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Petrillo F, Tortori A, Vallino V, Galdiero M, Fea AM, De Sanctis U, Reibaldi M. Understanding Acanthamoeba Keratitis: An In-Depth Review of a Sight-Threatening Eye Infection. Microorganisms 2024; 12:758. [PMID: 38674702 PMCID: PMC11052265 DOI: 10.3390/microorganisms12040758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2024] [Revised: 04/02/2024] [Accepted: 04/04/2024] [Indexed: 04/28/2024] Open
Abstract
Acanthamoeba keratitis (AK) is a rare but potentially sight-threatening corneal infection caused by the Acanthamoeba parasite. This microorganism is found ubiquitously in the environment, often in freshwater, soil, and other sources of moisture. Despite its low incidence, AK presents significant challenges due to delayed diagnosis and the complex nature of therapeutic management. Early recognition is crucial to prevent severe ocular complications, including corneal ulceration and vision loss. Diagnostic modalities and treatment strategies may vary greatly depending on the clinical manifestation and the available tools. With the growing reported cases of Acanthamoeba keratitis, it is essential for the ophthalmic community to thoroughly understand this condition for its effective management and improved outcomes. This review provides a comprehensive overview of AK, encompassing its epidemiology, risk factors, pathophysiology, clinical manifestations, diagnosis, and treatment.
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Affiliation(s)
- Francesco Petrillo
- Department of Surgical Sciences, University of Turin, 10126 Turin, Italy; (V.V.); (A.M.F.); (U.D.S.); (M.R.)
- Department of Ophthalmology, “City of Health and Science” Hospital, 10126 Turin, Italy
| | - Antonia Tortori
- Ophthalmology Unit, Surgery Department, Piacenza Hospital, 29121 Piacenza, Italy;
| | - Veronica Vallino
- Department of Surgical Sciences, University of Turin, 10126 Turin, Italy; (V.V.); (A.M.F.); (U.D.S.); (M.R.)
- Department of Ophthalmology, “City of Health and Science” Hospital, 10126 Turin, Italy
| | - Marilena Galdiero
- Department of Experimental Medicine, University of Campania “Luigi Vanvitelli”, 81100 Naples, Italy;
| | - Antonio M. Fea
- Department of Surgical Sciences, University of Turin, 10126 Turin, Italy; (V.V.); (A.M.F.); (U.D.S.); (M.R.)
- Department of Ophthalmology, “City of Health and Science” Hospital, 10126 Turin, Italy
| | - Ugo De Sanctis
- Department of Surgical Sciences, University of Turin, 10126 Turin, Italy; (V.V.); (A.M.F.); (U.D.S.); (M.R.)
- Department of Ophthalmology, “City of Health and Science” Hospital, 10126 Turin, Italy
| | - Michele Reibaldi
- Department of Surgical Sciences, University of Turin, 10126 Turin, Italy; (V.V.); (A.M.F.); (U.D.S.); (M.R.)
- Department of Ophthalmology, “City of Health and Science” Hospital, 10126 Turin, Italy
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Bahrami S, Avarseji AA, Zarei M, Haji Hajikolaei MR. First Report of Isolation and Characterization of Acanthamoeba spp. from the Milk Used for Calf Feeding. Acta Parasitol 2024; 69:609-615. [PMID: 38285086 DOI: 10.1007/s11686-024-00805-2] [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: 05/05/2023] [Accepted: 01/09/2024] [Indexed: 01/30/2024]
Abstract
PURPOSE Acanthamoeba spp. can be found in natural and artificial environments, which reflects their high adaptability to different conditions. Based on the available data, there is scarce information about the isolation of amoeba from milk. This study aimed to investigate the probable presence of Acanthamoeba in milk used for calf feeding. METHODS 200 milk samples from 50 industrial and traditional farms were collected. The samples were filtered and cultured on the 1.5% Non-nutrient agar medium. The amoebic growth was examined with an inverted microscope daily. DNA was extracted from the positive plates, and a PCR reaction was undertaken using the primers amplifying the Acanthamoeba 18 S rRNA gene. Five samples were purified and sequenced using specific primers. Maximum likelihood reconstructions were performed using the phylogenetic program MEGA software. The osmo and thermotolerance of isolated trophozoites were examined as well. RESULTS Out of 200 milk samples, Acanthamoeba was isolated from 27 (13.5%). The phylogenetic tree represents that all the isolates belonged to the genotype T4. Results of thermo and osmotolerance tests showed that isolates could develop at 37 and 43 ◦C. Besides, trophozoites survived at 0.5 M mannitol and 1 M. CONCLUSION For the first time, Acanthamoeba spp. were isolated from milk used to feed dairy calves. Due to Acanthamoeba's neglected role in pathogen persistence and survival, hygiene instructions should be reconsidered.
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Affiliation(s)
- Somayeh Bahrami
- Department of Parasitology, Faculty of Veterinary Medicine, Shahid Chamran University of Ahvaz, Ahvaz, Iran.
| | - Amir Ali Avarseji
- Department of Parasitology, Faculty of Veterinary Medicine, Shahid Chamran University of Ahvaz, Ahvaz, Iran
| | - Mehdi Zarei
- Department of Food Hygiene, Faculty of Veterinary Medicine, Shahid Chamran University of Ahvaz, Ahvaz, Iran
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Ilyas M, Stapleton F, Willcox MDP, Henriquez F, Peguda HK, Rayamajhee B, Zahid T, Petsoglou C, Carnt NA. Epidemiology of and Genetic Factors Associated with Acanthamoeba Keratitis. Pathogens 2024; 13:142. [PMID: 38392880 PMCID: PMC10892102 DOI: 10.3390/pathogens13020142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 01/14/2024] [Accepted: 01/31/2024] [Indexed: 02/25/2024] Open
Abstract
Acanthamoeba keratitis (AK) is a severe, rare protozoal infection of the cornea. Acanthamoeba can survive in diverse habitats and at extreme temperatures. AK is mostly seen in contact lens wearers whose lenses have become contaminated or who have a history of water exposure, and in those without contact lens wear who have experienced recent eye trauma involving contaminated soil or water. Infection usually results in severe eye pain, photophobia, inflammation, and corneal epithelial defects. The pathophysiology of this infection is multifactorial, including the production of cytotoxic proteases by Acanthamoeba that degrades the corneal epithelial basement membrane and induces the death of ocular surface cells, resulting in degradation of the collagen-rich corneal stroma. AK can be prevented by avoiding risk factors, which includes avoiding water contact, such as swimming or showering in contact lenses, and wearing protective goggles when working on the land. AK is mostly treated with an antimicrobial therapy of biguanides alone or in combination with diaminidines, although the commercial availability of these medicines is variable. Other than anti-amoeba therapies, targeting host immune pathways in Acanthamoeba disease may lead to the development of vaccines or antibody therapeutics which could transform the management of AK.
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Affiliation(s)
- Muhammad Ilyas
- Primary & Secondary Healthcare Department, Punjab 54000, Pakistan; (M.I.)
| | - Fiona Stapleton
- School of Optometry and Vision Science, University of NSW, Sydney, NSW 2052, Australia (H.K.P.)
| | - Mark D. P. Willcox
- School of Optometry and Vision Science, University of NSW, Sydney, NSW 2052, Australia (H.K.P.)
| | - Fiona Henriquez
- School of Health and Life Sciences, The University of the West of Scotland, Glasgow G72 0LH, UK
| | - Hari Kumar Peguda
- School of Optometry and Vision Science, University of NSW, Sydney, NSW 2052, Australia (H.K.P.)
| | - Binod Rayamajhee
- School of Optometry and Vision Science, University of NSW, Sydney, NSW 2052, Australia (H.K.P.)
| | - Tasbiha Zahid
- Primary & Secondary Healthcare Department, Punjab 54000, Pakistan; (M.I.)
| | | | - Nicole A. Carnt
- School of Optometry and Vision Science, University of NSW, Sydney, NSW 2052, Australia (H.K.P.)
- Centre for Vision Research, Westmead Institute for Medical Research, Sydney, NSW 2145, Australia
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Huang L, Suhler EB, Rosenberg C, Ta Kim D, Winthrop KL, Doan T, Lin P. Acanthamoeba-associated retinitis successfully treated with intravitreal and systemic antimicrobials. Am J Ophthalmol Case Rep 2023; 32:101902. [PMID: 37663996 PMCID: PMC10474359 DOI: 10.1016/j.ajoc.2023.101902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Revised: 07/03/2023] [Accepted: 07/19/2023] [Indexed: 09/05/2023] Open
Abstract
Purpose To describe a case of unilateral Acanthamoeba-associated retinitis in the absence of concomitant corneal infection in an immunocompetent host without risk factors. Observations A 37-year-old woman presented with unilateral multifocal retinitis with minimal vitritis. Anterior segment was normal. Conventional diagnostics of bacterial, fungal, viral, Toxoplasma and Toxocara etiologies all returned negative. Empiric treatments were unsuccessful, including oral valacyclovir, oral fluconazole, as well as intravitreal injection of vancomycin and ceftazidime. Metagenomic deep sequencing (MDS) identified Acanthamoeba genomic fragments in the vitreous sample. Multiple intravitreal voriconazole injections were performed and achieved partial suppression of lesion growth. Subsequent dual therapy of oral voriconazole and trimethoprim-sulfamethoxazole led to resolution of the lesions and vision improvement without further injections. Conclusions and importance This is an unusual case of unilateral Acanthamoeba-associated retinitis without concomitant corneal infection, diagnosed via unbiased DNA and RNA deep sequencing, with other etiologies ruled out by conventional approaches. Treatment with systemic and intravitreal therapy led to a successful resolution of retinitis and vision improvement. Our case demonstrates the potential of MDS as an unbiased diagnostic tool for rare ocular pathogens and the therapeutic effect of oral voriconazole with trimethoprim-sulfamethoxazole for Acanthamoeba intraocular infection.
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Affiliation(s)
- Lingling Huang
- Casey Eye Institute, Oregon Health & Science University, 515 SW Campus Drive, Portland, OR, USA
| | - Eric B. Suhler
- Casey Eye Institute, Oregon Health & Science University, 515 SW Campus Drive, Portland, OR, USA
- Veterans Affairs Portland Health Care System, 3710 Southwest US Veterans Hospital Road, Portland, OR, USA
| | - Christopher Rosenberg
- Casey Eye Institute, Oregon Health & Science University, 515 SW Campus Drive, Portland, OR, USA
| | - David Ta Kim
- University of British Columbia, 2550 Willow Street, Vancouver, British Columbia, Canada
| | - Kevin L. Winthrop
- Division of Infectious Diseases, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR, USA
| | - Thuy Doan
- Francis I. Proctor Foundation, University of California San Francisco, 490 Illinois Street, San Francisco, CA, USA
| | - Phoebe Lin
- Casey Eye Institute, Oregon Health & Science University, 515 SW Campus Drive, Portland, OR, USA
- Cole Eye Institute, Cleveland Clinic, 9500 Euclid Ave, Cleveland, OH, USA
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Sharma C, Khurana S, Megha K, Thakur A, Bhatia A, Gupta A. Assessment of pathogenic potential of Acanthamoeba isolates by in vitro and in vivo tests. Parasitol Res 2023; 122:2109-2118. [PMID: 37418019 DOI: 10.1007/s00436-023-07910-7] [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: 04/07/2023] [Accepted: 06/20/2023] [Indexed: 07/08/2023]
Abstract
Acanthamoeba are free-living protozoa present ubiquitously in numerous environmental reservoirs that exist as an actively feeding trophozoite or a dormant cyst stage. The pathogenic Acanthamoeba are known to cause Acanthamoeba keratitis (AK) and granulomatous amoebic encephalitis (GAE). Despite their omnipresence, the number of infections is quite low. The reason behind this low frequency of Acanthamoeba infections could be the existence of many non-pathogenic strains or a successful host immune response to these infections. Studies in the past have proposed a few physiological parameters for the differentiation of pathogenic and non-pathogenic strains. Additionally, in vivo experiments are known to play an essential role in understanding the virulence of parasites, immunological aspects, and disease pathogenesis. The thermotolerance (30 °C, 37 °C, and 40 °C) and osmotolerance (0.5 M, 1 M, and 1.5 M) tests were performed on 43 Acanthamoeba isolates from patients with keratitis (n = 22), encephalitis (n = 5), and water samples (n = 16). In addition, the genotype of 10 Acanthamoeba isolates (keratitis (n = 2), encephalitis (n = 2), water (n = 6)) was determined and were then evaluated for pathogenicity on mouse model by inducing Acanthamoeba keratitis and amoebic encephalitis. The results of the thermotolerance and osmotolerance assays categorized 29/43 (67.4%) isolates as pathogenic, 8 as low pathogenic (18.6%), and the remaining 6 (13.9%) as non-pathogenic. The 10 Acanthamoeba isolates were categorized as T11 (5 isolates), T5 (2 isolates), T4 (2 isolates), and T10 (1 isolate) genotypes. Out of 10 Acanthamoeba isolates, 9 were successful in establishing AK, amoebic encephalitis, or both in the mice model, and a single isolate was found non-pathogenic. Two isolates from water samples were non-pathogenic in the physiological tests but successfully established Acanthamoeba infection in the mice model. The results of the physiological assays and in vivo experiments were analogous for 7 isolates while 1 isolate from the water was low pathogenic in the physiological assays but failed to produce pathogenicity during in vivo experiments. The physiological parameters are not very dependable to test the pathogenic potential of Acanthamoeba isolates, and thus results must always be validated by in vivo experiments. There is no infallible approach for determining the potential pathogenicity of environmental isolates of Acanthamoeba because several parameters regulate the pathogenic potential.
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Affiliation(s)
- Chayan Sharma
- Department of Medical Parasitology, Postgraduate Institute of Medical Education & Research, Chandigarh, 160012, India
| | - Sumeeta Khurana
- Department of Medical Parasitology, Postgraduate Institute of Medical Education & Research, Chandigarh, 160012, India.
| | - Kirti Megha
- Department of Medical Parasitology, Postgraduate Institute of Medical Education & Research, Chandigarh, 160012, India
| | - Anchal Thakur
- Advanced Eye Centre, Postgraduate Institute of Medical Education & Research, Chandigarh, 160012, India
| | - Alka Bhatia
- Department of Experimental Medicine and Biotechnology, Postgraduate Institute of Medical Education & Research, Chandigarh, 160012, India
| | - Amit Gupta
- Advanced Eye Centre, Postgraduate Institute of Medical Education & Research, Chandigarh, 160012, India
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Ledbetter EC, Dong L. Susceptibility of the Intact and Traumatized Feline Cornea to In Vitro Binding and Invasion by Acanthamoeba castellanii. Cornea 2023; 42:624-629. [PMID: 36518074 PMCID: PMC10060048 DOI: 10.1097/ico.0000000000003220] [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: 10/04/2022] [Revised: 11/02/2022] [Accepted: 11/16/2022] [Indexed: 12/23/2022]
Abstract
PURPOSE Acanthamoeba castellanii ( A. castellanii ) displays host specificity at the level of the ocular surface. This study determined the susceptibility of the intact and traumatized feline cornea to A. castellanii binding and invasion relative to other host species with established susceptibility and resistance to Acanthamoeba binding. METHODS Full-thickness buttons of fresh feline, porcine, and canine corneas were prepared. The corneal epithelium was confirmed intact by fluorescein staining or lightly scarified with a 25-G needle to simulate corneal trauma. Acanthamoeba castellanii was axenically cultivated. Corneal buttons were incubated with the parasite suspension or parasite-free medium for 18 hours at 35°C. Corneal buttons were rinsed, fixed, and processed for histopathology and immunohistochemistry using immunoperoxidase and immunofluorescence methods of amoeba detection. RESULTS Numerous amoebae were bound to feline and porcine corneas incubated with parasites. In both intact and traumatized corneas, amoebae were detected at all levels in the corneal epithelium and within the anterior stroma. In traumatized corneal sections, amoebae were frequently present in regions of epithelial damage. Corneal architecture was well-preserved in sections incubated with parasite-free medium; however, epithelial cell sloughing, separation of epithelial layers, and epithelial detachment from the stroma were observed in corneas incubated with amoebae. Intact and traumatized canine corneas were relatively free of adherent amoebae, and corneal architecture was indistinguishable between sections incubated with the parasite suspension and parasite-free medium. CONCLUSIONS The feline cornea is highly susceptible to in vitro binding and invasion by A. castellanii . Acanthamoeba binding to the feline cornea does not require a previous epithelial defect.
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Affiliation(s)
- Eric C. Ledbetter
- Departments of Clinical Sciences; and Biomedical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY
| | - Longying Dong
- Departments of Clinical Sciences; and Biomedical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY
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Kim MJ, Jo HJ, Sohn HJ, Shin HJ, Quan FS, Kong HH, Moon EK. Evaluating the Diagnostic Potential of Chorismate Mutase Poly-Clonal Peptide Antibody for the Acanthamoeba Keratitis in an Animal Model. Pathogens 2023; 12:pathogens12040526. [PMID: 37111412 PMCID: PMC10145577 DOI: 10.3390/pathogens12040526] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 03/17/2023] [Accepted: 03/24/2023] [Indexed: 03/31/2023] Open
Abstract
Acanthamoeba spp. is the causative agent of Acanthamoeba keratitis (AK), a vision-threatening parasitic disease whose primary risk factor has been attributed to poor contact lens hygiene. Unfortunately, differential diagnosis of AK is challenging as the clinical manifestations for AK are similar to those of bacterial, fungal, or even viral keratitis. Since delayed AK diagnosis can incur permanent vision impairment, a rapid and sensitive diagnostic method is urgently needed. Here, the diagnostic potential of polyclonal antibodies targeting the chorismate mutase (CM) of Acanthamoeba spp. was evaluated in AK animal models. CM antibody specificity against Acanthamoeba trophozoites and cysts was confirmed by immunocytochemistry after co-culturing Acanthamoeba with Fusarium solani, Pseudomonas aeruginosa, and Staphylococcus aureus, and human corneal epithelial (HCE) cells. Enzyme-linked immunosorbent assay (ELISA) was performed using CM-specific immune sera raised in rabbits, which demonstrated that the antibodies specifically interacted with the Acanthamoeba trophozoites and cysts in a dose-dependent manner. To evaluate the diagnostic potential of the CM antibody, AK animal models were established by incubating contact lenses with an inoculum containing A. castellanii trophozoites and subsequently overlaying these lenses onto the corneas of BALB/c mice for 7 and 21 days. The CM antibody specifically detected Acanthamoeba antigens in the murine lacrimal and eyeball tissue lysates at both time points. Our findings underscore the importance of antibody-based AK diagnosis, which could enable early and differential AK diagnosis in clinical settings.
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Affiliation(s)
- Min-Jeong Kim
- Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul 02447, Republic of Korea
| | - Hye-Jeong Jo
- Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul 02447, Republic of Korea
| | - Hae-Jin Sohn
- Department of Microbiology, Ajou University School of Medicine, Suwon 16499, Republic of Korea
| | - Ho-Joon Shin
- Department of Microbiology, Ajou University School of Medicine, Suwon 16499, Republic of Korea
| | - Fu-Shi Quan
- Department of Medical Zoology, School of Medicine, Kyung Hee University, Seoul 02447, Republic of Korea
- Medical Research Center for Bioreaction to Reactive Oxygen Species and Biomedical Science Institute, Core Research Institute (CRI), Kyung Hee University, Seoul 02447, Republic of Korea
| | - Hyun-Hee Kong
- Department of Parasitology, Dong-A University College of Medicine, Busan 49201, Republic of Korea
| | - Eun-Kyung Moon
- Department of Medical Zoology, School of Medicine, Kyung Hee University, Seoul 02447, Republic of Korea
- Correspondence:
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Ávila-Blanco ME, Aguilera-Martínez SL, Ventura-Juarez J, Pérez-Serrano J, Casillas-Casillas E, Barba-Gallardo LF. Effectiveness of Polyclonal Antibody Immunoconjugate Treatment with Propamidine Isethionate for Amoebic Keratitis in Golden Hamsters. J Parasitol Res 2023; 2023:3713368. [PMID: 37143958 PMCID: PMC10154091 DOI: 10.1155/2023/3713368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 03/13/2023] [Accepted: 04/04/2023] [Indexed: 05/06/2023] Open
Abstract
Acanthamoeba griffini is known to cause amoebic keratitis (AK); its main causes are inadequate hygiene when contact lenses are handled and/or its prolonged use at night, as well as the use of contact lenses during underwater activities. The most used treatment for AK is the combination of propamidine isethionate combined with polyhexamethylene biguanide, which disrupts the cytoplasmic membrane, and damages cellular components and respiratory enzymes. We proposed an immunoconjugate treatment obtained from Acanthamoeba immunized rabbit serum combined with propamidine isethionate; the corneas of hamsters inoculated with A. griffini (MYP2004) were treated with the combined, at 1, 2, and 3 weeks. Propamidine isethionate is frequently used for AK treatment, in vivo study we are found IL-1β and IL-10 expression and caspase 3 activity is significantly increased with respect to the group that was inoculated with the amoeba without receiving any treatment, suggesting that it may be an effect of the toxicity of this drug on the corneal tissue. Application of the immunoconjugate showed enhanced amoebicidal and anti-inflammatory activities, with comparison to propamidine isethionate only. The aim of this study is to evaluate the effect of the immunoconjugate of propamidine isethionate and polyclonal antibodies as a treatment of AK in golden hamsters (Mesocricetus auratus).
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Detection of Acanthamoeba from Acanthamoeba Keratitis Mouse Model Using Acanthamoeba-Specific Antibodies. Microorganisms 2022; 10:microorganisms10091711. [PMID: 36144313 PMCID: PMC9500705 DOI: 10.3390/microorganisms10091711] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 08/02/2022] [Accepted: 08/22/2022] [Indexed: 11/18/2022] Open
Abstract
Although the prevalence of Acanthamoeba keratitis (AK) is rare, its incidence in contact lens wearers has increased. Acanthamoeba infections can lead to the loss of vision if the diagnosis and treatment are delayed. In this study, we investigated the diagnostic potential of two antibodies raised against the adenylyl cyclase-associated protein (ACAP) and periplasmic binding protein (PBP) of A. castellanii in the AK mouse model. The specificity of ACAP and PBP antibodies to Acanthamoeba was confirmed by immunocytochemistry. AK mouse models were produced by corneal infections with A. castellanii trophozoites for 7 days and 21 days. Enzyme-linked immunosorbent assay results revealed that both ACAP and PBP antibodies successfully detected Acanthamoeba antigens in the tears and eyeball lysates of the AK mouse model. The detection levels of Acanthamoeba antigens were similar at both infection time points. Anti-Acanthamoeba IgG, IgA, and IgM antibodies were evaluated from the sera of the AK mouse model. Notably, IgM and IgA antibody responses were highest and lowest at both time points, respectively. Our findings revealed that both ACAP and PBP antibodies could detect Acanthamoeba antigens in the tears and eyeball lysates of the AK mouse model. These results provide important information for understanding Acanthamoeba infections and developing a new diagnostic tool for AK.
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Kim MJ, Chu KB, Lee HA, Quan FS, Kong HH, Moon EK. Detection of Acanthamoeba spp. using carboxylesterase antibody and its usage for diagnosing Acanthamoeba-keratitis. PLoS One 2022; 17:e0262223. [PMID: 34986189 PMCID: PMC8730387 DOI: 10.1371/journal.pone.0262223] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 12/20/2021] [Indexed: 11/30/2022] Open
Abstract
Contact lens usage has contributed to increased incidence rates of Acanthamoeba keratitis (AK), a serious corneal infection that can lead to blindness. Since symptoms associated with AK closely resemble those incurred by bacterial or fungal keratitis, developing a diagnostic method enabling rapid detection with a high degree of Acanthamoeba-specificity would be beneficial. Here, we produced a polyclonal antibody targeting the carboxylesterase (CE) superfamily protein secreted by the pathogenic Acanthamoeba and evaluated its diagnostic potential. Western blot analysis revealed that the CE antibody specifically interacts with the cell lysates and conditioned media of pathogenic Acanthamoeba, which were not observed from the cell lysates and conditioned media of human corneal epithelial (HCE) cells, Fusarium solani, Staphylococcus aureus, and Pseudomonas aeruginosa. High titers of A. castellanii-specific antibody production were confirmed sera of immunized mice via ELISA, and these antibodies were capable of detecting A. castellanii from the cell lysates and their conditioned media. The specificity of the CE antibody was further confirmed on A. castellanii trophozoites and cysts co-cultured with HCE cells, F. solani, S. aureus, and P. aeruginosa using immunocytochemistry. Additionally, the CE antibody produced in this study successfully interacted with 7 different Acanthamoeba species. Our findings demonstrate that the polyclonal CE antibody specifically detects multiple species belong to the genus Acanthamoeba, thus highlighting its potential as AK diagnostic tool.
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Affiliation(s)
- Min-Jeong Kim
- Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul, Republic of Korea
| | - Ki-Back Chu
- Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul, Republic of Korea
| | - Hae-Ahm Lee
- Medical Research Center for Bioreaction to Reactive Oxygen Species and Biomedical Science Institute, School of Medicine, Graduate school, Kyung Hee University, Seoul, Republic of Korea
| | - Fu-Shi Quan
- Medical Research Center for Bioreaction to Reactive Oxygen Species and Biomedical Science Institute, School of Medicine, Graduate school, Kyung Hee University, Seoul, Republic of Korea
- Department of Medical Zoology, Kyung Hee University School of Medicine, Seoul, Republic of Korea
| | - Hyun-Hee Kong
- Department of Parasitology, Dong-A University College of Medicine, Busan, Republic of Korea
| | - Eun-Kyung Moon
- Department of Medical Zoology, Kyung Hee University School of Medicine, Seoul, Republic of Korea
- * E-mail:
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Kim MJ, Lee HA, Quan FS, Kong HH, Moon EK. Characterization of a Peptide Antibody Specific to the Adenylyl Cyclase-Associated Protein of Acanthamoeba castellanii. THE KOREAN JOURNAL OF PARASITOLOGY 2022; 60:7-14. [PMID: 35247949 PMCID: PMC8898646 DOI: 10.3347/kjp.2022.60.1.7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Accepted: 02/10/2022] [Indexed: 11/23/2022]
Abstract
Acanthamoeba keratitis (AK) is a rare infectious disease and accurate diagnosis has remained arduous as clinical manifestations of AK were similar to keratitis of viral, bacterial, or fungal origins. In this study, we described the production of a polyclonal peptide antibody against the adenylyl cyclase-associated protein (ACAP) of A. castellanii, and evaluated its differential diagnostic potential. Enzyme-linked immunosorbent assay revealed high titers of A. castellanii-specific IgG and IgA antibodies being present in low dilutions of immunized rabbit serum. Western blot analysis revealed that the ACAP antibody specifically interacted with A. castellanii, while not interacting with human corneal epithelial (HCE) cells and other causes of keratitis such as Fusarium solani, Pseudomonas aeruginosa, and Staphylococcus aureus. Immunocytochemistry (ICC) results confirmed the specific detection of trophozoites and cysts of A. castellanii co-cultured with HCE cells. The ACAP antibody also specifically interacted with the trophozoites and cysts of 5 other Acanthamoeba species. These results indicate that the ACAP antibody of A. castellanii can specifically detect multiple AK-causing members belonging to the genus Acanthamoeba and may be useful for differentially diagnosing Acanthamoeba infections.
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Affiliation(s)
- Min-Jeong Kim
- Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul 02447, Korea
| | - Hae-Ahm Lee
- Medical Research Center for Bioreaction to Reactive Oxygen Species and Biomedical Science Institute, School of Medicine, Graduate school, Kyung Hee University, Seoul 02447, Korea
| | - Fu-Shi Quan
- Medical Research Center for Bioreaction to Reactive Oxygen Species and Biomedical Science Institute, School of Medicine, Graduate school, Kyung Hee University, Seoul 02447, Korea.,Department of Medical Zoology, Kyung Hee University School of Medicine, Seoul 02447, Korea
| | - Hyun-Hee Kong
- Department of Parasitology, Dong-A University College of Medicine, Busan 49201, Korea
| | - Eun-Kyung Moon
- Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul 02447, Korea
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12
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Ung L, Chodosh J. Foundational concepts in the biology of bacterial keratitis. Exp Eye Res 2021; 209:108647. [PMID: 34097906 PMCID: PMC8595513 DOI: 10.1016/j.exer.2021.108647] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 04/28/2021] [Accepted: 05/27/2021] [Indexed: 12/12/2022]
Abstract
Bacterial infections of the cornea, or bacterial keratitis (BK), are notorious for causing rapidly fulminant disease and permanent vision loss, even among treated patients. In the last sixty years, dramatic upward trajectories in the frequency of BK have been observed internationally, driven in large part by the commercialization of hydrogel contact lenses in the late 1960s. Despite this worsening burden of disease, current evidence-based therapies for BK - including broad-spectrum topical antibiotics and, if indicated, topical corticosteroids - fail to salvage vision in a substantial proportion of affected patients. Amid growing concerns of rapidly diminishing antibiotic utility, there has been renewed interest in urgently needed novel treatments that may improve clinical outcomes on an individual and public health level. Bridging the translational gap in the care of BK requires the identification of new therapeutic targets and rational treatment design, but neither of these aims can be achieved without understanding the complex biological processes that determine how bacterial corneal infections arise, progress, and resolve. In this chapter, we synthesize the current wealth of human and animal experimental data that now inform our understanding of basic BK pathophysiology, in context with modern concepts in ocular immunology and microbiology. By identifying the key molecular determinants of clinical disease, we explore how novel treatments can be developed and translated into routine patient care.
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Affiliation(s)
- Lawson Ung
- Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA; Infectious Disease Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA; Department of Epidemiology, Harvard T. H. Chan School of Public Health, Boston, MA, USA
| | - James Chodosh
- Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA; Infectious Disease Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA.
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13
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Redd TK, Talbott M, Cevallos V, Lalitha P, Seitzman GD, Lietman TM, Keenan JD. In Vitro Comparison of the Acanthamoeba Cysticidal Activity of Povidone Iodine, Natamycin, and Chlorhexidine. OPHTHALMOLOGY SCIENCE 2021; 1:100025. [PMID: 36249301 PMCID: PMC9560639 DOI: 10.1016/j.xops.2021.100025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 04/20/2021] [Accepted: 04/23/2021] [Indexed: 11/30/2022]
Affiliation(s)
- Travis K. Redd
- Francis I. Proctor Foundation, University of California, San Francisco
- Casey Eye Institute, Oregon Health & Science University, Portland, Oregon
| | - Maya Talbott
- Francis I. Proctor Foundation, University of California, San Francisco
| | - Vicky Cevallos
- Francis I. Proctor Foundation, University of California, San Francisco
| | | | - Gerami D. Seitzman
- Francis I. Proctor Foundation, University of California, San Francisco
- Department of Ophthalmology, University of California, San Francisco
| | - Thomas M. Lietman
- Francis I. Proctor Foundation, University of California, San Francisco
- Department of Ophthalmology, University of California, San Francisco
| | - Jeremy D. Keenan
- Francis I. Proctor Foundation, University of California, San Francisco
- Department of Ophthalmology, University of California, San Francisco
- Correspondence: Jeremy D. Keenan, MD, MPH, Francis I. Proctor Foundation, University of California, San Francisco, 490 Illinois Street, San Francisco, CA 94107.
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14
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Lee HA, Chu KB, Kim MJ, Quan FS, Kong HH, Moon EK. Chorismate mutase peptide antibody enables specific detection of Acanthamoeba. PLoS One 2021; 16:e0250342. [PMID: 33891646 PMCID: PMC8064552 DOI: 10.1371/journal.pone.0250342] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Accepted: 04/05/2021] [Indexed: 11/19/2022] Open
Abstract
Accurate and rapid diagnosis of Acanthamoeba keratitis (AK) is difficult. Although the diagnostic procedure for AK has improved, further development and effective diagnostic tool utilization for AK need to continue. Chorismate mutase is a key regulatory enzyme involved in the shikimate pathway, a metabolic pathway absent in mammals but central for amino acid biosynthesis in bacteria, fungi, algae, and plants. In this study, we describe the identification and production of a polyclonal peptide antibody targeting chorismate mutase secreted by A. castellanii, which could be used for AK diagnosis. Western blot was performed using the protein lysates and conditioned media of the human corneal epithelial (HCE) cells, non-pathogenic Acanthamoeba, pathogenic Acanthamoeba, clinical isolate of Acanthamoeba spp., and other causes of keratitis such as Fusarium solani, Pseudomonas aeruginosa, and Staphylococcus aureus. Polyclonal antibodies raised against A. castellanii chorismate mutase specifically interacted with lysates of Acanthamoeba origin and their culture media, while such interactions were not observed from other samples. Acanthamoeba-specificity of chorismate mutase was also confirmed using immunocytochemistry after co-culturing Acanthamoeba with HCE cells. Specific binding of the chorismate mutase antibody to Acanthamoeba was observed, which were absent in the case of HCE cells. These results indicate that the chorismate mutase antibody of Acanthamoeba may serve as a method for rapid and differential Acanthamoeba identification.
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Affiliation(s)
- Hae-Ahm Lee
- Medical Research Center for Bioreaction to Reactive Oxygen Species and Biomedical Science Institute, School of Medicine, Graduate School, Kyung Hee University, Seoul, Korea
| | - Ki-Back Chu
- Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul, Korea
| | - Min-Jeong Kim
- Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul, Korea
| | - Fu-Shi Quan
- Medical Research Center for Bioreaction to Reactive Oxygen Species and Biomedical Science Institute, School of Medicine, Graduate School, Kyung Hee University, Seoul, Korea
- Department of Medical Zoology, Kyung Hee University School of Medicine, Seoul, Korea
| | - Hyun-Hee Kong
- Department of Parasitology, Dong-A University College of Medicine, Busan, Korea
| | - Eun-Kyung Moon
- Department of Medical Zoology, Kyung Hee University School of Medicine, Seoul, Korea
- * E-mail:
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15
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Niederkorn JY. The biology of Acanthamoeba keratitis. Exp Eye Res 2020; 202:108365. [PMID: 33221372 DOI: 10.1016/j.exer.2020.108365] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 11/10/2020] [Accepted: 11/13/2020] [Indexed: 12/31/2022]
Abstract
Acanthamoeba keratitis (AK) is a rare protozoal infection of the cornea. At least eight species of Acanthamoeba are known to cause this sight-threatening disease of the ocular surface. Acanthamoeba spp. exist in a wide array of niches ranging from thermal springs to under ice and every conceivable habitat in between. Contact lens wear is the leading risk factor for AK and is practiced by over 30 million individuals in the United States, yet the incidence of AK is less than 33 cases per one million contact lens wearers. Serological studies have reported that 90%-100% of individuals with no history of AK possess antibodies specific for Acanthamoeba antigens indicating that exposure to this organism is commonplace, yet disease is remarkably rare. Animal studies have shed light on the pathobiology and immunobiology of AK and indicate that a constellation of factors including the ocular surface microbiome and the microbiome of Acanthamoeba itself contribute to the pathogenesis of AK. Interesting, secretory antibodies produced by the adaptive immune response can prevent the initiation of corneal infection, but once Acanthamoeba trophozoites breach the corneal epithelium the adaptive immune system is helpless in altering the course of AK. It has been almost 50 years since AK was first described, yet many questions remain unanswered about this curious and enigmatic disease of the ocular surface.
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Affiliation(s)
- Jerry Y Niederkorn
- Department of Ophthalmology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390, USA.
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16
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Production of a polyclonal antibody against inosine-uridine preferring nucleoside hydrolase of Acanthamoeba castellanii and its access to diagnosis of Acanthamoeba keratitis. PLoS One 2020; 15:e0239867. [PMID: 32997695 PMCID: PMC7526901 DOI: 10.1371/journal.pone.0239867] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Accepted: 09/14/2020] [Indexed: 11/21/2022] Open
Abstract
Acanthamoeba keratitis (AK) is a rare disease but its prevalence throughout the globe continues to grow, primarily due to increased contact lens usage. Since early-stage symptoms associated with AK closely resemble those from other corneal infections, accurate diagnosis is difficult and this often results in delayed treatment and exacerbation of the disease, which can lead to permanent visual impairment. Accordingly, developing a rapid Acanthamoeba–specific diagnostic method is highly desired. In the present study, a rapid and differential method for AK diagnosis was developed using the secretory proteins derived from the pathogenic Acanthamoeba. Among the vast quantities of proteins secreted by the pathogenic Acanthamoeba, an open reading frame of the inosine-uridine preferring nucleoside hydrolase (IPNH) gene was obtained. After expressing and purifying the IPNH protein using the pGEX 4T-3 vector system, mice were immunized with the purified proteins for polyclonal antibody generation. Western blot was performed using protein lysates of the human corneal cell, non-pathogenic amoeba, pathogenic amoeba, and clinical amoeba isolate along with lysates from other causes of keratitis such as Staphylococcus aureus, Pseudomonas aeruginosa, and Fusarium solani to confirm Acanthamoeba-specificity. Western blot using the polyclonal IPNH antibody revealed that IPNH was Acanthamoeba-specific since these proteins were only observed in lysates of Acanthamoeba origin or its culture media. Our findings indicate that the IPNH antibody of Acanthamoeba may serve as a potential agent for rapid and differential AK diagnosis.
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Crothers JW, Hsu L, Marty FM. Fulminant Acanthamoeba castellanii Encephalitis in an Ibrutinib-Treated Patient. Open Forum Infect Dis 2020; 7:ofaa025. [PMID: 32055639 PMCID: PMC7008473 DOI: 10.1093/ofid/ofaa025] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Accepted: 01/17/2020] [Indexed: 12/17/2022] Open
Abstract
We report a case of fulminant Acanthamoeba castellanii encephalitis in a patient with chronic lymphocytic leukemia treated with ibrutinib. The unusually rapid neurologic decline and fatal outcome observed are probably related to alterations in immunologic function associated with inhibition of Bruton tyrosine kinase.
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Affiliation(s)
| | - Liangge Hsu
- Brigham and Women's Hospital, Boston, Massachusetts, USA
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18
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Shi L, Hager T, Fries FN, Daas L, Holbach L, Hofmann-Rummelt C, Zemova E, Seitz B, Szentmáry N. Reactive uveitis, retinal vasculitis and scleritis as ocular end-stage of Acanthamoeba keratitis: a histological study. Int J Ophthalmol 2019; 12:1966-1971. [PMID: 31850183 DOI: 10.18240/ijo.2019.12.20] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Accepted: 08/21/2019] [Indexed: 11/23/2022] Open
Abstract
We analysed histologically two Acanthamoeba keratitis (AK) eyes with anterior and posterior segment inflammation and blindness. Two enucleated eyes of 2 patients (age 45 and 51y) with AK (PCR of epithelial abrasion positive) were analysed. Histological analysis was performed using hematoxylin-eosin, periodic acid-Schiff and Gömöri-methenamine silver staining. We could not observe Acanthamoeba trophozoites or cysts neither in the cornea nor in other ocular tissues. Meanwhile, we found uveitis, retinal vasculitis and scleritis in these eyes, due to the long-standing, recalcitrant AK. So in this stage of AK, systemic immune suppression may be necessary for a longer time period.
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Affiliation(s)
- Lei Shi
- Department of Ophthalmology, Saarland University Medical Center, Homburg/Saar 66424, Germany.,Department of Ophthalmology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230001, Anhui Province, P.R. China
| | - Tobias Hager
- Department of Ophthalmology, Saarland University Medical Center, Homburg/Saar 66424, Germany
| | - Fabian Norbert Fries
- Department of Ophthalmology, Saarland University Medical Center, Homburg/Saar 66424, Germany
| | - Loay Daas
- Department of Ophthalmology, Saarland University Medical Center, Homburg/Saar 66424, Germany
| | - Leonard Holbach
- Department of Ophthalmology, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen 91052, Germany
| | - Carmen Hofmann-Rummelt
- Department of Ophthalmology, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen 91052, Germany
| | - Elena Zemova
- Department of Ophthalmology, Saarland University Medical Center, Homburg/Saar 66424, Germany
| | - Berthold Seitz
- Department of Ophthalmology, Saarland University Medical Center, Homburg/Saar 66424, Germany
| | - Nóra Szentmáry
- Department of Ophthalmology, Saarland University Medical Center, Homburg/Saar 66424, Germany.,Department of Ophthalmology, Semmelweis University, Budapest 1093, Hungary
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19
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Two Potential Clinical Applications of Origami-Based Paper Devices. Diagnostics (Basel) 2019; 9:diagnostics9040203. [PMID: 31779180 PMCID: PMC6963803 DOI: 10.3390/diagnostics9040203] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2019] [Revised: 11/21/2019] [Accepted: 11/25/2019] [Indexed: 01/04/2023] Open
Abstract
Detecting small amounts of analyte in clinical practice is challenging because of deficiencies in specimen sample availability and unsuitable sampling environments that prevent reliable sampling. Paper-based analytical devices (PADs) have successfully been used to detect ultralow amounts of analyte, and origami-based PADs (O-PADs) offer advantages that may boost the overall potential of PADs in general. In this study, we investigated two potential clinical applications for O-PADs. The first O-PAD we investigated was an origami-based enzyme-linked immunosorbent assay (ELISA) system designed to detect different concentrations of rabbit IgG. This device was designed with four wing structures, each of which acted as a reagent loading zone for pre-loading ELISA reagents, and a central test sample loading zone. Because this device has a low limit of detection (LOD), it may be suitable for detecting IgG levels in tears from patients with a suspected viral infection (such as herpes simplex virus (HSV)). The second O-PAD we investigated was designed to detect paraquat levels to determine potential poisoning. To use this device, we sequentially folded each of two separate reagent zones, one preloaded with NaOH and one preloaded with ascorbic acid (AA), over the central test zone, and added 8 µL of sample that then flowed through each reagent zone and onto the central test zone. The device was then unfolded to read the results on the test zone. The three folded layers of paper provided a moist environment not achievable with conventional paper-based ELISA. Both O-PADs were convenient to use because reagents were preloaded, and results could be observed and analyzed with image analysis software. O-PADs expand the testing capacity of simpler PADs while leveraging their characteristic advantages of convenience, cost, and ease of use, particularly for point-of-care diagnosis.
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20
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Betanzos A, Bañuelos C, Orozco E. Host Invasion by Pathogenic Amoebae: Epithelial Disruption by Parasite Proteins. Genes (Basel) 2019; 10:E618. [PMID: 31416298 PMCID: PMC6723116 DOI: 10.3390/genes10080618] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 04/25/2019] [Accepted: 04/29/2019] [Indexed: 02/07/2023] Open
Abstract
The epithelium represents the first and most extensive line of defence against pathogens, toxins and pollutant agents in humans. In general, pathogens have developed strategies to overcome this barrier and use it as an entrance to the organism. Entamoeba histolytica, Naegleriafowleri and Acanthamoeba spp. are amoebae mainly responsible for intestinal dysentery, meningoencephalitis and keratitis, respectively. These amoebae cause significant morbidity and mortality rates. Thus, the identification, characterization and validation of molecules participating in host-parasite interactions can provide attractive targets to timely intervene disease progress. In this work, we present a compendium of the parasite adhesins, lectins, proteases, hydrolases, kinases, and others, that participate in key pathogenic events. Special focus is made for the analysis of assorted molecules and mechanisms involved in the interaction of the parasites with epithelial surface receptors, changes in epithelial junctional markers, implications on the barrier function, among others. This review allows the assessment of initial host-pathogen interaction, to correlate it to the potential of parasite invasion.
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Affiliation(s)
- Abigail Betanzos
- Consejo Nacional de Ciencia y Tecnología (CONACYT), Mexico City 03940, Mexico
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), Mexico City 07360, Mexico
| | - Cecilia Bañuelos
- Coordinación General de Programas de Posgrado Multidisciplinarios, Programa de Doctorado Transdisciplinario en Desarrollo Científico y Tecnológico para la Sociedad, CINVESTAV-IPN, Mexico City 07360, Mexico
| | - Esther Orozco
- Departamento de Infectómica y Patogénesis Molecular, CINVESTAV-IPN, Mexico City 07360, Mexico.
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21
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Lass A, Guerrero M, Li X, Karanis G, Ma L, Karanis P. Detection of Acanthamoeba spp. in water samples collected from natural water reservoirs, sewages, and pharmaceutical factory drains using LAMP and PCR in China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 584-585:489-494. [PMID: 28131444 DOI: 10.1016/j.scitotenv.2017.01.046] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Revised: 01/05/2017] [Accepted: 01/07/2017] [Indexed: 06/06/2023]
Abstract
Various species of amoebas belonging to the genus Acanthamoeba are widely distributed in many parts of the world. Some strains of these protozoans may exist as parasites and pose risks to human health as causative agents of serious human diseases. Currently in China there is a lack of information about the distribution of Acanthamoeba strains in the environment. Accordingly, 261 environmental water samples taken from rivers, sewage, and pharmaceutical factory drains were collected in Qinghai Province, China. The material was filtered and then analysed with both LAMP and PCR assays. Of the samples examined, Acanthamoeba DNA was found in 32 (14.68%) samples with the use of LAMP; in 13 of these samples, DNA from this amoeba was also detected using PCR. Sequencing of selected positive samples confirmed that the PCR products were fragments of the Acanthamoeba 18S rRNA gene and that isolates represent the T4 genotype, known as the most common strain related to AK cases. The results indicate that surface water, as well as water taken from sewage and pharmaceutical drains, may be a source of acanthamoebic strains potentially pathogenic for humans in China. It has been also demonstrated that LAMP assays is more sensitive than PCR and can be regarded as useful tool for screening the environment for Acanthamoeba spp.
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Affiliation(s)
- Anna Lass
- State Key Laboratory of Plateau Ecology and Agriculture, Center for Biomedicine and Infectious Disease, Qinghai Academy of Animal Sciences and Veterinary Medicine, Medical School of Qinghai University Xining, 1#Wei'er Road, Qinghai, Biological Scientific Estate Garden, Xining 810016, PR China; Department of Tropical Parasitology, Institute of Maritime and Tropical Medicine in Gdynia, Medical University of Gdansk, 9b Powstania Styczniowego Str, 81-519 Gdynia, Poland
| | - Milena Guerrero
- State Key Laboratory of Plateau Ecology and Agriculture, Center for Biomedicine and Infectious Disease, Qinghai Academy of Animal Sciences and Veterinary Medicine, Medical School of Qinghai University Xining, 1#Wei'er Road, Qinghai, Biological Scientific Estate Garden, Xining 810016, PR China; Research Group of Functional Materials and Catalysis, GIMFC, Universidad de Nariño, Calle 18 Cra. 50, Campus Torobajo, Pasto-Colombia. Doctorate in Biotechnology, Universidad Nacional de Colombia, Bogotá D.C., Colombia
| | - Xiuping Li
- State Key Laboratory of Plateau Ecology and Agriculture, Center for Biomedicine and Infectious Disease, Qinghai Academy of Animal Sciences and Veterinary Medicine, Medical School of Qinghai University Xining, 1#Wei'er Road, Qinghai, Biological Scientific Estate Garden, Xining 810016, PR China
| | - Gabriele Karanis
- State Key Laboratory of Plateau Ecology and Agriculture, Center for Biomedicine and Infectious Disease, Qinghai Academy of Animal Sciences and Veterinary Medicine, Medical School of Qinghai University Xining, 1#Wei'er Road, Qinghai, Biological Scientific Estate Garden, Xining 810016, PR China; Qinghai University Affiliated Hospital, Xining City 810016, Qinghai Province, PR China
| | - Liqing Ma
- State Key Laboratory of Plateau Ecology and Agriculture, Center for Biomedicine and Infectious Disease, Qinghai Academy of Animal Sciences and Veterinary Medicine, Medical School of Qinghai University Xining, 1#Wei'er Road, Qinghai, Biological Scientific Estate Garden, Xining 810016, PR China
| | - Panagiotis Karanis
- State Key Laboratory of Plateau Ecology and Agriculture, Center for Biomedicine and Infectious Disease, Qinghai Academy of Animal Sciences and Veterinary Medicine, Medical School of Qinghai University Xining, 1#Wei'er Road, Qinghai, Biological Scientific Estate Garden, Xining 810016, PR China.
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22
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Lakhundi S, Siddiqui R, Khan NA. Pathogenesis of microbial keratitis. Microb Pathog 2017; 104:97-109. [DOI: 10.1016/j.micpath.2016.12.013] [Citation(s) in RCA: 86] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Revised: 11/30/2016] [Accepted: 12/05/2016] [Indexed: 01/03/2023]
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23
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Acanthamoeba castellanii Genotype T4 Stimulates the Production of Interleukin-10 as Well as Proinflammatory Cytokines in THP-1 Cells, Human Peripheral Blood Mononuclear Cells, and Human Monocyte-Derived Macrophages. Infect Immun 2016; 84:2953-62. [PMID: 27481240 PMCID: PMC5038060 DOI: 10.1128/iai.00345-16] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Accepted: 07/24/2016] [Indexed: 12/11/2022] Open
Abstract
Free-living amoebae of the genus Acanthamoeba can cause severe and chronic infections in humans, mainly localized in immune privileged sites, such as the brain and the eye. Monocytes/macrophages are thought to be involved in Acanthamoeba infections, but little is known about how these facultative parasites influence their functions. The aim of this work was to investigate the effects of Acanthamoeba on human monocytes/macrophages during the early phase of infection. Here, THP-1 cells, primary human monocytes isolated from peripheral blood, and human monocyte-derived macrophages were either coincubated with trophozoites of a clinical isolate of Acanthamoeba (genotype T4) or stimulated with amoeba-derived cell-free conditioned medium. Production of proinflammatory cytokines (tumor necrosis factor alpha [TNF-α], interleukin-6 [IL-6], and IL-12), anti-inflammatory cytokine (IL-10), and chemokine (IL-8) was evaluated at specific hours poststimulation (ranging from 1.5 h to 23 h). We showed that both Acanthamoeba trophozoites and soluble amoebic products induce an early anti-inflammatory monocyte-macrophage phenotype, characterized by significant production of IL-10; furthermore, challenge with either trophozoites or their soluble metabolites stimulate both proinflammatory cytokines and chemokine production, suggesting that this protozoan infection results from the early induction of coexisting, opposed immune responses. Results reported in this paper confirm that the production of proinflammatory cytokines and chemokines by monocytes and macrophages can play a role in the development of the inflammatory response during Acanthamoeba infections. Furthermore, we demonstrate for the first time that Acanthamoeba stimulates IL-10 production in human innate immune cells, which might both promote the immune evasion of Acanthamoeba and limit the induced inflammatory response.
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24
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Song J, Huang YF, Zhang WJ, Chen XF, Guo YM. Ocular diseases: immunological and molecular mechanisms. Int J Ophthalmol 2016; 9:780-8. [PMID: 27275439 DOI: 10.18240/ijo.2016.05.25] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2015] [Accepted: 09/07/2015] [Indexed: 12/14/2022] Open
Abstract
Many factors, such as environmental, microbial and endogenous stress, antigen localization, can trigger the immunological events that affect the ending of the diverse spectrum of ocular disorders. Significant advances in understanding of immunological and molecular mechanisms have been researched to improve the diagnosis and therapy for patients with ocular inflammatory diseases. Some kinds of ocular diseases are inadequately responsive to current medications; therefore, immunotherapy may be a potential choice as an alternative or adjunctive treatment, even in the prophylactic setting. This article first provides an overview of the immunological and molecular mechanisms concerning several typical and common ocular diseases; second, the functions of immunological roles in some of systemic autoimmunity will be discussed; third, we will provide a summary of the mechanisms that dictate immune cell trafficking to ocular local microenvironment in response to inflammation.
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Affiliation(s)
- Jing Song
- Department of Ophthalmology, Affiliated Hospital of Logistics University of People's Armed Police Force, Tianjin 300161, China
| | - Yi-Fei Huang
- Department of Ophthalmology, Affiliated Hospital of Logistics University of People's Armed Police Force, Tianjin 300161, China; Department of Ophthalmology, General Hospital of PLA, Beijing 100853, China
| | - Wen-Jing Zhang
- Department of Ophthalmology, Affiliated Hospital of Logistics University of People's Armed Police Force, Tianjin 300161, China
| | - Xiao-Fei Chen
- Department of Ophthalmology, General Hospital of PLA, Beijing 100853, China
| | - Yu-Mian Guo
- Department of Ophthalmology, Affiliated Hospital of Logistics University of People's Armed Police Force, Tianjin 300161, China
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25
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Carnt N, Robaei D, Watson SL, Minassian DC, Dart JKG. The Impact of Topical Corticosteroids Used in Conjunction with Antiamoebic Therapy on the Outcome of Acanthamoeba Keratitis. Ophthalmology 2016; 123:984-90. [PMID: 26952591 DOI: 10.1016/j.ophtha.2016.01.020] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Revised: 01/13/2016] [Accepted: 01/13/2016] [Indexed: 10/22/2022] Open
Abstract
PURPOSE To examine the impact of topical corticosteroid use after the start of antiamoebic therapy (AAT) on the outcomes of Acanthamoeba keratitis (AK) therapy. DESIGN Cohort study. PARTICIPANTS A total of 196 patients diagnosed with AK at Moorfields Eye Hospital, London, between January 1991 and April 2012. In 13 patients with bilateral AK, 1 eye was randomly excluded from analysis. METHODS Patient demographics and clinical examination findings were collected both at the start of AAT and subsequently at the time that topical corticosteroid therapy was initiated. Preliminary a priori investigations were used to identify effect modifiers/confounders and extreme associations requiring consideration in multivariate regression modeling. A multivariable logistic model, optimized for assessment of corticosteroid use after the start of AAT, was used to estimate the odds ratios (ORs) of a suboptimal outcome. MAIN OUTCOME MEASURES Suboptimal outcome was defined as final visual acuity ≤20/80, corneal perforation, or the need for keratoplasty. RESULTS In multivariable analysis, restricted to 129 eyes (1 eye per patient) free of scleritis and hypopyon at the start of AAT, topical corticosteroids were not associated with worse outcomes (OR, 1.08; 95% confidence interval [CI], 0.39-3.03), even when corticosteroids had been used before the start of AAT. Risk factors significantly associated with worse outcomes were topical corticosteroid use before the start of AAT (OR, 3.85; 95% CI, 1.35-11.03), a corneal ring infiltrate (together with at least 1 other feature of AK) present at the start of AAT (OR, 5.89; 95% CI, 1.17-29.67), and age ≥33 years at the start of AAT (OR, 4.02; 95% CI, 1.46-11.06). CONCLUSIONS Many corneal specialists currently are uncertain about the risk benefit associated with the use of topical corticosteroids for the management of inflammatory complications of AK. The evidence from this study gives clinicians and patients reassurance that the potential benefits of topical corticosteroid therapy, for treating pain and discomfort, are not associated with worse outcomes when initiated after starting modern AAT. Other potential benefits, in terms of resolution of inflammatory complications, will not be demonstrated without a carefully designed randomized clinical trial.
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Affiliation(s)
- Nicole Carnt
- Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom; Save Sight Institute, University of Sydney, Sydney, Australia
| | - Dana Robaei
- Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom; Save Sight Institute, University of Sydney, Sydney, Australia
| | | | | | - John K G Dart
- National Institute of Health Research Biomedical Research Centre at Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, London, United Kingdom.
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Carnt N, Stapleton F. Strategies for the prevention of contact lens-relatedAcanthamoebakeratitis: a review. Ophthalmic Physiol Opt 2015; 36:77-92. [DOI: 10.1111/opo.12271] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Accepted: 11/23/2015] [Indexed: 11/28/2022]
Affiliation(s)
- Nicole Carnt
- Save Sight Institute; University of Sydney; Sydney Australia
- School of Optometry and Vision Science; University of New South Wales; Sydney Australia
| | - Fiona Stapleton
- School of Optometry and Vision Science; University of New South Wales; Sydney Australia
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Emerging Threats for Human Health in Poland: Pathogenic Isolates from Drug Resistant Acanthamoeba Keratitis Monitored in terms of Their In Vitro Dynamics and Temperature Adaptability. BIOMED RESEARCH INTERNATIONAL 2015; 2015:231285. [PMID: 26682216 PMCID: PMC4670850 DOI: 10.1155/2015/231285] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Revised: 10/25/2015] [Accepted: 10/27/2015] [Indexed: 11/27/2022]
Abstract
Amphizoic amoebae generate a serious human health threat due to their pathogenic potential as facultative parasites, causative agents of vision-threatening Acanthamoeba keratitis (AK). Recently, AK incidences have been reported with increasing frequency worldwide, particularly in contact lens wearers. In our study, severe cases of AK in Poland and respective pathogenic isolates were assessed at clinical, morphological, and molecular levels. Misdiagnoses and the unsuccessful treatment in other ophthalmic units delayed suitable therapy, and resistance to applied chemicals resulted in severe courses and treatment difficulties. Molecular assessment indicated that all sequenced pathogenic corneal isolates deriving from Polish patients with AK examined by us showed 98–100% homology with Acanthamoeba genotype T4, the most prevalent genotype in this human ocular infection worldwide. In vitro assays revealed that the pathogenic strains are able to grow at elevated temperature and have a wide adaptive capability. This study is our subsequent in vitro investigation on pathogenic Acanthamoeba strains of AK originating from Polish patients. Further investigations designed to foster a better understanding of the factors leading to an increase of AK observed in the past years in Poland may help to prevent or at least better cope with future cases.
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Taube MA, del Mar Cendra M, Elsahn A, Christodoulides M, Hossain P. Pattern recognition receptors in microbial keratitis. Eye (Lond) 2015; 29:1399-415. [PMID: 26160532 DOI: 10.1038/eye.2015.118] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Accepted: 05/31/2015] [Indexed: 12/12/2022] Open
Abstract
Microbial keratitis is a significant cause of global visual impairment and blindness. Corneal infection can be caused by a wide variety of pathogens, each of which exhibits a range of mechanisms by which the immune system is activated. The complexity of the immune response to corneal infection is only now beginning to be elucidated. Crucial to the cornea's defences are the pattern-recognition receptors: Toll-like and Nod-like receptors and the subsequent activation of inflammatory pathways. These inflammatory pathways include the inflammasome and can lead to significant tissue destruction and corneal damage, with the potential for resultant blindness. Understanding the immune mechanisms behind this tissue destruction may enable improved identification of therapeutic targets to aid development of more specific therapies for reducing corneal damage in infectious keratitis. This review summarises current knowledge of pattern-recognition receptors and their downstream pathways in response to the major keratitis-causing organisms and alludes to potential therapeutic approaches that could alleviate corneal blindness.
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Affiliation(s)
- M-A Taube
- Division of Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton, UK.,University Hospital Southampton NHS Foundation Trust, Southampton, UK
| | - M del Mar Cendra
- Division of Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton, UK
| | - A Elsahn
- Division of Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton, UK.,University Hospital Southampton NHS Foundation Trust, Southampton, UK
| | - M Christodoulides
- Division of Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton, UK
| | - P Hossain
- Division of Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton, UK.,University Hospital Southampton NHS Foundation Trust, Southampton, UK
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Yera H, Dupouy-Camet J, Jackson JW, Sriram R, Sweat S, Goldstein JM, Visvesvara GS. In vitro growth, cytopathic effects and clearance of monolayers by clinical isolates of Balamuthia mandrillaris in human skin cell cultures. Exp Parasitol 2015; 156:61-7. [PMID: 25980370 DOI: 10.1016/j.exppara.2015.05.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2014] [Revised: 04/25/2015] [Accepted: 05/11/2015] [Indexed: 10/23/2022]
Abstract
Balamuthia mandrillaris is a free-living ameba (FLA) that has been isolated or its DNA identified in soil, dust and water. It causes a fatal central nervous system infection in humans and animals. Although it is environmental as Acanthamoeba and Naegleria fowleri, the two other free-living amebae that also cause CNS infections in humans and other animals, Balamuthia does not feed on bacteria as the other FLA. In the laboratory, it can be grown on a variety of mammalian cell cultures. In this study we examined the ability of three different Balamuthia isolates to grow on several different human skin cell cultures including the WT/A keratinocyte cell cultures. A corneal isolate of Acanthamoeba castellanii was used for comparison.
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Affiliation(s)
- Hélène Yera
- Laboratory of Free-Living Amebae, Division of Foodborne, Waterborne and Environmental Diseases and Division of Scientific Resources, National Center for Environmental and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, 1600 Clifton Rd, Atlanta, GA 30333, USA; Laboratoire de Parasitologie Mycologie, Hôpital Cochin, Hôpitaux Universitaires Paris Centre, AP-HP, Faculté de Médecine Université Paris Descartes, 27 Rue Fbg Saint Jacques, 75014 Paris, France.
| | - Jean Dupouy-Camet
- Laboratoire de Parasitologie Mycologie, Hôpital Cochin, Hôpitaux Universitaires Paris Centre, AP-HP, Faculté de Médecine Université Paris Descartes, 27 Rue Fbg Saint Jacques, 75014 Paris, France
| | - Jonathan W Jackson
- Laboratory of Free-Living Amebae, Division of Foodborne, Waterborne and Environmental Diseases and Division of Scientific Resources, National Center for Environmental and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, 1600 Clifton Rd, Atlanta, GA 30333, USA
| | - Rama Sriram
- Laboratory of Free-Living Amebae, Division of Foodborne, Waterborne and Environmental Diseases and Division of Scientific Resources, National Center for Environmental and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, 1600 Clifton Rd, Atlanta, GA 30333, USA
| | - Stacey Sweat
- Scientific Products and Support Branch, Division of Scientific Resources, National Center for Environmental and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, 1600 Clifton Rd, Atlanta, GA 30333, USA
| | - Jason M Goldstein
- Scientific Products and Support Branch, Division of Scientific Resources, National Center for Environmental and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, 1600 Clifton Rd, Atlanta, GA 30333, USA
| | - Govinda S Visvesvara
- Laboratory of Free-Living Amebae, Division of Foodborne, Waterborne and Environmental Diseases and Division of Scientific Resources, National Center for Environmental and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, 1600 Clifton Rd, Atlanta, GA 30333, USA
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30
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Feng X, Zheng W, Wang Y, Zhao D, Jiang X, Lv S. A Rabbit Model ofAcanthamoebaKeratitis That Better Reflects the Natural Human Infection. Anat Rec (Hoboken) 2015; 298:1509-17. [DOI: 10.1002/ar.23154] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Accepted: 12/20/2014] [Indexed: 01/04/2023]
Affiliation(s)
- Xianmin Feng
- School of Laboratory Medicine, Jilin Medical College; Jilin China
| | - Wenyu Zheng
- Department of Hand Microsurgery; Central Hospital of Jilin City; Jilin China
| | - Yuehua Wang
- School of Laboratory Medicine, Jilin Medical College; Jilin China
- School of Basical Medicine, Jilin Medical College; Jilin China
| | - Donghai Zhao
- School of Basical Medicine, Jilin Medical College; Jilin China
| | - Xiaoming Jiang
- School of Laboratory Medicine, Jilin Medical College; Jilin China
| | - Shijie Lv
- School of Basical Medicine, Jilin Medical College; Jilin China
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31
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DREYFUSS JULIANAL, REGATIERI CAIOV, COELHO BRUNO, BARBOSA JOSÉB, FREITAS DENISEDE, NADER HELENAB, MARTINS JOÃOR. Altered hyaluronic acid content in tear fluid of patients with adenoviral conjunctivitis. ACTA ACUST UNITED AC 2015; 87:455-62. [DOI: 10.1590/0001-3765201520140122] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Accepted: 10/24/2014] [Indexed: 01/14/2023]
Abstract
The adenoviral conjunctivitis is one of the biggest causes of conjunctival infection in the world. Conjunctivitis causes relatively nonspecific symptoms, as hyperaemia and chemosis. Even after biomicroscopy, complex laboratory tests, such as viral culture, are necessary to identify the pathogen or its etiology. To contribute to the better understanding of the pathobiology of the adenoviral conjunctivitis, the tear fluids of patients with unilateral acute adenovirus conjunctivitis (UAAC), normal donors (control) and patients with allergic conjunctivitis were analyzed. Tear samples were collected with Schirmer strips from control, allergic conjunctivitis and UAAC patients, diagnosed by clinical signs. UAAC tears were tested positive in viral cultures. After the elution, HA was quantified using an ELISA-like fluorometric assay and the protein profile was determined by SDS-PAGE. A profound increase in the HA tear content in UAAC patients was found when compared to control and ALC. This HA increase in UAAC tears remarkably was not observed in tears from contralateral eyes without clinical signs, nor in allergic conjunctivitis. In addition a distinct profile of UAAC tear proteins was observed in patients with UAAC. The quantification of HA in the tear fluid is a rapid, sensitive and specific test. This molecule might be a biomarker candidate for acute conjunctivitis.
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Affiliation(s)
- JULIANA L. DREYFUSS
- Universidade Federal de São Paulo, Brasil; Universidade Federal de São Paulo, Brasil
| | - CAIO V. REGATIERI
- Universidade Federal de São Paulo, Brasil; Universidade Federal de São Paulo, Brasil; New England Eye Center, USA
| | | | | | | | | | - JOÃO R. MARTINS
- Universidade Federal de São Paulo, Brasil; Universidade Federal de São Paulo, Brasil
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Abstract
BACKGROUND Acanthamoeba are microscopic, free-living, single-celled organisms which can infect the eye and lead to Acanthamoeba keratitis (AK). AK can result in loss of vision in the infected eye or loss of eye itself; however, there are no formal guidelines or standards of care for the treatment of AK. OBJECTIVES To evaluate the relative effectiveness and safety of medical therapy for the treatment of AK. SEARCH METHODS We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (2015, Issue 1), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to January 2015), EMBASE (January 1980 to January 2015), PubMed (1948 to January 2015), Latin American and Caribbean Health Sciences Literature Database (LILACS) (1982 to January 2015), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrials.gov) and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic search for trials. We last searched the electronic databases on 9 January 2015. SELECTION CRITERIA We included randomized controlled trials (RCTs) of medical therapy for AK, regardless of the participants' age, sex, or etiology of disease. We included studies that compared either anti-amoeba therapy (drugs used alone or in combination with other medical therapies) with no anti-amoeba therapy or one anti-amoeba therapy with another anti-amoeba therapy. DATA COLLECTION AND ANALYSIS Two authors independently screened search results and full-text reports, assessed risk of bias, and abstracted data. We used standard methodological procedures as set forth by the Cochrane Collaboration. MAIN RESULTS We included one RCT (56 eyes of 55 participants) in this review. The study compared two types of topical biguanides for the treatment of AK: chlorhexidine 0.02% and polyhexamethylene biguanide (PHMB) 0.02%. All participants were contact lens wearers with a median age of 31 years. Treatment duration ranged from 51 to 145 days. The study, conducted in the UK, was well-designed and had low risk of bias overall.Outcome data were available for 51 (91%) of 56 eyes. Follow-up times for outcome measurements in the study were not reported. Resolution of infection, defined as control of ocular inflammation, relief of pain and photosensitivity, and recovery of vision, was 86% in the chlorhexidine group compared with 78% in the PHMB group (relative risk (RR) 1.10, 95% confidence intervals (CI) 0.84 to 1.42). In the chlorhexidine group, 20 of 28 eyes (71%) had better visual acuity compared with 13 of 23 eyes (57%) in the PHMB group at final follow-up (RR 1.26, 95% CI 0.82 to 1.94). Five participants required therapeutic keratoplasty: 2 in the chlorhexidine group compared with 3 in the PHMB group (RR 0.55, 95% CI 0.10 to 3.00). No serious adverse event related to drug toxicity was observed in the study. AUTHORS' CONCLUSIONS There is insufficient evidence to evaluate the relative effectiveness and safety of medical therapy for the treatment of AK. Results from the one included study yielded no difference with respect to outcomes reported between chlorhexidine and PHMB. However, the sample size was inadequate to detect clinically meaningful differences between the two groups as indicated by the wide confidence intervals of effect estimates.
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Affiliation(s)
- Majed Alkharashi
- Department of Ophthalmology, King Saud University, Riyadh, Saudi Arabia.
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Ji WT, Hsu BM, Chang TY, Hsu TK, Kao PM, Huang KH, Tsai SF, Huang YL, Fan CW. Surveillance and evaluation of the infection risk of free-living amoebae and Legionella in different aquatic environments. THE SCIENCE OF THE TOTAL ENVIRONMENT 2014; 499:212-219. [PMID: 25192927 DOI: 10.1016/j.scitotenv.2014.07.116] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2014] [Revised: 07/29/2014] [Accepted: 07/30/2014] [Indexed: 06/03/2023]
Abstract
Free-living amoebae (FLA) are ubiquitous in various aquatic environments. Several amoebae species are pathogenic and host other pathogens such as Legionella, but the presence of FLA and its parasites as well as the related infection risk are not well known. In this study, the presence of pathogenic FLA and Legionella in various water bodies was investigated. Water samples were collected from a river, intake areas of drinking water treatment plants, and recreational hot spring complexes in central and southern Taiwan. A total of 140 water samples were tested for the presence of Acanthamoeba spp., Naegleria spp., Vermamoeba vermiformis, and Legionella. In addition, phylogenetic characteristics and water quality parameters were also assessed. The pathogenic genotypes of FLA included Acanthamoeba T4 and Naegleria australiensis, and both were abundant in the hot spring water. In contrast, Legionella pneumophila was detected in different aquatic environments. Among the FLA assessed, V. vermiformis was most likely to coexist with Legionella spp. The total bacteria level was associated with the presence of FLA and Legionella especially in hot spring water. Taken together, FLA contamination in recreational hot springs and drinking water source warrants more attention on potential legionellosis and amoebae infections.
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Affiliation(s)
- Wen-Tsai Ji
- Department of Earth and Environmental Sciences, National Chung Cheng University, Chiayi, Taiwan, ROC
| | - Bing-Mu Hsu
- Department of Earth and Environmental Sciences, National Chung Cheng University, Chiayi, Taiwan, ROC.
| | - Tien-Yu Chang
- Department of Radiology, Taipei Medical University Hospital, 252 Wu Hsing Street, Taipei, Taiwan, ROC
| | - Tsui-Kang Hsu
- Department of Ophthalmology, Cheng Hsin General Hospital, Taipei, Taiwan, ROC; Department of Life Science, Institute of Molecular Biology and Institute of Biomedical Science, National Chung Cheng University, Min-Hsiung, Chiayi, Taiwan, ROC
| | - Po-Min Kao
- Department of Earth and Environmental Sciences, National Chung Cheng University, Chiayi, Taiwan, ROC
| | - Kuan-Hao Huang
- Department of Life Science, Institute of Molecular Biology and Institute of Biomedical Science, National Chung Cheng University, Min-Hsiung, Chiayi, Taiwan, ROC
| | - Shiou-Feng Tsai
- Department of Earth and Environmental Sciences, National Chung Cheng University, Chiayi, Taiwan, ROC
| | - Yu-Li Huang
- Department of Safety Health and Environmental Engineering, National Kaohsiung First University of Science and Technology, Kaohsiung, Taiwan, ROC
| | - Cheng-Wei Fan
- Department of Earth and Environmental Sciences, National Chung Cheng University, Chiayi, Taiwan, ROC
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Bouheraoua N, Labbé A, Chaumeil C, Liang Q, Laroche L, Borderie V. [Acanthamoeba keratitis]. J Fr Ophtalmol 2014; 37:640-52. [PMID: 25169145 DOI: 10.1016/j.jfo.2014.05.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2014] [Revised: 05/25/2014] [Accepted: 05/26/2014] [Indexed: 11/24/2022]
Abstract
Early diagnosis and appropriate therapy are key elements for a good prognosis in Acanthamoeba keratitis (AK). AK should be considered in any case of corneal trauma complicated by exposure to soil or contaminated water, and in all contact lens (CL) wearers. A presumptive diagnosis of AK can be made clinically and with in vivo confocal microscopy, although a definitive diagnosis requires identification of Acanthamoeba on direct scraping, histology, or identification of Acanthamoeba DNA by polymerase chain reaction (PCR). We use cysticidal drugs for treating AK because encysted forms are more resistant than trophozoites to treatment. The treatment protocol used a biguanide (PHMB 0.02% or chlorhexidine 0.02%) and a diamidine (propamidine 0.1% or hexamidine 0.1%). New diagnostic modalities and more specific topical anti-amoebic treatments would substantially benefit patients with AK.
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Affiliation(s)
- N Bouheraoua
- Service d'ophtalmologie 5, Centre hospitalier national d'ophtalmologie des Quinze-Vingts, 28, rue de Charenton, 75012 Paris, France; Inserm, U968, UPMC Paris VI, UMR S 968, CNRS, UMR 7210, institut de la vision, 17, rue Moreau, 75012 Paris, France.
| | - A Labbé
- Inserm, U968, UPMC Paris VI, UMR S 968, CNRS, UMR 7210, institut de la vision, 17, rue Moreau, 75012 Paris, France; Service d'ophtalmologie 3, Centre hospitalier national d'ophtalmologie des Quinze-Vingts, 28, rue de Charenton, 75012 Paris, France; Service d'ophtalmologie, hôpital Ambroise-Paré, AP-HP, DHU View maintain, 9, avenue Charles-de-Gaulle, 92100 Boulogne-Billancourt, France
| | - C Chaumeil
- Service de biologie médicale, Centre hospitalier national d'ophtalmologie des Quinze-Vingts, 28, rue de Charenton, 75012 Paris, France
| | - Q Liang
- Beijing Institute of Ophthalmology, Beijing TongRen Eye Center, Beijing TongRen Hospital, Capital Medical University, Beijing, Chine
| | - L Laroche
- Service d'ophtalmologie 5, Centre hospitalier national d'ophtalmologie des Quinze-Vingts, 28, rue de Charenton, 75012 Paris, France; Inserm, U968, UPMC Paris VI, UMR S 968, CNRS, UMR 7210, institut de la vision, 17, rue Moreau, 75012 Paris, France
| | - V Borderie
- Service d'ophtalmologie 5, Centre hospitalier national d'ophtalmologie des Quinze-Vingts, 28, rue de Charenton, 75012 Paris, France; Inserm, U968, UPMC Paris VI, UMR S 968, CNRS, UMR 7210, institut de la vision, 17, rue Moreau, 75012 Paris, France
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35
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Wan KHN, Jhanji V, Young AL. Orthokeratology lens related infections. World J Ophthalmol 2014; 4:63-70. [DOI: 10.5318/wjo.v4.i3.63] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Revised: 05/21/2014] [Accepted: 06/27/2014] [Indexed: 02/06/2023] Open
Abstract
Orthokeratology is a reversible technique that temporarily changes the curvature of the cornea with the aim of addressing refractive errors. The United States Food and Drug Administration (FDA) granted approval for using reverse geometry contact lenses to correct myopia without any age restriction. Information from the pre-market applications to the FDA was rated as level II evidence. Another unapproved use of overnight orthokeratology is for the prevention of myopic progression. Although orthokeratology is advocated to reduce myopic progression, there are limited long-term studies with substantial evidence of its benefits. Much of this evidence comes from non-robust experimental studies using historical or self-selected controls with relative high dropout rates. Although some positive results have been published in temporarily reducing the myopic refractive error and its progression, the use of these lenses can be associated with serious complications such as microbial keratitis. Microbial keratitis is a potentially vision-threatening adverse response associated with contact lens wear. In fact, contact lens wear has been shown to be the predominant risk factor of microbial keratitis in some developed countries. Most of the published cases on overnight orthokeratology related microbial keratitis occurred in children or adolescents. Parents considering orthokeratology must make an informed decision about its temporary benefit and its potential for permanent loss of vision. The ophthalmic community should be reminded of the potential complications of orthokeratology.
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Pumidonming W, Koehsler M, Leitsch D, Walochnik J. Protein profiles and immunoreactivities of Acanthamoeba morphological groups and genotypes. Exp Parasitol 2014; 145 Suppl:S50-6. [PMID: 24858925 DOI: 10.1016/j.exppara.2014.05.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2014] [Revised: 04/25/2014] [Accepted: 05/07/2014] [Indexed: 12/20/2022]
Abstract
Acanthamoeba is a free-living protozoan found in a wide variety of habitats. A classification of Acanthamoeba into currently eighteen genotypes (T1-T18) has been established, however, data on differences between genotypes on the protein level are scarce. The aim of this study was to compare protein and immunoreactivity profiles of Acanthamoeba genotypes. Thirteen strains, both clinical and non-clinical, from genotypes T4, T5, T6, T7, T9, T11 and T12, representing three morphological groups, were investigated for their protein profiles and IgG, IgM and IgA immunoreactivities. It was shown that protein and immunoreactivity profiles of Acanthamoeba genotypes T4, T5, T6, T7, T9, T11 and T12 are clearly distinct from each other, but the banding patterns correlate to the morphological groups. Normal human sera revealed anti-Acanthamoeba antibodies against isolates of all investigated genotypes, interestingly, however only very weak IgM and virtually no IgA immunoreactivity with T7 and T9, both representing morphological group I. The strongest IgG, IgM and IgA immunoreactivities were observed for genotypes T4, T5 and T6. Differences of both, protein and immunological patterns, between cytopathic and non-cytopathic strains, particularly within genotype T4, were not at the level of banding patterns, but rather in expression levels.
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Affiliation(s)
- Wilawan Pumidonming
- Institute of Specific Prophylaxis and Tropical Medicine, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Kinderspitalgasse 15, 1090 Vienna, Austria
| | - Martina Koehsler
- Institute of Specific Prophylaxis and Tropical Medicine, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Kinderspitalgasse 15, 1090 Vienna, Austria
| | - David Leitsch
- Institute of Specific Prophylaxis and Tropical Medicine, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Kinderspitalgasse 15, 1090 Vienna, Austria
| | - Julia Walochnik
- Institute of Specific Prophylaxis and Tropical Medicine, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Kinderspitalgasse 15, 1090 Vienna, Austria.
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The first genotype determination of Acanthamoeba potential threat to human health, isolated from natural water reservoirs in Poland. Parasitol Res 2014; 113:2693-9. [PMID: 24770720 PMCID: PMC4058056 DOI: 10.1007/s00436-014-3925-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2014] [Accepted: 04/16/2014] [Indexed: 11/20/2022]
Abstract
Different species of amoebae belonging to the genus Acanthamoeba are widely distributed in many parts of the world and known as free-living organisms. Some strains of the protozoans may exist as parasites and cause risk to human health as causative agents of serious human diseases. Currently, in Poland, there is no sufficient information about the distribution of Acanthamoeba strains and their genotypes in the environment. Therefore, 20 environmental surface water samples were collected from different sites located at five water reservoirs in Gdynia, Sopot, and Gdańsk (northern Poland). The material was cultured to obtain Acanthamoeba isolates that were then specifically analyzed with both PCR and real-time PCR assays. Of the 20 samples examined, Acanthamoeba DNA was found in 13 samples tested with the use of real-time PCR; in 10 of them, DNA of the amoeba was also detected using PCR technique. The comparison with sequences available in the GenBank confirmed that the PCR products are fragments of Acanthamoeba 18S rRNA gene and that isolates represent T4 genotype, known as the most common strains related to AK cases. This is the first investigation in Poland describing Acanthamoeba detection in environmental water samples with molecular techniques and genotyping. The results indicate that surface water in Poland may be a source of acanthamoebic strains potentially pathogenic for humans.
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Non-contact lens use-related Acanthamoeba keratitis in southern Turkey: evaluation of risk factors and clinical features. Eur J Ophthalmol 2013; 24:164-72. [PMID: 24030538 DOI: 10.5301/ejo.5000357] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/02/2013] [Indexed: 11/20/2022]
Abstract
PURPOSE To assess the diagnostic methods, risk factors, and clinical features of Acanthamoeba keratitis cases in patients who do not wear contact lenses. METHODS Medical records of 26 consecutive patients with non-contact lens-related Acanthamoeba keratitis, who were followed up at the tertiary eye care center between May 2010 and May 2012, were analyzed. Laboratory, demographic, and clinical findings were evaluated pertaining to the patients. RESULTS Twenty-six non-contact lens-related Acanthamoeba keratitis cases were included in the study. The main risk factors were trauma (group 1, n = 13 patients) and ocular surface disease (group 2, n = 12 patients). One patient had both of the risk factors mentioned above. Overall test results showed that Acanthamoeba positivity rates were 15.3% for direct microscopy, 46.1% for culture, 92.3% for conventional polymerase chain reaction (PCR), and 100% for real-time PCR. The rates of full-thickness corneal involvement and ring-shaped infiltrations were higher in group 2, whereas superficial keratitis and radial keratoneuritis were higher in group 1. The final visual acuities were significantly better in group 1 than group 2 (p<0.025). CONCLUSIONS This study is the first regional report from Turkey about Acanthamoeba keratitis in non-contact lens users. A majority of cases admitted to a tertiary eye care center were related to trauma or ocular surface disease. Physician suspicion is critically important for the timely diagnosis of these cases. At this point, molecular diagnostic tests (PCR or real-time PCR) seem to support the clinical diagnosis of Acanthamoeba keratitis with the help of fast and reliable results.
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Makdoumi K, Bäckman A, Mortensen J, Magnuson A, Crafoord S. Comparison of UVA- and UVA/riboflavin-induced growth inhibition of Acanthamoeba castellanii. Graefes Arch Clin Exp Ophthalmol 2012; 251:509-14. [PMID: 23079692 DOI: 10.1007/s00417-012-2176-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2012] [Revised: 09/25/2012] [Accepted: 10/02/2012] [Indexed: 11/28/2022] Open
Abstract
PURPOSE To investigate whether ultraviolet light (UVA) at 365 nm can inhibit/eliminate Acanthamoeba growth and if riboflavin would potentiate such an association. METHODS Acanthamoeba castellanii in a fluid medium with a concentration of approximately 1.7 × 10(4) protozoa/ml were prepared with (0.01 %) and without riboflavin. Exposure of UVA (dose 5.475 J/cm(2)) took place twice, with each illumination period followed by culturing of 10 μl in peptone yeast-extract glucose (PYG) medium for 7 days. Every suspension prepared had a non-exposed control solution. Determination of Acanthamoeba was conducted daily, by count in Burker chamber days 4 through 7 after exposure. Statistical analysis was done by repeated-measurement ANOVA and post-hoc analysis for unpaired samples. RESULTS The exposure of ultraviolet light resulted in an inhibited growth of Acanthamoeba compared to the non-exposed solutions, with a statistically significant reduction over time (p = 0.0003). The addition of riboflavin did not amplify the effect, and there were no tendencies for an interaction effect between UVA and riboflavin. CONCLUSIONS The antiprotozoal effect of the UVA wavelength, utilized in CXL, is solely mediated by ultraviolet light, and riboflavin does not seem to amplify the antimicrobial efficacy.
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Affiliation(s)
- Karim Makdoumi
- Department of Ophthalmology, Örebro University Hospital, 701 85, Örebro, Sweden.
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Abstract
Acanthamoeba keratitis (AK) is a serious infection of the cornea. At present, diagnosis of the disease is not straightforward and treatment is very demanding. While contact lens wear is the leading risk factor for A K, Acanthamoeba parasites are increasingly recognized as an important cause of keratitis in non-contact lens wearers. The first critical step in the pathogenesis of infection is the adhesion of the microbe to the surface of the host tissues. Acanthamoebae express a major virulence protein, the mannose-binding protein (MBP), which mediates the adhesion of amoebae to the surface of the cornea. The MBP is a transmembrane protein with characteristics of a typical cell surface receptor. Subsequent to the MBP-mediated adhesion to host cells, the amoebae produce a contact-dependent metalloproteinase and several contact-independent serine proteinases. These proteinases work in concert to produce a potent cytopathic effect (CPE ) involving killing of the host cells, degradation of epithelial basement membrane and underlying stromal matrix, and penetration into the deeper layers of the cornea. In the hamster animal model, oral immunization with the recombinant MBP protects against AK, and this protection is associated with an increased level of anti-MBP IgA in tears of protected animals. Normal human tear fluid contains IgA antibodies against Acanthamoeba MBP that is likely to provide protection by inhibiting the adhesion of parasites to host cells. Indeed, in in vitro CPE assays, even a low concentration of tears (10 microL of undiluted tears per milliliter of media) almost completely inhibits Acanthamoeba-induced CPE . In addition to adherence-inhibiting, IgA-mediated protection, human tears also contain IgA-independent factors that provide protection against Acanthamoeba-induced CPE by inhibiting the activity of cytotoxic proteinases. Characterization of the CPE-inhibitory factors of human tears should lead to a better understanding of the mechanism by which the tissues of the host resist the infection and also help decode circumstances that predispose to Acanthamoeba infections.
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Affiliation(s)
- Noorjahan Panjwani
- Departments of Ophthalmology and Biochemistry, The New England Eye Center, Tufts University School of Medicine, Boston, Massachusetts, USA.
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Binding to complement factors and activation of the alternative pathway by Acanthamoeba. Immunobiology 2010; 216:225-33. [PMID: 20627448 DOI: 10.1016/j.imbio.2010.05.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2010] [Revised: 03/30/2010] [Accepted: 05/02/2010] [Indexed: 11/22/2022]
Abstract
Acanthamoeba can cause severe ocular and cerebral diseases in healthy and immunocompromised individuals, respectively. Activation of complement appears to play an important role in host defence against infection. The exact mechanism, however, is still unclear. The aim of the present study was to investigate the effect of normal human serum (NHS) and normal mouse serum (NMS) on Acanthamoeba trophozoites, the binding of different complement factors to Acanthamoeba and the activation of the complement system. Moreover, we aimed to work out any possible differences between different strains of Acanthamoeba. A virulent T4 strain, a non-virulent T4 strain and a virulent T6 strain were included in the study. It was shown that NHS, but not NMS clearly has amoebicidal properties. After 5min of incubation with NHS, amoebae showed plasma membrane disruption and extrusion of intracellular components. Cells were completely destroyed within 60min of incubation in NHS but stayed intact after incubation in heat-inactivated serum. The binding of human C3 and C9 to amoebae was established by immunoblotting. Although incubation with mouse serum did not result in lysis of Acanthamoeba trophozoites an immunofluorescence assay (IFA) demonstrated a strong deposition of mouse complement factor C3 activation products, moderate binding of C1q, but no binding of MBL-A and MBL-C. EDTA inhibited the binding of C3 to acanthamoebae. Binding of amoebae to C3b was observed with sera from C1qa-/- and MBL-A/C-/- mice, but not with serum from Bf/C2-/- mice demonstrating an activation of complement via the alternative pathway. There were no significant differences between the three Acanthamoeba strains investigated. Altogether, our results prove that NHS is amoebolytic and that Acanthamoeba binds to C3 and C9 and activates the complement system via the alternative pathway.
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Magliano AC, da Silva FM, Teixeira MM, Alfieri SC. Genotyping, physiological features and proteolytic activities of a potentially pathogenic Acanthamoeba sp. isolated from tap water in Brazil. Exp Parasitol 2009; 123:231-5. [DOI: 10.1016/j.exppara.2009.07.006] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2009] [Revised: 06/23/2009] [Accepted: 07/21/2009] [Indexed: 11/26/2022]
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Dart JKG, Saw VPJ, Kilvington S. Acanthamoeba keratitis: diagnosis and treatment update 2009. Am J Ophthalmol 2009; 148:487-499.e2. [PMID: 19660733 DOI: 10.1016/j.ajo.2009.06.009] [Citation(s) in RCA: 311] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2009] [Revised: 05/31/2009] [Accepted: 06/01/2009] [Indexed: 11/16/2022]
Abstract
PURPOSE To describe the current management of Acanthamoeba keratitis (AK). DESIGN A perspective based on the literature and author experience. RESULTS Early diagnosis and appropriate therapy are key to a good prognosis. A provisional diagnosis of AK can be made using the clinical features and confocal microscopy, although a definitive diagnosis requires culture, histology, or identification of Acanthamoeba deoxyribonucleic acid by polymerase chain reaction. Routine use of tissue diagnosis is recommended, particularly for patients unresponsive to treatment for AK. Topical biguanides are the only effective therapy for the resistant encysted form of the organism in vitro, if not always in vivo. None of the other drugs that have been used meet the requirements of consistent cysticidal activity and may have no therapeutic role. The use of topical steroids is controversial, but probably beneficial, for the management of severe corneal inflammatory complications that have not responded to topical biguanides alone. The scleritis associated with AK is rarely associated with extracorneal invasion and usually responds to systemic anti-inflammatory treatment combined with topical biguanides. Therapeutic keratoplasty retains a role for therapy of some severe complications of AK but not for initial treatment. With modern management, 90% of patients can expect to retain visual acuity of 6/12 or better and fewer than 2% become blind, although treatment may take 6 months or more. CONCLUSIONS Better understanding of the pathogenesis of the extracorneal complications, the availability of polymerase chain reaction for tissue diagnosis, and effective licensed topical anti-amoebics would substantially benefit patients with AK.
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Affiliation(s)
- John K G Dart
- Corneal and External Disease Service, Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom.
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Brindley N, Matin A, Khan NA. Acanthamoeba castellanii: high antibody prevalence in racially and ethnically diverse populations. Exp Parasitol 2008; 121:254-6. [PMID: 19071116 DOI: 10.1016/j.exppara.2008.11.009] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2008] [Revised: 11/17/2008] [Accepted: 11/23/2008] [Indexed: 10/21/2022]
Abstract
Acanthamoeba is an opportunistic protozoan pathogen that can produce keratitis and rare but fatal encephalitis. In the present study, we examined secretory IgA antibody to Acanthamoeba castellanii of the T4 genotype in mucosal secretions from 114 individuals of 37 countries, inhabitants and/or visitors, aged 16-65 years in London, UK. Acanthamoeba antibody prevalence rate was more than 85%, without any significant differences between males (86.2%) and females (89.2%). Some epidemiological factors contributing to the high prevalence of antibody to Acanthamoeba in surveyed population are discussed further.
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Safety of Overnight Orthokeratology for Myopia. Ophthalmology 2008; 115:2301-2313.e1. [DOI: 10.1016/j.ophtha.2008.06.034] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2008] [Accepted: 06/26/2008] [Indexed: 11/19/2022] Open
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Sahu PS, Parija SC, Sahu PK. Tear IgA-ELISA: a novel and sensitive method for diagnosis of ophthalmic cysticercosis. Acta Trop 2008; 106:168-74. [PMID: 18462701 DOI: 10.1016/j.actatropica.2008.03.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2007] [Revised: 03/09/2008] [Accepted: 03/11/2008] [Indexed: 11/29/2022]
Abstract
For the first time, presence of locally secreted specific IgA antibodies in tear specimen from human with ophthalmic cysticercosis is documented in the present study. The ELISA using Taenia solium metacestode excretory secretory (ES) antigen demonstrated a diagnostic level of IgA antibodies in tears with 100% sensitivity (6 out of 6 confirmed cases of ophthalmic cysticercosis) whereas, 25 of 34 (73.52%) clinically suspected cases were diagnosed positive. The ELISA using T. solium metacestode somatic antigen detected a diagnostic titre of IgA antibody in tears with a sensitivity of 50% (3 out of 6 confirmed cases). The specificity of the tear IgAELISA using T. solium metacestode somatic and ES antigens is observed to be 94.87% and 92.3%, respectively. Overall in tears, the ELISA using T. solium metacestode ES antigens for detection of IgA antibodies shows a higher diagnostic efficiency (93.33%) compared to that using T. solium metacestode somatic antigen (88.88%). The sensitivities of the ELISA for detection of IgA antibodies in tears is observed to be higher than that for detection of IgG antibodies in serum using either somatic or ES antigens of the parasite.
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Affiliation(s)
- Priyadarshi S Sahu
- Department of Microbiology, Jawaharlal Institute of Postgraduate Medical Education and Research, Pondicherry, India.
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Alsam S, Ryoul Jeong S, Dudley R, Ahmed Khan N. Role of human tear fluid in Acanthamoeba interactions with the human corneal epithelial cells. Int J Med Microbiol 2008; 298:329-36. [DOI: 10.1016/j.ijmm.2007.05.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2006] [Revised: 05/29/2007] [Accepted: 05/29/2007] [Indexed: 11/16/2022] Open
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Acanthamoeba keratitis: persistent organisms without inflammation after 1 year of topical chlorhexidine. Cornea 2008; 27:246-8. [PMID: 18216589 DOI: 10.1097/ico.0b013e31815b82a2] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE To report a non-contact lens wearer with persistent Acanthamoeba organisms in the cornea after being treated with medical therapy that included topical chlorhexidine as 1 agent for 1 year. METHODS A 53-year-old man with Acanthamoeba keratitis was treated with medical therapy for >1 year, followed by a penetrating keratoplasty. RESULTS Histopathologic examination of the keratoplasty specimen revealed viable-appearing Acanthamoeba cysts and trophozoites within the deep corneal stroma in a focus of corneal scarring. CONCLUSIONS The use of chlorhexidine as 1 agent in the medical management of Acanthamoeba keratitis may not eradicate the organisms.
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