Biocompatibility of Pooled Human Immunoglobulin (Gamunex 10%™) with Ocular Infusion Solutions (BSS™ and BSS Plus™): An In Vitro Evaluation of a Potential Antitoxin Treatment for Infectious Endophthalmitis

Abstract

Gamunex 10% (Talecris Biotherapeutics, Research Triangle Park, NC), a commercially available preparation of pooled human immunoglobulin G, has been proposed as an antitoxin therapy against bacterial toxins released in infectious endophthalmitis. Its biocompatibility with two commonly used intraocular infusion fluids was evaluated to determine feasibility of its clinical application in endophthalmitis treatment. Gamunex 10% was mixed with BSS or BSS Plus (Alcon Laboratories, Fort Worth, TX) such that it constituted a range of 1.25%-50% by volume. Osmolality, pH, optical density, and ionic strength were measured across this range of concentrations. The amount of pH reduction with increasing concentrations of Gamunex 10% was similar for both BSS and BSS Plus. In BSS Plus, solutions containing up to 20% by volume of Gamunex 10% remained at near-physiologic pH (∼7.0 or above). No physiologically significant changes in osmolality or optical density measurements that would be anticipated to have profound physiological effects were observed at any of the measured concentrations, nor was there visual evidence of tubidity/precipitation. A gradual increase in ionic strength was observed with increasing concentrations of Gamunex 10%. Potentially therapeutic mixtures of Gamunex 10% in 2 commonly used intraocular infusion fluids, BSS and BSS Plus, showed no evidence of bioincompatibility when the solutions were evaluated for changes in osmolality, pH, ionic strength, aggregation, or precipitation.