Rieko Kubo

Type of skin eruption is an independent prognostic indicator for adult T-cell leukemia/lymphoma

Cutaneous involvement is seen in ~ 50% of adult T-cell leukemia/lymphoma (ATLL) patients. We investigated the association between skin eruption type and prognosis in 119 ATLL patients. ATLL eruptions were categorized into patch (6.7%), plaque (26.9%), multipapular (19.3%), nodulotumoral (38.7%), erythrodermic (4.2%), and purpuric (4.2%) types. When the T stage of the tumor-node-metastasis-blood (TNMB) classification of mycosis fungoides/Sézary syndrome was applied to ATLL staging, 16.0% were T1, 17.7% T2, 38.7% T3, and 4.2% T4, and the remaining 23.5% were of the multipapular and purpuric types. For the patch type, the mean survival time (median survival time could not be estimated) was 188.4 months. The median survival times (in months) for the remaining types were as follows: plaque, 114.9; multipapular, 17.3; nodulotumoral, 17.3; erythrodermic, 3.0; and purpuric, 4.4. Kaplan-Meier curves of overall survival showed that the erythrodermic type had the poorest prognosis, followed by the nodulotumoral and multipapular types. The patch and plaque types were associated with better survival rates. Multivariate analysis demonstrated that the hazard ratios of the erythrodermic and nodulotumoral types were significantly higher than that of the patch type, and that the eruption type is an independent prognostic factor for ATLL. The overall survival was worse as the T stage became more advanced: the multipapular type and T2 were comparable, and the purpuric type had a significantly poorer prognosis than T1.

Expression of ABO blood-group genes is dependent upon an erythroid cell-specific regulatory element that is deleted in persons with the B(m) phenotype.

The ABO blood group is of great importance in blood transfusion and organ transplantation. However, the mechanisms regulating human ABO gene expression remain obscure. On the basis of DNase I-hypersensitive sites in and upstream of ABO in K562 cells, in the present study, we prepared reporter plasmid constructs including these sites. Subsequent luciferase assays indicated a novel positive regulatory element in intron 1. This element was shown to enhance ABO promoter activity in an erythroid cell-specific manner. Electrophoretic mobility-shift assays demonstrated that it bound to the tissue-restricted transcription factor GATA-1. Mutation of the GATA motifs to abrogate binding of this factor reduced the regulatory activity of the element. Therefore, GATA-1 appears to be involved in the cell-specific activity of the element. Furthermore, we found that a partial deletion in intron 1 involving the element was associated with B(m) phenotypes. Therefore, it is plausible that deletion of the erythroid cell-specific regulatory element could down-regulate transcription in the B(m) allele, leading to reduction of B-antigen expression in cells of erythroid lineage, but not in mucus-secreting cells. These results support the contention that the enhancer-like element in intron 1 of ABO has a significant function in erythroid cells.

Mutation of the GATA site in the erythroid cell–specific regulatory element of the ABO gene in a Bm subgroup individual

The ABO blood group is important in blood transfusion. Recently, an erythroid cell–specific regulatory element has been identified in the first intron of ABO using luciferase reporter assays with K562 cells. The erythroid cell–specific regulatory activity of the element was dependent upon GATA‐1 binding. In addition, partial deletion of Intron 1 including the element was observed in genomic DNAs obtained from 111 Bm and ABm individuals, except for one, whereas the deletion was never found among 1005 individuals with the common phenotypes.

Deletion of the RUNX1 binding site in the erythroid cell-specific regulatory element of the ABO gene in two individuals with the Am phenotype.

An erythroid cell‐specific regulatory element, referred to as the +5·8‐kb site, had been identified in the first intron of the human ABO blood group gene. Subsequent studies revealed that either a 5·8‐kb deletion including the +5·8‐kb site or disruption of a GATA factor binding motif at the site was present in all Bm and ABm individuals examined. We investigated the molecular mechanism of the Am phenotype, which is analogous to the Bm phenotype.

Presence of nucleotide substitutions in transcriptional regulatory elements such as the erythroid cell-specific enhancer-like element and the ABO promoter in individuals with phenotypes A3 and B3, respectively

An erythroid cell‐specific regulatory element, referred to as the +5.8‐kb site, has been identified in the first intron of the human ABO blood group gene. Subsequent studies have revealed involvement of deletion or mutation at the site in phenotypes Am, Bm and ABm. We investigated the molecular mechanisms involved in the A3 and B3 phenotypes.

A 3·0-kb deletion including an erythroid cell-specific regulatory element in intron 1 of the ABO blood group gene in an individual with the Bm phenotype

We developed a sequence‐specific primer PCR (SSP‐PCR) for detection of a 5·8‐kb deletion (Bm5·8) involving an erythroid cell‐specific regulatory element in intron 1 of the ABO blood group gene. Using this SSP‐PCR, we performed genetic analysis of 382 individuals with Bm or ABm. The 5·8‐kb deletion was found in 380 individuals, and disruption of the GATA motif in the regulatory element was found in one individual. Furthermore, a novel 3·0‐kb deletion involving the element (Bm3·0) was demonstrated in the remaining individual. Comparisons of single‐nucleotide polymorphisms and microsatellites in intron 1 between Bm5·8 and Bm3·0 suggested that these deletions occurred independently.

Combination of postmortem mass spectrometry imaging and genetic analysis reveals very long-chain acyl-CoA dehydrogenase deficiency in a case of infant death with liver steatosis

CASE HISTORY A 3-month-old infant was found dead in his bed. A postmortem computed tomography (CT) scan suggested fatty attenuation in the liver parenchyma, but no other potentially fatal changes were found. To clarify the cause of death, a medicolegal autopsy was carried out. AUTOPSY FINDINGS Internal examination confirmed the presence of liver steatosis as well as hepatomegaly. There were no other significant findings including encephalitis or brain edema. MASS SPECTROMETRY ANALYSIS To clarify the mechanism underlying lipid accumulation in the liver, matrix-assisted laser desorption/ionization imaging mass spectrometry (MALDI-IMS) analysis was conducted. This indicated a significant accumulation of C14:1 acylcarnitine in the liver of the deceased, suggesting very long-chain acyl-CoA dehydrogenase (VLCAD) deficiency. GENETIC ANALYSIS To find the cause of the VLCAD deficiency, genetic analysis of the responsible gene, acyl-CoA dehydrogenase, very long chain (ACADVL), was performed. This revealed two novel mutations that may have accounted for the disease. CONCLUSION A combination of these data revealed that the liver steatosis in this case might have been caused by VLCAD deficiency based on genetic mutations of ACADVL. Thus, the deceased might have been vulnerable to energy crisis and sudden infant death. The present findings show that MALDI-IMS analysis as well as genetic analysis can be useful for elucidating the cause of death.

Postmortem computed tomography evaluation of fatal gas embolism due to connection of an intravenous cannula to an oxygen supply

An 84-year-old man who had suffered from chronic obstructive pulmonary disease accompanied by moderate pneumonia as well as gastric cancer with liver metastasis was found dead by a nurse, who noticed that the patients intravenous catheter in the left forearm had been erroneously connected to an oxygen supply in his hospital room, leading to infusion of oxygen into a vein. Postmortem CT scanning demonstrated multiple accumulations of gas in the pulmonary artery, the right atrium and ventricle, as well as the left subclavian and brachiocephalic veins, corresponding to the route that the infused gas would have taken to the heart and pulmonary artery. Conventional autopsy revealed the presence of gas in the right ventricle. These findings suggested that the immediate cause of death was a gas embolus due to oxygen that had entered the cardiopulmonary circulation via the intravenous catheter. This case highlights the usefulness of postmortem imaging as an aid to conventional autopsy for demonstrating gas embolism.

Blood group B gene is barely expressed in in vitro erythroid culture of Bm‐derived CD34+ cells without an erythroid cell‐specific regulatory element

Previously, a weak phenotype Am or Bm was assumed to be caused by a reduction of A or B gene expression in bone marrow cells, but not in mucus‐secreting cells. However, ABO expression has not been examined in erythroid progenitor cells of Am or Bm individuals.

ABO chimerism with a minor allele detected by the peptide nucleic acid-mediated polymerase chain reaction clamping method.

Discrepancy of results of ABO groups between red cell testing and serum testing is a significant issue in transfusion medicine1. One of its reported causes is blood chimerism, which shows mixed-field agglutination. However, mixed-field agglutination can be seen in various situations, including ABO-incompatible stem cell transplantation, recent transfusions of type-O red blood cells in a non-O recipient, and rare ABO subgroups such as B3 and chimera. Several molecular approaches have been employed to identify chimerism, namely ABO genotyping, human leucocyte antigen typing and DNA short tandem repeat assays2. These methods can typically detect three or more alleles of a chimera. However, some chimeras with a minor allele population might be overlooked because of preferential amplification of the major allele during ordinary polymerase chain reaction (PCR) analysis. We report a case of blood chimerism in which B red cells accounted for less than 1% of the whole population. The B allele in peripheral blood mononuclear cells could not be identified by direct sequencing of ordinary PCR product involving exons 6 and 7 of the ABO gene, but was revealed using peptide nucleic acid (PNA)-mediated PCR clamping.