Fungal keratitis (FK) is a type of infectious keratitis with a high risk of causing blindness. Therefore, it is crucial to identify effective diagnostic indicators and understand its pathological mechanism. Quantitative Reverse Transcription polymerase chain reaction (qRT-PCR) was employed to detect miR-21-5p expression in tears, serum, and corneal tissues from patients with FK and non-infectious keratitis (NIK) controls. Pearson correlation analysis was used to assess the expression correlation of miR-21-5p across different sample types. Additionally, the correlations between miR-21-5p and the pro-inflammatory cytokines IL-6, TNF-α, and IL-1β were analyzed. The expression of miR-21-5p in each sample of the FK group was significantly higher than that of the NIK group, and the expression in corneal tissue was higher than that in tears and serum. In the FK group, the expression levels of IL-6, TNF-α and IL-1β varied significantly among the three sample types (all P < 0.001). The expression of miR-21-5p was significantly positively correlated with the levels of IL-6, TNF-α and IL-1β in serum, tear fluid and corneal tissue (all P < 0.001). miR-21-5p is highly expressed in FK serum, tears, and corneal tissues, and the expression of miR-21-5p is positively correlated with the levels of inflammatory factors.
Liu et al. (Tue,) studied this question.