title: Clinical Usefulness of Simultaneous Measurement of the Tear Levels of CCL17, CCL24, and IL-16 for the Biomarkers of Allergic Conjunctival Disorders.
abstract: This study investigated the clinical usefulness of a multiple tear cytokine/chemokine test by simultaneously determining tear levels of CC chemokine ligand 17 (CCL17)/thymus and activation-regulated chemokine (TARC), CCL24/eotaxin-2, and interleukin-16 (IL-16) for assessing acute and chronic allergic inflammation in allergic conjunctival disorders (ACDs).
  
  
  
  This study included 37 patients with ACD and 11 healthy adults (controls). Patients with ACDs were divided into the following three groups; patients with allergic conjunctivitis (AC group, n = 17), patients with atopic keratoconjunctivitis (AKC group, n = 6), and patients with vernal keratoconjunctivitis (VKC group, n = 14). Tear samples were collected using the Schirmer I method with a filter paper. Tear levels of CCL17/TARC, CCL24/eotaxin-2, and IL-16 were determined by performing a magnetic bead assay (tear cytokine/chemokine test). Tear levels of eosinophil cationic protein (ECP) were determined by performing enzyme immunoassay. In patients with AC, clinical scores of objective findings and results of the tear cytokine/chemokine test at baseline were compared with those at 7 days after treatment with the histamine H1receptor antagonist (epinastine) ophthalmic solution.
  
  
  
  Tear positive rates of CCL17/TARC, CCL24/eotaxin-2, and IL-16 were higher in patients with AC, AKC, and VKC compared with controls. Tear levels of CCL17/TARC, CCL24/eotaxin-2, and IL-16 in patients with AKC and VKC were significantly higher than those in patients with AC. Moreover, tear levels of IL-16 in patients with AC that showed improvement of their clinical score by treatment with epinastine ophthalmic solution decreased significantly after 7 days of the treatment compared with those at baseline. In patients with AKC and VKC, a significant correlation was observed between the tear levels of CCL24/eotaxin-2 and ECP.
  
  
  
  Simultaneous measurement of the tear levels of CCL17/TARC, CCL24/eotaxin-2, and IL-16 may be a useful test for assessing acute and chronic allergic inflammation in ACDs.
authors.affiliation: a Division of Ophthalmology, Department of Visual Sciences , Nihon University School of Medicine , Tokyo , Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Shoji
authors.affiliation: a Division of Ophthalmology, Department of Visual Sciences , Nihon University School of Medicine , Tokyo , Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Aso
authors.affiliation: a Division of Ophthalmology, Department of Visual Sciences , Nihon University School of Medicine , Tokyo , Japan.
authors.forename: Noriko
authors.initials: N
authors.lastname: Inada
mesh_terms: D000293:Adolescent; D000328:Adult; D015415:Biomarkers / Q000378:metabolism; D054414:Chemokine CCL17 / Q000378:metabolism*; D054423:Chemokine CCL24 / Q000378:metabolism*; D003233:Conjunctivitis, Allergic / Q000175:diagnosis / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D019410:Interleukin-16 / Q000378:metabolism*; D008297:Male; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012720:Severity of Illness Index; D013666:Tears / Q000378:metabolism; D055815:Young Adult
chemical_list: D015415:Biomarkers; C106230:CCL17 protein, human; C515484:CCL24 protein, human; D054414:Chemokine CCL17; D054423:Chemokine CCL24; D019410:Interleukin-16
keywords: Allergic conjunctival disorders; CCL17; CCL24; IL-16; tear test