1. Assessment of donor-derived kir by sequential cDNA genotyping in non t cell depleted haploidentical stem cell transplanted patients
- Author
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Canossi, Angelica, Anna Aureli, Del Beato, Tiziana, Arcese, William, Papola, Franco, Santarone, Stella, Arriga, Roberto, Di Bartolomeo, Paolo, and Sconocchia, Giuseppe
- Subjects
immune system diseases ,embryonic structures ,otorhinolaryngologic diseases ,haploidentical bone marrow transplantation ,hemic and immune systems ,chemical and pharmacologic phenomena ,cDNA genotyping ,Settore MED/15 - Malattie del Sangue ,KIR - Abstract
Following haploidentical hematopoietic stem cell transplantation (HSCT), donor alloreactive NK cells contribute to the elimination of recipient leukemia blasts, dendritic cells and T lymphocytes. The aims of the study were: a) to determine the recipient KIR genotype profiling through sequential (pre-Tx, 1 and 3 months 1 year post-HSCT) genotyping in patients who underwent HSCT undergoing non T cell depleted HSCT and b) to estimate the reconstitution of KIR loci on the basis of donor KIR genotypes. DNA and RNA were isolated from peripheral blood of 10 donors/recipient pairs using QIamp DNA Blood Midi kit and a Tempus Spin RNA isolation Reagent kit, respectively. cDNA was obtained by reverse transcription using RNA as template and random primers. KIR genotyping and gene expression profiling were performed using a KIR SSP typing kit (Miltenyi Biotec GmbH) that detects 17 KIR genes. Four patients developed acute Graft versus Host Disease (aGvHD), 1 patient relapsed and 4 patients died of GvHD, relapse or pneumonia. Among 10 patients, 6 had more than 2 KIR-ligand mismatches in aGVHD direction. Sequential KIR genotyping showed genotype changes during recipients' hematopoietic recovery. Although it is not clear whether KIR cell reconstitution is promoted by donor NK or donor T cells contained in the graft, we observed rapid appearance of donor KIR profiles. Interestingly, 6 patients without aGvHD or relapse had a full donor KIR profile from the first month post-transplant, while 4 patients with aGvHD or relapse turned from a full donor KIR profile to a donor/recipient mixed KIR chimerism at the moment of immunological event. In addition, during KIR reconstitution monitoring, we noted different levels of expression in 3DL1 (disappearance after 3 month) and 2DS1, 2DL2, 2DL3 (early appearance), and 2DS4ins, 2DS2, 2DS3, 3DL3 KIR loss. Our data suggest that this type of analysis may be useful for monitoring chimerism, KIR reconstitution as well as for distinguishing between alleles and nulls. Our results may help to understand the effect of ligand-KIR donor mismatches on transplant outcome.
- Published
- 2012