Mechanisms involved in conjunctival immunological tolerance breakdown by eye drop preservatives

GALLETTI JEREMÍAS GASTÓN; GABELLONI MARÍA LAURA; SABBIONE FLORENCIA; CHIARADÍA PABLO; GIORDANO MIRTA NILDA; CASIRAGHI JAVIER

Seattle, WA

Congreso; ARVO 2013 Annual Meeting; 2013

ARVO

Purpose:To evaluate the molecular and celular mechanisms involved in the disruptive immune effect of benzalkonium chloride (BAK) on the ocular surface. Methods:A previously validated in vivo murine model was used (Mucosal Immunol. 2012 Jun 13. doi: 10.1038/mi.2012.44). In brief, Balb/c mice were given ovalbumin (OVA) alone or in combination with 0.01% BAK (B+O) daily for 5 days in both eyes, with and without nuclear factor B (NFB) pathway inhibitors: pyrrolidine dithiocarbamate (PDTC) and sulfasalazine (SSZ). On day 7, mice were immunized intraperitoneally with OVA in alum to evaluate the systemic response on day 14 as OVA-induced splenocyte proliferation by thymidine incorporation. To model in vitro the ocular surface epithelium, Pam212 cells were exposed for 15 min to different BAK concentrations (0.00001%-0.01%), then cultured for 96 h with syngeneic splenocytes and finally cell viability and expression of major histocompatibility complex class II (MHC-II) as activation marker were assayed. Results:In the in vivo model, OVA instillation induced conjunctival tolerance (43±9% of control systemic response, p