1
|
Bispo PJM, Belanger N, Li A, Liu R, Susarla G, Chan W, Chodosh J, Gilmore MS, Sobrin L. An All-in-One Highly Multiplexed Diagnostic Assay for Rapid, Sensitive, and Comprehensive Detection of Intraocular Pathogens. Am J Ophthalmol 2023; 250:82-94. [PMID: 36709019 PMCID: PMC10760444 DOI: 10.1016/j.ajo.2023.01.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 01/08/2023] [Accepted: 01/17/2023] [Indexed: 01/27/2023]
Abstract
PURPOSE Intraocular infections are sight-threatening conditions that can lead to vision loss. Rapid identification of the etiologies plays a key role in early initiation of effective therapy to save vision. However, current diagnostic modalities are time consuming and lack sensitivity and inclusiveness. We present here a newly developed comprehensive ocular panel designed to improve diagnostic yields and provide a tool for rapid and sensitive pathogen detection. DESIGN Experimental laboratory investigation. METHODS A panel containing 46 pathogens and 2 resistance/virulence markers that are commonly detected in intraocular infections was developed. Genomic targets were scrutinized for stretches predicted to be specific for a particular species while being conserved across different strains. A set of primers for sample enrichment, and two 50mer NanoString compatible probes were then designed for each target. Probe-target hybrids were detected and quantified using the NanoString nCounter SPRINT Profiler. Diagnostic feasibility was assessed in a pilot clinical study testing samples from infectious retinitis (n = 15) and endophthalmitis (n = 12) patients, for which the etiologies were confirmed by polymerase chain reaction (PCR) or culture. RESULTS Analytical studies demonstrated highly sensitive detection of a broad spectrum of pathogens, including bacteria, viruses, and parasites, with limits of detection being as low as 2.5 femtograms per reaction. We also found excellent target specificity, with minimal cross-reactivity detected. The custom-designed NanoString ocular panel correctly identified the causative agent from all clinical specimens positive for a variety of pathogens. CONCLUSION This highly multiplexed panel for pathogen detection offers a sensitive, comprehensive, and uniform assay run directly on ocular fluids that could significantly improve diagnostics of sight-threatening intraocular infections.
Collapse
Affiliation(s)
- Paulo J M Bispo
- From the Department of Ophthalmology (P.J.M.B., N.B., A.L., R.L., G.S., W.C., J.C., M.S.G., L.S.), Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts, USA; Infectious Disease Institute (P.J.M.B., N.B., J.C., M.S.G., L.S.), Harvard Medical School, Boston, Massachusetts, USA.
| | - Nicole Belanger
- From the Department of Ophthalmology (P.J.M.B., N.B., A.L., R.L., G.S., W.C., J.C., M.S.G., L.S.), Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts, USA; Infectious Disease Institute (P.J.M.B., N.B., J.C., M.S.G., L.S.), Harvard Medical School, Boston, Massachusetts, USA
| | - Ashley Li
- From the Department of Ophthalmology (P.J.M.B., N.B., A.L., R.L., G.S., W.C., J.C., M.S.G., L.S.), Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts, USA
| | - Renee Liu
- From the Department of Ophthalmology (P.J.M.B., N.B., A.L., R.L., G.S., W.C., J.C., M.S.G., L.S.), Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts, USA
| | - Gayatri Susarla
- From the Department of Ophthalmology (P.J.M.B., N.B., A.L., R.L., G.S., W.C., J.C., M.S.G., L.S.), Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts, USA
| | - Weilin Chan
- From the Department of Ophthalmology (P.J.M.B., N.B., A.L., R.L., G.S., W.C., J.C., M.S.G., L.S.), Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts, USA
| | - James Chodosh
- From the Department of Ophthalmology (P.J.M.B., N.B., A.L., R.L., G.S., W.C., J.C., M.S.G., L.S.), Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts, USA; Infectious Disease Institute (P.J.M.B., N.B., J.C., M.S.G., L.S.), Harvard Medical School, Boston, Massachusetts, USA
| | - Michael S Gilmore
- From the Department of Ophthalmology (P.J.M.B., N.B., A.L., R.L., G.S., W.C., J.C., M.S.G., L.S.), Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts, USA; Infectious Disease Institute (P.J.M.B., N.B., J.C., M.S.G., L.S.), Harvard Medical School, Boston, Massachusetts, USA; Department of Microbiology and Immunobiology (M.S.G.), Harvard Medical School, Boston, Massachusetts, USA
| | - Lucia Sobrin
- From the Department of Ophthalmology (P.J.M.B., N.B., A.L., R.L., G.S., W.C., J.C., M.S.G., L.S.), Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts, USA; Infectious Disease Institute (P.J.M.B., N.B., J.C., M.S.G., L.S.), Harvard Medical School, Boston, Massachusetts, USA
| |
Collapse
|
2
|
Lopes G, Pinto E, Andrade PB, Valentão P. Antifungal activity of phlorotannins against dermatophytes and yeasts: approaches to the mechanism of action and influence on Candida albicans virulence factor. PLoS One 2013; 8:e72203. [PMID: 23951297 PMCID: PMC3741211 DOI: 10.1371/journal.pone.0072203] [Citation(s) in RCA: 82] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2013] [Accepted: 07/08/2013] [Indexed: 11/28/2022] Open
Abstract
In the last few decades, fungal infections, particularly nosocomial, increased all around the world. This increment stimulated the search for new antifungal agents, especially those derived from nature. Among natural products, those from marine sources have gained prominence in the last years. Purified phlorotannins extracts from three brown seaweeds (Cystoseira nodicaulis (Withering) M. Roberts, Cystoseira usneoides (Linnaeus) M. Roberts and Fucus spiralis Linnaeus) were screened for their antifungal activity against human pathogenic yeast and filamentous fungi. The purified phlorotannins extracts from the studied seaweeds displayed fungistatic and fungicidal activity against yeast and dermatophytes, respectively, pointing to their interest as anti-dermatophyte agent. C. albicans ATCC 10231 was the most susceptible among yeast, while Epidermophyton floccosum and Trichophyton rubrum were the most susceptible among dermatophytes. Since the antifungal mechanism constitutes an important strategy for limiting the emergence of resistance to the commercially available agents, the mechanism of action of purified phlorotannins extracts was approached. C. nodicaulis and C. usneoides seem to act by affecting the ergosterol composition of the cell membrane of yeast and dermatophyte, respectively. F. spiralis influenced the dermatophyte cell wall composition by reducing the levels of chitin. Phlorotannins also seem to affect the respiratory chain function, as all of the studied species significantly increased the activity of mitochondrial dehydrogenases and increased the incorporation of rhodamine 123 by yeast cells. Phlorotannins from F. spiralis inhibited the dimorphic transition of Candida albicans, leading to the formation of pseudohyphae with diminished capacity to adhere to epithelial cells. This finding is associated with a decrease of C. albicans virulence and capacity to invade host cells and can be potentially interesting for combined antifungal therapy, namely for the control of invasive candidiasis.
Collapse
Affiliation(s)
- Graciliana Lopes
- REQUIMTE/Laboratório de Farmacognosia, Departamento de Química, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal
| | - Eugénia Pinto
- CEQUIMED/Laboratório de Microbiologia, Departamento de Ciências Biológicas, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal
- * E-mail:
| | - Paula B. Andrade
- REQUIMTE/Laboratório de Farmacognosia, Departamento de Química, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal
| | - Patrícia Valentão
- REQUIMTE/Laboratório de Farmacognosia, Departamento de Química, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal
| |
Collapse
|
6
|
Hilmioglu S, Ilkit M, Badak Z. Comparison of 12 liquid media for germ tube production ofCandida albicansandC. tropicalis. Mycoses 2007; 50:282-5. [PMID: 17576320 DOI: 10.1111/j.1439-0507.2007.01359.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Infections caused by yeast of the genus Candida are the most common fungal infections, being Candida albicans the most common isolated species among them. The rapid identification of this yeast is mostly based on the production of germ tube in human or animal serum. This study describes the use of 12 different liquid media for germ tube production at 2, 2.5, 3 and 4 h. We examined 193 yeasts, including 157 (81.3%) C. albicans and 36 (18.7%) Candida tropicalis for the production of germ tube. The germ tube production of C. albicans was mostly observed in human serum (98%) followed by rabbit serum (89.8%), brain heart infusion broth (84%) and sheep serum (74.5%) at 2 h. An incubation time exceeding 2 h i.e. 2.5 h or later, C. tropicalis strains were observed to produce germ tubes. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for germ tube production of human serum at 2 h were 98%, 100%, 100% and 92.3% respectively. In all tested sera, an incubation period of more than 2 h improves the sensitivity, but decreases the specificity as well as PPV and NPV of germ tube test (GTT). In conclusion, human serum was observed to be the most appropriate medium to be preferred for GTT, with an incubation period of 2 h.
Collapse
Affiliation(s)
- Süleyha Hilmioglu
- Department of Microbiology, Faculty of Medicine, University of Ege, Izmir, Turkey.
| | | | | |
Collapse
|