CHARACTERIZATION OF CYTOKINE MESSENGER-RNA TRANSCRIPTS IN CONJUNCTIVAL CELLS IN PATIENTS WITH ALLERGIC CONJUNCTIVITIS

Purpose. The host response to allergens appears to be regulated by spe cific patterns of local cytokine production. More than 20,000 conjunct ival superficial cells were collected with a special brush, a smaller version of the Cytobrush used in cervical cytology, from the upper pal pebral conjuntiva. Methods, Samples were obtained by cytology brush fr om seven patients with allergic conjunctivitis and from seven healthy volunteers. Giemsa staining, immunocytochemistry, and flow cytometric analysis were performed. Cytokine gene expression was assayed by the r everse-transcription-polymerase chain reaction method. Results. Giemsa staining of cytocentrifuged preparations from patients with allergic conjunctivitis showed conjunctival epithelial cells with lymphocytes, mast cells, and eosinophils. In an immunohistochemical study, a few CD 3- and CD4- bearing cells, but not CD20- and CD14-bearing cells, were seen in patients. In 82.6 +/- 17% of the samples obtained from allergi c patients, HLA-DR was present, but it was present in only 34.2 +/- 17 .8% of samples from control subjects (P = 0.0001) using flow cytometri c analysis. Steady state transcripts of mRNA for cytokines were analys ed with RT-PCR in conjunctival cell samples, and results showed that s amples from allergic conjunctivitis expressed increased transcripts of interleukin 4 and interleukin 13 but virtually no interleukin 2 or in terferon-gamma; six samples from seven healthy subjects expressed no i nterleukin 2, interleukin 4, interleukin 13, or interferon-gamma trans cripts. Conclusions. These results suggest that the clinical features of allergic conjunctivitis in humans are associated with a specific lo cal pattern of proinflammatory cytokine expression.