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Ibrahim A, Abd-Elrasoul MAA, Sabra MS. Impact of pH modification of the empirically used tobramycin ophthalmic solution on MIC90 concentration in tears and aqueous humor of donkeys (Equus asinus). BMC Vet Res 2024; 20:218. [PMID: 38778405 PMCID: PMC11112948 DOI: 10.1186/s12917-024-04072-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Accepted: 05/10/2024] [Indexed: 05/25/2024] Open
Abstract
BACKGROUND Commercial tobramycin ophthalmic solution is frequently used empirically to treat ocular disorders in equines, despite being primarily formulated for use in humans. It has been noted that tobramycin MIC90 concentration (minimal inhibitory concentration to 90% of microbial growth) rapidly declined following topical administration. It is hypothesized that adjustment of the pH of the empirically used tobramycin ophthalmic solution -prepared for human use- with the pH of the tears of donkeys, could increase the bioavailability of the drug and subsequently improve its penetration to the aqueous humor. Therefore, this study aimed to evaluate the impact of pH adjustment of the empirically used tobramycin ophthalmic solution on MIC90 concentration in tears and aqueous humor of donkeys (Equus asinus). The study was conducted on six (n = 6) clinically healthy donkeys. In each donkey, one eye was randomly selected to receive 210 µg tobramycin of the commercial tobramycin (CT) and used as a positive control (C group, n = 6). The other eye (treated eye) received 210 µg of the modified tobramycin ophthalmic solution (MT) (T group, n = 6). Tears and aqueous humor samples were collected 5-, 10-, 15-, 30- min, and 1-, 2-, 4-, and 6 h post-instillation. RESULTS Modifying the pH of the empirically used commercial tobramycin ophthalmic solution in donkeys at a pH of 8.26 enhanced the drug's bioavailability. The MIC90 of the most hazardous bacteria isolated from equines' eyes such as Pseudomonas aeruginosa (MIC90 = 128 µg/ml) and Staphylococcus aureus (MIC90 = 256 µg/ml) was covered early (5 min post-instillation) and over a longer period in donkey tears (239-342 min) and aqueous humor (238-330 min) with the modified tobramycin solution. CONCLUSIONS Adjustment of the pH of the commercial tobramycin ophthalmic solution, empirically used by veterinarians to treat donkeys' ophthalmic infections at a pH of 8.26, isotonic with the donkeys' tears pH, resulting in higher concentrations of tobramycin in tears and aqueous humor for a longer time.
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Affiliation(s)
- Ahmed Ibrahim
- Veterinary Teaching Hospital, Faculty of Veterinary Medicine, Assiut University, Assiut, 71526, Egypt.
| | | | - Mahmoud S Sabra
- Department of Pharmacology, Faculty of Veterinary Medicine, Assiut University, Assiut, 71526, Egypt
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2
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Boychev N, Lee S, Yeung V, Ross AE, Kuang L, Chen L, Dana R, Ciolino JB. Contact lenses as novel tear fluid sampling vehicles for total RNA isolation, precipitation, and amplification. Sci Rep 2024; 14:11727. [PMID: 38778161 PMCID: PMC11111455 DOI: 10.1038/s41598-024-62215-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2024] [Accepted: 05/14/2024] [Indexed: 05/25/2024] Open
Abstract
The tear fluid is a readily accessible, potential source for biomarkers of disease and could be used to monitor the ocular response to contact lens (CL) wear or ophthalmic pathologies treated by therapeutic CLs. However, the tear fluid remains largely unexplored as a biomarker source for RNA-based molecular analyses. Using a rabbit model, this study sought to determine whether RNA could be collected from commercial CLs and whether the duration of CL wear would impact RNA recovery. The results were referenced to standardized strips of filtered paper (e.g., Shirmer Strips) placed in the inferior fornix. By performing total RNA isolation, precipitation, and amplification with commercial kits and RT-PCR methods, CLs were found to have no significant differences in RNA concentration and purity compared to Schirmer Strips. The study also identified genes that could be used to normalize RNA levels between tear samples. Of the potential control genes or housekeeping genes, GAPDH was the most stable. This study, which to our knowledge has never been done before, provides a methodology for the detection of RNA and gene expression changes from tear fluid that could be used to monitor or study eye diseases.
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Affiliation(s)
- Nikolay Boychev
- Department of Ophthalmology, Schepens Eye Research Institute, Massachusetts Eye and Ear, and Harvard Medical School, Boston, USA.
| | - Seokjoo Lee
- Department of Ophthalmology, Schepens Eye Research Institute, Massachusetts Eye and Ear, and Harvard Medical School, Boston, USA
| | - Vincent Yeung
- Department of Ophthalmology, Schepens Eye Research Institute, Massachusetts Eye and Ear, and Harvard Medical School, Boston, USA
| | - Amy E Ross
- Department of Ophthalmology, Schepens Eye Research Institute, Massachusetts Eye and Ear, and Harvard Medical School, Boston, USA
| | - Liangju Kuang
- Department of Ophthalmology, Schepens Eye Research Institute, Massachusetts Eye and Ear, and Harvard Medical School, Boston, USA
| | - Lin Chen
- Department of Optometry and Visual Science, West China Hospital, Sichuan University, Chengdu, Sichuan, China
- Department of Ophthalmology, Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou, China
| | - Reza Dana
- Department of Ophthalmology, Schepens Eye Research Institute, Massachusetts Eye and Ear, and Harvard Medical School, Boston, USA
| | - Joseph B Ciolino
- Department of Ophthalmology, Schepens Eye Research Institute, Massachusetts Eye and Ear, and Harvard Medical School, Boston, USA
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3
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Sharma S, Belenje A, Takkar B, Narula R, Rathi VM, Tyagi M, Rani PK, Narayanan R, Kaur I. Tear Protein Markers for Diabetic Retinopathy and Diabetic Macular Edema - Towards an Early Diagnosis and Better Prognosis. Semin Ophthalmol 2024:1-11. [PMID: 38643349 DOI: 10.1080/08820538.2024.2342266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Accepted: 04/01/2024] [Indexed: 04/22/2024]
Abstract
BACKGROUND Diabetic eye disease is a highly prevalent and sight-threatening disorder. It is a disease of neuro-vascular unit of the retina, if left untreated can cause blindness. Therapeutic approaches followed for its treatment can only restrict the progression of the disease with highly variable results. There is no known biomarker for an early diagonsis of this disease, therefore by the time it is detected it goes beyond repair. This creates a massive demand for development of such biomarkers that help detect disease in its earlier stages. METHODS PUBMED (https://pubmed.ncbi.nlm.nih.gov/) was searched for articles relevant to the topic published till November 2023. The search was made using keywords such as Diabetic Retinopathy, inflammation, tear, biomarker, proteomics etc. The studies providing relevant information to prove the importance of biomarker discovery were chosen. After compiling the data, the manuscript writing was planned under relevant headings and sub-headings. RESULTS The review provides a comprehensive overview of all the tear protein biomarker studies in the field of DR and DME. Briefly, their potential in other diseases is also elucidated. While there are many studies pertaining to DR biomarkers, the identified markers lack validations which has restricted their usage in clinics. In case of DME, there was no such study towards biomarker discovery for its diagnosis and prognosis. CONCLUSIONS The review highlights major studies and their lacunae in the field of biomarkers discovery for DR and DME.
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Affiliation(s)
- Sarmeela Sharma
- Brien Holden Eye Research Centre, L V Prasad Eye Institute, Hyderabad, India
- Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Akash Belenje
- Anant Bajaj Retina Institute, LV Prasad Eye Institue, Hyderabad, India
| | - Brijesh Takkar
- Anant Bajaj Retina Institute, LV Prasad Eye Institue, Hyderabad, India
| | - Ritesh Narula
- Anant Bajaj Retina Institute, LV Prasad Eye Institue, Hyderabad, India
| | | | - Mudit Tyagi
- Anant Bajaj Retina Institute, LV Prasad Eye Institue, Hyderabad, India
| | | | - Raja Narayanan
- Anant Bajaj Retina Institute, LV Prasad Eye Institue, Hyderabad, India
| | - Inderjeet Kaur
- Brien Holden Eye Research Centre, L V Prasad Eye Institute, Hyderabad, India
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4
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Wang Z, Lin W, Luo C, Xue H, Wang T, Hu J, Huang Z, Fu D. Early diagnosis of thyroid-associated ophthalmopathy using label-free Raman spectroscopy and multivariate analysis. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2024; 310:123905. [PMID: 38266604 DOI: 10.1016/j.saa.2024.123905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2023] [Revised: 12/26/2023] [Accepted: 01/15/2024] [Indexed: 01/26/2024]
Abstract
Thyroid-associated ophthalmopathy (TAO) is the most common orbital disease in adults, with complex clinical manifestations and significant impacts on the life quality of patients. The current diagnosis of TAO lacks reliable biomarkers for early and non-invasive screening and detection, easily leading to poor prognosis. Therefore, it is essential to explore new methods for accurately predicting TAO development in its early stage. In this study, Raman spectroscopy, with non-destructive, label-free, and high-sensitivity characteristics, was used to analyze the differences in biochemical components of orbital adipocyte and tear samples between TAO and control groups. Furthermore, a multivariate analysis method (i.e., Principal Component Analysis-Linear Discriminant Analysis (PCA-LDA)) was applied for data processing and analysis. Compared with controls, PCA-LDA yielded TAO diagnostic accuracies of 72.7% and 75.0% using orbital adipocytes and tears, respectively. Our proof-of-concept results suggest that Raman spectroscopy holds potential for exploring the underlying pathogenesis of TAO, and its potential application in early screening of other thyroid-associated diseases can be further expanded.
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Affiliation(s)
- Zhihong Wang
- Department of Ophthalmology, Fujian Medical University Union Hospital, Fuzhou 350001, China
| | - Weiming Lin
- Key Laboratory of Opto-Electronic Science and Technology for Medicine of Ministry of Education, Fujian Provincial Key Laboratory for Photonics Technology, Fujian Normal University, Fuzhou 350117, China
| | - Chenyu Luo
- Department of Ophthalmology, Fujian Medical University Union Hospital, Fuzhou 350001, China
| | - Honghua Xue
- Department of Ophthalmology, Fujian Medical University Union Hospital, Fuzhou 350001, China
| | - Tingyin Wang
- Key Laboratory of Opto-Electronic Science and Technology for Medicine of Ministry of Education, Fujian Provincial Key Laboratory for Photonics Technology, Fujian Normal University, Fuzhou 350117, China
| | - Jianzhang Hu
- Department of Ophthalmology, Fujian Medical University Union Hospital, Fuzhou 350001, China
| | - Zufang Huang
- Key Laboratory of Opto-Electronic Science and Technology for Medicine of Ministry of Education, Fujian Provincial Key Laboratory for Photonics Technology, Fujian Normal University, Fuzhou 350117, China.
| | - Desheng Fu
- Department of Ophthalmology, Fujian Medical University Union Hospital, Fuzhou 350001, China.
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5
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Shiju TM, Yuan A. Extracellular vesicle biomarkers in ocular fluids associated with ophthalmic diseases. Exp Eye Res 2024; 241:109831. [PMID: 38401855 DOI: 10.1016/j.exer.2024.109831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Revised: 02/06/2024] [Accepted: 02/13/2024] [Indexed: 02/26/2024]
Abstract
Extracellular vesicles (EVs) are released as highly stable lipid bilayer particles carrying proteins, lipids, glycans and miRNAs. The contents of EVs vary based on the cellular origin, biogenesis route and the functional state of the cell suggesting certain diseased conditions. A growing body of evidence show that EVs carry important molecules implicated in the development and progression of ophthalmic diseases. EVs associated with ophthalmic diseases are mainly carried by one of the three ocular biofluids which include tears, aqueous humor and vitreous humor. This review summarizes the list of EV derived biomarkers identified thus far in ocular fluids for ophthalmic disease diagnosis. Further, the methods used for sample collection, sample volume and the sample numbers used in these studies have been highlighted. Emphasis has been given to describe the EV isolation and the characterization methods used, EV size profiled and the EV concentrations analyzed by these studies, thus providing a roadmap for future EV biomarker studies in ocular fluids.
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Affiliation(s)
| | - Alex Yuan
- Cole Eye Institute, Cleveland Clinic, Cleveland, OH, USA.
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Gupta N, Somayajulu M, Gurdziel K, LoGrasso G, Aziz H, Rosati R, McClellan S, Pitchaikannu A, Santra M, Shukkur MFA, Stemmer P, Hazlett LD, Xu S. The miR-183/96/182 cluster regulates sensory innervation, resident myeloid cells and functions of the cornea through cell type-specific target genes. Sci Rep 2024; 14:7676. [PMID: 38561433 PMCID: PMC10985120 DOI: 10.1038/s41598-024-58403-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Accepted: 03/28/2024] [Indexed: 04/04/2024] Open
Abstract
The conserved miR-183/96/182 cluster (miR-183C) is expressed in both corneal resident myeloid cells (CRMCs) and sensory nerves (CSN) and modulates corneal immune/inflammatory responses. To uncover cell type-specific roles of miR-183C in CRMC and CSN and their contributions to corneal physiology, myeloid-specific miR-183C conditional knockout (MS-CKO), and sensory nerve-specific CKO (SNS-CKO) mice were produced and characterized in comparison to the conventional miR-183C KO. Immunofluorescence and confocal microscopy of flatmount corneas, corneal sensitivity, and tear volume assays were performed in young adult naïve mice; 3' RNA sequencing (Seq) and proteomics in the trigeminal ganglion (TG), cornea and CRMCs. Our results showed that, similar to conventional KO mice, the numbers of CRMCs were increased in both MS-CKO and SNS-CKO vs age- and sex-matched WT control littermates, suggesting intrinsic and extrinsic regulations of miR-183C on CRMCs. The number of CRMCs was increased in male vs female MS-CKO mice, suggesting sex-dependent regulation of miR-183C on CRMCs. In the miR-183C KO and SNS-CKO, but not the MS-CKO mice, CSN density was decreased in the epithelial layer of the cornea, but not the stromal layer. Functionally, corneal sensitivity and basal tear volume were reduced in the KO and SNS-CKO, but not the MS-CKO mice. Tear volume in males is consistently higher than female WT mice. Bioinformatic analyses of the transcriptomes revealed a series of cell-type specific target genes of miR-183C in TG sensory neurons and CRMCs. Our data elucidate that miR-183C imposes intrinsic and extrinsic regulation on the establishment and function of CSN and CRMCs by cell-specific target genes. miR-183C modulates corneal sensitivity and tear production through its regulation of corneal sensory innervation.
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Affiliation(s)
- Naman Gupta
- Department of Ophthalmology, Visual and Anatomical Sciences, School of Medicine, Wayne State University, 540 E Canfield Street, Detroit, MI, 48201, USA
| | - Mallika Somayajulu
- Department of Ophthalmology, Visual and Anatomical Sciences, School of Medicine, Wayne State University, 540 E Canfield Street, Detroit, MI, 48201, USA
| | | | - Giovanni LoGrasso
- Department of Ophthalmology, Visual and Anatomical Sciences, School of Medicine, Wayne State University, 540 E Canfield Street, Detroit, MI, 48201, USA
| | - Haidy Aziz
- School of Biological Sciences, Wayne State University, Detroit, MI, USA
| | - Rita Rosati
- Institute of Environmental Health Sciences, Wayne State University, Detroit, MI, USA
| | - Sharon McClellan
- Department of Ophthalmology, Visual and Anatomical Sciences, School of Medicine, Wayne State University, 540 E Canfield Street, Detroit, MI, 48201, USA
| | - Ahalya Pitchaikannu
- Department of Ophthalmology, Visual and Anatomical Sciences, School of Medicine, Wayne State University, 540 E Canfield Street, Detroit, MI, 48201, USA
| | - Manoranjan Santra
- Department of Ophthalmology, Visual and Anatomical Sciences, School of Medicine, Wayne State University, 540 E Canfield Street, Detroit, MI, 48201, USA
| | - Muhammed Farooq Abdul Shukkur
- Department of Ophthalmology, Visual and Anatomical Sciences, School of Medicine, Wayne State University, 540 E Canfield Street, Detroit, MI, 48201, USA
| | - Paul Stemmer
- Institute of Environmental Health Sciences, Wayne State University, Detroit, MI, USA
| | - Linda D Hazlett
- Department of Ophthalmology, Visual and Anatomical Sciences, School of Medicine, Wayne State University, 540 E Canfield Street, Detroit, MI, 48201, USA
| | - Shunbin Xu
- Department of Ophthalmology, Visual and Anatomical Sciences, School of Medicine, Wayne State University, 540 E Canfield Street, Detroit, MI, 48201, USA.
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7
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Hashemi H, Ahmadi H, Rostami Z, Alishahi A, Heidari Z. The role of endothelial growth factor and tear levels in diabetic retinopathy in type 2 diabetes. Int Ophthalmol 2024; 44:143. [PMID: 38498296 DOI: 10.1007/s10792-024-03064-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Accepted: 02/16/2024] [Indexed: 03/20/2024]
Abstract
PURPOSE To evaluate the tear level of VEGF and the quantity of tear film in type 2 diabetic patients. METHODS Thirty patients with diabetic retinopathy (DR group) and 30 patients with no DR (NDR group), and 30 healthy subjects with age and gender matching were enrolled in this prospective comparative study. The tear samples were collected using the Schirmer strips, and the amount of moisture absorbed by the strips was used to determine the quantitative level of the tear film. The concentration of VEGF in the tear samples was measured using the enzyme-linked immunosorbent assay method. The variables were compared with an independent t-test and covariance analysis. RESULTS Mean tear level of VEGF was significantly higher in DR group (235.42 pg/ml) compared to NDR (75.11 pg/ml) and control (58.77 pg/ml) groups (P ≤ 0.001). There was no significant difference in the mean of VEGF between NDR and control patients (P = 1.00). Mean quantitative tear film levels were 7.15%, 9.72%, and 15.11% in DR, NDR, and healthy subjects, respectively (P < 0.05). The pairwise analysis showed significant differences in the level of VEGF between DR and both NDR (P = 0.001) and normal (P = 0.017) groups. However, there was no significant difference observed between NDR and normal eyes (P = 0.743). CONCLUSION The VEGF level in tear was higher in diabetic patients with DR, independent of tear volume. The tear VEGF measurement can be used as a valuable predictor to prevent DR in diabetic patients.
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Affiliation(s)
- Hassan Hashemi
- Noor Ophthalmology Research Center, Noor Eye Hospital, Tehran, Iran
| | - Hanieh Ahmadi
- Department of Ophthalmology, Faculty of Medicine, Bu-Ali Sina Hospital, Mazandaran University of Medical Sciences, Sari, Iran
| | - Zahra Rostami
- Department of Ophthalmology, Faculty of Medicine, Bu-Ali Sina Hospital, Mazandaran University of Medical Sciences, Sari, Iran
| | - Abbas Alishahi
- Department of Ophthalmology, Faculty of Medicine, Bu-Ali Sina Hospital, Mazandaran University of Medical Sciences, Sari, Iran
- Universal Scientific Education and Research Network (USERN), Tehran, Iran
| | - Zahra Heidari
- Department of Ophthalmology, Faculty of Medicine, Bu-Ali Sina Hospital, Mazandaran University of Medical Sciences, Sari, Iran.
- Psychiatry and Behavioral Sciences Research Center, Mazandaran University of Medical Sciences, Sari, Iran.
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8
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Wolf J, Franco JA, Yip R, Dabaja MZ, Velez G, Liu F, Bassuk AG, Mruthyunjaya P, Dufour A, Mahajan VB. Liquid Biopsy Proteomics in Ophthalmology. J Proteome Res 2024; 23:511-522. [PMID: 38171013 PMCID: PMC10845144 DOI: 10.1021/acs.jproteome.3c00756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2023] [Revised: 12/08/2023] [Accepted: 12/11/2023] [Indexed: 01/05/2024]
Abstract
Minimally invasive liquid biopsies from the eye capture locally enriched fluids that contain thousands of proteins from highly specialized ocular cell types, presenting a promising alternative to solid tissue biopsies. The advantages of liquid biopsies include sampling the eye without causing irreversible functional damage, potentially better reflecting tissue heterogeneity, collecting samples in an outpatient setting, monitoring therapeutic response with sequential sampling, and even allowing examination of disease mechanisms at the cell level in living humans, an approach that we refer to as TEMPO (Tracing Expression of Multiple Protein Origins). Liquid biopsy proteomics has the potential to transform molecular diagnostics and prognostics and to assess disease mechanisms and personalized therapeutic strategies in individual patients. This review addresses opportunities, challenges, and future directions of high-resolution liquid biopsy proteomics in ophthalmology, with particular emphasis on the large-scale collection of high-quality samples, cutting edge proteomics technology, and artificial intelligence-supported data analysis.
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Affiliation(s)
- Julian Wolf
- Molecular
Surgery Laboratory, Stanford University, Palo Alto, California 94305, United States
- Department
of Ophthalmology, Byers Eye Institute, Stanford
University, Palo Alto, California 94303, United States
| | - Joel A. Franco
- Molecular
Surgery Laboratory, Stanford University, Palo Alto, California 94305, United States
- Department
of Ophthalmology, Byers Eye Institute, Stanford
University, Palo Alto, California 94303, United States
| | - Rui Yip
- Molecular
Surgery Laboratory, Stanford University, Palo Alto, California 94305, United States
- Department
of Ophthalmology, Byers Eye Institute, Stanford
University, Palo Alto, California 94303, United States
| | - Mohamed Ziad Dabaja
- Departments
of Physiology and Pharmacology & Biochemistry and Molecular Biology,
Cumming School of Medicine, University of
Calgary, Calgary, Alberta T2N 4N1, Canada
| | - Gabriel Velez
- Molecular
Surgery Laboratory, Stanford University, Palo Alto, California 94305, United States
- Department
of Ophthalmology, Byers Eye Institute, Stanford
University, Palo Alto, California 94303, United States
| | - Fei Liu
- Department
of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts 02115, United States
| | - Alexander G. Bassuk
- Department
of Pediatrics, University of Iowa, Iowa City, Iowa 52242, United States
| | - Prithvi Mruthyunjaya
- Department
of Ophthalmology, Byers Eye Institute, Stanford
University, Palo Alto, California 94303, United States
| | - Antoine Dufour
- Departments
of Physiology and Pharmacology & Biochemistry and Molecular Biology,
Cumming School of Medicine, University of
Calgary, Calgary, Alberta T2N 4N1, Canada
| | - Vinit B. Mahajan
- Molecular
Surgery Laboratory, Stanford University, Palo Alto, California 94305, United States
- Department
of Ophthalmology, Byers Eye Institute, Stanford
University, Palo Alto, California 94303, United States
- Veterans
Affairs Palo Alto Health Care System, Palo Alto, California 94304, United States
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Akkurt Arslan M, Rabut G, Chardonnet S, Pionneau C, Kobal A, Gratas Pelletier M, Harfouche N, Réaux La Goazigo A, Baudouin C, Brignole-Baudouin F, Kessal K. Expanded biochemical analyses of human tear fluid: Polyvalent faces of the schirmer strip. Exp Eye Res 2023; 237:109679. [PMID: 37858607 DOI: 10.1016/j.exer.2023.109679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2023] [Revised: 09/27/2023] [Accepted: 10/16/2023] [Indexed: 10/21/2023]
Abstract
The tear film forms a protective barrier between the ocular surface and the external environment. Despite its small volume, recent advancements in preanalytical and analytical procedures have enabled its in-depth analysis using multiple approaches. However, the diversity of tear film collection methods and the lack of standardization in pre-analytical methods represent the main obstacles to reproducible results and comparison among different studies. In this study, we first improved the pre-analytical procedures for the extraction of various molecular entities from Schirmer strips (ScS). Subsequently, our investigation focused on analyzing the molecular variances that might occur between two primary tear collection methods: capillary tube (CT) and ScS. Additionally, we examined different parts of the ScS to underscore these variations, which could serve as crucial factors for developing a standardized, optimized protocol for sample processing. Our results show that the inclusion of surfactants in the extraction process enhanced both the yield of protein extraction and the number of proteins identified in ScS, by effectively lysing the cells and improving the solubility of several intracellular proteins. In addition to proteins, nucleic acids could also be recovered for gene expression analyses, particularly from the bulb region of the ScS which is placed in the cul-de-sac. Despite their diluted nature, extracts from ScS remain a suitable material for retrieving tear proteins such as IL-17A at levels as low as the fg/mL range, thanks to highly sensitive immunoassays. Collection methods can affect measured tear protein levels. Lactoferrin is found in higher percentages in capillary electrophoresis analysis of tears collected using ScS compared to tears collected by CT (39.6 ± 4.8% versus 31 ± 4.4%).
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Affiliation(s)
- Murat Akkurt Arslan
- Institut National de La Santé et de La Recherche Médicale INSERM UMRS 968, CNRS, UMR 7210, Institut de La Vision, IHU ForeSight, Sorbonne Université UM80, 75012, Paris, France.
| | - Ghislaine Rabut
- Hôpital National de La Vision des 15-20, Service 3, 75012, Paris, France.
| | - Solenne Chardonnet
- Sorbonne Université, INSERM, UMS Production et Analyse des Données en Sciences de La Vie et en Santé, PASS, Plateforme Post-génomique de La Pitié-Salpêtrière, P3S, 75013, Paris, France.
| | - Cédric Pionneau
- Sorbonne Université, INSERM, UMS Production et Analyse des Données en Sciences de La Vie et en Santé, PASS, Plateforme Post-génomique de La Pitié-Salpêtrière, P3S, 75013, Paris, France.
| | - Alfred Kobal
- Hôpital National de La Vision des 15-20, Laboratoire d'Ophtalmobiologie, 75012, Paris, France.
| | | | - Nouara Harfouche
- Hôpital National de La Vision des 15-20, Laboratoire d'Ophtalmobiologie, 75012, Paris, France.
| | - Annabelle Réaux La Goazigo
- Institut National de La Santé et de La Recherche Médicale INSERM UMRS 968, CNRS, UMR 7210, Institut de La Vision, IHU ForeSight, Sorbonne Université UM80, 75012, Paris, France.
| | - Christophe Baudouin
- Institut National de La Santé et de La Recherche Médicale INSERM UMRS 968, CNRS, UMR 7210, Institut de La Vision, IHU ForeSight, Sorbonne Université UM80, 75012, Paris, France; Hôpital National de La Vision des 15-20, Service 3, 75012, Paris, France; Hôpital National de La Vision des 15-20, INSERM-DGOS CIC 1423, IHU FOReSIGHT, 75012, Paris, France; Hôpital Ambroise Paré, Assistance Publique-Hôpitaux de Paris APHP, Service d'Ophtalmologie, Université Versailles Saint-Quentin-en-Yvelines, Paris Saclay, 92100, Boulogne, France.
| | - Françoise Brignole-Baudouin
- Institut National de La Santé et de La Recherche Médicale INSERM UMRS 968, CNRS, UMR 7210, Institut de La Vision, IHU ForeSight, Sorbonne Université UM80, 75012, Paris, France; Hôpital National de La Vision des 15-20, Laboratoire d'Ophtalmobiologie, 75012, Paris, France; Hôpital National de La Vision des 15-20, INSERM-DGOS CIC 1423, IHU FOReSIGHT, 75012, Paris, France; Faculté de Pharmacie de Paris, Université Paris Cité, 75006 Paris, France.
| | - Karima Kessal
- Institut National de La Santé et de La Recherche Médicale INSERM UMRS 968, CNRS, UMR 7210, Institut de La Vision, IHU ForeSight, Sorbonne Université UM80, 75012, Paris, France; Hôpital National de La Vision des 15-20, Laboratoire d'Ophtalmobiologie, 75012, Paris, France; Hôpital National de La Vision des 15-20, INSERM-DGOS CIC 1423, IHU FOReSIGHT, 75012, Paris, France.
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Tham ML, Mahmud A, Abdullah M, Md Saleh R, Mohammad Razali A, Cheah YK, Mohd Taib N, Ho KL, Mahmud M, Mohd Isa M. Tear Samples for Protein Extraction: Comparative Analysis of Schirmer's Test Strip and Microcapillary Tube Methods. Cureus 2023; 15:e50972. [PMID: 38259376 PMCID: PMC10800704 DOI: 10.7759/cureus.50972] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/21/2023] [Indexed: 01/24/2024] Open
Abstract
INTRODUCTION Tear sampling is an attractive option for collecting biological samples in ophthalmology clinics, as it offers a non-invasive alternative to other invasive techniques. However, there are many tear sampling methods still in consideration. This study explores the suitability of Schirmer's test strip and microcapillary tube as reliable and satisfactory methods for tear sampling. METHODS Tear samples were collected from eight healthy volunteers using the standard Schirmer's test strip method with or without anesthesia and microcapillary tubes. The total tear protein concentrations were analyzed via spectrophotometry and bicinchoninic acid (BCA) protein assay. The protein profile was determined by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). The optimal wetting length of Schirmer's strip and suitable buffer solutions were compared. Discomfort levels reported by participants and the ease of execution for ophthalmologists were also evaluated. RESULTS Tear samples exhibited typical protein profiles as shown by SDS-PAGE. The mean total protein obtained from an optimum wetting length of 20 mm using Schirmer's strip without anesthesia in phosphate-buffered saline (PBS) yielded substantial quantities of protein as measured by nanophotometer (220.20 ± 67.43 µg) and the BCA protein assay (210.34 ± 59.46 µg). This method collected a significantly higher quantity of protein compared to the microcapillary tube method (p=0.004) which was much more difficult to standardize. The clinician found it harder to utilize microcapillary tubes, while participants experienced higher insecurity and less discomfort with the microcapillary tube method. PBS used during the tear protein extraction process eluted higher tear protein concentration than ammonium bicarbonate, although the difference was not statistically significant. Using anaesthesia did not ease the sampling procedure substantially and protein quantity was maintained. CONCLUSION Good quality and quantity of protein from tear samples were extracted with the optimized procedure. Schirmer's strip test in the absence of local anesthesia provided a standard, convenient, and non-invasive method for tear collection.
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Affiliation(s)
- May Ling Tham
- Department of Ophthalmology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, MYS
| | - Aidalina Mahmud
- Department of Community Health, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, MYS
| | - Maha Abdullah
- Department of Pathology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, MYS
| | - Rafidah Md Saleh
- Department of Ophthalmology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, MYS
| | - Amirah Mohammad Razali
- Department of Ophthalmology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, MYS
| | - Yoke Kqueen Cheah
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, MYS
| | - Niazlin Mohd Taib
- Department of Medical Microbiology and Parasitology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, MYS
| | - Kok Lian Ho
- Department of Pathology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, MYS
| | - Mazaya Mahmud
- Department of Ophthalmology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, MYS
| | - Muhammad Mohd Isa
- Department of Ophthalmology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, MYS
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11
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Diaz PM, Leehans A, Ravishankar P, Daily A. Multiomic Approaches for Cancer Biomarker Discovery in Liquid Biopsies: Advances and Challenges. Biomark Insights 2023; 18:11772719231204508. [PMID: 37846373 PMCID: PMC10576933 DOI: 10.1177/11772719231204508] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Accepted: 09/12/2023] [Indexed: 10/18/2023] Open
Abstract
Cancer is a complex and heterogeneous disease that poses a significant threat to global health. Early diagnosis and treatment are critical for improving patient outcomes, and the use of liquid biopsies has emerged as a promising approach for cancer detection and monitoring. Traditionally, cancer diagnosis has relied on invasive tissue biopsies, the collection of which can prove challenging for patients and the results of which may not always provide accurate results due to tumor heterogeneity. Liquid biopsies have gained increasing attention as they provide a non-invasive and accessible source of cancer biomarkers, which can be used to diagnose cancer, monitor treatment response, and detect relapse. The integration of -omics technologies, such as proteomics, genomics, and metabolomics, has further enhanced the capabilities of liquid biopsies by introducing precision oncology and enabling the tailoring of treatment for individual patients based on their unique tumor biology. In this review, we will discuss the challenges and advances in the field of cancer liquid biopsies and the integration of -omics technologies for different types of liquid biopsies, including blood, tear, urine, sweat, saliva, and cerebrospinal fluid.
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Affiliation(s)
- Paola Monterroso Diaz
- Namida Lab Inc., Fayetteville, AR, USA
- University of Arkansas, Department of Biomedical Engineering, Fayetteville, AR, USA
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12
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Tyulina VV, Senin II. Method for Collection of Tear Fluid for Evaluation Its Antioxidant Properties. Bull Exp Biol Med 2023; 175:492-496. [PMID: 37768462 DOI: 10.1007/s10517-023-05893-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Indexed: 09/29/2023]
Abstract
A technique of collection of the tear fluid with Schirmer strips for evaluation of the activity of the main antioxidant defense enzymes (superoxide dismutase, catalase, and glutathione peroxidase) in the tear fluid was proposed. The degree of extraction of the studied enzymes from the Schirmer strip is >85%. Cytometry showed that conjunctival and corneal cells can be transferred to the Schirmer strips during tear collection, which leads to sample contamination with intracellular fractions of the antioxidant enzymes. The approach proposed by us allows avoiding this contamination during tear fluid sampling. This technique makes it possible to increase the accuracy of determining the activity of antioxidant protection enzymes in the tear fluid and can be used for diagnostics of ocular surface pathologies in clinical practice.
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Affiliation(s)
- V V Tyulina
- A. N. Belozersky Institute of Physico-Chemical Biology, M. V. Lo-monosov Moscow State University, Moscow, Russia
| | - I I Senin
- A. N. Belozersky Institute of Physico-Chemical Biology, M. V. Lo-monosov Moscow State University, Moscow, Russia.
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13
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Hefley BS, Deighan C, Vasini B, Khan A, Hjortdal J, Riaz KM, Liu Y, Karamichos D. Revealing the presence of tear extracellular vesicles in Keratoconus. Exp Eye Res 2022; 224:109242. [PMID: 36084727 PMCID: PMC10159047 DOI: 10.1016/j.exer.2022.109242] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Revised: 08/22/2022] [Accepted: 08/30/2022] [Indexed: 11/19/2022]
Abstract
Extracellular vesicles (EVs) are lipid-bound vesicles that originate from the endosomal system or budded off from the plasma membrane. EVs are involved in cell-cell communication via transporting DNA, RNA, and proteins from one cell to another. Tear EVs (tEVs) have been reported in dry eye, Sjӧgren's Syndrome, and primary open-angle glaucoma. In this study, we sought to investigate the presence of tEVs in relation to keratoconus (KC). Tears were passively collected from the lateral meniscus from 10 healthy (5 males and 5 females) and 9 KC (4 males and 5 females) subjects. Tear samples were processed and analyzed using the ExoView™ R100. Statistical analysis was performed using a Mann-Whitney U non-parametric Student's t-test. All tEVs, in both Healthy and KC subjects, showed a CD9+ dominant tEV cohort independent of sex. A significant decrease in CD63+/CD9+ and CD63+/CD81+/CD9+ was found in the male KC tEVs (p < 0.05), but not in females compared to their healthy counterparts. Neither Healthy nor KC tEVs showed differences in the total number of tEVs, however significant differences were identified between the sexes (p < 0.05), with males having a higher number of tEVs. tEVs diameters ranged from 50 to 200 nm, in both Healthy and KC cohorts, with the majority in the 50-80 nm range suggesting exosome-dominant cohorts. To our knowledge, this is the first time, to date, that tEVs have been isolated and characterized in KCs. While further studies are warranted, the tEVs differences between KC and Healthy subjects suggest a potential role for tEVs in KC pathogenesis.
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Affiliation(s)
- Brenna S Hefley
- North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, TX, 76107, USA; Department of Pharmaceutical Sciences, College of Pharmacy, University of North Texas Health Science Center, Fort Worth, TX, 76107, USA
| | | | - Brenda Vasini
- North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, TX, 76107, USA; Department of Pharmaceutical Sciences, College of Pharmacy, University of North Texas Health Science Center, Fort Worth, TX, 76107, USA
| | - Asher Khan
- Department of Ophthalmology, Dean McGee Eye Institute, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Jesper Hjortdal
- Department of Ophthalmology, Aarhus University Hospital, Palle Juul-Jensens Boulevard 167, 8200, Aarhus N, Denmark
| | - Kamran M Riaz
- Department of Ophthalmology, Dean McGee Eye Institute, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Yutao Liu
- Department of Cellular Biology and Anatomy, Augusta University, Augusta, GA, USA; James & Jean Culver Vision Discovery Institute, Augusta University, Augusta, GA, USA; Center for Biotechnology and Genomic Medicine, Augusta University, Augusta, GA, USA
| | - Dimitrios Karamichos
- North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, TX, 76107, USA; Department of Pharmaceutical Sciences, College of Pharmacy, University of North Texas Health Science Center, Fort Worth, TX, 76107, USA; Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, 3500 Camp Bowie Blvd, Fort Worth, TX, 76107, USA.
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14
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Ozdalgic B, Gul M, Uygun ZO, Atçeken N, Tasoglu S. Emerging Applications of Electrochemical Impedance Spectroscopy in Tear Film Analysis. BIOSENSORS 2022; 12:827. [PMID: 36290964 PMCID: PMC9599721 DOI: 10.3390/bios12100827] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 09/20/2022] [Accepted: 09/24/2022] [Indexed: 06/16/2023]
Abstract
Human tear film, with a flow rate of 1-3 µL/min, is a rich bodily fluid that transmits a variety of metabolites and hormones containing proteins, lipids and electrolytes that provide clues about ocular and systemic diseases. Analysis of disease biomarkers such as proteins, mRNA, enzymes and cytokines in the tear film, collected by noninvasive methods, can provide significant results for sustaining a predictive, preventive and personalized medicine regarding various diseases such as glaucoma, diabetic retinopathy, keratoconus, dry eye, cancer, Alzheimer's disease, Parkinson's disease and COVID-19. Electrochemical impedance spectroscopy (EIS) offers a powerful technique for analyzing these biomarkers. EIS detects electrical equivalent circuit parameters related to biorecognition of receptor-analyte interactions on the electrode surface. This method is advantageous as it performs a label-free detection and allows the detection of non-electroactive compounds that cannot be detected by direct electron transfer, such as hormones and some proteins. Here, we review the opportunities regarding the integration of EIS into tear fluid sampling approaches.
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Affiliation(s)
- Berin Ozdalgic
- Department of Mechanical Engineering, Engineering Faculty, Koç University, Istanbul 34450, Türkiye
- Koç University Translational Medicine Research Center (KUTTAM), Koç University, Istanbul 34450, Türkiye
- Division of Optometry, School of Med Services & Techniques, Dogus University, Istanbul 34775, Türkiye
| | - Munire Gul
- Koç University Translational Medicine Research Center (KUTTAM), Koç University, Istanbul 34450, Türkiye
| | - Zihni Onur Uygun
- Department of Mechanical Engineering, Engineering Faculty, Koç University, Istanbul 34450, Türkiye
- Koç University Translational Medicine Research Center (KUTTAM), Koç University, Istanbul 34450, Türkiye
- Department of Biochemistry, Faculty of Medicine, Kafkas University, Kars 36100, Türkiye
| | - Nazente Atçeken
- Koç University Translational Medicine Research Center (KUTTAM), Koç University, Istanbul 34450, Türkiye
| | - Savas Tasoglu
- Department of Mechanical Engineering, Engineering Faculty, Koç University, Istanbul 34450, Türkiye
- Koç University Translational Medicine Research Center (KUTTAM), Koç University, Istanbul 34450, Türkiye
- Boğaziçi Institute of Biomedical Engineering, Boğaziçi University, Istanbul 34684, Türkiye
- Koç University Arçelik Research Center for Creative Industries (KUAR), Koç University, Istanbul 34450, Türkiye
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15
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An Extensive Study of Phenol Red Thread as a Novel Non-Invasive Tear Sampling Technique for Proteomics Studies: Comparison with Two Commonly Used Methods. Int J Mol Sci 2022; 23:ijms23158647. [PMID: 35955782 PMCID: PMC9369290 DOI: 10.3390/ijms23158647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Revised: 07/22/2022] [Accepted: 07/30/2022] [Indexed: 02/04/2023] Open
Abstract
Tear samples are considered in recent publications as easily, noninvasively collectible information sources for precision medicine. Their complex composition may aid the identification of biomarkers and the monitoring of the effectiveness of treatments for the eye and systemic diseases. Sample collection and processing are key steps in any analytical method, especially if subtle personal differences need to be detected. In this work, we evaluate the usability of a novel sample collection technique for human tear samples using phenol red threads (cotton thread treated with the pH indicator phenol red), which are efficiently used to measure tear volume in clinical diagnosis. The low invasiveness and low discomfort to the patients have already been demonstrated, but their applicability for proteomic sample collection has not yet been compared to other methods. We have shown, using various statistical approaches, the qualitative and quantitative differences in proteomic samples collected with this novel and two traditional methods using either glass capillaries or Schirmer’s paper strips. In all parameters studied, the phenol red threads proved to be equally or even more suitable than traditional methods. Based on detectability using different sampling methods, we have classified proteins in tear samples.
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16
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de Barros MRM, Chakravarti S. Pathogenesis of keratoconus: NRF2-antioxidant, extracellular matrix and cellular dysfunctions. Exp Eye Res 2022; 219:109062. [PMID: 35385756 DOI: 10.1016/j.exer.2022.109062] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 03/19/2022] [Accepted: 03/30/2022] [Indexed: 11/04/2022]
Abstract
Keratoconus (KC) is a degenerative disease associated with cell and extracellular matrix (ECM) loss that causes gradual thinning and steepening of the cornea and loss of vision. Collagen cross linking with ultraviolet light treatment can strengthen the ECM and delay weakening of the cornea, but severe cases require corneal transplantation. KC is multifactorial and multigenic, but its pathophysiology is still an enigma. Multiple approaches are being pursued to elucidate the molecular changes that underlie the corneal phenotype to identify relevant genes for tailored candidate searches and to develop potential biomarkers and targets for therapeutic interventions. Recent proteomic and transcriptomic studies suggest dysregulations in oxidative stress, NRF2-regulated antioxidant programs, WNT-signaling, TGF-β, ECM and matrix metalloproteinases. This review aims to provide a broad update on the transcriptomic and proteomic studies of KC with a focus on findings that relate to oxidative stress, and dysregulations in cellular and extracellular matrix functions.
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Affiliation(s)
| | - Shukti Chakravarti
- Department of Ophthalmology, NYU Grossman School of Medicine, NY, 10016, USA; Department of Pathology, NYU Grossman School of Medicine, NY, 10016, USA.
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17
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Mudgil P. Antimicrobial Tear Lipids in the Ocular Surface Defense. Front Cell Infect Microbiol 2022; 12:866900. [PMID: 35433501 PMCID: PMC9008483 DOI: 10.3389/fcimb.2022.866900] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Accepted: 03/07/2022] [Indexed: 12/05/2022] Open
Abstract
The concept of antimicrobial lipids as effectors of innate host defense is an emerging field. There is limited knowledge on the antimicrobial role of lipids in the ocular environment. Tears act as first line of defense to protect the ocular surface from infections. Antimicrobial effects of tear lipids have been demonstrated using meibomian lipids that are the source of majority of lipids in tears. This article describes the knowledge available on the antimicrobial role of tear lipids at the ocular surface and the antimicrobial potential of various lipid classes present in tears that can contribute to antimicrobial protection of the eye. Like other mucosal secretions, tears contain many proteins and lipids with known antimicrobial effects. The antimicrobial defense of tears is far stronger than can be demonstrated by the effects of individual compounds many of which are present in low concentrations but synergistic and additive interactions between them provide substantial antimicrobial protection to the ocular surface. It is inferred that antimicrobial lipids play important role in innate defense of tears, and cooperative interactions between various antimicrobial lipids and proteins in tears provide a potent host defense mechanism that is effective against a broad spectrum of pathogens and renders self-sterilizing properties to tears for keeping the microbial load low at the ocular surface.
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18
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Evaluation of vascular endothelial growth factor (VEGF) level in the tears and serum of age-related macular degeneration patients. Sci Rep 2022; 12:4423. [PMID: 35292705 PMCID: PMC8924159 DOI: 10.1038/s41598-022-08492-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 03/08/2022] [Indexed: 11/09/2022] Open
Abstract
Age-related macular degeneration (AMD) is an important cause of irreversible central blindness worldwide. Clinical manifestations range from asymptomatic in early and intermediate AMD to significant vision loss in late AMD. Approximately 10% of cases of early AMD eventually progress to the late advanced stage, influenced by the upregulation of vascular endothelial growth factor (VEGF). In this study, we evaluated VEGF concentration in the tears and serum of AMD patients. Our study revealed a significantly higher level of VEGF in the tears of patients with AMD compared with controls. The tear VEGF level has high sensitivity and specificity, and is significantly related to the severity of AMD, whilst serum VEGF level is non-specific and non-predictive of AMD severity. Thus, VEGF level in the tears may be used as a non-invasive biomarker for AMD progression. A large cohort study is needed for further verification.
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Tears as the Next Diagnostic Biofluid: A Comparative Study between Ocular Fluid and Blood. APPLIED SCIENCES-BASEL 2022. [DOI: 10.3390/app12062884] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The need to easily isolate small molecular weight proteins and genomic fragments has prompted a search for an alternative biofluid to blood that has traversed sweat, urine, saliva, and even breath. In this study, both the genomic and proteomic profiles of tears and blood are evaluated to determine the similarity and differences between the two biofluids. Both fluids were tested utilizing microarray panels for identifying proteins as well as isolation of microRNA for sequencing. As anticipated, most (118) of the proteins detected in plasma were also detected in the tear samples, with tear samples also showing 34 unique proteins that were not found in the plasma. Over 400 microRNAs were isolated in both samples with 250 microRNA fragments commonly expressed in both tears and blood. This preliminary analysis, along with simplicity of collection and processing, lends credence to further investigate tears as an alternative biofluid to blood.
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Torné-Morató H, Donati P, Pompa PP. Nanoplasmonic Strip Test for Salivary Glucose Monitoring. NANOMATERIALS 2021; 12:nano12010105. [PMID: 35010055 PMCID: PMC8746375 DOI: 10.3390/nano12010105] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Revised: 12/23/2021] [Accepted: 12/27/2021] [Indexed: 12/19/2022]
Abstract
Nowadays, there is an increasing interest in Point-of-care (POC) devices for the noninvasive glucose assessment. Despite the recent progress in glucose self-monitoring, commercially available devices still use invasive samples such as blood or interstitial fluids, and they are not equipment-free and affordable for the whole population. Here, we report a fully integrated strip test for the semi-quantitative detection of glucose in whole saliva. The colorimetric mechanism consists of an enzyme-mediated reshaping of multibranched gold nanoparticles (MGNPs) into nanospheres with an associated plasmonic shift and consequent blue-to-red color change, clearly detectable in less than 10 min.
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Affiliation(s)
- Helena Torné-Morató
- Nanobiointeractions & Nanodiagnostics, Istituto Italiano di Tecnologia (IIT), via Morego, 30-16163 Genova, Italy; (H.T.-M.); (P.D.)
- Department of Chemistry and Industrial Chemistry, University of Genova, via Dodecaneso, 31-16146 Genova, Italy
| | - Paolo Donati
- Nanobiointeractions & Nanodiagnostics, Istituto Italiano di Tecnologia (IIT), via Morego, 30-16163 Genova, Italy; (H.T.-M.); (P.D.)
| | - Pier Paolo Pompa
- Nanobiointeractions & Nanodiagnostics, Istituto Italiano di Tecnologia (IIT), via Morego, 30-16163 Genova, Italy; (H.T.-M.); (P.D.)
- Correspondence:
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Proteomic Analysis of Tears and Conjunctival Cells Collected with Schirmer Strips Using timsTOF Pro: Preanalytical Considerations. Metabolites 2021; 12:metabo12010002. [PMID: 35050124 PMCID: PMC8778087 DOI: 10.3390/metabo12010002] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 12/16/2021] [Accepted: 12/17/2021] [Indexed: 12/24/2022] Open
Abstract
This study aimed to investigate the human proteome profile of samples collected from whole (W) Schirmer strips (ScS) and their two parts—the bulb (B) and the rest of the strip (R)—with a comprehensive proteomic approach using a trapped ion mobility mass spectrometer, the timsTOF Pro. Eight ScS were collected from two healthy subjects at four different visits to be separated into three batches, i.e., 4W, 4B, and 4R. In total, 1582 proteins were identified in the W, B, and R batches. Among all identified proteins, binding proteins (43.4%) and those with catalytic activity (42.2%) constituted more than 80% of the molecular functions. The most represented biological processes were cellular processes (31.2%), metabolic processes (20.8%), and biological regulation (13.1%). Enzymes were the most represented protein class (41%), consisting mainly of hydrolases (47.5%), oxidoreductases (22.1%), and transferases (16.7%). The bulb (B), which is in contact with the conjunctiva, might collect both tear and cell proteins and therefore promote the identification of more proteins. Processing B and R separately before mass spectrometry (MS) analysis, combined with the high data acquisition speed and the addition of ion-mobility-based separation in the timsTOF Pro, can bring a new dimension to biomarker investigations of a limited sample such as tear fluid.
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