The Experts below are selected from a list of 312 Experts worldwide ranked by ideXlab platform
Mark D P Willcox - One of the best experts on this subject based on the ideXlab platform.
-
Method development for quantification of five tear proteins using selected reaction monitoring (SRM) mass spectrometry.
Investigative ophthalmology & visual science, 2014Co-Authors: Simin Masoudi, Ling Zhong, Mark J. Raftery, Fiona Stapleton, Mark D P WillcoxAbstract:PURPOSE To establish the use of selected reaction monitoring (SRM) mass spectrometry for quantification of tear proteins. METHODS Tear samples were collected on multiple occasions (7-10 days) from healthy subjects with contact lens wear (CL = 3) and without contact lens wear (NCL = 4). Tear proteins were denatured using 8M urea, reduced with iodoacetamide, precipitated by acetone, and digested using trypsin. Internal standards were included by adding isotopically-labelled standards of known concentrations to the samples. Lactoferrin, lysozyme, prolactin-induced protein, Lipocalin 1, and proline-rich protein 4 were quantified using liquid chromatography-triple quadruple mass spectrometry in conjunction with selected reaction monitoring. RESULTS The limits of quantification for the selected peptides were below 50 pg/μL. The recovery of peptides from spiked digested tears was greater than or equal to 56% and the coefficient of variation values were less than or equal to 16%. The concentration of lactoferrin (1.20 ± 0.77 μg/μL), lysozyme (2.11 ± 1.50 μg/μL), and Lipocalin-1 (1.75 ± 0.99 μg/μL) were consistent with previous ELISA studies. Tear levels of prolactin-induced protein (0.09 ± 0.06 μg/μL) and proline-rich 4 (0.80 ± 0.50 μg/μL) are reported here for the first time. CONCLUSIONS The SRM method can be used for simultaneous detection and quantification of selected proteins in low volumes of human tear samples (2.5 μL per sample) without prior purification of each protein component or need for antibodies.
-
Quantification of individual proteins in silicone hydrogel contact lens deposits.
Molecular vision, 2013Co-Authors: Negar Babaei Omali, Zhenjun Zhao, Hua Zhu, Daniel Tilia, Mark D P WillcoxAbstract:PURPOSE The aim of this study was to quantify specific proteins deposited on daily wear silicone hydrogel lenses used in combination with multipurpose disinfecting solutions (MPDSs) by applying multiple-reaction-monitoring mass spectrometry (MRM-MS). METHODS Balafilcon A or senofilcon A contact lenses used with different MPDSs on a daily wear schedule were collected. Each worn lens was extracted and then digested with trypsin. MRM-MS was applied to quantify the amounts of lysozyme, lactoferrin, Lipocalin-1, proline-rich protein-4, and keratin-1 in the extracts. RESULTS The amount of protein extracted from the contact lenses was affected by the individual wearers, lens material, and type of care system used. Higher amounts of proteins were extracted from lenses after wear when they were used with an MPDS containing polyhexamethylene biguanide (PHMB) and poloxamer 407 compared with MPDSs containing polyquaternium-1 (PQ-1)/alexidine dihydrochloride with Tetronic 904 or PQ-1/ PHMB with poloxamine and sulfobetaine (p < 0.05). There was a correlation between the amount of Lipocalin-1 or keratin-1 extracted from lenses and symptoms of ocular dryness. CONCLUSIONS The MRM-MS technique is a promising approach that could be used to reveal associations of individual proteins deposited on lenses with performance of contact lenses during wear.
-
Quantification of protein deposits on silicone hydrogel materials using stable-isotopic labeling and multiple reaction monitoring
Biofouling, 2012Co-Authors: Negar Babaei Omali, Jerome Ozkan, Ling Zhong, Zhenjun Zhao, Martin J Raftery, Mark D P WillcoxAbstract:This study was designed to use multiple reaction monitoring (MRM) for accurate quantification of contact lens protein deposits. Worn lenses used with a multipurpose disinfecting solution were collected after wear. Individual contact lenses were extracted and then digested with trypsin. MRM in conjunction with stable-isotope-labeled peptide standards was used for protein quantification. The results show that lysozyme was the major protein detected from both lens types. The amount of protein extracted from contact lenses was affected by the lens material. Except for keratin-1 (0.83 ± 0.61 vs 0.77 ± 0.20, p = 0.81) or proline rich protein-4 (0.11 ± 0.04 vs 0.15 ± 0.12, p = 0.97), the amounts of lysozyme, lactoferrin, or Lipocalin-1 extracted from balafilcon A lenses (12.9 ± 9.01, 0.84 ± 0.50 or 2.06 ± 1.6, respectively) were significantly higher than that extracted from senofilcon A lenses (0.88 ± 0.13, 0.50 ± 0.10 or 0.27 ± 0.23, respectively) (p
-
Post-translation modification of proteins in tears.
Electrophoresis, 2010Co-Authors: Jingjing You, Ling Zhong, Mark D P Willcox, Zhenjun Zhao, Anna Fitzgerald, Paul J. Cozzi, Peter Graham, Pamela J. Russell, Bradley J. Walsh, Valerie C. WasingerAbstract:This is the first 2-DE study using sequential dyes to analyse phospho-, glyco- and total tear protein profiles (Pro-Q Diamond for phosphoprotein, Pro-Q Emerald for glycoprotein and Sypro Ruby for total protein). This method minimised the gel-gel variations, allowing better comparisons among the three profiles and generated a whole map of PTM profiles of tear protein. A novel tear protein, dermcidin, was identified for the first time in this study. The identification of this antimicrobial protein suggests a new model of defence in tears. In addition, we are able to present the first experimental evidence of the presence of glycosylated Lipocalin 1 and cystatin S. Nucleobindin 2 was only detected using phospho staining, suggesting it is only phosphorylated in tears. This study provides the groundwork for understanding the PTM of tear proteins and consequently these methods could be useful in the search for biomarkers in tears.
-
Proteomic analysis of protein deposits on worn daily wear silicone hydrogel contact lenses.
Molecular vision, 2008Co-Authors: Zhenjun Zhao, Xiaojia Wei, Yulina Aliwarga, Nicole Carnt, Qian Garrett, Mark D P WillcoxAbstract:Purpose: Previous studies have demonstrated deposition of tear proteins onto worn contact lenses. In this study, we used proteomic techniques to analyze the protein deposits extracted from worn daily wear silicone hydrogel contact lenses in combination with different lens care solutions. Methods: Worn lenses were collected and protein deposits extracted using urea and surfactant. Protein extracts were desalted, concentrated, and then separated using one-dimensional gel electrophoresis. Individual protein components in extracts were identified using liquid chromatography combined with tandem mass spectrometry (LC-MS-MS) after trypsin digestion. Results: One-dimensional gel electrophoresis revealed that lysozyme and other small proteins (around 20 kDa) were the most abundant proteins in the extracts. LC-MS-MS revealed a wide array of proteins in lens extracts with lysozyme and Lipocalin 1 being the most commonly identified in deposit extracts. Conclusions: Worn contact lenses deposit a wide array of proteins from tear film and other sources. Protein deposit profiles varied and were specific for each contact lens material.
Thomas Hofmann - One of the best experts on this subject based on the ideXlab platform.
-
Quantitative proteomics and SWATH-MS to elucidate peri-receptor mechanisms in human salt taste sensitivity.
Food chemistry, 2018Co-Authors: Theresa Stolle, Freya Grondinger, Andreas Dunkel, Thomas HofmannAbstract:Abstract Recently, studies on human salt taste sensitivity demonstrated that sodium chloride (NaCl) sensitive and non-sensitive subjects differed in their salivary proteome and, in particular, in endopeptidase activity. In order to investigate individual’s NaCl sensitivity and the role of endoprotease activity in salt taste perception, 20 panellists were classified according to NaCl sensitivity and saliva samples collected. A targeted protein quantitation by means of selected-reaction-monitoring (SRM) mass spectrometry and stable-isotope incorporation revealed the joint abundance of lysozyme C and Lipocalin-1 to be indicative for non-sensitive subjects. Sensory studies performed after oral challenge with the serine-type endopeptidase trypsin demonstrated a salt enhancing effect which was assumed to be due to an in-vivo generation of salt-modulating peptides as shown by LC-SWATH-MS. Amongst those, the tetrapeptide PLWR was found to elicit salty taste enhancing activity above an extraordinarily low taste threshold concentration of 6.5 μmol/L.
-
Salivary Proteome Patterns Affecting Human Salt Taste Sensitivity
Journal of agricultural and food chemistry, 2017Co-Authors: Theresa Stolle, Freya Grondinger, Andreas Dunkel, Chen Meng, Guillaume Médard, Bernhard Kuster, Thomas HofmannAbstract:To investigate the role of perireceptor events in inter-individual variability in salt taste sensitivity, 31 volunteers were monitored in their detection functions for sodium chloride (NaCl) and classified into sensitive (0.6-1.7 mmol/L), medium-sensitive (1.8-6.9 mmol/L), and nonsensitive (7.0-11.2 mmol/L) subjects. Chemosensory intervention of NaCl-sensitive (S+) and nonsensitive (S-) panellists with potassium chloride, ammonium chloride, and sodium gluconate showed the salt taste sensitivity to be specific for NaCl. As no significant differences were found between S+ and S- subjects in salivary sodium and protein content, salivary proteome differences and their stimulus-induced dynamic changes were analyzed by tryptic digestion, iTRAQ labeling, and liquid chromatography-tandem mass spectrometry analysis. Differences in the salivary proteome between S+ and S- subjects were found primarily in resting saliva and were largely independent of the dynamic alterations observed upon salt stimulation. Gene ontology enrichment analysis of key proteins, i.e., immunoglobulin heavy constant y1, myeloblastin, cathepsin G, and kallikrein, revealed significantly increased serine-type endopeptidase activity for the S+ group, while the S- group exhibited augmented cysteine-type endopeptidase inhibitor activity by increased abundances in Lipocalin-1 and cystatin-D, -S, and -SN, respectively. As proteases have been suggested to facilitate transepithelial sodium transport by cleaving the y-subunit of the epithelial sodium channel (ENaC) and protease inhibitors have been shown to reduce ENaC-mediated sodium transport, the differentially modulated proteolytic activity patterns observed in vivo for S+ and S- subjects show evidence of them playing a crucial role in affecting human NaCl sensitivity.
-
Salivary Proteome Patterns Affecting Human Salt Taste Sensitivity
2017Co-Authors: Theresa Stolle, Freya Grondinger, Andreas Dunkel, Chen Meng, Bernhard Kuster, Guillaume Médard, Thomas HofmannAbstract:To investigate the role of perireceptor events in inter-individual variability in salt taste sensitivity, 31 volunteers were monitored in their detection functions for sodium chloride (NaCl) and classified into sensitive (0.6–1.7 mmol/L), medium-sensitive (1.8–6.9 mmol/L), and nonsensitive (7.0–11.2 mmol/L) subjects. Chemosensory intervention of NaCl-sensitive (S+) and nonsensitive (S–) panellists with potassium chloride, ammonium chloride, and sodium gluconate showed the salt taste sensitivity to be specific for NaCl. As no significant differences were found between S+ and S– subjects in salivary sodium and protein content, salivary proteome differences and their stimulus-induced dynamic changes were analyzed by tryptic digestion, iTRAQ labeling, and liquid chromatography–tandem mass spectrometry analysis. Differences in the salivary proteome between S+ and S– subjects were found primarily in resting saliva and were largely independent of the dynamic alterations observed upon salt stimulation. Gene ontology enrichment analysis of key proteins, i.e., immunoglobulin heavy constant y1, myeloblastin, cathepsin G, and kallikrein, revealed significantly increased serine-type endopeptidase activity for the S+ group, while the S– group exhibited augmented cysteine-type endopeptidase inhibitor activity by increased abundances in Lipocalin-1 and cystatin-D, -S, and -SN, respectively. As proteases have been suggested to facilitate transepithelial sodium transport by cleaving the y-subunit of the epithelial sodium channel (ENaC) and protease inhibitors have been shown to reduce ENaC-mediated sodium transport, the differentially modulated proteolytic activity patterns observed in vivo for S+ and S– subjects show evidence of them playing a crucial role in affecting human NaCl sensitivity
Theresa Stolle - One of the best experts on this subject based on the ideXlab platform.
-
Quantitative proteomics and SWATH-MS to elucidate peri-receptor mechanisms in human salt taste sensitivity.
Food chemistry, 2018Co-Authors: Theresa Stolle, Freya Grondinger, Andreas Dunkel, Thomas HofmannAbstract:Abstract Recently, studies on human salt taste sensitivity demonstrated that sodium chloride (NaCl) sensitive and non-sensitive subjects differed in their salivary proteome and, in particular, in endopeptidase activity. In order to investigate individual’s NaCl sensitivity and the role of endoprotease activity in salt taste perception, 20 panellists were classified according to NaCl sensitivity and saliva samples collected. A targeted protein quantitation by means of selected-reaction-monitoring (SRM) mass spectrometry and stable-isotope incorporation revealed the joint abundance of lysozyme C and Lipocalin-1 to be indicative for non-sensitive subjects. Sensory studies performed after oral challenge with the serine-type endopeptidase trypsin demonstrated a salt enhancing effect which was assumed to be due to an in-vivo generation of salt-modulating peptides as shown by LC-SWATH-MS. Amongst those, the tetrapeptide PLWR was found to elicit salty taste enhancing activity above an extraordinarily low taste threshold concentration of 6.5 μmol/L.
-
Salivary Proteome Patterns Affecting Human Salt Taste Sensitivity
Journal of agricultural and food chemistry, 2017Co-Authors: Theresa Stolle, Freya Grondinger, Andreas Dunkel, Chen Meng, Guillaume Médard, Bernhard Kuster, Thomas HofmannAbstract:To investigate the role of perireceptor events in inter-individual variability in salt taste sensitivity, 31 volunteers were monitored in their detection functions for sodium chloride (NaCl) and classified into sensitive (0.6-1.7 mmol/L), medium-sensitive (1.8-6.9 mmol/L), and nonsensitive (7.0-11.2 mmol/L) subjects. Chemosensory intervention of NaCl-sensitive (S+) and nonsensitive (S-) panellists with potassium chloride, ammonium chloride, and sodium gluconate showed the salt taste sensitivity to be specific for NaCl. As no significant differences were found between S+ and S- subjects in salivary sodium and protein content, salivary proteome differences and their stimulus-induced dynamic changes were analyzed by tryptic digestion, iTRAQ labeling, and liquid chromatography-tandem mass spectrometry analysis. Differences in the salivary proteome between S+ and S- subjects were found primarily in resting saliva and were largely independent of the dynamic alterations observed upon salt stimulation. Gene ontology enrichment analysis of key proteins, i.e., immunoglobulin heavy constant y1, myeloblastin, cathepsin G, and kallikrein, revealed significantly increased serine-type endopeptidase activity for the S+ group, while the S- group exhibited augmented cysteine-type endopeptidase inhibitor activity by increased abundances in Lipocalin-1 and cystatin-D, -S, and -SN, respectively. As proteases have been suggested to facilitate transepithelial sodium transport by cleaving the y-subunit of the epithelial sodium channel (ENaC) and protease inhibitors have been shown to reduce ENaC-mediated sodium transport, the differentially modulated proteolytic activity patterns observed in vivo for S+ and S- subjects show evidence of them playing a crucial role in affecting human NaCl sensitivity.
-
Salivary Proteome Patterns Affecting Human Salt Taste Sensitivity
2017Co-Authors: Theresa Stolle, Freya Grondinger, Andreas Dunkel, Chen Meng, Bernhard Kuster, Guillaume Médard, Thomas HofmannAbstract:To investigate the role of perireceptor events in inter-individual variability in salt taste sensitivity, 31 volunteers were monitored in their detection functions for sodium chloride (NaCl) and classified into sensitive (0.6–1.7 mmol/L), medium-sensitive (1.8–6.9 mmol/L), and nonsensitive (7.0–11.2 mmol/L) subjects. Chemosensory intervention of NaCl-sensitive (S+) and nonsensitive (S–) panellists with potassium chloride, ammonium chloride, and sodium gluconate showed the salt taste sensitivity to be specific for NaCl. As no significant differences were found between S+ and S– subjects in salivary sodium and protein content, salivary proteome differences and their stimulus-induced dynamic changes were analyzed by tryptic digestion, iTRAQ labeling, and liquid chromatography–tandem mass spectrometry analysis. Differences in the salivary proteome between S+ and S– subjects were found primarily in resting saliva and were largely independent of the dynamic alterations observed upon salt stimulation. Gene ontology enrichment analysis of key proteins, i.e., immunoglobulin heavy constant y1, myeloblastin, cathepsin G, and kallikrein, revealed significantly increased serine-type endopeptidase activity for the S+ group, while the S– group exhibited augmented cysteine-type endopeptidase inhibitor activity by increased abundances in Lipocalin-1 and cystatin-D, -S, and -SN, respectively. As proteases have been suggested to facilitate transepithelial sodium transport by cleaving the y-subunit of the epithelial sodium channel (ENaC) and protease inhibitors have been shown to reduce ENaC-mediated sodium transport, the differentially modulated proteolytic activity patterns observed in vivo for S+ and S– subjects show evidence of them playing a crucial role in affecting human NaCl sensitivity
Jing Zhang - One of the best experts on this subject based on the ideXlab platform.
-
Increased serum levels of Lipocalin-1 and -2 in patients with stable chronic obstructive pulmonary disease.
International journal of chronic obstructive pulmonary disease, 2014Co-Authors: Xiao-ru Wang, Shui Gao, Wei Xia, Kun Gao, Qing-hua Kong, Jing ZhangAbstract:Despite a number of studies on biomarkers in chronic obstructive pulmonary disease (COPD), only a few disease-related markers have been identified, yet we still have no satisfactory markers specific to innate immune system and neutrophil activation, which is essential in airway inflammation in COPD. Recent biological studies indicated that Lipocalins (LCNs) might be involved in airway inflammation and innate immunity; however, results from available studies on the association of LCNs with COPD are not consistent. We carried out a multicenter prospective observational cohort study to investigate the differences in serum levels of LCN1 and LCN2 between subjects with COPD (n=58) and healthy controls (n=29). Several validated inflammatory markers, including C-reactive protein, tumor necrosis factor-α, interleukin-6, and interleukin-8, were measured. The correlation of LCN1 and LCN2 with clinical features such as smoking habits, lung function, symptoms, and disease category was also analyzed. When comparing with healthy controls, serum levels of LCN1 (66.35±20.26 ng/mL versus 41.16±24.19 ng/mL, P
-
increased serum levels of Lipocalin 1 and 2 in patients with stable chronic obstructive pulmonary disease
International Journal of Chronic Obstructive Pulmonary Disease, 2014Co-Authors: Xiao-ru Wang, Shui Gao, Wei Xia, Kun Gao, Qing-hua Kong, Jing Zhang, Chunxue BaiAbstract:Despite a number of studies on biomarkers in chronic obstructive pulmonary disease (COPD), only a few disease-related markers have been identified, yet we still have no satisfactory markers specific to innate immune system and neutrophil activation, which is essential in airway inflammation in COPD. Recent biological studies indicated that Lipocalins (LCNs) might be involved in airway inflammation and innate immunity; however, results from available studies on the association of LCNs with COPD are not consistent. We carried out a multicenter prospective observational cohort study to investigate the differences in serum levels of LCN1 and LCN2 between subjects with COPD (n=58) and healthy controls (n=29). Several validated inflammatory markers, including C-reactive protein, tumor necrosis factor-α, interleukin-6, and interleukin-8, were measured. The correlation of LCN1 and LCN2 with clinical features such as smoking habits, lung function, symptoms, and disease category was also analyzed. When comparing with healthy controls, serum levels of LCN1 (66.35±20.26 ng/mL versus 41.16±24.19 ng/mL, P<0.001) and LCN2 (11.29±3.92 ng/mL versus 6.09±5.13 ng/mL, P<0.001) were both elevated in subjects with COPD after adjusting for age, sex, smoking habits, and inflammatory biomarkers. Smoking history and tobacco exposure, as quantified by pack-year, had no impact on systemic expressions of LCN1 and LCN2 in our study. Blood levels of LCN1 and LCN2, respectively, were negatively correlated to COPD Assessment Test and Modified Medical British Research Council score (P<0.001). Disease category by Global Initiative for Chronic Obstructive Lung Disease grade 1-4 or group A-D was not associated with levels of LCNs. Patient-reported exacerbations and body mass index were also tested, but no relationship with LCNs was found. In summary, serum concentrations of LCN1 and LCN2 were both elevated in patients with COPD, with their levels correlating to COPD Assessment Test and Modified Medical British Research Council score. These findings warrant large-scale and longitudinal studies to validate LCNs as circulating biomarkers for COPD.
Zhenjun Zhao - One of the best experts on this subject based on the ideXlab platform.
-
Quantification of individual proteins in silicone hydrogel contact lens deposits.
Molecular vision, 2013Co-Authors: Negar Babaei Omali, Zhenjun Zhao, Hua Zhu, Daniel Tilia, Mark D P WillcoxAbstract:PURPOSE The aim of this study was to quantify specific proteins deposited on daily wear silicone hydrogel lenses used in combination with multipurpose disinfecting solutions (MPDSs) by applying multiple-reaction-monitoring mass spectrometry (MRM-MS). METHODS Balafilcon A or senofilcon A contact lenses used with different MPDSs on a daily wear schedule were collected. Each worn lens was extracted and then digested with trypsin. MRM-MS was applied to quantify the amounts of lysozyme, lactoferrin, Lipocalin-1, proline-rich protein-4, and keratin-1 in the extracts. RESULTS The amount of protein extracted from the contact lenses was affected by the individual wearers, lens material, and type of care system used. Higher amounts of proteins were extracted from lenses after wear when they were used with an MPDS containing polyhexamethylene biguanide (PHMB) and poloxamer 407 compared with MPDSs containing polyquaternium-1 (PQ-1)/alexidine dihydrochloride with Tetronic 904 or PQ-1/ PHMB with poloxamine and sulfobetaine (p < 0.05). There was a correlation between the amount of Lipocalin-1 or keratin-1 extracted from lenses and symptoms of ocular dryness. CONCLUSIONS The MRM-MS technique is a promising approach that could be used to reveal associations of individual proteins deposited on lenses with performance of contact lenses during wear.
-
Quantification of protein deposits on silicone hydrogel materials using stable-isotopic labeling and multiple reaction monitoring
Biofouling, 2012Co-Authors: Negar Babaei Omali, Jerome Ozkan, Ling Zhong, Zhenjun Zhao, Martin J Raftery, Mark D P WillcoxAbstract:This study was designed to use multiple reaction monitoring (MRM) for accurate quantification of contact lens protein deposits. Worn lenses used with a multipurpose disinfecting solution were collected after wear. Individual contact lenses were extracted and then digested with trypsin. MRM in conjunction with stable-isotope-labeled peptide standards was used for protein quantification. The results show that lysozyme was the major protein detected from both lens types. The amount of protein extracted from contact lenses was affected by the lens material. Except for keratin-1 (0.83 ± 0.61 vs 0.77 ± 0.20, p = 0.81) or proline rich protein-4 (0.11 ± 0.04 vs 0.15 ± 0.12, p = 0.97), the amounts of lysozyme, lactoferrin, or Lipocalin-1 extracted from balafilcon A lenses (12.9 ± 9.01, 0.84 ± 0.50 or 2.06 ± 1.6, respectively) were significantly higher than that extracted from senofilcon A lenses (0.88 ± 0.13, 0.50 ± 0.10 or 0.27 ± 0.23, respectively) (p
-
Post-translation modification of proteins in tears.
Electrophoresis, 2010Co-Authors: Jingjing You, Ling Zhong, Mark D P Willcox, Zhenjun Zhao, Anna Fitzgerald, Paul J. Cozzi, Peter Graham, Pamela J. Russell, Bradley J. Walsh, Valerie C. WasingerAbstract:This is the first 2-DE study using sequential dyes to analyse phospho-, glyco- and total tear protein profiles (Pro-Q Diamond for phosphoprotein, Pro-Q Emerald for glycoprotein and Sypro Ruby for total protein). This method minimised the gel-gel variations, allowing better comparisons among the three profiles and generated a whole map of PTM profiles of tear protein. A novel tear protein, dermcidin, was identified for the first time in this study. The identification of this antimicrobial protein suggests a new model of defence in tears. In addition, we are able to present the first experimental evidence of the presence of glycosylated Lipocalin 1 and cystatin S. Nucleobindin 2 was only detected using phospho staining, suggesting it is only phosphorylated in tears. This study provides the groundwork for understanding the PTM of tear proteins and consequently these methods could be useful in the search for biomarkers in tears.
-
Proteomic analysis of protein deposits on worn daily wear silicone hydrogel contact lenses.
Molecular vision, 2008Co-Authors: Zhenjun Zhao, Xiaojia Wei, Yulina Aliwarga, Nicole Carnt, Qian Garrett, Mark D P WillcoxAbstract:Purpose: Previous studies have demonstrated deposition of tear proteins onto worn contact lenses. In this study, we used proteomic techniques to analyze the protein deposits extracted from worn daily wear silicone hydrogel contact lenses in combination with different lens care solutions. Methods: Worn lenses were collected and protein deposits extracted using urea and surfactant. Protein extracts were desalted, concentrated, and then separated using one-dimensional gel electrophoresis. Individual protein components in extracts were identified using liquid chromatography combined with tandem mass spectrometry (LC-MS-MS) after trypsin digestion. Results: One-dimensional gel electrophoresis revealed that lysozyme and other small proteins (around 20 kDa) were the most abundant proteins in the extracts. LC-MS-MS revealed a wide array of proteins in lens extracts with lysozyme and Lipocalin 1 being the most commonly identified in deposit extracts. Conclusions: Worn contact lenses deposit a wide array of proteins from tear film and other sources. Protein deposit profiles varied and were specific for each contact lens material.