Abstract
Purpose :
Current diagnosis of dry eye disease (DED) has significant challenges with limited accuracy and poor correlation of clinical symptoms. The goal of this study is to develop a sensitive lateral flow immunoassay (LFIA) for point of care (POC) diagnosis of DED. The authors tested the hypothesis of targeting dual biomarkers Interleukin-6 (IL-6) and lactoferrin in tears for multiplexing detection, as to increase the accuracy of POC diagnosis for DED. A standardized tear collection protocol was also developed with the use of disposed contact lenses. The initial trial of 20 tear samples provided positive LFIA results for future clinical studies.
Methods :
1. Production of LFIA paper strips printed with gold nanoparticle conjugates, antibodies against human IL-6 or lactoferrin & antimouse antibody.
2. Determination of lowest detection limits of LFIA with serial diluted concentrations of rIL-6 or lactoferrin solutions
3. Confirmation of LFIA results with the conventional ELISA method
4. De-identified and discarded contact lens were collected with the consent of the patients
5. Application of 50 μL tear samples onto a LFIA paper strip for detection of tear IL-6 or lactoferrin
6. Image capture of LFIA paper strips 10 minutes after LFIA test
7. Quantitative data analysis of LFIA paper strips with ImageJ software
8. Student t test was used for statistical analysis
Results :
A paper-based LFIA was successfully developed in a double-antibody sandwich fashion with gold nanoparticles acting as probes. The minimal detection concentrations were 0.1 ng/ml and 10 ng/ml for IL-6 and lactoferrin, respectively. Separated ELISA tests were also performed with data confirming results from LFIA tests. A trial study was conducted with 20 tear samples. Compared to the controls, all 10 DED tears exhibited statistically significantly higher levels of IL-6 and decreased levels of lactoferrin. A quantitative analysis of LFIA images was carried out using ImageJ software for an accurate data interpretation. A smartphone-based platform is being developed for LFIA imaging, data reporting and storage.
Conclusions :
In summary, a POC enabled DED diagnostic kit has been successfully developed by targeting two important biomarkers. Tear testing of IL-6 and lectoferrin demonstrated a positive correlation of LFIA results with DED symptoms. Further investigations are warranted to improve its accuracy for clincal diagnosis of DED
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.