Hyeon-Man Kim

Profiling of factor VIII mutations in Korean haemophilia A

Summary.  Haemophilia A (HA) is an X chromosome‐linked inherited bleeding disorder caused by heterogeneous mutations of coagulation factor VIII (FVIII). Although more than 900 mutations of FVIII gene are reported in the HAMSTeRS database, the mutation data regarding the FVIII gene in the Korean population is currently insufficient. The aim of this study was to profile the mutations of FVIII in Korean HA, 38 unrelated Korean HA male patients were examined. Peripheral blood samples were obtained from the patients. Long distance‐PCR was performed for the identification of inversions in intron 22 and intron 1. Then gross exon deletion was examined to the inversion‐negative patients by multiplex‐PCR. Finally, direct sequencing was performed on exons 1–26, 5’‐ and 3’‐UTR. We identified 33 mutations from the 38 patients. These included 15 inversions in intron 22 (39.5%), one inversion in intron 1 (2.6%), one gross exon deletion (2.6%), five deletions (13.2%), two insertions (5.3%), six missense (15.8%) and three nonsense mutations (7.9%). Mutation types for five patients (13.2%) were not identified in this study. We determined that the most common defect in FVIII in this study was an inversion mutation in intron 22; this is consistent with the findings of other studies. For the first time in Korean HA, a patient with intron 1 inversion was found. In addition, we report eight novel mutation types which never been reported in HAMSTeRS database. The mutation data in this study should prove useful as a reference for the diagnosis of HA and the detection of carriers in the Korean population.

Auxiliary Partial Orthotopic Liver Transplantation as a Treatment for Hemophilia A: A Case Report

A 37-year-old man with moderately severe hemophilia A (factor VIII of 1.2%), who had a normal liver without liver cirrhosis or hepatocellular carcinoma, was referred to our liver transplantation (LT) team. LT was planned for sufficient coagulation factor level maintenance and prophylaxis against future hemorrhagic complications. The donor was the patients 35-year-old wife, who was nonhemophilic. We performed an auxiliary partial orthotopic liver transplantation (APOLT) with the approval of the Institutional Ethics Committee. A left partial liver graft taken from the donor was orthotopically transplanted to the recipient after resection of the native left hemiliver while preserving the native right lobe. After surgery, the patient tolerated the procedure, and tacrolimus was used to maintained immunosuppression. In this recipient, factor VIII activity significantly increased soon after the APOLT, and has been maintained at >20% without any further bleeding episodes for the past 74 months since the procedure. This finding suggests that APOLT may be an effective alternative treatment for patients with hemophilia A.

Profiling of differentially expressed genes in haemophilia A with inhibitor

Summary.  Inhibitor development is the most significant complication in the therapy of haemophilia A (HA) patients. In spite of many studies, not much is known regarding the mechanism underlying inhibitor development. To understand the mechanism, we analysed profiles of differentially expressed genes (DEGs) between inhibitor and non‐inhibitor HA via a microarray technique. Twenty unrelated Korean HAs were studied: 11 were non‐inhibitor and nine were HA with inhibitor (≥5 BU mL−1). Microarray analysis was conducted using a Human Ref‐8 expression Beadchip system (Illumina) and the data were analysed using Beadstudio software. We identified 545 DEGs in inhibitor HA as compared with the non‐inhibitor patients; 384 genes were up‐regulated and 161 genes were down‐regulated. Among them, 75 genes whose expressions were altered by at least two‐fold (>+2 or <−2) were selected and classified via the PANTHER classification method. The expressions of signal transduction and immunity‐related genes differed significantly in the two groups. For validation of the DEGs, semi‐quantitative RT‐PCR (semi‐qRT‐PCR) was conducted with the six selected DEGs. The results corresponded to the microarray data, with the exception of one gene. We also examined the expression of the genes associated with the antigen presentation process via real‐time PCR. The average levels of IL10, CTLA4 and TNFα slightly reduced, whereas that of IFNγ increased in the inhibitor HA group. We are currently unable to explain whether this phenomenon is a function of the inhibitor‐inducing factor or is an epiphenomenon of antibody production. Nevertheless, our results provide a possible explanation for inhibitor development.