EDTA/glycine-acid versus chloroquine diphosphate treatment for stripping Bg antigens from red blood cells

Abstract

EDTA/glycine-acid (EGA) has been reported to remove IgG-bound antibodies from red blood cells (RBCs) and to denature Kell system and Era antigens. EGA-treated RBCs were tested in parallel with chloroquine diphosphate (CDP)-treated RBCs to evaluate whether EGA would remove Bg antigens from RBCs as efficiently as CDP. Fifty-seven serum/plasma samples containing known Bg antibodies were tested with untreated Bg+ RBCs, EGA-treated Bg+ RBCs, and CDP-treated Bg+ RBCs by an indirect antiglobulin test (IAT), using a low-ionic-strength additive solution and murine monoclonal polyspecific antiglobulin reagent. Of 57 samples, 40 (22 anti-Bga, 17 anti-Bgb, and 1 Bg-related) were nonreactive by IAT with EGA-treated RBCs and CDP-treated RBCs, 14 (7 anti-Bga, 4 anti-Bgb, and 3 Bg-related) were nonreactive by IAT only with EGA-treated RBCs, none were nonreactive in IAT with only CDP-treated RBCs, and 3 (anti-Bga) were still reactive by IAT with EGA-treated RBCs and CDP-treated RBCs. Therefore, EGA strips Bg antigens from RBCs. Our results indicate EGA treatment is more efficient and requires less time (1–2 minutes) to perform than the CDP procedure (30–120 minutes) for removal of Bg antigens from RBCs. Immunohematology 1999;15:66–68.