Clinical Usefulness of Monitoring Expression Levels of CCL24 (Eotaxin-2) mRNA on the Ocular Surface in Patients with Vernal Keratoconjunctivitis and Atopic Keratoconjunctivitis

Purpose. This study aimed to evaluate the clinical efficacy of using expression levels of CCL24 (eotaxin-2) mRNA on the ocular surface as a biomarker in patients with vernal keratoconjunctivitis (VKC) and atopic keratoconjunctivitis (AKC). Methods. Eighteen patients with VKC or AKC (VKC/AKC group) and 12 control subjects (control group) were enrolled in this study. The VKC/AKC clinical score was determined by objective findings in patients by using the 5-5-5 exacerbation grading scale. All subjects underwent modified impression cytology and specimens were obtained from the upper tarsal conjunctiva. Expression levels of CCL24 (eotaxin-2) mRNA on the ocular surface were determined using real-time reverse transcription polymerase chain reaction. Results. The VKC group was divided into two subgroups, depending on the clinical score: the active stage subgroup with 100 points or more of clinical scores and the stable stage subgroup with 100 points or less. CCL24 (eotaxin-2) mRNA expression levels in the active VKC/AKC stage subgroup were significantly higher than those in the stable VKC/AKC subgroup and the control group. Clinical scores correlated significantly with CCL24 (eotaxin-2) mRNA expression levels in the VKC group. Conclusions. CCL24 (eotaxin-2) mRNA expression levels on the ocular surface are a useful biomarker for clinical severity of VKC/AKC.