2018 Volume 64 Issue 1 Pages 43-49
Flow cytometric detection of anti-HLA antibodies has yet to be optimally standardized. There is no consensus on whether serum or plasma specimens should be used. We studied interspecimen differences in anti-HLA antibody levels between serum and plasma using the flow cytometric method FlowPRA®. We simultaneously examined the serum and plasma of a total of 55 cases that were positive or negative for anti-HLA antibodies. The percentage of class I and class II beads that reacted with plasma was significantly correlated with those that reacted with serum (class I: r = 0.8570 p < 0.0001, class II: r = 0.7529 p < 0.0001). Plasma and serum, samples that were positive for anti-HLA antibodies were identical in all 55 cases for class I and in 54 cases for class II. In one case, class II anti-HLA antibodies were detected in plasma but not in serum. Mean fluorescence intensity in plasma samples was significantly higher than that in serum. Non-specific reaction due to high background intensity was seen in 2 plasma specimens out of 55 cases. Therefore, both serum and plasma specimens are useful for detecting anti-HLA antibodies using Flow PRA®, although the features of each specimen should be considered.
