Re-evaluation of potency of IBRF-manufactured anti-A and anti-B blood grouping reagents against the new WHO international minimum potency standards

Background and ObjectivesABO blood group system antibodies agglutinate red blood cell suspension in physiologic serum directly without any reaction booster. In the present study the potency of IBRF-manufactured anti-A and anti-B blood grouping reagents by the hemagglutination method in test tube was reassessed against the new WHO international minimum potency standards. Materials and MethodsIn this experimental study, starting concentrations defined in WHO standards were used in titration. Doubled dilution series of WHO standards (from starting concentrations) and IBRF blood grouping reagents (from neat) were prepared by using buffered saline containing 2% BSA as diluent. One volume of each starting concentration together with one volume of prepared dilutions were mixed with one volume of a 2% suspension of A1, A2, A2B, and B cells in glass test tubes, respectively. After appropriate incubation and centrifugation of the tests according to specified criteria, the reactions were graded macroscopically. ResultsThe results showed that the IBRF anti-A and anti-B blood grouping reagents comply with the minimum WHO standard dilution. Consequently, IBRF anti-A and anti-B blood grouping reagents were shown to be safe for screening and diagnostic purposes. ConclusionsThe quality of blood grouping reagents is clearly an important factor for safe blood transfusion. Routine titration tests are not reliable methods for evaluation of those reagents. Fortunately, this problem would be solved using the above standards. This recommended method is provided to help assist manufacturers in pursuing new product license applications and making amendments in existing ones.