Abstract
An enzyme-linked antiglobulin test was used to quantify the amount of Ig[immunoglobulin]G antibodies on [human] red blood cells. Erythrocytes were sensitized with various blood group antibodies, washed, incubated with antiglobulin conjugated with alkaline phosphatase, washed, substrate was added and the optical density of the product was measured. This optical density was linearly proportional to the concentration of red blood cell antibodies incubated with the cells. The assay was easy to perform, had a standard deviation of 7% on replicated assays, and was more sensitive than the manual antiglobulin test.