P124 Best target for anti-A titer determination: A1 or A2 cells

Abstract

Aim To determine the appropriate target cell for assessment of anti-A titer in blood group B kidney transplant patients waiting for a deceased donor and qualify for blood group A2 (A subgroup) donors according to OPTN/UNOS guidelines. Methods 248 sera samples collected from 57 blood group B candidates (56% male, 79% African American) and tested after DTT treatment. Titers were done using A1 and A2 reagent target cells using the MTS Gel anti-IgG card method. Standard commercial blood bank reagents were used for all testing (2 donors per lot of A1 or A2 cells). The same technologist performed all titers. The titer for eligibility is ⩽ 8. Results 37 patients were eligible (titer ⩽ 8) with either A1 or A2 cells. 20 patients (35%) shown below had titers from 16 up to 128 with A1 cells. 2(4%) patients had a titer >8 with A2 cells. Of these 20 patients, the cPRA varied from 0–100% and was not correlated with anti-A titer. Sex and race was also not correlated with an anti-A titer ⩾ 8. Conclusions Patient eligibility may vary considerably depending on the target cell used. Additional clinical studies will be required to determine the optimum approach.