» Anti-A Blood Grouping Serum conforms to the regulations of the federal Food and Drug Administration concerning biologics (660.20 to 660.29) (see Biologics 1041). It is a sterile, liquid or dried preparation containing the particular blood group antibodies derived from high-titered blood plasma or serum of human subjects, with or without stimulation by the injection of Blood Group Specific Substance A (or AB). It agglutinates human red cells containing A-antigens, i.e., blood groups A and AB (including subgroups A1, A2, A1B, and A2B but not necessarily weaker subgroups). It contains a suitable antimicrobial preservative. It meets the requirements to the test for potency, in parallel with, and not less than equivalent to, the U.S. Reference Blood Grouping Serum Anti-A, in agglutinating red blood cells from Group A1 and Group A2B donors. It meets the requirements of the tests for specificity with Group A1, A2B, B, and O cells and confirms the absence of contaminating antibodies reactive with Mg, Wra antigens as well as other antigens having an incidence of 1 percent or greater in the general population (see under Blood Grouping Serums Anti-D, Anti-C, Anti-E, Anti-c, Anti-e). It meets the requirements of the tests for avidity with Group A1 and A2B cells. All fresh or frozen red blood cell suspensions used for these tests are prepared under specified conditions and meet specified criteria. Anti-A Blood Grouping Serum may be artificially colored blue.