#41
CHIMERISM FROM LOW YIELDS OF EXTRACTED DNA DETECTED BY MULTIPLEX ASSAY SYSTEM (LUMINEX).
Walter Herczyk MT(ASCP), CHS 1, Bobbie Holeman HHS 1, Dongfeng Chen Phd., D(ABHI) 1 and Nancy Reinsmoen Phd., D(ABHI) 1. 1 Pathology, Duke University Medical Center, Durham, NC, USA .
Samples are routinely sent to HLA laboratories for monitoring recipients who receive HLA mismatched cord blood or haploidentical graft transplants. It is very important in assessing a recipient
s progress to identify donor cell engraftment or any return of recipient alleles. Stem cell patients that have under gone a transplant can be a challenge to test since the amount of extracted DNA obtained from the samples that range from blood to buccal swabs can yield small volumes of DNA, limiting the testing. The multiplex assay system (Luminex) can be useful in some cases since the amount of DNA needed for the Luminex-based reverse sequence-specific oligonucleotide (rSSOP) testing is very small compared to sequence-specific primers (SSP). A buccal swab was received for DNA extraction, the amount and concentration of DNA obtained was as follows; 50ul at 74ng/ml. DNA needed for SSP ABDRDQ testing is 80ul at 100ng/ul, whereas the volume and concentration for LabTypeTM (rSSOP) ABCDRDQ is 12ul at 20ng/ul. Since the amount of DNA extracted was below SSP requirements, Luminex (rSSOP) was used for testing. The results showed a chimerism with both patient and donor alleles from the buccal sample. By comparing the normalized values from the LabTypeTM analysis program to the established cutoff values, both recipient and donor Class I and Class II alleles were detected. In this case, the DNA extracted from the buccal swab in conjunction with multiplex assay system was sensitive enough to detect chimerism for this recipient.