CXCL8 and infection: CXCL8 is expressed by various ocular surface cell types, including corneal and conjunctival epithelial cells, corneal keratocytes, PMNs, and macrophages, in response to the infection (Elner et al., 1991; Oakes et al., 1993; Scapini et al., 2000; Venza et al., 2007; Waugh and Wilson, 2008; Shtein et al., 2012).