Antibody Titers Study in Group O Blood Donors: Tube and Column Agglutination Techniques

Sood R, Neelima, Kumar D, Kumar T, Kumar V, Rani S and Kumar S

Background: O blood group transfusions to patients of all blood groups has continued since long. Clinical significance of ABO antibody titre in ABO-I kidney transplantation is well known. Few studies done on group O blood/ apheresis donations, for detecting ABO antibody titers in collected plasma components. The passively acquired antibodies may destroy recipient’s own red cells and tissue grafts, cause acute hemolysis, hemoglobinemia, jaundice, progressive anemia, spontaneous agglutination, positive direct antiglobulin test and increased osmotic fragility of the patient’s red cells.
Objective: To evaluate agglutinin levels in group O blood donations. Group O donor population, randomly selected and titrated using tube technique and gel card technique to identify titer levels for Anti A, Anti B, Anti AB antibodies. Both IgM and IgG titer levels evaluated.
Methods: Plasma samples from 200 randomly selected blood group O donors were tested by ABO antibody titration using conventional tube technique and AHG gel card column agglutination technique (CAT). ABO antibody levels categorized as those higher than 16 and those lower than 16. After treatment with Dithiothretiol (DTT) for characterization of only IgG class, titres levels were again tested in same O group blood/apheresis donors. Statistical analyses performed using various tests.
Results: Males constituted 88% of O group donors studied and 12% were females. ABO antibody titer categorized as 0 to ≤16 and titer >16 for both IgM and IgG antibody for Anti A, Anti B and Anti AB. Both test tube and CAT used for testing. Estimates of prevalence of titers by CAT: Anti A IgM ≤ 16 in 62%; >16 in 38% (p-value < 0. 001); Anti A IgG ≤ 16 in 32%; >16 in 68% (p-value < 0. 001); Anti B IgM ≤ 16 in 69%; >16 in 31% (p-value < 0.001); Anti B IgG ≤ 16 in 35%; >16 in 65% (p-value < 0.001); Anti AB IgM ≤ 16 in 30%; >16 in 70% (p-value < 0.001); Anti AB IgG ≤ 16 in 27%; >16 in 73% (p-value < 0.001); And estimations of prevalence for titers using tube technology: Anti A IgM ≤ 16 in 44%; >16 in 56% (p-value < 0.045); Anti A IgG ≤ 16 in 44%; >16 in 56% (p-value < 0.045); Anti B IgM ≤ 16 in 51%; >16 in 49% (p-value < 0. 0.389); Anti B IgG ≤ 16 in 36%; >16 in 64% (p-value < 0.001); Anti AB IgM ≤ 16 in 34%; >16 in 66% (p-value < 0.001); Anti AB IgG ≤ 16 in 4%; >16 in 96% (p-value < 0.001). No significant co-relation found between age and titer or gender and titer, by both technologies. Mean anti-A and anti-B and anti-AB titers in group O plasma were, respectively,163.28,113.42 and 166.77 for IgM antibody and 174.50,152.98 and 311.63 for IgG antibody by tube method and 34.01,33.30 and 63.77 for IgM Antibody,108.41,103.10 and 272.46 for IgG antibody by CAT (p < 0.0001).
Conclusion: Study confirms that titration of ABO antibodies in blood banks will increase safety in non-identical ABO transfusions and transplants. No significant correlation established between titer and age or titer and gender.