Rhnull phenotype caused by a novel RHAG mutation, c.945+1G>A, in the Japanese population

BACKGROUND

The Rh complex contributes to cell membrane structural integrity of erythrocytes. Rh_null syndrome is characterized by the absence of the Rh antigen on the erythrocyte membrane, resulting in chronic hemolytic anemia. We recently came across 3 Rh_null phenotype probands within two families with the same novel RHAG mutation in the Japanese population.

MATERIALS AND METHODS

Detailed Rh phenotyping by hemagglutination was performed using monoclonal and polyclonal anti-D, -C, -c, -E, and -e; monoclonal and polyclonal anti-Rh17 antibodies; and polyclonal anti-Rh29 antibodies. RHAG mRNA transcripts were analyzed by reverse transcription-polymerase chain reaction, and the mutation was verified by genomic sequencing.

RESULTS

The genomic region spanning exon 6 contained a G > A transition in the invariant GT motif of the 5' donor splice-site of Intron 6 (c.945+1G>A). The Rh_null phenotype was caused by an autosomal recessive mutation in Probands 1 and 2, determined by family history. Regarding clinical features, the degree of hemolysis varied slightly between these individuals, with Proband 3 displaying acute hemolytic anemia with an infection. While no standard therapy has been established, the condition of the patient in this study improved with conservative treatment, including hydration and antibiotics.

CONCLUSION

The mechanisms of hemolysis due to the Rh_null phenotype can vary, but our findings indicate that acute hemolytic crisis caused by the Rh_null syndrome could be associated with infection.

Pathogenetic Analysis of Five Cases with a Platelet Disorder Characterized by the Absence of Thromboxane A2(TXA2)-Induced Platelet Aggregation in Spite of Normal TXA2 Binding Activity

Five patients with mild bleeding tendencies characterized by defective thromboxane A2 (TXA2)-induced platelet aggregation are reported. The platelets of all the patients had the ability to bind exogenous TXA2. Bleeding time was markedly prolonged in one patient. In three of the five patients, synthetic TXA2 mimetic (STA2)-induced platelet responses, including IP3 formation, Ca2+ mobilization, phosphatidic acid formation and GTPase activities were selectively defective, suggesting impaired coupling between the TXA2 receptor and phospholipase C activation. However, in the remaining two patients, these responses were all within normal limits. This suggests that the defective site of this type of platelet disorder is heterogenous and that signaling mechanisms other than the TXA2 receptor-phospholipase C pathway are also involved in TXA2-induced platelet aggregation.

[Myelodysplastic syndrome with refractory hemorrhage due to reduced platelet aggregation activity]

A 75-year-old woman suffered a cat bite 10 months after myelodysplastic syndrome (MDS) diagnosis. She visited our hospital because the internal bleeding of the wound did not improve. Although the wound was treated, the bleeding did not stop. She was hospitalized for emergency medical treatment because the bleeding volume exceeded 200 ml. Although her platelet count was normal, the platelet function test showed a decrease in collagen and arachidonic acid aggregation. After platelet transfusion, her bleeding stopped. Patients with MDS may potentially have platelet dysfunction. In the case of bleeding without thrombocytopenia, a platelet function test should be performed and treatment intervention, such as platelet transfusion, should be considered.

Mutations of the Platelet Thromboxane A2 (TXA2) Receptor in Patients Characterized by the Absence of TXA2–induced Platelet Aggregation despite Normal TXA2 Binding Activity

Previously, we reported five cases of platelet dysfunction characterized by the absence of thromboxane A2 (TXA2) – induced platelet aggregation despite normal TXA2 binding activity. In this platelet disorder, patients were divided into two groups; i.e. those whose platelets lacked or did not lack phospholipase C (PLC) activation (Group A and Group B, respectively) (Thromb Haemost 1996; 76: 1080). Furthermore, in one of the patients, we showed that a single amino acid substitution (Arg60 to Leu) in the first cytoplasmic loop of the TXA2 receptor (TXR) was responsible for this platelet disorder. However, mutational analysis of the TXR in the remaining patients has not been performed. Based on this background, we investigated the mutations of the TXR in these patients, and found that all of the patients have the same abnormality of the TXR (Arg60 → Leu), although the Group A patients were homozygous and the Group B patients were heterozygous for this mutation.

This mutation is the only abnormality which has been found in this platelet disorder, and in patients heterozygous for this mutation, the mutant type TXR suppresses wild-type receptor-mediated platelet aggregation by a mechanism independent of PLC activation.

Advanced glycation end products induce brain-derived neurotrophic factor release from human platelets through the Src-family kinase activation

Background

Brain-derived neurotrophic factor (BDNF) exerts beneficial effects not only on diabetic neuropathies but also on cardiovascular injury. There is argument regarding the levels of serum BDNF in patients with diabetes mellitus (DM). Because BDNF in peripheral blood is rich in platelets, this may represent dysregulation of BDNF release from platelets. Here we focused on advanced glycation end products (AGEs), which are elevated in patients with DM and have adverse effects on cardiovascular functions. The aim of this study is to elucidate the role of AGEs in the regulation of BDNF release from human platelets.

Methods

Platelets collected from peripheral blood of healthy volunteers were incubated with various concentrations of AGE (glycated-BSA) at 37 °C for 5 min with or without BAPTA-AM, a cell permeable Ca²⁺ chelator, or PP2, a potent inhibitor of Src family kinases (SFKs). Released and cellular BDNF were measured by ELISA and calculated. Phosphorylation of Src and Syk, a downstream kinase of SFKs, in stimulated platelets was examined by Western blotting and immunoprecipitation.

Results

AGE induced BDNF release from human platelets in a dose-dependent manner, which was dependent on intracellular Ca²⁺ and SFKs. We found that AGE induced phosphorylation of Src and Syk.

Conclusions

AGE induces BDNF release from human platelets through the activation of the Src-Syk-(possibly phospholipase C)-Ca²⁺ pathway. Considering the toxic action of AGEs and the protective roles of BDNF, it can be hypothesized that AGE-induced BDNF release is a biological defense system in the early phase of diabetes. Chronic elevation of AGEs may induce depletion or downregulation of BDNF in platelets during the progression of DM.

Electronic supplementary material

The online version of this article (doi:10.1186/s12933-017-0505-y) contains supplementary material, which is available to authorized users.

A short-term preservation of human cultured periosteal sheets, osteogenic grafting materials, using a commercial preservation solution containing epigallocatechin-3-gallate (Theliokeep(®)) under hypothermic conditions

In the past decade, it has increasingly been reported that epigallocatechin-3-gallate (EGCG), a major catechin derivative extracted from Green tea, has various bioactivities, including a cell-protective action on mammalian cells and tissues. In this study, we have tested a commercial preservation solution containing EGCG (Theliokeep(®)) in both two- and three-dimensional cultures of human periosteal sheets, which have been used as an osteogenic grafting material for periodontal regenerative therapy. When periosteal sheets were 3D-cultured on collagen mesh, cell viability was maintained for 2 days using the hypothermic EGCG preservation solution. Replenishment of EGCG solution with 2-day intervals prevented the time-dependent decline in cell viability at 3 days and later. As observed in nonpreserved control cultures, most cells were positive for proliferating cell-nuclear antigen (PCNA) in the cultures preserved at 4°C in the EGCG solution, whereas PCNA-negative cells were increased in the cultures preserved at 4°C in the MesenPRO medium. In periosteal sheets 2D-cultured in plastic dishes, the EGCG solution occasionally was associated with vacuole formation in the cytoplasm, but cells could again expand in the culture medium at 37°C. As observed in the nonpreserved periosteal sheets control, the osteogenic induction upregulated alkaline phosphatase in those cells and tissues preserved in the EGCG solution. The EGCG solution protected cells from the cold shock-induced membrane phospholipid peroxidation. Our data suggest that the EGCG solution acts as an antioxidant to protect periosteal cells from cold shock and preserves cells under chilled conditions. The limited period of preservation time could be expanded by repeating replenishment of the EGCG solution or by optimizing the formula to be more favorable for human periosteal sheets without sacrificing cell viability. This methodology of preserving human cultured periosteal sheets with EGCG would be expected to support and spread the clinical use of regenerative therapy with autologous periosteal sheets.

Late onset post-transfusion hepatitis E developing during chemotherapy for acute promyelocytic leukemia

We herein report the case of a leukemia patient who developed hepatitis E seven months after undergoing a transfusion with contaminated blood products. The latency period in this case was significantly longer than that of typical hepatitis E. Recently, chronic infection with hepatitis E virus (HEV) genotype 3 has been reported in immunocompromised patients. There is a possibility that our patient was unable to eliminate the virus due to immunosuppression following chemotherapy and the administration of steroids. The prevalence of HEV in healthy Japanese individuals is relatively high and constitutes a critical source of infection via transfusion. Hepatitis E is an important post-transfusion infection, and immunocompromised patients may exhibit a long latency period before developing the disease.

Successful treatment of severe newly diagnosed immune thrombocytopenia involving an alveolar hemorrhage with combination therapy consisting of romiplostim, rituximab and vincristine

A 51-year-old man was admitted due to a severe bleeding tendency. After he was diagnosed with immune thrombocytopenia (ITP), several therapies, including steroids, steroid pulse, vincristine and rituximab, were administered; however, the patient's bleeding symptoms were not sufficiently controllable with these treatments. Subsequently, a diffuse alveolar hemorrhage was observed. Treatment with a thrombopoietin receptor agonist, romiplostim, was initiated to prevent lethal hemorrhaging, although the efficacy of thrombopoietic receptor agonists in such emergency situations has not been elucidated. The initiation of romiplostim achieved prompt remission in platelets. This case suggests that combination therapy with romiplostim, rituximab and vincristine is effective in cases of newly diagnosed severe therapy-resistant ITP.

A clinical study of alveolar bone tissue engineering with cultured autogenous periosteal cells: coordinated activation of bone formation and resorption

In ongoing clinical research into the use of cultured autogenous periosteal cells (CAPCs) in alveolar bone regeneration, CAPCs were grafted into 33 sites (15 for alveolar ridge augmentation and 18 for maxillary sinus lift) in 25 cases. CAPCs were cultured for 6weeks, mixed with particulate autogenous bone and platelet-rich plasma, and then grafted into the sites. Clinical outcomes were determined from high-resolution three-dimensional computed tomography (3D-CT) images and histological findings. No serious adverse events were attributable to the use of grafted CAPCs. Bone regeneration was satisfactory even in cases of advanced atrophy of the alveolar process. Bone biopsy after bone grafting with CAPCs revealed prominent recruitment of osteoblasts and osteoclasts accompanied by angiogenesis around the regenerated bone. 3D-CT imaging suggested that remodeling of the grafted autogenous cortical bone particles was faster in bone grafting with CAPCs than in conventional bone grafting. The use of CAPCs offers cell-based bone regeneration therapy, affording complex bone regeneration across a wide area, and thus expanding the indications for dental implants. Also, it enables the content of particulate autogenous bone in the graft material to be reduced to as low as 40%, making the procedure less invasive, or enabling larger amounts of graft materials to be prepared. It may also be possible to dispense with the use of autogenous bone altogether in the future. The results suggest that CAPC grafting induces bone remodeling, thereby enhancing osseointegration and consequently reducing postoperative waiting time after dental implant placement.

Successful remission of Evans syndrome associated with Graves' disease by using propylthiouracil monotherapy

A 46-year-old woman with Graves' disease was admitted for anemia and thrombocytopenia. She had previously been treated with methimazole but she self-discontinued the treatment 6 months prior to admission. She was diagnosed with Evans syndrome associated with Graves' disease and treated with propylthiouracil without corticosteroids, which normalized her thyroglobulin level. Surprisingly, while Evans syndrome is characterized by frequent relapses, this patient has been in remission of Evans syndrome for approximately 4 years. The remission of Evans syndrome associated with Graves' disease in the absence of immunosuppressive therapy suggests that these 2 diseases have a common pathogenetic mechanism.

WT1 peptide vaccination in combination with imatinib therapy for a patient with CML in the chronic phase

Although tyrosine kinase inhibitors is effective for dramatically reducing CML cells, it might be difficult to eradicate completely the CML stem cells. We aimed to clarify the safety and effects of WT1 peptide vaccination in combination with imatinib therapy for a CML patient. A 51 year-old male with CML in CP, who showed a resistance against imatinib therapy for 2.5 years, began to be treated with 9 mer modified-type WT1 peptides in combination with standard dose of imatinib. Although every 2-week-administration of WT1 peptides for 22 weeks did not show definite effects on the quantification of bcr-abl transcripts, by changing the administration from every 2 weeks to 4 weeks bcr-abl transcripts decreased remarkably. After 11 months of every 4-week-administration of the peptides and 12 months post cessation of the peptides bcr-abl transcripts achieved to the level below detection by RQ/RT-PCR (complete molecular response). WT1/MHC tetramer(+)CD8(+) CTLs, which appeared after the second administration of WT1 peptides and remained more than 15 in number among 10(6) CD8(+) T cells throughout the administration of WT1 peptides, are still present in the blood on 14th month post cessation of the peptides. An in vitro study as to the cytotoxicity of lymphocytes induced by mixed lymphocyte peptide culture demonstrated that cultured lymphocytes possessed cytotoxicity against WT1 expressing leukemia cells and the cytotoxicity was WT1-specific and MHC class I restricted. The present study showed that WT1 peptide vaccination in combination with TKI is feasible and effective in the therapy for imatinib-resistant CML.

WT1 peptide vaccination in a CML patient: induction of effective cytotoxic T lymphocytes and significance of peptide administration interval

Although antigen-specific immune responses including cytotoxic T cells (CTLs) against antigen peptide could be enhanced after tumor antigen peptide vaccinations, the immune responses do not necessarily result in a decrease or eradication of tumor cells in the vaccination trials. We focused on whether antigen-specific CTLs could be damaged by the repeated stimulation of antigenic peptide and whether regulatory T (Treg) cells would be increased by the administration of WT1 peptide. We administered WT1 peptide 22 times over 18 months in a CML patient who was being treated with imatinib. Although WT1 peptide administration every 2 weeks did not show any beneficial effects on the minimal residual disease (copies of bcr-abl transcripts), the transcripts remarkably decreased to the level of major molecular response after changing the administration interval of WT1 peptide from 2 to 4 weeks. An ex vivo study demonstrated that re-stimulation with WT1 peptide made WT1-specific T cells less reactive to WT1 tetramers and the impaired reactivity of CTLs lasted at least for 1 week. In addition, the cytotoxicity of the T cells was hampered by re-stimulation. Treg cells increased up to more than fivefold at the end of the WT1 administration period. The present findings suggested that the administration of the peptide every 4 weeks is superior to every 2 weeks. In addition, the findings that Treg cells increased gradually in accordance with the duration of WT1 peptide administration revealed the significance of manipulating Treg cells for establishing an efficient tumor antigen peptide vaccination.

Inhibitory mechanism of human platelet aggregation by nafamostat mesilate

We found that nafamostat mesilate (NM) inhibits platelet aggregation induced by all agonists tested, including ADP, collagen, arachidonic acid, thromboxane A analog, A23187, phorbol 12-myristate 13-acetate (PMA), NaF and thrombin. The IC50 values were in the range of 9.3-17.8 microM. NM inhibited agonists-induced aspirin-treated platelet aggregation at >10 microM, suggesting that the action site lies beyond thromboxane (TXA)2 formation. However, NM inhibited thrombin (0.5 IU/ml)-induced TXB2 formation (IC50 = 1.9 +/- 0.6 microM, mean +/- SD). Intracellular Ca2+ mobilization was also inhibited only when platelets were challenged by thrombin, but the effect was found at NM concentrations >50 microM. This finding suggests that NM reduces the responses to thrombin by inhibiting its proteolytic activity on the platelet thrombin receptor (PAR1). NM did not affect the intracellular cAMP concentration or A-kinase activity. Agonists-induced surface expression of activated glycoprotein (GP)IIb-IIIa was inhibited by 10 microM NM and was completely inhibited by 50 microM NM. Since this inhibitory effect was parallel to the inhibition of platelet aggregation, the main inhibitory mechanism of NM against platelet aggregation seemed to be the suppression of activated GPIIb-IIIa expression, which makes it able to bind fibrinogen.

Combination use of immune complexes and a Ca2(+) channel blocker azelnidipine enhances interleukin-12 p40 secretion without T helper type 17 cytokine secretion in human monocyte-derived dendritic cells

Immune complexes (ICs) improve the capacity of priming specific CD8(+) cytotoxic T cell responses of dendritic cells (DCs). ICs induce phosphorylation of mitogen-activated protein kinases (MAPK) and calcium influx, although the precise regulating mechanism still remains unclear. In the present study, we investigated the effect of a Ca2(+) channel blocker on the phosphorylation of p38 MAPK and extracellular signal-regulated kinase (ERK) in immature monocyte-derived DCs stimulated with lipopolysaccharide (LPS) or LPS-ICs, and the production of interleukin (IL)-12 family members (p40, p70, IL-23), T helper type 17 (Th17) cytokines (IL-6 and IL-23), tumour necrosis factor (TNF)-alpha and IL-10 were also investigated. In comparison with LPS stimulation, LPS-ICs stimulation enhanced p38 MAPK phosphorylation significantly, which was associated with an increase in IL-12 p40 monomer/homodimer secretion. LPS-ICs also enhanced TNF-alpha and IL-6 secretion, but suppressed IL-23 secretion. The use of azelnidipine (Aze), a long-acting L-type Ca2(+) channel blocker with a high lipid solubility, suppressed p38 MAPK phosphorylation stimulated with LPS or LPS-ICs, but surprisingly enhanced IL-12 p40 monomer/homodimer secretion stimulated with LPS-ICs. This IL-12 p40 secretion-enhancing effect was not accompanied by IL-10 or IL-23 production, but was associated with ERK phosphorylation. The use of Aze did not affect IL-12 p70 production. These results suggest that the use of Aze enhances ICs-mediated IL-12 p40 secretion without additional IL-23 secretion. Therefore, the use of Aze and ICs could be a new therapeutic approach to immunomolecular therapy, as it does not cause Th17 differentiation which induces autoimmunity or reduces anti-tumour immunity.

A leukemic plasmacytoid dendritic cell line, PMDC05, with the ability to secrete IFN-alpha by stimulation via Toll-like receptors and present antigens to naïve T cells

We established a plasmacytoid dendritic cell (pDC) line (PMDC05) from leukemia cells of pDC leukemia. PMDC05 cells were positive for CD4, CD56, CD33, HLA-DR, CD123 (IL-3Ralpha) and CD86 in the absence of lineage markers. mRNA of TLR1, TLR2, TLR4, TLR7 and TLR9 was clearly expressed and among these TLRs, TLR7 was prominent. Production of IFN-alpha and IL-12 in PMDC05 was enhanced by the stimulation with CpG-A and LPS, respectively. PMDC05 possessed a considerable antigen presenting ability, which was enhanced by culturing with IL3, influenza virus or LPS. PMDC05 could be a useful tool for investigating the pathophysiology of pDCL.

Plasmacytoid dendritic cell leukemia with potent antigen-presenting ability

We report 2 patients with plasmacytoid dendritic cell leukemia (pDCL) expressing CD4, CD56, CD33, CD36, HLA-DR, CD123, CD86 and CD83 in the absence of lineage markers (myeloid, B, T or natural killer cells) except for CD33. Culturing leukemic blasts of both cases with IL-3 for 4 days increased the expression of surface molecules associated with antigen presentation, e.g. CD1a and CD40. Leukemic blasts of both cases possessed a considerable level of antigen-presenting ability to allogeneic lymphocytes in mixed leukocyte cultures. Culturing the blasts with IL-3 for 4 days markedly increased allogeneic antigen presenting ability. Combined with data showing evident graft-versus-leukemia effects without graft-versus-host disease in a cord blood stem cell transplanted pDCL case, leukemic cells in pDCL may act as potent antigen presenting cells in vivo, too.

Inhibitory effects of the antiepileptic drug ethosuximide on G protein-activated inwardly rectifying K+ channels

Antiepileptic drugs protect against seizures by modulating neuronal excitability. Ethosuximide is selectively used for the treatment of absence epilepsy, and has also been shown to have the potential for treating several other neuropsychiatric disorders in addition to several antiepileptic drugs. Although ethosuximide inhibits T-type Ca(2+), noninactivating Na(+), and Ca(2+)-activated K(+) channels, the molecular mechanisms underlying the effects of ethosuximide have not yet been sufficiently clarified. G protein-activated inwardly rectifying K(+) channels (GIRK, or Kir3) play an important role in regulating neuronal excitability, heart rate and platelet aggregation. In the present study, the effects of various antiepileptic drugs on GIRK channels were examined first by using the Xenopus oocyte expression assay. Ethosuximide at clinically relevant concentrations inhibited GIRK channels expressed in Xenopus oocytes. The inhibition was concentration-dependent, but voltage-independent, and time-independent during each voltage pulse. However, the other antiepileptic drugs tested: phenytoin, valproic acid, carbamazepine, phenobarbital, gabapentin, topiramate and zonisamide, had no significant effects on GIRK channels even at toxic concentrations. In contrast, Kir1.1 and Kir2.1 channels were insensitive to all of the drugs tested. Ethosuximide also attenuated ethanol-induced GIRK currents. These inhibitory effects of ethosuximide were not observed when ethosuximide was applied intracellularly. In granule cells of cerebellar slices, ethosuximide inhibited GTPgammaS-activated GIRK currents. Moreover, ADP- and epinephrine-induced platelet aggregation was inhibited by ethosuximide, but not by charybdotoxin, a platelet Ca(2+)-activated K(+) channel blocker. These results suggest that the inhibitory effects of ethosuximide on GIRK channels may affect some of brain, heart and platelet functions.

Enhancement of anti-tumor cytotoxicity of expanded gammadelta T Cells by stimulation with monocyte-derived dendritic cells

In order to establish the method of generating powerful gammadelta T cells for anti-tumor immunotherapy, we investigated the effects of monocyte-derived dendritic cells (mo-DCs) on anti-tumor cytotoxicity of expanded gammadelta T cells. Activation of gammadelta T cells co-cultured for 2-3 days with immature or mature mo-DCs was evaluated by CD69 expression and anti-tumor cytotoxicity using two assays : the 5- (and 6-) carboxyfluorescein diacetate, succinimidyl ester-based cytotoxicity assay and the calcein-AM-based Terascan assay. gammadelta T cells were used as effector cells and myeloma cell line (RPMI8226) or chronic myelogenous leukemia blastic crisis cell line (C2F8) were used as target cells. CD69 expression on gammadelta T cells was enhanced by co-culture with both immature and mature mo-DCs in a cell-number-dependent fashion. CD69 expression was enhanced after addition of mo-DCs of either autologous or allogeneic origin. Activation of gammadelta T cells with mo-DCs enhanced anti-tumor cytotoxicity of gammadelta T cells against RPMI8226 and C2F8 in an effector-to-target ratio-dependent manner. Activation of gammadelta T cells by mo-DCs was associated with the enhancement of anti-tumor cytotoxicity of gammadelta T cells. Potent gammadelta T cells activated by mo-DCs were considered to be applicable to an efficient gammadelta T cell-mediated immunotherapy for tumors.

Plasma brain natriuretic peptide during myeloablative stem cell transplantation

OBJECTIVE

Cardiovascular complication is one of the serious complications in stem cell transplantation (SCT). We measured plasma brain natriuretic peptide (BNP) concentrations in patients who received SCT to evaluate possible cardiac toxicity of the regimens employed in SCT.

PATIENTS

Ten patients with allogeneic SCT and 5 patients with autologous SCT using myeloablative conditioning regimens were enrolled. The preparative chemotherapy for 8 patients with allogeneic SCT included cyclophosphamide (60 mg/kg i.v. for 2 days) and other drugs and that for autologous SCT included cyclophosphamide (50 mg/kg for 2 days) and other drugs. Total body irradiation (TBI) was employed only in the patients who received allogeneic SCT.

METHOD

Plasma BNP was measured using a radioimmunoassay for human BNP before and after SCT.

RESULTS

In 13 of 15 patients, BNP levels were elevated after SCT. In patients who received a total body irradiation (TBI) of 13.2 Gy, BNP levels were higher than those without irradiation (p=0.01). The BNP level reached a peak within 6 months after SCT in most patients and fell thereafter. But 7 of the 15 patients (46.7%) had an abnormally high level of plasma BNP even after 6 months of SCT which suggests subclinical myocardial damage.

CONCLUSION

A rise in plasma BNP was frequently observed after SCT, and may be considered to represent cardiac damage caused by the preparative chemotherapy and/or total body irradiation. Since a rise was noted 6 months after SCT, long-term evaluation of cardiac function is important.

In vitro effect of cyclosporin A, mitomycin C and prednisolone on cell kinetics in cultured human umbilical vein endothelial cells

INTRODUCTION

Vascular endothelial cell damage plays an important role in microvascular thrombogenesis. In vivo administration of cyclosporin A or mitomycin C sometimes results in thrombotic microangiopathy in patients.

MATERIALS AND METHODS

The effects of cyclosporin A, mitomycin C and/or prednisolone on the cell cycle in cultured human umbilical vein endothelial cells were investigated to evaluate drug-induced endothelial cell damage and the protective effect of prednisolone on endothelial cells against the damage by cyclosporin A or mitomycin C in vitro.

RESULTS

The addition of cyclosporin A to cultures caused proliferation arrest in the G1-phase in a dose-dependent manner, while mitomycin C inhibited DNA synthesis, which resulted in cell cycle arrest and inhibition of BrdUrd incorporation in the S-phase. The administration of prednisolone also caused cell cycle arrest in the G1 by itself, and protected the cells from the damage caused by mitomycin C. The inhibitory effects of cyclosporin A and prednisolone on the cell cycle were reversible, while mitomycin C was not. The highly phosphorylated retinoblastoma protein expressed in human umbilical vein endothelial cells decreased in the presence of mitomycin C. Soluble thrombomodulin levels in the culture supernatant were elevated by the addition of cyclosporin A.

CONCLUSION

These effects of the drugs may cause the cell cycle arrest and the prolonged repair of damaged endothelial cells in patients.

High-dose cytosine arabinoside and etoposide with total body irradiation as a preparatory regimen for allogeneic hematopoietic stem-cell transplantation in patients with acute lymphoblastic leukemia

One approach to improving the outcome of allogeneic hematopoietic stem-cell transplantation for acute lymphoblastic leukemia (ALL) is to intensify the pretransplant conditioning regimen without increasing toxicity. We used an intensified conditioning regimen consisting of high-dose cytosine arabinoside (3 g/m(2) twice daily i.v. for 3 consecutive days, total six doses), high-dose etoposide (1 g/m(2) once daily i.v. during the first 2 days) and total body irradiation (TBI) (HDACE-TBI) in ALL patients. We retrospectively analyzed 21 patients treated with HDACE-TBI, of whom 18 were in complete remission (CR) and three were in non-CR at transplantation. Although gastrointestinal toxicities were common, critical regimen-related toxicities were not seen in any patients. One patient demonstrated veno-occlusive disease, which could be controlled conservatively. The disease-free survival rate of 18 patients in CR at transplantation was 61%. These results demonstrate that the HDACE-TBI combination regimen is a feasible alternative to other preparatory regimens and does not increase the regimen-related toxicity.

DDAVP normalized the bleeding time in patients with congenital platelet TxA2 receptor abnormality

BACKGROUND

An Arg60-to-Leu mutation was found in the first cytoplasmic loop of the PLT TxA2 receptor as a new congenital PLT disorder characterized by impaired responsiveness to TxA2. However, it has not been clarified whether DDAVP is effective in correcting the bleeding time (BT) in this PLT disorder.

STUDY DESIGN AND METHODS

DDAVP (0.4 microg/kg) was intravenously administered over 20 minutes in five patients with this PLT disorder, and template BT, PLT retention to glass beads, PLT aggregation, and a coagulation study were performed before and after the infusion of DDAVP. PLT TxA2 synthesis defects (cyclo-oxygenase deficiency, volunteers taking aspirin), thrombasthenia, and Bernard-Soulier syndrome were also included in this study.

RESULTS

The normalization of BT was found in all patients with this PLT disorder, and one of the patients successfully underwent oral surgical procedures with DDAVP as the only hemostatic agent. DDAVP was also efficacious in the TxA2 synthesis defect but not in other disorders. FVIII coagulation activity, vWF antigen, and ristocetin cofactor significantly increased in all patients after DDAVP, but no changes were seen in the PLT retention rate and PLT aggregation study after DDAVP infusion.

CONCLUSION

DDAVP was effective in correcting BT in patients with impaired responsiveness to TxA2 as well as impaired production of TxA2.

Long-term production of pre-existing alloantibodies to E and c after allogenic BMT in a patient with aplastic anemia resulting in delayed hemolytic anemia

BACKGROUND

Delayed hemolysis mediated by long-term production of pre-existing recipient-derived antibodies directed against donor RBC antigens after allogenic BMT is an unusual complication of hematopoietic transplantation.

CASE REPORT

A 26-year-old man with aplastic anemia had pre-existing alloantibodies to E and c. He received BMT from a donor, whose Rh phenotype was E+, c+. From about 1 month after the transplant, he showed mild hemolysis due to the antibodies.

RESULTS

The patient was typed as group B, CCDee and had anti-E and c alloantibodies before BMT. The donor was typed as group O, ccDEE. Although MNCs from the donor marrow were infused into the patient, DAT became positive on Day 21, and the patient-origin antibodies remained detectable by both DAT and IAT even 20 months after BMT. However, immunomagnetically isolated peripheral circulating B cells were 100 percent donor origin. The patient received prednisolone from Day 221, and thereafter, the signs of hemolysis disappeared.

CONCLUSION

It is likely that the long-term production of alloantibodies is due to the existence of long-lived recipient plasma cells, which survive the conditioning regimen. This case suggests that patients with pre- existing alloantibodies that do not belong to the ABO system should be carefully followed up after BMT.

Acute pulmonary thromboembolism induced by prophylactic heparin use and a heparin-coated catheter: a case of heparin-induced thrombocytopenia and thrombosis syndrome

Heparin-induced thrombocytopenia and thrombosis syndrome (HITTS) is a potentially life-threatening side effect of heparin therapy, triggered by an immune response, and has been reported to be related not only to the therapeutic use of heparin but also to heparin-coated catheters. A 45-year-old woman with intrapelvic malignancy developed an acute pulmonary thromboembolism (PE) after hysterectomy despite prophylactic heparin use. Subsequent large doses of heparin for treatment of the PE exacerbated the thrombocytopenia and, moreover, a large thrombus formed around the heparin-coated central venous catheter. Anti-heparin-platelet factor 4 complex antibody and heparin-induced platelet aggregation assay were positive, so the diagnosis was HITTS, and heparin was replaced by argatroban after carrying out thrombectomy. This therapy was successful, and the patient made favorable progress.

Acquired factor V inhibitor complicated by Hashimoto's thyroditis, primary biliary cirrhosis and membranous nephropathy

A 59-year-old man diagnosed as having Hashimoto's thyroditis, primary biliary cirrhosis (PBC) and membranous nephropathy (MN) showed consciousness disturbance, convulsions of the upper part of his body, and rapid progression of anemia, which seemed to be derived from subdural and retroperitoneal hemorrhage, respectively. He had been diagnosed as having eosinophilia about 6 weeks before the attack. Coagulation tests revealed a prolonged activated partial thromboplastin time and prothrombin time, which could not be normalized by mixing with normal plasma. Factor V (FV) activity was severely decreased and the purified immunoglobulin G of the patient inhibited normal plasma FV activity in a dose-dependent manner, suggesting the presence of antibody-mediated circulating inhibitors specific for FV. Treatment with steroids and azathioprine as well as plasmapheresis led to improvement of his clinical symptoms, normalization of the coagulation tests, and disappearance of eosinophilia. However, the inhibitor reappeared about 7 months later in association with eosinophilia, which was also improved by steroid therapy. To our knowledge, this is the first report of the co-existence of these three kinds of immune-mediated disorders, and the first report concerning the association between acquired FV inhibitors and PBC with MN. A new unknown immune mechanism, which causes eosinophilia, may be involved in the development of the FV inhibitor in this patient.

High-dose chemotherapy and autologous peripheral blood stem cell transplantation for treatment of unspecified peripheral T-cell lymphoma presented with hepatosplenomegaly and hypercytokinemia syndrome: report of three cases

We report here three cases of peripheral T-cell lymphoma unspecified (PTCL-US), which presented with bone marrow infiltration and hepatosplenomegaly and were successfully treated with high-dose chemotherapy (HDCT) and autologous peripheral blood stem cell transplantation (auto-PBSCT). The patients were all characterized by cytokine-induced symptoms such as fever, anasarca, cytopenia, poor general condition, and disseminated intravascular coagulation syndrome. Laboratory data showed extremely high levels of soluble interleukin-2 receptor, beta(2)-microglobulin, and ferritin. All three patients were negative for anti-adult T-cell leukemia antibody. In one patient, hemophagocytosis was revealed by a histological examination of the bone marrow. The International Prognostic Index was high for all three patients, and they all achieved complete remission after the intensive chemotherapy for remission induction. During complete remission, they were treated with HDCT [modified interleukin-converting enzyme regimen] followed by auto-PBSCT. The recovery of hematopoiesis after auto-PBSCT was prompt and sustained engraftment was obtained. No serious adverse effects other than myelosuppression were noted. One patient died due to cerebrovascular disease without relapse 18 months after auto-PBSCT. The other two patients are still alive and have not suffered from relapse. Our observations suggest that auto-PBSCT following HDCT may be an effective and safe therapeutic modality for high-risk PTCL-US patients characterized by hepatosplenomegaly and cytokine-induced syndrome.

Acute promyelocytic leukemia developing in untreated essential thrombocythemia

We describe a patient with untreated essential thrombocythemia (ET) who developed microgranular variant of acute promyelocytic leukemia, 9 years after the initial diagnosis of ET. He achieved complete remission (CR) but relapsed 11 months later. After achieving the second CR, he received peripheral stem cell transplantation from his HLA complete-matched sibling. Five months after the transplantation, he relapsed again with meningeal infiltration of leukemic cells. In this paper, we review cases of promyelocytic transformation of myeloproliferative diseases (MPD) other than chronic myeloid leukemia (CML). To our knowledge, this is the first case of promyelocytic transformation of Philadelphia chromosome negative untreated ET, in whom both t(15;17) and PML-RAR alpha fusion were proven.

Induction and characterization of cutaneous lymphocyte antigen on natural killer cells

Cutaneous lymphocyte antigen (CLA) has been reported to be expressed mainly by memory/effector T lymphocytes infiltrating inflammatory skin lesions and cutaneous T-cell lymphoma. It has been suggested that CLA is a specific homing receptor, facilitating the T-cell migration into skin lesions, and also an indicator of the skin-homing T-cell subset. In the present study, we investigated the expression of CLA in natural killer (NK) cells defined phenotypically as surface CD3- and CD56+ cells in peripheral blood. CLA was definitely expressed on CD3-CD56+ cells at a level comparable to CD3+ cells in peripheral blood of normal Japanese volunteers. After in vitro stimulation of peripheral blood mononuclear cells with interleukin 2 (IL-2) and IL-12, there was a significant increase in the number and percentage of CLA+ NK cells but not CLA+ T cells (P < 0.01). To analyse the characteristics of CLA expressed by NK cells, we investigated a CLA+ NK-leukaemia cell line, NK-YS, established from a patient with NK leukaemia/lymphoma with skin infiltration. In the in vitro study, the CLA-expressing NK-leukaemic cell line bound to E-selectin-transfected cells and was inhibited by HECA 452 antibody or neuraminidase treatment of leukaemic cells. These findings suggest that CLA expressed by NK cells is a homing receptor for the E-selectin molecule and may explain skin infiltration by NK cells and NK lymphoma cells analogous to T cells. An NK-cell subset expressing CLA must play an important role in host defence against microorganisms and neoplasms in skin lesions.

Bone marrow necrosis with dyspnea in a patient with malignant lymphoma and plasma levels of thrombomodulin, tumor necrosis factor-alpha, and D-dimer

Non-Hodgkin's lymphoma (peripheral T cell, unspecified, clinical stage IIIEA) was diagnosed in a 54-year-old male. He was treated weekly with chemotherapy consisting of pirarubicin hydrochloride, cyclophosphamide, methotrexate, vincristine sulfate, etoposide, and prednisolone. After 6 weeks of treatment in a state of partial remission, he exhibited sudden dyspnea, chest pain, fever, and drowsiness. The patient had received 100 microg/day of granulocyte colony stimulating factor (G-CSF) for 6 days before the onset. Laboratory data showed an elevated lactate dehydrogenase (LDH) level, leukoerythroblastosis in the peripheral blood, and no decrease in the serum haptoglobin level. There were no findings of acute myocardial infarction or pulmonary thromboembolism. Bone marrow specimen showed the characteristic features of necrosis without any signs of the involvement of lymphoma cells. No indications of infections were found. This patient was diagnosed as having bone marrow necrosis (BMN) during the recovery phase of bone marrow with G-CSF treatment after chemotherapy for malignant lymphoma. After conservative therapy, inhalation of oxygen and stopping the administration of G-CSF, all clinical symptoms subsided except that the elevation of LDH continued for 1 month. The plasma level of tumor necrosis factor-alpha (TNF-alpha) was high just after the onset of BMN. The thrombomodulin (TM) level was high just before the onset of BMN and continued to be high for 2 weeks. Cross-linked fibrin degradation products (D-dimer) were also high just after the onset of BMN and continued to be high for 3 weeks after the onset. Although dyspnea is a rare symptom of BMN, it is important to rule out in BMN during the recovery phase of bone marrow with G-CSF treatment after chemotherapy for malignant lymphoma. Activated neutrophils in the small vessels of the lung by G-CSF and microthrombi, suggested by the elevation of D-dimer, may participate in the onset of dyspnea, which is a rare symptom of the onset of BMN.

Lymphomatous polyp of mantle cell type in the duodenum complicated by gastric cancer: a case of trisomy 3 and t(11;14)(q13;q32)

We experienced a rare case of a lymphomatous polyp of mantle cell type forming a polypoid mass lesion in the duodenum bulbous together with advanced gastric cancer. A total gastrectomy was performed, and the specimen revealed atypical small- to medium-sized lymphoid cells with indented nuclei, which infiltrated the Peyer's patch and formed a nodular mass in the lamina propria and submucosa of the duodenum. The lymphoma cells also infiltrated the lymphoid follicle of the gastric mucosa, spleen, and regional lymph node with a typical mantle zone pattern. Flow cytometric analysis of the single cells of the lymph node and immunohistochemistry of a paraffin-embedded specimen revealed that the lymphoma cells expressed surface CD5, CD19, CD20, and nuclear cyclin D1. Chromosomal analysis of this single cell suspension revealed that these lymphoma cells have trisomy 3 in conjunction with t(11;14)(q13;q32), which is frequently seen in mucosa-associated lymphoid tissue lymphomas (MALToma) in the stomach and is also reported in mantle cell lymphoma as a secondary genetic alteration. Our report suggests that trisomy 3 may be a common chromosomal abnormality in lymphomatous polyps of mantle cell type.

Combined Ala601-Thr-type dysplasminogenaemia and antiphospholipid antibody syndrome in a patient with recurrent thrombosis

A 44-year-old man was admitted to our hospital because of recurrent thrombosis. Laboratory findings showed that he had antiphospholipid antibody syndrome (APS) associated with systemic lupus erythematosus. Plasminogen activity was reduced (21%), but its antigenic level was rather elevated (16.4 mg/dl). The discrepancy of plasminogen activity and antigen levels was also found in his three daughters. Gene analysis revealed a homozygous missense mutation (Ala601-->Thr) at exon 15 of the plasminogen gene in the patient and a heterozygous mutation in his three daughters, suggesting that the patient has dysplasminogenaemia, which was reported as "plasminogen Tochigi." Although it still remains controversial whether both dysplasminogenaemia and plasminogen deficiency are relevant independent thrombotic risk factors, the combination of this deficiency and APS should be considered as a strong predisposition to thrombosis in this patient.

Difference in CD22 molecules in human B cells and basophils

OBJECTIVE

CD22 is believed to be restricted to normal and neoplastic B cells. Human basophils were found to express CD22 molecules. Among the antibodies against CD22, Leu14, which recognized the ligand binding domain, reacted to basophils, and B3 and 4KB128, which recognized the amino terminus side and carboxy terminus side of the ligand binding epitope, respectively, did not. To clarify the difference of CD22 antigenicity in human B cells and basophils, we investigated RNA sequence and structures of CD22 molecules.

MATERIALS AND METHODS

Purified B cells and basophils were obtained from normal human volunteers by using a MACS magnetic cell sorting system and anti-CD19 and anti-Fc epsilon R1 antibodies, respectively. RT-PCR and sequencing of CD22 mRNA were performed in the exons 3 to 8. Western blotting analysis of CD22 was also performed.

RESULTS

The sequence of CD22 mRNA extracted from the basophils was the same as that of B cells in exons 3 to 8 (epitopes recognized by Leu14, B3, and 4KB128 were translated from exons 4 and 5). Reduced CD22 peptide extracted from the basophils reacted to Leu14 as well as B3 and 4KB128, and the molecular size of the reduced and nonreduced products was 130 kDa as expected.

CONCLUSION

Disulfide bonds and the resulting 3D conformation of the CD22 molecules may have important roles in the difference of antigenicity of CD22 beta in B cells (CD22 beta 1) and basophils (CD22 beta 2). The difference in molecular structure surrounding the ligand-binding domain of CD22 may imply a specialization of the conformational forms of CD22 according to the ligand isoforms.

Generation of functional and mature dendritic cells from cord blood and bone marrow CD34+ cells by two-step culture combined with calcium ionophore treatment

The object of this study is to explore a culture method to generate a large number of functional and mature dendritic cells (DC) from human CD34+ hematopoietic progenitor cells. In the present study, we used a two-step method combined with calcium ionophore to induce DC from cord blood (CB) or normal human bone marrow (BM) CD34+ progenitor cells. The two-step method consists of 10 days of first step culture for the expansion and proliferation of CD34+ hematopoietic progenitor cells in the presence of SCF, IL-3, IL-6, G-CSF, and 7--11 days of second step culture for the induction of DC in the presence of GM-CSF, IL-4 and TNF-alpha. By the two-step culture, total nucleated cells were increased 208+/-66 (+/-SD, n=13), or 94+/-29 (n=5)-fold in the culture of CB or BM cells, respectively, compared with the number of CD34+ cells at the time of starting culture. Out of the total nucleated cells, 23 +/-10.4% of cells in CB cell culture and 25 +/-5% of cells in the BM cell culture acquired DC characteristic phenotypes, which were marked expressions of CD1a, HLA-DR, co-stimulatory molecules such as CD80, CD40, and adhesion molecule such as CD58. In allogeneic mixed leukocyte reaction (MLR), two-step cultured cells showed potent allo-stimulatory capacity. With this two-step culture, the absolute number of CD1a+ cells that co-expressed HLA-DR, CD80, CD40 and CD58 was enhanced approximately 3 times in CB cell culture and 1.9 times in BM cell culture, compared with the commonly used one-step culture method for the generation of DC from CD34+ cells using SCF, GM-CSF and TNF-alpha. However, on these DC generated in the two-step culture, the expressions of co-stimulatory molecule CD86 and mature DC marker CD83 were not sufficient. By the treatment of two-step cultured cells with calcium ionophore agent (A23187), the expression of co-stimulatory molecules such as CD86 and CD80 (especially CD86) was up-regulated. Besides, the expression of mature DC marker CD83 was remarkably induced by treatment with A23187 for a short duration (24 h). Consistent with the up-regulation of surface molecules CD86, CD80 and CD83, the two-step cultured cells treated with A23187 also showed a stronger allo-stimulatory capacity compared with the cells without A23187 treatment. In conclusion, the present study demonstrated that the two-step culture method effectively improved the yield of CD1a+ DC generated from CD34+ cells, and the phenotypes and functions of these CD1a+ DC could be enhanced efficiently by treatment with a calcium ionophore agent.

Levels of soluble E-selectin and ICAM-1 in the coronary circulation of patients with stable coronary artery disease: association with the severity of coronary atherosclerosis

The recruitment of circulating leukocytes to atherosclerotic sites is mediated by a family of adhesion molecules. The objective of the present study was to evaluate the relationship between circulating adhesion molecule levels in the coronary circulation and the severity of coronary atherosclerosis in patients with stable coronary artery disease. The subjects were 79 patients undergoing coronary angiography. According to the severity of coronary atherosclerosis as assessed by the Gensini Score (GS) of the left coronary artery, they were classified into three groups: group C (no organic stenosis, score 0, n = 14), group M (mild organic stenosis, score 1-13, n = 39) and group S (severe organic stenosis, score > or = 14, n = 26). Blood samples were taken from the aorta (Ao) and coronary sinus (CS), and plasma levels of soluble E-selectin (sE-selectin) and soluble intercellular adhesion molecule-1 (sICAM-1) were measured by enzyme-linked immunosorbent assay. These levels were then compared between groups. There were no significant differences in plasma sICAM-1 levels in the Ao or CS between the three groups. The difference in sICAM-1 levels between the CS and Ao (CS-Ao) also showed no significant difference. Plasma sE-selectin levels in both the Ao and CS were significantly higher in group S than in groups C and M (p < 0.05), but there were no significant differences in CS-Ao. There was a weak but significant correlation between the plasma levels of these adhesion molecules and the number of coronary risk factors present. Multivariate analysis showed that the number of coronary risk factors was the only positive predictor (p = 0.0048) of the GS; there was no association between the plasma level of either adhesion molecule and the GS. In patients with stable coronary artery disease, sICAM-1 plasma levels do not indicate the severity of coronary atherosclerosis, while sE-selectin plasma levels appear to reflect the severity of systemic rather than coronary atherosclerosis.

A female with asymptomatic primary biliary cirrhosis associated with pernicious anemia

We experienced a female case with asymptomatic primary biliary cirrhosis that was associated with pernicious anemia after 16 years from the onset. She was 52 years old when she first visited a clinic in 1981 for liver dysfunction treatment. Antimitochondrial antibody was negative and antipyruvate dehydrogenase complex antibody was positive in a low titer in its immunoglobulin (Ig)M type. Histological examination of her liver revealed a presence of definite chronic non-suppurative destructive cholangitis with numerous epithelioid cell granuloma. She had been given 600 mg of the oral daily dose of ursodeoxycholic acid since 1992. Macrocytic anemia incidiously appeared in September 1999. An immunological examination detected negative antiparietal cell antibodies and positive anti-intrinsic factor antibodies. Her bone marrow smear showed numerous megaloblasts and serum vitamin B12 in her blood was low at 99 pg/mL. Severe reversed atrophic-type gastritis (type A gastritis) was demonstrated by the use of dye-endoscopy with Congo red. Her macrocytic anemia dramatically improved after intramuscular administration of vitamin B12. In conclusion, attention should be given to the association of pernicious anemia during the follow up of primary biliary cirrhosis.

Erythroid involvement in CD36 deficiency

OBJECTIVE

The CD36 molecule is expressed in platelets, monocytes, erythroblasts, and other different tissues. The two types of platelet CD36 deficiency, types I and II, are associated with the absence and presence of CD36 on monocytes, respectively. To clarify the involvement of the erythroid lineage in CD36 deficiency, we investigated the phenotype and RNA expression of CD36.

MATERIALS AND METHODS

CD36 expression was examined in 296 patients with several cardiovascular diseases in our outpatient clinic. There were 12 patients with type I deficiency and 16 with type II CD36 deficiency. A bone marrow sample was examined in five type I and four type II patients. Expression of CD36 mRNA was examined in burst-forming unit-erythroid (BFU-E). The sequences of reverse transcriptase polymerase chain reaction (RT-PCR) products of the CD36 mRNA from monocytes were examined.

RESULTS

As expected, CD36 was deficient in erythroblasts from all five patients with type I deficiency. CD36 was present in erythroblasts from three of the four with type II deficiency, suggesting that their abnormality is restricted to platelets (type IIa). CD36 was unexpectedly absent from erythroblasts of a single type II patient (type IIb). CD36-specific mRNA was identified in BFU-E from each of two normals, six type I, and six type II patients, including type IIb. The sequences of RT-PCR products of the CD36 mRNA in a patient with type IIa and another with type IIb showed homozygous wild alleles.

CONCLUSION

The findings provide evidence for further heterogeneity among CD36-deficient individuals and the existence of a basic principle mechanism of type II, such as glycosylation abnormality.

Arg60 Leu mutation in the first cytoplasmic loop of the platelet thromboxane A2 receptor is not essential for mediating inhibitory coupling between the receptor and adenylyl cyclase

Human platelet thromboxane A2 (TXA2) receptor (TXR) has been reported to functionally couple to the inhibitory GTP-binding protein for adenylyl cyclase (Gi). However, it still remains unclear which portions of the TXR structure are critical determinants in that coupling. We have previously reported several patients with platelet dysfunction, whose platelets showed impaired coupling between TXR and phospholipase C caused by an Arg60 to Leu mutation in the first cytoplasmic loop. To investigate whether this portion is essential for mediating inhibitory coupling between TXR and adenylyl cyclase, we analyzed the inhibition by the TXA2 analog of the PGE1 or forskolin-induced platelet cAMP increase in patients' platelets, and found that the inhibition occurred normally. This suggests that Arg60 in the first cytoplasmic loop of the TXR is not involved in TXR-Gi coupling.