| 1. |
|
|
| 2. |
- Ali, Neserin, et al.
(författare)
-
Analysis of nanoparticle-protein coronas formed in vitro between nanosized welding particles and nasal lavage proteins.
- 2016
-
Ingår i: Nanotoxicology. - : Taylor & Francis. - 1743-5390 .- 1743-5404. ; 10:2, s. 226-234
-
Tidskriftsartikel (refereegranskat)abstract
- Welding fumes include agglomerated particles built up of primary nanoparticles. Particles inhaled through the nose will to some extent be deposited in the protein-rich nasal mucosa, and a protein corona will be formed around the particles. The aim was to identify the protein corona formed between nasal lavage proteins and four types of particles with different parameters. Two of the particles were formed and collected during welding and two were manufactured iron oxides. When nasal lavage proteins were added to the particles, differences were observed in the sizes of the aggregates that were formed. Measurements showed that the amount of protein bound to particles correlated with the relative size increase of the aggregates, suggesting that the surface area was associated with the binding capacity. However, differences in aggregate sizes were detected when nasal proteins were added to UFWF and Fe2O3 particles (having similar agglomerated size) suggesting that yet parameters other than size determine the binding. Relative quantitative mass spectrometric and gel-based analyses showed differences in the protein content of the coronas. High-affinity proteins were further assessed for network interactions. Additional experiments showed that the inhibitory function of secretory leukocyte peptidase inhibitor, a highly abundant nasal protein, was influenced by particle binding suggesting that an understanding of protein function following particle binding is necessary to properly evaluate pathophysiological events. Our results underscore the importance of including particles collected from real working environments when studying the toxic effects of particles because these effects might be mediated by the protein corona.
|
|
| 3. |
- Ali, Neserin, et al.
(författare)
-
Comprehensive proteome analysis of nasal lavage samples after controlled exposure to welding nanoparticles shows an induced acute phase and a nuclear receptor, LXR/RXR, activation that influence the status of the extracellular matrix
- 2018
-
Ingår i: Clinical Proteomics. - : Springer Science and Business Media LLC. - 1542-6416 .- 1559-0275. ; 15:1
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Epidemiological studies have shown that many welders experience respiratory symptoms. During the welding process a large number of airborne nanosized particles are generated, which might be inhaled and deposited in the respiratory tract. Knowledge of the underlying mechanisms behind observed symptoms is still partly lacking, although inflammation is suggested to play a central role. The aim of this study was to investigate the effects of welding fume particle exposure on the proteome expression level in welders suffering from respiratory symptoms, and changes in protein mediators in nasal lavage samples were analyzed. Such mediators will be helpful to clarify the pathomechanisms behind welding fume particle-induced effects. Methods: In an exposure chamber, 11 welders with work-related symptoms in the lower airways during the last month were exposed to mild-steel welding fume particles (1 mg/m3) and to filtered air, respectively, in a double-blind manner. Nasal lavage samples were collected before, immediately after, and the day after exposure. The proteins in the nasal lavage were analyzed with two different mass spectrometry approaches, label-free discovery shotgun LC-MS/MS and a targeted selected reaction monitoring LC-MS/MS analyzing 130 proteins and four in vivo peptide degradation products. Results: The analysis revealed 30 significantly changed proteins that were associated with two main pathways; activation of acute phase response signaling and activation of LXR/RXR, which is a nuclear receptor family involved in lipid signaling. Connective tissue proteins and proteins controlling the degradation of such tissues, including two different matrix metalloprotease proteins, MMP8 and MMP9, were among the significantly changed enzymes and were identified as important key players in the pathways. Conclusion: Exposure to mild-steel welding fume particles causes measurable changes on the proteome level in nasal lavage matrix in exposed welders, although no clinical symptoms were manifested. The results suggested that the exposure causes an immediate effect on the proteome level involving acute phase proteins and mediators regulating lipid signaling. Proteases involved in maintaining the balance between the formation and degradation of extracellular matrix proteins are important key proteins in the induced effects.
|
|
| 4. |
- Jeppsson, Marina, et al.
(författare)
-
Identification of Covalent Binding Sites of Phthalic Anhydride in Human Hemoglobin.
- 2008
-
Ingår i: Chemical Research in Toxicology. - : American Chemical Society (ACS). - 1520-5010 .- 0893-228X. ; Oct 3, s. 2156-2163
-
Tidskriftsartikel (refereegranskat)abstract
- Phthalic anhydride (PA) is a reactive low molecular weight compound used in the chemical industry. The exposure of PA may lead to work-related airway diseases such as rhinitis, chronic bronchitis, and asthma. The exposure gives rise to an increase in hapten-specific IgG antibodies in workers but with a low presence of specific IgE antibodies. In this study, the binding of PA to human hemoglobin (Hb) in vitro was investigated. Trypsin and Pronase E digestion, LC, LC/MS/MS, GC/MS analysis, and nanoelectrospray hybrid quadrupole time-of-flight MS were used to identify the adducted amino acids of the synthesized PA-Hb conjugates. In the conjugate with the molar ratio 1:0.1, a total of six adducted amino acids were identified. N-Terminal valine was found adducted in both the alpha- and the beta-chains as well as a total of four lysines, Val 1, Lys 16, and Lys 61 on the alpha-chain and Val 1, Lys 66, and Lys 144 on the beta-chain. Two types of lysine adducts were found, a phthalamide and a phthalimide. It was also found that PA differs in its binding site as compared to hexahydrophthalic anhydride. The result of this study suggests several interesting applications of biological monitoring.
|
|
| 5. |
- Jeppsson, Marina, et al.
(författare)
-
Methylhexahydrophthalic anhydride adducted albumin tryptic peptides in nasal lavage fluid.
- 2009
-
Ingår i: Inhalation Toxicology. - : Informa UK Limited. - 0895-8378 .- 1091-7691. ; 21:12, s. 1013-1020
-
Tidskriftsartikel (refereegranskat)abstract
- Methylhexahydrophthalic anhydride (MHHPA) is a reactive, low molecular weight chemical used in products such as plastics, paints, and electronic components. Exposure to MHHPA may lead to work-related airway diseases such as rhinitis, conjunctivitis, and asthma. Twelve subjects employed at a plant manufacturing electrical capacitors using MHHPA were included in this study. Nasal lavages were collected from subjects before work Monday morning and after work Tuesday afternoon. The levels of MHHPA adducted to serum albumin were analyzed with a straightforward work-up method. The samples were trypsinated before being analyzed with a liquid chromatography-triple quadrupole mass spectrometer. The mass spectrometer was run using selected reaction monitoring for six adducted peptides. Also, some biomarkers of effect (albumin, total protein, eosinophil cationic protein, and tryptase) were analyzed in nasal lavages. Furthermore, the metabolite MHHP acid in urine after work on Tuesday was analyzed by gas chromatography-mass spectrometry. Symptoms from the airways and the eyes and sensitization were registered. The main result of this study is that protein adducts can be analyzed in vivo after low occupational exposures to MHHPA. The results also show a correlation between adducted peptides and albumin in nasal lavage. Furthermore, there may be a difference in the potential to induce hyperresponsiveness between adducts bound to different amino acids.
|
|
| 6. |
- Johannesson, Gunvor, et al.
(författare)
-
Evaluation of an immunoaffinity extraction column for enrichment of adducts between human serum albumin and hexahydrophthalic anhydride in plasma.
- 2008
-
Ingår i: Biomedical Chromatography. - : Wiley. - 0269-3879 .- 1099-0801. ; 22:3, s. 327-332
-
Tidskriftsartikel (refereegranskat)abstract
- An immunoaffinity extraction (IAE) column was prepared for extraction of adducts between human serum albumin (HSA) and hexahydrophthalic anhydride (HHPA). HHPA is a strong sensitizer inducing immunoglobulin E antibodies in vivo. Polyclonal antibodies from a rabbit immunized with keyhole limpet hemocyananin-HHPA conjugate were purified using a Protein A Sepharose gel. To obtain antibodies with optimal affinity towards HHPA-protein adducts, HHPA-specific antibodies were selected using an N-hydroxysuccinimide-Sepharose column coupled with albumin-HHPA conjugate. Antibodies eluted from this column at pH 2.2 were selected to prepare the IAE column. The column was evaluated using 2 mL plasma spiked with HSA-HHPA conjugate. The column was eluted with glycine buffer at pH 2.0. The conjugates in the eluate were hydrolyzed to the corresponding HHP acid and quantified by mass spectrometry. The average recovery of HHPA adducts in 11 experiments was 68% with a coefficient of variation (CV) of 7%. The column's capacity to bind protein-HHPA adducts was found to be linear in the range of 0.15-1.2 nmol conjugate. The evaluation showed that the IAE column had adequate affinity towards the HHPA adducts and that the adducts could be extracted with good recovery and precision from a large volume of plasma.
|
|
| 7. |
|
|
| 8. |
- Kåredal, Monica, et al.
(författare)
-
Determination of hexahydrophthalic anhydride adducts to human serum albumin
- 2003
-
Ingår i: Biomarkers. - : Informa UK Limited. - 1366-5804 .- 1354-750X. ; 8:5, s. 343-359
-
Tidskriftsartikel (refereegranskat)abstract
- Hexahydrophthalic anhydride (HHPA) is a highly sensitizing industrial chemical that is known to covalently bind to endogenous proteins. The aim of this study was to determine the binding sites of HHPA to human serum albumin (HSA). Conjugates between HSA and HHPA, at two different molar ratios, were synthesized under physiological conditions. The conjugates were digested with trypsin and Pronase E to obtain specific peptides and amino acids, which were separated by liquid chromatography (LC). Fractions containing modified peptides were detected through quantification of hydrolysable HHPA using LC coupled to a triple quadrupole mass spectrometer with electrospray ionization. Modified residues in albumin were identified by sequence analyses using nanoelectrospray quadrupole time-of-flight mass spectrometry. A total of 36 HHPA adducts were found in the HSA - HHPA conjugate with 10 times molar excess of added HHPA. In the conjugate with a molar ratio of 1: 0.1 of added HHPA, seven HHPA adducts were found bound to Lys(137) (domain IB), Lys(190), Lys(199) and Lys(212) (domain IIA), Lys(351) (domain IIB), and Lys(432) and Lys(436) (domain IIIA). Moreover, several of these adducted albumin peptides were detected in nasal lavage fluid from one volunteer exposed to HHPA. The binding sites of HHPA to HSA have been determined, thus identifying potential allergenic chemical structures. This knowledge generates the possibility of developing methods for the biological monitoring of HHPA exposure by analysing tryptic peptides including these binding sites.
|
|
| 9. |
- Kåredal, Monica, et al.
(författare)
-
Mass spectrometric characterization of human hemoglobin adducts formed in vitro by hexahydrophthalic anhydride.
- 2002
-
Ingår i: Chemical Research in Toxicology. - : American Chemical Society (ACS). - 1520-5010 .- 0893-228X. ; 15:4, s. 562-569
-
Tidskriftsartikel (refereegranskat)abstract
- Primary structural information of anhydride binding to endogenous proteins is of interest in order to determine the mechanism causing the type-I allergy seen in many anhydride-exposed workers. In addition, studies on specific protein adducts may generate new methods for biological monitoring. In this study, the binding of hexahydrophthalic anhydride (HHPA) to human hemoglobin (Hb) in vitro was investigated. The in vitro synthesized conjugates were analyzed using a hybrid quadrupole-time-of-flight mass spectrometer (Q-TOF) with electrospray ionization (ESI) to determine the number of HHPA adducts per Hb molecule. Structural information on the locations of the adducts was obtained through nanospray Q-TOF, liquid chromatography-ESI mass spectrometric analysis, and gas chromatography/mass spectrometric analysis of Pronase E and tryptic digests. Up to six adducts were found on the alpha-chain and five on the beta-chain. The HHPA-adducts were localized to the N-terminal valine of the alpha- and beta-chains of Hb and to lysine residues at positions 7, 11, 16, and 40 of the alpha-chain and 8, 17, 59, 66, and 144 of the beta-chain. These results will constitute a basis for studies on structure-activity relationships as well as for development of methods for biological monitoring of acid anhydrides.
|
|
| 10. |
- Kåredal, Monica, et al.
(författare)
-
Mass spectrometric monitoring of in vitro formed ad ducts between hexahydrophthalic anhydride (HHPA) and cysteine and lysine
- 2002
-
Ingår i: Proceedings 50th ASMS Conference on Mass Spectrmetry and Allied Topics. ; , s. 325-326
-
Konferensbidrag (refereegranskat)abstract
- The in vitro formed adducts between hexahydrophthalic anhydride (HHPA) and cysteine and lysine were monitored by mass spectrometry. Freshly synthesized N-acetyl-S-hexahydrophthaloyl-L-cysteine was dissolved in dry acetonitrile and added to a solution of N-acetyl-L-lysine in 0.1 M sodium phosphate buffer (pH 7.4) an incubated at 37°C. The reactions were monitored by LC/MS on a triple quadrupole mass spectrometer with electrospray ionization coupled to a HPLC system from Perkin Elmer. The results show that there was a rapid rearrangement of HHPA from most of the cysteines to the lysines, and that HHPA-adducts of cysteine will be transferred to lysine when encountered.
|
|
