ( http://hg.theorchromo.ru/identipy ). A feature of IdentiPy is an automatic optimization of MS/MS search parameters. A set of protein identifications obtained with IdentiPy was consequently greater by one third than the sets with the other search engines. For the first time, an IdentiPy/IdentiProt search was conducted within the Progenesis LC–MS framework, which allows spectrum alignment, and the proteome profile obtained with alignment was compared with that obtained using the ProteoWizard converter. A total of 16 human chromosome 18 proteins were identified, including the myelin basic protein, which is not characteristic of testicular tissue.

Proteome profiling of human testicular biopsies was performed using tandem mass spectrometry with electrospray ionization. Protein identification results were compared for the Mascot commercial search engine, the SearchGUI noncommercial package, and their analog IdentiProt based on the open-source IdentiPy algorithm (http://hg.theorchromo.ru/identipy). A feature of IdentiPy is an automatic optimization of MS/MS search parameters. A set of protein identifications obtained with IdentiPy was consequently greater by one third than the sets with the other search engines. For the first time, an IdentiPy/IdentiProt search was conducted within the Progenesis LC-MS framework, which allows spectrum alignment, and the proteome profile obtained with alignment was compared with that obtained using the ProteoWizard converter. A total of 16 human chromosome 18 proteins were identified, including the myelin basic protein, which is not characteristic of testicular tissue.

Blood plasma proteome in patients with cerebral ischemia and healthy individuals was studied using comparative proteomic analysis based on tandem HPLC-MS/MS. Mass spectra were analysed in an automated mode using Progenesis LS-MS software and 256 proteins were identified. Significant quantitative differences were revealed for 20 proteins. It was found that changes in the blood plasma proteome in subjects with cerebral ischemia involved a wide range of proteins: molecular chaperones, fibrinolysis, angiogenesis, and immune system proteins, proteins involved in homeostasis maintenance, cell differentiation and proliferation, regulators of apoptosis, and cytoskeleton proteins.

In this study, the proteomic approach based on high performance liquid chromatography connected with tandem mass spectrometry (LC-MS/MS) and bioinformatics analysis were applied to identify differentially abundant proteins in chorionic villus samples (CVS) from women with blighted ovum and normal pregnancy. We identified about 600 proteins in the solubilized fraction of CVS. Comparative proteomic analysis revealed differences in the content (Average Normalized Abundances) of 187 proteins in blighted ovum. These included 134 down-regulated proteins and 53 up-regulated proteins. According to bioinformatics analysis these proteins participate in a variety of metabolic processes, including alcohol and tricarboxylic acid metabolism, response to endoplasmic reticulum stress, small molecular catabolic process, cellular respiration, and others. Proteins that demonstrated growing content in blighted ovum were mainly encoded by genes located on chromosomes 7 and 16 whereas proteins which demonstrated reducing abundance were mainly encoded by genes located on chromosomes 1, 2, and 11. We also revealed changes in the content of proteins encoded by genes located on the human chromosome 18; they are involved in apoptotic and drug metabolic processes with an important role in early pregnancy loss. Our pilot results demonstrate the efficiency of the LC-MS/MS approach for detecting the differences at the qualitative and semi-quantitative levels in the protein profiles of the CVS at anembryonic pregnancy compared to normal gestation. We conclude that globally profiled and differentially regulated proteins of CVS are helpful in obtaining molecular insights into biological processes of the pregnancy pathology.

The effects of sodium dodecyl sulfate (25 mg/ml) and Triton X-100 (12.5 mg/ml and 25 mg/ml) on the HaCaT immortalized keratinocytes exposed to these surfactants for 48 h were studied. Using shotgun proteomics, a comparative analysis of the proteomic profiles of control and experimental cells after surfactants exposure was carried out. 260 common proteins were identified in control and experimental cells; 33 proteins were found in cells exposed to all three treatments, but not in control cells. These 33 proteins apparently reflect a nonspecific (universal) response of cells to toxic damage by the surfactants. These proteins are associated with activation of cell proliferation, changes in the functional activity of their ER and mitochondria, increased mRNA stability and activation of protein degradation processes in the cells. The possibility of using these proteins as a nonspecific parameter of cell response to cytotoxic damage is discussed. The mass spectrometry proteomics data ("raw", "mgf" and "xml" files) have been deposited to the ProteomeXchange Consortium via the PRIDE partner repository with the dataset identifiers PXD007789 and PXD007776.

Liquid chromatography-tandem mass spectrometry was used to analyze plasma proteins of volunteers (control) and patients with glioblastoma multiform (GBM). A database search was pre-set with a variable post-translational modification (PTM): phosphorylation, acetylation or ubiquitination. There were no significant differences between the control and the GBM groups regarding the number of protein identifications, sequence coverage or number of PTMs. However, in GBM plasma, we unambiguously observed a decreased fraction in post-translationally modified peptides identified with high quality. The disease-specific PTM patterns were extracted and mapped to the set of FDA-approved plasma protein markers. Decreases of 46% and 24% in the number of acetylated and ubiquitinated peptides, respectively, were observed in the GBM samples. Significance of capturing disease-associated patterns of protein modifications was envisaged.

Oxidative stress is a universal response of the skin cell damage of various origins. Sodium dodecyl sulfate (SDS, sodium lauryl sulfate) is an anionic surfactant commonly used as an emulsifying detergent in household cleaners. Sodium dodecyl sulfate is the reference compound for testing toxicity on cellular skin models. The effect of sodium dodecyl sulfate in sub toxic dose 25 μg/mL during 48 h on the protein profile of human keratinocytes HaCaT was studied by tandem mass spectrometry with electrospray ionization. In total, 1064 proteins were found in immortalized human keratinocytes HaCaT, of which about 80% were identified by two or more peptides. The change of the 217 proteins content was revealed, among them 39 according to Gene Ontology are associated with oxidative stress. It has been found that sodium dodecyl sulfate leads to a decrease in the number of proteins/peptides containing carboxymethylated and/or carboxyethylated lysine. We concluded about the promising of the cells redox-balance analysis at testing chemicals in the doses, which do not lead to a decrease in their viability. Possible involvement of sodium dodecyl sulfate in the development of cutaneous neoplasia is discussed.

Changes in the proteome of keratinocytes of immortalized HaCaT line exposed to cytotoxic substance Triton X-100 in concentrations of 12.5 and 25 μg/ml were studied by liquid chromatography combined with mass spectrometry. The appearance of proteins involved in the regulation of mitosis, RNA stability, and catabolic processes were detected; the number of apoptosis-associated proteins increased, while the number of proteins involved in differentiation and energy metabolism of keratinocytes decreased.

In the present study, we explored the technology of liquid chromatography-mass spectrometry (HPLC-MS/MS) for the proteome analysis of blood plasma of patients with early chronic cerebral ischemia. Analysis of mass-spectrometer data carried out in automatic mode using the software Progenesis LS-MS. As a result of this study identified 43 proteins. The differences identified in the study group compared with the control in 7 proteins. It was found that in the early stages of chronic cerebral ischemia proteome changes in blood plasma affect proteins related to the immune system, the system for the maintenance of hemostasis and lipid metabolism.