P242 Luminex crossmatch for detection of DSA in haploidentical stem cell transplantation

Abstract

Aim The study was performed to evaluate the usefulness of Luminex crossmatch (LXM) alone or in combination with pooled bead assay for detection of donor specific antibodies in potential recipients of haploidentical Haematopoietic Stem Cell Transplantation. Methods Forty-four potential HSCT recipients and their 74 haploidentical donors were evaluated in a CAP accredited laboratory in India. HLA typing was performed for HLA-ABCDRDQB1 by DNA based methods. LXM was carried out on all 44 patients’ samples against 74 lysates prepared from 1 to 5 different donors. Twenty- two patients’ sera were screened by pooled bead assay for HLA- class I and II IgG antibodies. All tests were performed in accordance with the protocol mentioned in product insert. Results Fifty-two samples were LXM negative. HLA-Class I IgG DSA was detected in four samples, 12 were positive for HLA-class II IgG DSA and both were positive in six samples. Five samples (6.8%) gave a false positive LXM results (Class II 4, both 1) two of these showed auto LXM positivity. False positivity was excluded by pooled bead assay, correlation of HLA typing results and auto-LXM. Conclusions LXM in combination with pooled bead assay is likely to be a useful for detection of anti HLA-ABDR DSA in haploidentical HSCT. The test needs to be evaluated in multiple centres on larger sample size and if resources permit a parallel testing with SAB assay to conclusively establish its role. Download : Download high-res image (279KB) Download : Download full-size image