Rapid Identification of Ocular Fungal and Amoebic Pathogens
Eduardo C. Alfonso, Darlene Miller, Mara Diaz and Jack W. Fell
Problem
Currently, diagnosis of fungal eye infections is a clinical and therapeutic challenge. Typically such infections are diagnosed as bacterial because of similar clinical features. Fungal involvement is usually suspected only after antibiotic therapy has failed. Since eye infections progress rapidly and can have devastating and irreversible effects, failure to recognize the causative agent and apply appropriate therapy has serious consequences.
Solution
To address the unmet clinical need, a quick DNA test using bead array technology for the rapid identification of fungal and ameobic pathogens in infected ocular tissues is being developed. The assay will combine the specificity and reliability of nucleic acid hybridization analysis, with the speed and sensitivity of Luminex instrumentation. The bead suspension array allows combination of up to 100 different unique fluorescence microspheres, with the capability to identify up to 100 pathogenic species per well in a 96 well format at an estimated rate of 0.47 min.
Competitive Advantage
High speed and high sensitivity for rapid and accurate diagnosis
Inexpensive
Versatile as a variety of probes can be added or subtracted to create different arrays that can be employed in a wide variety of applications
Applications
The technology could potentially be used to target all medically important ocular fungal pathogens for direct detection from clinical samples. Contrary to gene chips, the present technology is inexpensive and versatile, as a variety of probes can be added or subtracted to create different arrays that can be employed in a wide variety of applications. The technology will help to reduce morbidity by allowing rapid and accurate medical treatment of fungal eye infections. This multiplex, DNA bead suspension array can be expanded to include other ocular disease microorganisms, particularly bacteria and protozoans. The technology can also be employed in relevant areas of public health, bioterrorism, food safety and the environment.
Patent Status
International Patent Application No. PCT/US10/32030 filed April 27, 2010.
Licensing Opportunity
The University of Miami is seeking collaborative research and licensing options.
About the Inventors
Eduardo C. Alfonso, M.D., is the Interim Chairman of the Department of Ophthalmology, Director of the Bascom Palmer Eye Institute and Medical Director of the Anne Bates Leach Eye Hospital, at the Miller School of Medicine, University of Miami. A cornea specialist, Dr. Alfonso has a special interest in corneal transplants. He is an internationally known expert on ocular infectious diseases. In 2006 he documented an increase in the incidence of an aggressive form of fungal corneal infection that was related to soft contact lens use. His findings drew considerable media attention throughout the world and significantly reduced the number of new infections.
Jack Fell, Ph.D., is a Professor of Microbiology at the Rosenstiel School of Marine and Atmospheric Science, University of Miami. Dr. Fell's research interests include studies on the role of fungi in marine food webs and adapting molecular systematics for rapid identification of marine and terrestrial microbes using technologies such as suspension arrays and electrochemistry. He, and co-inventor Dr. Mara Diaz, developed several high throughput techniques (patents pending) for rapid detection of various pathogens which have been licensed to industry for commercial exploitation.
Mara Diaz, Ph.D., is an Associate Scientist in the Division of Marine Biology and Fisheries, Rosenstiel School of Marine and Atmospheric Science.
Darlene Miller, D.H.Sc., is an Assistant Research Professor and Scientific Director of the Ocular Microbiology Laboratory at Bascom Palmer Eye Institute.
Selected References
Alfonso EC, Genotypic identification of Fusarium species from ocular sources: comparison to morphologic classification and antifungal sensitivity testing (an AOS thesis). Trans Am Ophthalmol Soc 2008; 106: 227-239.
Alfonso EC, Cantu-Dibildox J, Munir WM, et al. Insurgence of Fusarium keratitis associated with contact lens wear. Arch Ophthalmol 2006; 124: 941-7.
Ritterband DC, Seedor JA, Shah MK, et al. Fungal keratitis at the New York Eye and Ear Infirmary. Cornea 2006; 25: 264-7.
Dursun D, Fernandez V, Miller D, Alfonso EC. Advanced Fusarium keratitis progressing to endophthalmitis. Cornea 2003; 22: 300-3.
Tanure MAG, Cohen EJ, Sudesh S, et al. Spectrum of fungal keratitis at Wills Eye Hospital, Philadelphia, Pennsylvania. Cornea 2000; 19: 307-12.
Rosa RH Jr, Miller D, Alfonso EC. The changing spectrum of fungal keratitis in south Florida. Ophthalmol 1994; 101: 1005-1013.
Koidou-Tsiligianni A, Alfonso E, Forster RK. Ulcerative keratitis associated with contact lens wear. Am J Ophthalmol 1989; 108: 64-67.
Alfonso EC, Mandelbaum S, Fox MJ, Forster RK. Ulcerative keratitis associated with contact lens wear. Am J Ophthalmol 1986; 101: 429-433.
Liesegang TJ, Forster RK. Spectrum of microbial keratitis in South Florida. Am J Ophthalmol 1980; 90: 38-47.
