Naslov
LOSS OF MISMATCHED HLA HAPLOTYPE IN HAPLOIDENTICAL HEMATOPOIETIC STEM CELL TRANSPLANTATION

Autori
Maskalan, Marija ; Burek Kamenarić, Marija ; Grubić, Zorana ; Duraković, Nadira ; Bralić, Sara ; Štingl Janković, Katarina ; Serventi Seiwerth, Ranka ; Vrhovac, Radovan ; Žunec, Renata

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
ABSTRACT BOOK Joint 34th European Immunogenetics and Histocompatibility and 31st British Society for Histocompatibility and Immunogenetics Conference / - , 2020, 382-383

Skup
34th European Immunogenetics and Histocompatibility ; 31st British Society for Histocompatibility and Immunogenetics Conference

Mjesto i datum
Glasgow, Ujedinjeno Kraljevstvo, 26.04.2020. - 29.04.2020

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
HLA, haploidentical HSCT

Sažetak
Haploidentical hematopoietic stem cell transplantation (HSCT) can extend opportunity for transplantation for almost all patients who lack an HLA-matched donor. Genomic loss of mismatched HLA haplotype (HLA loss) is a clinically-relevant mechanism of leukemia immune evasion and relapse after haploidentical HSCT. The aim of this study was to retrospectively analyze incidence of HLA loss in sixty patients transplanted with haploidentical donor at UHC Zagreb in period 2012-2019 for treatment of acute leukemia (N=28), lymphoma (N=26) or other hematological malignancies (N=6). Post- HSCT chimerism status was monitored by Real-Time PCR (qPCR). Mixed chimerism monitoring results identified 22 patients at higher risk for relapse, which was clinically confirmed for 12 (54.5%) of them. All 12 patients were tested for HLA loss at all HLA class I and class II informative loci using HLA typing by PCR-SSP. HLA loss was detected in two patients. Patient 1 relapsed 6 years after HSCT, at which time chimerism monitoring detected 80% of patient cells. HLA typing revealed loss of patient’s mismatched allele at all three informative loci (HLA-A, - B, -C). Patient 2 relapsed 5 months after HSCT, with chimerism monitoring result of 2% of patient cells. In this patient HLA-A and -DPB1 loci were informative and at both mismatched allele loss was detected. Ten patients relapsed without HLA loss with mixed chimerism monitoring results and the level of patient cells ranging from 2%-80%. In all cases PCR-SSP testing was successful in detecting mismatched patient alleles, however in cases of lower level of patients’ cells (2-15%) bands were less intensive, but still clearly positive. The results suggest that the PCR-SSP method is sufficiently sensitive and can be used for detection of patient-specific HLA haplotype loss, providing clinically relevant information for relapse treatment even in cases with low level of patient cells in peripheral blood.

Izvorni jezik
Engleski

Znanstvena područja
Biologija, Kliničke medicinske znanosti

POVEZANOST RADA