Genetically corrected RAG2-SCID human hematopoietic stem cells restore V(D)J-recombinase and rescue lymphoid deficiency

ABSTRACT

Recombination-activating genes (RAG1 and RAG2) are critical for lymphoid cell development and function by initiating the variable (V), diversity (D), and joining (J) (V(D)J)-recombination process to generate polyclonal lymphocytes with broad antigen specificity. The clinical manifestations of defective RAG1/2 genes range from immune dysregulation to severe combined immunodeficiencies (SCIDs), causing life-threatening infections and death early in life without hematopoietic cell transplantation (HCT). Despite improvements, haploidentical HCT without myeloablative conditioning carries a high risk of graft failure and incomplete immune reconstitution. The RAG complex is only expressed during the G0-G1 phase of the cell cycle in the early stages of T- and B-cell development, underscoring that a direct gene correction might capture the precise temporal expression of the endogenous gene. Here, we report a feasibility study using the CRISPR/Cas9-based "universal gene-correction" approach for the RAG2 locus in human hematopoietic stem/progenitor cells (HSPCs) from healthy donors and RAG2-SCID patient. V(D)J-recombinase activity was restored after gene correction of RAG2-SCID-derived HSPCs, resulting in the development of T-cell receptor (TCR) αβ and γδ CD3+ cells and single-positive CD4+ and CD8+ lymphocytes. TCR repertoire analysis indicated a normal distribution of CDR3 length and preserved usage of the distal TRAV genes. We confirmed the in vivo rescue of B-cell development with normal immunoglobulin M surface expression and a significant decrease in CD56bright natural killer cells. Together, we provide specificity, toxicity, and efficacy data supporting the development of a gene-correction therapy to benefit RAG2-deficient patients.

Genome engineering with Cas9 and AAV repair templates generates frequent concatemeric insertions of viral vectors

CRISPR-Cas9 paired with adeno-associated virus serotype 6 (AAV6) is among the most efficient tools for producing targeted gene knockins. Here, we report that this system can lead to frequent concatemeric insertions of the viral vector genome at the target site that are difficult to detect. Such errors can cause adverse and unreliable phenotypes that are antithetical to the goal of precision genome engineering. The concatemeric knockins occurred regardless of locus, vector concentration, cell line or cell type, including human pluripotent and hematopoietic stem cells. Although these highly abundant errors were found in more than half of the edited cells, they could not be readily detected by common analytical methods. We describe strategies to detect and thoroughly characterize the concatemeric viral vector insertions, and we highlight analytical pitfalls that mask their prevalence. We then describe strategies to prevent the concatemeric inserts by cutting the vector genome after transduction. This approach is compatible with established gene editing pipelines, enabling robust genetic knockins that are safer, more reliable and more reproducible.

IDH1-mutant preleukemic hematopoietic stem cells can be eliminated by inhibition of oxidative phosphorylation

Rare preleukemic hematopoietic stem cells (pHSCs) harboring only the initiating mutations can be detected at the time of AML diagnosis. pHSCs are the origin of leukemia and a potential reservoir for relapse. Using primary human samples and gene-editing to model isocitrate dehydrogenase 1 (IDH1) mutant pHSCs, we show epigenetic, transcriptional, and metabolic differences between pHSCs and healthy hematopoietic stem cells (HSCs). We confirm that IDH1 driven clonal hematopoiesis is associated with cytopenia, suggesting an inherent defect to fully reconstitute hematopoiesis. Despite giving rise to multilineage engraftment, IDH1-mutant pHSCs exhibited reduced proliferation, blocked differentiation, downregulation of MHC Class II genes, and reprogramming of oxidative phosphorylation metabolism. Critically, inhibition of oxidative phosphorylation resulted in complete eradication of IDH1-mutant pHSCs but not IDH2-mutant pHSCs or wildtype HSCs. Our results indicate that IDH1-mutant preleukemic clones can be targeted with complex I inhibitors, offering a potential strategy to prevent development and relapse of leukemia.

Simplified Intrafemoral Injections Using Live Mice Allow for Continuous Bone Marrow Analysis

Despite the complexity of hematopoietic cell transplantation in humans, researchers commonly perform intravenous or intrafemoral (IF) injections in mice. In murine models, this technique has been adapted to enhance the seeding efficiency of transplanted hematopoietic stem and progenitor cells (HSPCs). This paper describes a detailed step-by-step technical procedure of IF injection and the following bone marrow (BM) aspiration in mice that allows for serial characterization of cells present in the BM. This method enables the transplantation of valuable samples with low cell numbers that are particularly difficult to engraft by intravenous injection. This procedure facilitates the creation of xenografts that are critical for pathological analysis. While it is easier to access peripheral blood (PB), the cellular composition of PB does not reflect the BM, which is the niche for HSPCs. Therefore, procedures providing access to the BM compartment are essential for studying hematopoiesis. IF injection and serial BM aspiration, as described here, allow for the prospective retrieval and characterization of cells enriched in the BM, such as HSPCs, without sacrificing the mice.

RUNX1 loss renders hematopoietic and leukemic cells dependent on IL-3 and sensitive to JAK inhibition

Disease-initiating mutations in the transcription factor RUNX1 occur as germline and somatic events that cause leukemias with particularly poor prognosis. However, the role of RUNX1 in leukemogenesis is not fully understood, and effective therapies for RUNX1-mutant leukemias remain elusive. Here, we used primary patient samples and a RUNX1-KO model in primary human hematopoietic cells to investigate how RUNX1 loss contributes to leukemic progression and to identify targetable vulnerabilities. Surprisingly, we found that RUNX1 loss decreased proliferative capacity and stem cell function. However, RUNX1-deficient cells selectively upregulated the IL-3 receptor. Exposure to IL-3, but not other JAK/STAT cytokines, rescued RUNX1-KO proliferative and competitive defects. Further, we demonstrated that RUNX1 loss repressed JAK/STAT signaling and rendered RUNX1-deficient cells sensitive to JAK inhibitors. Our study identifies a dependency of RUNX1-mutant leukemias on IL-3/JAK/STAT signaling, which may enable targeting of these aggressive blood cancers with existing agents.

AML/T cell interactomics uncover correlates of patient outcomes and the key role of ICAM1 in T cell killing of AML

T cells are important for the control of acute myeloid leukemia (AML), a common and often deadly malignancy. We observed that some AML patient samples are resistant to killing by human engineered cytotoxic CD4 + T cells. Single-cell RNA-seq of primary AML samples and CD4 + T cells before and after their interaction uncovered transcriptional programs that correlate with AML sensitivity or resistance to CD4 + T cell killing. Resistance-associated AML programs were enriched in AML patients with poor survival, and killing-resistant AML cells did not engage T cells in vitro . Killing-sensitive AML potently activated T cells before being killed, and upregulated ICAM1 , a key component of the immune synapse with T cells. Without ICAM1, killing-sensitive AML became resistant to killing to primary ex vivo -isolated CD8 + T cells in vitro , and engineered CD4 + T cells in vitro and in vivo . Thus, ICAM1 on AML acts as an immune trigger, allowing T cell killing, and could affect AML patient survival in vivo .

SIGNIFICANCE

AML is a common leukemia with sub-optimal outcomes. We show that AML transcriptional programs correlate with susceptibility to T cell killing. Killing resistance-associated AML programs are enriched in patients with poor survival. Killing-sensitive, but not resistant AML activate T cells and upregulate ICAM1 that binds to LFA-1 on T cells, allowing immune synapse formation which is critical for AML elimination.

GRAPHICAL ABSTRACT

Dysregulated Lipid Synthesis by Oncogenic IDH1 Mutation Is a Targetable Synthetic Lethal Vulnerability

Isocitrate dehydrogenase 1 and 2 (IDH) are mutated in multiple cancers and drive production of (R)-2-hydroxyglutarate (2HG). We identified a lipid synthesis enzyme [acetyl CoA carboxylase 1 (ACC1)] as a synthetic lethal target in mutant IDH1 (mIDH1), but not mIDH2, cancers. Here, we analyzed the metabolome of primary acute myeloid leukemia (AML) blasts and identified an mIDH1-specific reduction in fatty acids. mIDH1 also induced a switch to b-oxidation indicating reprogramming of metabolism toward a reliance on fatty acids. Compared with mIDH2, mIDH1 AML displayed depletion of NADPH with defective reductive carboxylation that was not rescued by the mIDH1-specific inhibitor ivosidenib. In xenograft models, a lipid-free diet markedly slowed the growth of mIDH1 AML, but not healthy CD34+ hematopoietic stem/progenitor cells or mIDH2 AML. Genetic and pharmacologic targeting of ACC1 resulted in the growth inhibition of mIDH1 cancers not reversible by ivosidenib. Critically, the pharmacologic targeting of ACC1 improved the sensitivity of mIDH1 AML to venetoclax.

SIGNIFICANCE

Oncogenic mutations in both IDH1 and IDH2 produce 2-hydroxyglutarate and are generally considered equivalent in terms of pathogenesis and targeting. Using comprehensive metabolomic analysis, we demonstrate unexpected metabolic differences in fatty acid metabolism between mutant IDH1 and IDH2 in patient samples with targetable metabolic interventions. See related commentary by Robinson and Levine, p. 266. This article is highlighted in the In This Issue feature, p. 247.

A dehydrated space-weathered skin cloaking the hydrated interior of Ryugu

Without a protective atmosphere, space-exposed surfaces of airless Solar System bodies gradually experience an alteration in composition, structure and optical properties through a collective process called space weathering. The return of samples from near-Earth asteroid (162173) Ryugu by Hayabusa2 provides the first opportunity for laboratory study of space-weathering signatures on the most abundant type of inner solar system body: a C-type asteroid, composed of materials largely unchanged since the formation of the Solar System. Weathered Ryugu grains show areas of surface amorphization and partial melting of phyllosilicates, in which reduction from Fe³⁺ to Fe²⁺ and dehydration developed. Space weathering probably contributed to dehydration by dehydroxylation of Ryugu surface phyllosilicates that had already lost interlayer water molecules and to weakening of the 2.7 µm hydroxyl (-OH) band in reflectance spectra. For C-type asteroids in general, this indicates that a weak 2.7 µm band can signify space-weathering-induced surface dehydration, rather than bulk volatile loss.

Abstract P3105: Improving Cardiovascular Toxicity Of Chronic Myeloid Leukemia Therapy

Introduction: Ponatinib is one of the most cardiotoxic Tyrosine Kinase Inhibitors (TKIs), but continues to be used in clinical practice as it is the only TKI effective against the most common ABL T315I mutation in Chronic Myeloid Leukemia (CML). Long-term exposure to ponatinib increases cardiovascular events including myocardial infarction, heart failure, stroke, peripheral vascular disease and venous thrombosis. Novel therapeutics are needed to provide treatment for this common form of CML while avoiding cardiovascular side effects.

Hypothesis: Chemical reengineering can create novel TKIs effective against T315I mutant CML but with reduced cardiovascular toxicity.

Methods: Using fragment-based approach, we generated new, safer analogues of ponatinib. The anti-tumor efficacy of these analogues was tested in 2 different CML cell lines (K562 T315I and KCL22 T315I) and in CML patient samples. We assayed for myocardial toxicity by measuring contractile function in human iPSC-cardiomyocytes (hiPSC-CMs) using high-throughput functional imaging, and assayed for vascular toxicity by measuring vasculogenesis in human microvascular endothelial cells (HMVECs). Finally, we confirmed the safer cardiovascular profile and adequate anti-tumor efficacy in an in vivo xenograft mouse model of CML.

Results: The new analogues inhibited T315I BCR-ABL kinase activity similar to ponatinib and suppressed T315I mutant CML tumor growth in vitro and in vivo . Compared to ponatinib, the new compounds showed markedly decreased adverse effects on contractility of hiPSC-CMs and vasculogenesis in HMVECs in vitro . The therapeutic window was increased in vivo , leading to regression of human T315I mutant CML xenografts comparable to ponatinib but without increased levels of cardiac troponin. Additionally, we identified multiple kinases, including FGFR1, that were inhibited by ponatinib but not the analogues, suggesting that there is a specific set of kinases responsible for ponatinib toxicity.

Conclusions: This study demonstrates that chemical reengineering can generate novel, cardiovascular-safe TKIs that retain effective therapeutic properties against CML carrying ABL T315I mutation, but that exhibit minimal cardiovascular toxicity compared to ponatinib.

Reengineering Ponatinib to Minimize Cardiovascular Toxicity

Small molecule tyrosine kinase inhibitors (TKI) have revolutionized cancer treatment and greatly improved patient survival. However, life-threatening cardiotoxicity of many TKIs has become a major concern. Ponatinib (ICLUSIG) was developed as an inhibitor of the BCR-ABL oncogene and is among the most cardiotoxic of TKIs. Consequently, use of ponatinib is restricted to the treatment of tumors carrying T315I-mutated BCR-ABL, which occurs in chronic myeloid leukemia (CML) and confers resistance to first- and second-generation inhibitors such as imatinib and nilotinib. Through parallel screening of cardiovascular toxicity and antitumor efficacy assays, we engineered safer analogs of ponatinib that retained potency against T315I BCR-ABL kinase activity and suppressed T315I mutant CML tumor growth. The new compounds were substantially less toxic in human cardiac vasculogenesis and cardiomyocyte contractility assays in vitro. The compounds showed a larger therapeutic window in vivo, leading to regression of human T315I mutant CML xenografts without cardiotoxicity. Comparison of the kinase inhibition profiles of ponatinib and the new compounds suggested that ponatinib cardiotoxicity is mediated by a few kinases, some of which were previously unassociated with cardiovascular disease. Overall, the study develops an approach using complex phenotypic assays to reduce the high risk of cardiovascular toxicity that is prevalent among small molecule oncology therapeutics.

SIGNIFICANCE

Newly developed ponatinib analogs retain antitumor efficacy but elicit significantly decreased cardiotoxicity, representing a therapeutic opportunity for safer CML treatment.

The cell type specific 5hmC landscape and dynamics of healthy human hematopoiesis and TET2-mutant pre-leukemia

The conversion of 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC) is a key step in DNA demethylation that is mediated by ten-eleven-translocation (TET) enzymes, which require ascorbate/vitamin C. Here, we report the 5hmC landscape of normal hematopoiesis and identify cell type-specific 5hmC profiles associated with active transcription and chromatin accessibility of key hematopoietic regulators. We utilized CRISPR/Cas9 to model TET2 loss-of-function mutations in primary human HSPCs. Disrupted cells exhibited increased colonies in serial replating, defective erythroid/megakaryocytic differentiation, and in vivo competitive advantage and myeloid skewing coupled with reduction of 5hmC at erythroid-associated gene loci. Azacitidine and ascorbate restored 5hmC abundance and slowed or reverted the expansion of TET2-mutant clones in vivo. These results demonstrate the key role of 5hmC in normal hematopoiesis and TET2-mutant phenotypes and raise the possibility of utilizing these agents to further our understanding of pre-leukemia/clonal hematopoiesis.

Enasidenib drives human erythroid differentiation independently of isocitrate dehydrogenase 2

Cancer-related anemia is present in more than 60% of newly diagnosed cancer patients and is associated with substantial morbidity and high medical costs. Drugs that enhance erythropoiesis are urgently required to decrease transfusion rates and improve quality of life. Clinical studies have observed an unexpected improvement in hemoglobin and RBC transfusion-independence in patients with acute myeloid leukemia (AML) treated with the isocitrate dehydrogenase 2 (IDH2) mutant-specific inhibitor enasidenib, leading to improved quality of life without a reduction in AML disease burden. Here, we demonstrate that enasidenib enhanced human erythroid differentiation of hematopoietic progenitors. The phenomenon was not observed with other IDH1/2 inhibitors and occurred in IDH2-deficient CRISPR-engineered progenitors independently of D-2-hydroxyglutarate. The effect of enasidenib on hematopoietic progenitors was mediated by protoporphyrin accumulation, driving heme production and erythroid differentiation in committed CD71+ progenitors rather than hematopoietic stem cells. Our results position enasidenib as a promising therapeutic agent for improvement of anemia and provide the basis for a clinical trial using enasidenib to decrease transfusion dependence in a wide array of clinical contexts.

Integrated analysis of patient samples identifies biomarkers for venetoclax efficacy and combination strategies in acute myeloid leukemia

Deregulation of the BCL2 gene family plays an important role in the pathogenesis of acute myeloid leukemia (AML). The BCL2 inhibitor, venetoclax, has received FDA approval for the treatment of AML. However, upfront and acquired drug resistance ensues due, in part, to the clinical and genetic heterogeneity of AML, highlighting the importance of identifying biomarkers to stratify patients onto the most effective therapies. By integrating clinical characteristics, exome and RNA sequencing, and inhibitor data from primary AML patient samples, we determined that myelomonocytic leukemia, upregulation of BCL2A1 and CLEC7A, as well as mutations of PTPN11 and KRAS conferred resistance to venetoclax and multiple venetoclax combinations. Venetoclax in combination with an MCL1 inhibitor AZD5991 induced synthetic lethality and circumvented venetoclax resistance.

Use of polyvinyl alcohol for chimeric antigen receptor T-cell expansion

Serum albumin has long been an essential supplement for ex vivo hematopoietic and immune cell cultures. However, serum albumin medium supplements represent a major source of biological contamination in cell cultures and often cause loss of cellular function. As serum albumin exhibits significant batch-to-batch variability, it has also been blamed for causing major issues in experimental reproducibility. We recently discovered the synthetic polymer polyvinyl alcohol (PVA) as an inexpensive, Good Manufacturing Practice-compatible, and biologically inert serum albumin replacement for ex vivo hematopoietic stem cell cultures. Importantly, PVA is free of the biological contaminants that have plagued serum albumin-based media. Here, we describe that PVA can replace serum albumin in a range of blood and immune cell cultures including cell lines, primary leukemia samples, and human T lymphocytes. PVA can even replace human serum in the generation and expansion of functional chimeric antigen receptor (CAR) T cells, offering a potentially safer and more cost-efficient approach for this clinical cell therapy. In summary, PVA represents a chemically defined, biologically inert, and inexpensive alternative to serum albumin for a range of cell cultures in hematology and immunology.

Large-Scale Clonal Analysis Resolves Aging of the Mouse Hematopoietic Stem Cell Compartment

Aging is linked to functional deterioration and hematological diseases. The hematopoietic system is maintained by hematopoietic stem cells (HSCs), and dysfunction within the HSC compartment is thought to be a key mechanism underlying age-related hematopoietic perturbations. Using single-cell transplantation assays with five blood-lineage analysis, we previously identified myeloid-restricted repopulating progenitors (MyRPs) within the phenotypic HSC compartment in young mice. Here, we determined the age-related functional changes to the HSC compartment using over 400 single-cell transplantation assays. Notably, MyRP frequency increased dramatically with age, while multipotent HSCs expanded modestly within the bone marrow. We also identified a subset of functional cells that were myeloid restricted in primary recipients but displayed multipotent (five blood-lineage) output in secondary recipients. We have termed this cell type latent-HSCs, which appear exclusive to the aged HSC compartment. These results question the traditional dogma of HSC aging and our current approaches to assay and define HSCs.

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Single-cell transplantation reveals dramatic age-related changes in HSC composition

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MyRPs/MySCs increase with age as a frequency of whole BM cells and the HSC compartment

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Latent-HSCs were identified exclusively in the aged bone marrow

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Latent-HSCs have restricted potential in primary, but not secondary, transplants

The surface composition of asteroid 162173 Ryugu from Hayabusa2 near-infrared spectroscopy

The near-Earth asteroid 162173 Ryugu, the target of the Hayabusa2 sample-return mission, is thought to be a primitive carbonaceous object. We report reflectance spectra of Ryugu's surface acquired with the Near-Infrared Spectrometer (NIRS3) on Hayabusa2, to provide direct measurements of the surface composition and geological context for the returned samples. A weak, narrow absorption feature centered at 2.72 micrometers was detected across the entire observed surface, indicating that hydroxyl (OH)-bearing minerals are ubiquitous there. The intensity of the OH feature and low albedo are similar to thermally and/or shock-metamorphosed carbonaceous chondrite meteorites. There are few variations in the OH-band position, which is consistent with Ryugu being a compositionally homogeneous rubble-pile object generated from impact fragments of an undifferentiated aqueously altered parent body.

A Safeguard System for Induced Pluripotent Stem Cell-Derived Rejuvenated T Cell Therapy

The discovery of induced pluripotent stem cells (iPSCs) has created promising new avenues for therapies in regenerative medicine. However, the tumorigenic potential of undifferentiated iPSCs is a major safety concern for clinical translation. To address this issue, we demonstrated the efficacy of suicide gene therapy by introducing inducible caspase-9 (iC9) into iPSCs. Activation of iC9 with a specific chemical inducer of dimerization (CID) initiates a caspase cascade that eliminates iPSCs and tumors originated from iPSCs. We introduced this iC9/CID safeguard system into a previously reported iPSC-derived, rejuvenated cytotoxic T lymphocyte (rejCTL) therapy model and confirmed that we can generate rejCTLs from iPSCs expressing high levels of iC9 without disturbing antigen-specific killing activity. iC9-expressing rejCTLs exert antitumor effects in vivo. The system efficiently and safely induces apoptosis in these rejCTLs. These results unite to suggest that the iC9/CID safeguard system is a promising tool for future iPSC-mediated approaches to clinical therapy.

Effective treatment against severe graft-versus-host disease with allele-specific anti-HLA monoclonal antibody in a humanized mouse model

Graft-versus-host disease (GVHD), mediated by donor-derived alloreactive T cells, is a major cause of nonrelapse mortality in allogeneic hematopoietic stem cell transplantation. Its therapy is not well-defined. We established allele-specific anti-human leukocyte antigen (HLA) monoclonal antibodies (ASHmAbs) that specifically target HLA molecules, with steady death of target-expressing cells. One such ASHmAb, against HLA-A*02:01 (A2-kASHmAb), was examined in a xenogeneic GVHD mouse model. To induce fatal GVHD, non-irradiated NOD/Shi-scid/IL-2Rγ(null) mice were injected with healthy donor human peripheral blood mononuclear cells, some expressing HLA-A*02:01, some not. Administration of A2-kASHmAb promoted the survival of mice injected with HLA-A*02:01-expressing peripheral blood mononuclear cells (p < 0.0001) and, in humanized NOD/Shi-scid/IL-2Rγ(null) mice, immediately cleared HLA-A*02:01-expressing human blood cells from mouse peripheral blood. Human peripheral blood mononuclear cells were again detectable in mouse blood 2 to 4 weeks after A2-kASHmAb administration, suggesting that kASHmAb may be safely administered to GVHD patients without permanently ablating the graft. This approach, different from those in existing GVHD pharmacotherapy, may open a new door for treatment of GVHD in HLA-mismatched allogeneic hematopoietic stem cell transplantation.

Effect of a polymorphism of endothelial nitric oxide synthase gene in Japanese patients with IgA nephropathy

BACKGROUND

Nitric oxide (NO) is synthesized by endothelial cell NO synthase (ecNOS) on vascular endothelium, and it plays a key role in the regulation of blood flow and pressure. A polymorphism of the ecNOS gene was recently shown to be associated with the development of cardiovascular disease.

PATIENTS AND METHODS

We investigated the ecNOS gene polymorphism in 68 Japanese patients with IgA nephropathy (IgAN) and 134 normal controls.

RESULTS

The genotype distributions were not different between the normal controls and the IgAN patients (ecNOS4b/b: ecNOS4b/a: ecNOS4a/a = 106:27:1 and 50:18:0, respectively). There was no significant difference in the renal histopathological grading between the patients with ecNOS4b/a and ecNOS4b/b. However, among the subgroup of patients whose duration of illness was two or more years, the advanced histopathological grading was more frequent in the patients with the ecNOS4b/a genotype (than in those with the ecNOS4b/b (p = 0.04)). The incidence of hypertension was also higher in the patients with the ecNOS4b/a genotype (50% in ecNOS4b/a versus 12% in ecNOS4b/b, p = 0.04).

CONCLUSION

These results suggest that the ecNOS4b/a genotype (or ecNOS4a allele) of the ecNOS gene polymorphism may be involved in the progression of IgAN.

Screening for variants of the uncoupling protein 2 gene in Japanese patients with non-insulin-dependent diabetes mellitus

We examined genetic mutations in the coding regions of the uncoupling protein 2 (UCP2) gene in 100 patients with non-insulin-dependent diabetes mellitus (NIDDM). The sequences of each exon-intron boundary were detected by polymerase chain reaction (PCR) using specific primer pairs designed in the cDNA sequence of UCP2 and a cycle-sequence method. Using the specific primer pairs in the intron 5'- or 3'-untranslated region, each exon with its exon-intron boundaries was amplified with the PCR method, and the PCR products were analyzed using a single-strand conformation polymorphism (SSCP) method. One nucleotide substitution in exon 4 was found, which exchanged Ala (gcc) at position 55 of the amino acid sequence for Val (gtc), previously reported in Denmark by Urhammer et al in 1997. The polymorphism was reanalyzed in all patients and 120 normal subjects using a PCR-restriction fragment length polymorphism method. There was no difference in the genotype distribution between patients and normal subjects, and our genotype distribution was similar to the Danish study. Furthermore, there were no clinical differences between genotype groups among the patients. No other mutation including the exon-intron boundary was found in these patients. Genetic mutations of UCP2 may not be commonly associated with obesity or diabetes in Japanese subjects.

Neuropeptide Y Y1 receptor polymorphism as a prognostic predictor in Japanese patients with IgA nephropathy

BACKGROUND

Neuropeptide Y exhibits a vasoconstricting action and regulates systemic blood pressure as well as noradrenalin. There are 5 types of NPY receptors, Y1 - Y5, which were introduced by pharmacological differences. Recently, a single point mutation in the first intron of the NPY Y1 receptor (NPYY1R) was reported.

SUBJECTS AND METHODS

In this study, we investigated the relationship between NPYY1R gene polymorphism and clinical characteristics in patients with IgA nephropathy using polymerase chain reaction and restriction fragment length polymorphism analysis.

RESULTS

Distribution of the NPYY1R genotypes which were defined as YY, Yy and yy genotypes, did not differ between 60 normal control subjects and 68 patients with IgA nephropathy (15 : 36 : 9 versus 21 : 40 : 7, respectively). In IgA nephropathy patients, the incidence of hypertension and the rate of urinary protein excretion were slightly higher in the non-YY genotype than in the YY genotype group (23% versus 5% and 1.1 +/- 1.2 versus 0.6 +/- 0.4 g/24 h, p = 0.09 and p = 0.05, respectively). The reciprocal of the serum creatinine level was estimated to determine the deterioration in renal function during follow-up after the renal biopsy. The level was lower in the non-YY genotype than in the YY genotype group (-0.002 +/- 0.064 vs 0.033 +/- 0.053/month, respectively, p < 0.01). Multiple regression analysis for the reciprocal of the serum creatinine level revealed that the NPYY1R genotype was an effective variable (p < 0.01).

CONCLUSION

In conclusion, we propose that the NPYY1R gene polymorphism may be a novel prognostic predictor in patients with IgA nephropathy.

A longitudinal analysis of alteration in lecithin-cholesterol acyltransferase and paraoxonase activities following laparoscopic cholecystectomy relative to other parameters of HDL function and the acute phase response

The composition of high-density lipoprotein (HDL) changes during inflammation; however, potential changes of HDL function during inflammation and the effects of acute phase proteins that are either on the HDL particles or in the serum have not been clarified. The concentrations of C-reactive protein (CRP), serum amyloid A protein (apoSAA) isoforms, lipids and apolipoproteins, and the activities of lecithin-cholesterol acyltransferase (LCAT) and paraoxonase (PON) were measured before and after laparoscopic cholecystectomy, in 12 patients with cholecystolithiasis to clarify the function of acute-phase HDL and the relationship between acute-phase proteins and HDL functions. Both acute-phase apoSAA (A-apoSAA) and CRP increased, reached their maximum levels 3-6 days after the operation, and then returned to preoperative levels after 2 weeks. In contrast, apolipoproteins and LCAT decreased reciprocally, reached their minimum levels 3-6 days after the operation, and returned to preoperative levels after 2 weeks. However, PON decreased 3-6 days after the operation, and remained low even after 2 weeks. At the nadir the mean activities of LCAT and PON were 56 and 76% of the preoperative levels, respectively. HDL-cholesterol or constitutive apoSAA did not change significantly. LCAT has been reported to be involved in reverse-cholesterol transport and PON to be preventive for lipid peroxidation of low-density lipoprotein in vitro. Thus, during the acute phase of inflammation, HDL may be altered to an atherogenic state due to a decrease in LCAT and PON activities. Therefore, this longitudinal analysis was carried out to determine whether HDL function is modified in a single episode of inflammation and thus may contribute to the occurrence of atherosclerotic disease in patients with chronic or recurrent acute inflammation.

Serum paraoxonase activity and its relationship to diabetic complications in patients with non-insulin-dependent diabetes mellitus

Paraoxonase (PON) is an esterase associated with high-density lipoprotein (HDL). Serum PON activity is affected by PON gene polymorphism (L/M, Leu-Met54, and Q/R, Gln-Arg191). We investigated PON activity and polymorphism in 108 patients (53 men and 55 women) with non-insulin-dependent diabetes mellitus (NIDDM) and 161 control subjects (82 men and 79 women) matched to the patients by age and gender. Serum PON activity was determined using paraoxon as a substrate. PON gene polymorphisms were detected by the restriction fragment length polymorphism method after a polymerase chain reaction. The mean PON activity in the patients was significantly lower than in the controls (116+/-55 and 162+/-57 U/L, respectively, P < .001). The distribution of each genotype showed no difference between the patient and control groups, and PON activity increased in the order of the QQ < OR < RR genotype and MM < LM < LL genotype in both groups. However, among each genotype subgroup, the activity was lower in patients than in controls. Forty-one patients with retinopathy had lower PON activity than those without the complication (94+/-36 and 129+/-61 U/L, respectively, P < .002). There was also a significant difference in PON activity between patients with and without overt proteinuria (93+/-38 and 122+/-58 U/L, respectively, P < .05). Logistic analysis showed that serum PON activity was one of the significant factors for retinopathy. These results suggest that decreased PON activity in patients with NIDDM is involved in diabetic vascular complications.

Trp64Arg mutation of beta 3-adrenergic receptor and insulin sensitivity in subjects with glucose intolerance

We investigated the relationship between the Trp64Arg mutation in the beta 3-adrenergic receptor gene and insulin sensitivity, which was evaluated by the euglycemic-hyperinsulinemic-clamp technique, in 54 patients with impaired glucose tolerance (IGT) or non-insulin dependent diabetes mellitus (NIDDM) who were not receiving insulin therapy. The frequencies of Trp/Trp, Trp/Arg, and Arg/Arg genotypes in the patients were 63.0, 33.3, and 3.7%, respectively, which did not differ significantly from those of the 227 controls (67.0, 33.3, and 3.7%, respectively, which did not differ significantly from those of the 227 controls (67.0, 31.3, and 1.8%, respectively). The mean glucose infusion rate of the 34 patients with Trp/Trp did not differ from that of the 18 patients with Trp/Arg (4.3 +/- 2.2 and 5.3 +/- 2.4 mg/kg/min, respectively); while that of the 2 patients with Arg/Arg was 11.5 mg/kg/min. There were no differences in the BMI or fat distribution in the abdomen between each genotype of patients, although the frequency of the Arg64 allele tended to increase with body mass index (BMI) in the control subjects under 60 years of age, which suggests that the mutation is involved in weight gain.

Audiological findings of sensorineural deafness associated with a mutation in the mitochondrial DNA

OBJECTIVE

The aim of this study was to investigate audiologic features and the lesion site of sensorineural deafness with mitochondrial DNA mutation at position 3243.

STUDY DESIGN

Case review.

SETTING

The study was conducted at the Kochi Medical School.

PATIENTS

A case of sensorineural deafness in a patient who had a mitochondrial DNA mutation was presented. The incidence of deafness and diabetes mellitus (DM) was very high in the patient's family, but she did not have DM.

MAIN OUTCOME MEASURES

The patient's mitochondrial DNA was examined. Furthermore, the pure-tone audiogram, the Bekesy audiogram, an auditory brain stem response, and the electrocochleogram were analyzed.

RESULTS

The patient's mitochondrial DNA had a point mutation at codon 3243 (A-->G). The pure-tone audiogram showed moderate sensorineural deafness. An auditory brain stem response showed normal latencies. The electrocochleogram showed an enhanced negative summating potential.

CONCLUSIONS

It was speculated that the lesion site of the auditory system was the inner ear. The possible sites in the inner ear were hair cells, the stria vascularis, and the endolymphatic sac.

[Preclinical and clinical studies on the efficacy of bifonazole in patients with tinea pedis at 10 years after approval. Part 1. Susceptibility to bifonazole of clinical isolates of dermatophytes]

An investigation was carried out to determine whether or not here had been any changes in the susceptibility of clinically isolated strains of Trichophyton metagrophytes and Trichophyton rubrum (both leading causes of tinea) to bifonazole, an imidazole derivative and antifungal for topical use. Susceptibility was measured in 107 strains of these fungi isolated from clinical samples during a study on the treatment of tinea pedis with Mycospor cream in 1995, 42 strains isolated and stored in 1990, and 39 strains isolated and stored prior to development of the drug. The results are as follows: (1) There was no distinct difference in the susceptibility to bifonazole of T. mentagrophytes strains isolated before 1986 and those isolated in 1990 or 1995. (2) T. rubrum strains isolated before 1986 were slightly more susceptible to bifonazole than those isolated in 1995, while the 1990 strains were slightly less susceptible than the 1995 strains, but the difference was not significant. (3) The highest MICs of bifonazole for all the T. mentagrophytes and T. rubrum strains isolated from before 1986 and those in 1995 were relatively low, being 2.5 micrograms/ml and 1.25 micrograms/ml, respectively. These results suggest that no resistance or reduced susceptibility to bifonazole has emerged among clinical isolates of dermatophytes since the development of the drug.

[Fundamental and clinical studies on the efficacy of bifonazole in patients with tinea pedis at 10 years after approval. Part 2. Clinical evaluation]

The usefulness of bifonazole (Mycospor), a topical imidazole antifungal agent approved 10 years ago, was evaluated for the treatment of tinea pedis. Mycospor cream was applied by 141 patients with tinea pedis once daily for 4 233ks, and the clinical efficacy and adverse reactions (as well as any correlations with susceptibility of isolates and the mycological activity of the agent against these isolates) were studied. The results were then compared to those of a previous study. The following results were obtained. 1. Mycological activity Mycological examination results became negative in 63.2% (36/57) of the patients with plantar tinea pedis, in 94.1% (32/34) of those with interdigital tinea pedis, and in 74.7% (68/91) of all tinea pedis patients. 2. Mycological activity and MIC No correlation was found between the MICs of bifonazole against the pathogenic fungi and the rate of eradication on mycological examination. 3. Improvement of symptoms The improvement rates for local symptoms were 82.5% for plantar tinea pedis, 85.7% for interdigital tinea pedis, and 83.7% for all tinea pedis. 4. Clinical efficacy Good clinical efficacies were found in 61.4% of the patients with plantar tinea pedis, in 88.6% of those with interdigital tinea pedis, and in 71.7% of all patients. 5. Safety Regarding adverse reactions, what seemed to be contact dermatitis was reported in 5 out of 127 cases (3.9%). The reaction decreased or disappeared in all cases. 6. Usefulness Mycospor was found to be useful in 64.9% of patients with plantar tinea pedis, in 88.6% of those with interdigital tinea pedis, and in 73.9% of all tinea pedis patients. 7. Comparison with former results The results obtained in the present clinical study were comparable to those obtained in patients with tinea pedis treated in a double-blind comparative study conducted during the development of as a new topical antifungal agent. From the above results, Mycospor cream was confirmed to be still useful, although it has been used widely for the topical treatment of cutaneous mycoses in the past 10 years since its approval.

Paraoxonase gene polymorphism in Japanese subjects with coronary heart disease

We investigated the association of paraoxonase (PON) gene polymorphism with both the occurrence of coronary heart disease (CHD) and the severity of coronary artery stenosis in Japanese subjects. PON is a protein associated with plasma HDL. It has been hypothesized an A/B (Gln 192-->Arg) polymorphism of PON may be involved in the pathogenesis of CHD, especially among subjects with non-insulin-dependent diabetes mellitus (NIDDM). The polymorphism was determined in 134 patients with myocardial infarction (MI) or angina pectoris, and in 252 healthy subjects as controls. The frequencies of the AA, AB, and BB genotypes in the patients were 15, 50 and 35%, respectively, and these frequencies did not differ from those in control subjects (14, 49, and 37%). The relative risk of CHD was not found to be associated with these genotypes. These data also were similar among selected subgroups (patients with MIs, those with a low-risk lipoprotein profile for CHD, and those with NIDDM). Neither the number of affected vessels nor Gensini's scores differed among the genotype groups. Our case-control study in Japanese subjects did not show that the PON A/B polymorphism is associated with a risk of CHD.

Simple obesity with cardiomyopathy of obesity

A 32-year-old obese female was hospitalized with dyspnea. Echocardiogram revealed left ventricular dilatation. Chest X-ray film showed enlarged heart size and prominent pulmonary congestion. Simple obesity with congestive heart failure (CHF) due to cardiomyopathy of obesity was diagnosed according to the absence of obvious disease that caused obesity or CHF. After diet therapy and medication, subjective symptoms disappeared and body weight was reduced from 137 kg to 85 kg. Although few reports of cardiomyopathy of obesity have been reported in Japan, we propose the possibility that similar cases will be on the increase because Japanese dietary habits are now becoming more similar to those of Caucasians.

Significance of angiotensin I-converting enzyme and angiotensin II type 1 receptor gene polymorphisms as risk factors for coronary heart disease

The D allele of an insertion/deletion (I/D) polymorphism in the angiotensin I-converting enzyme (ACE) gene is associated with a risk of myocardial infarction, and the relative risk associated with the ACE D allele is increased by the C allele of an angiotensin II type 1 receptor (AT1R) gene polymorphism (an A-->C transversion at nucleotide position 1166) [28]. The relation of the ACE and AT1R gene polymorphisms to coronary heart disease and the severity of coronary artery stenosis has now been investigated in 133 patients with myocardial infarction (MI) or angina pectoris who underwent coronary angiography and in 258 control subjects. The frequency of the ACE DD genotype as compared with non-DD was significantly higher in the patients who experienced an MI and in the low-risk patients than that in the controls (P < 0.05). The DD genotype showed a significantly increased risk of MI (odds ratio 1.85). The frequency of the AT1R A/C genotypes did not differ between the patients and the controls. The severity of coronary stenosis in the patients was estimated by the number of affected vessels (> 75% stenosis) and the coronary score of Gensini. Neither the number of affected vessels nor the coronary score differed among the ACE I/D genotypes. However, the number of affected vessels was significantly greater in patients with the AT1R AC genotype than in those with the 4A genotype (1.93 +/- 0.27 vs. 1.27 +/- 0.99; P < 0.05) (CC genotype was not found in the patients). After excluding patients with diabetes mellitus, the coronary score of those with the AC genotype was also significantly higher than in those with the AA genotype (51.7 +/- 34.4 vs. 18.2 +/- 23.3; P < 0.01). These results suggest that the ACE D allele is associated with the occurrence of myocardial infarction, while the AT1R C allele is involved in the development of the coronary artery stenosis.

Systemic lupus erythematosus relapse with lupus cystitis

A 45-year-old woman who had been diagnosed as having systemic lupus erythematosus (SLE) at the age of 28 years and who had been in remission developed severe urinary frequency, watery diarrhea, vomiting and weight loss. She also developed acute renal failure and her serological examination was consistent with active SLE. She had a markedly decreased urinary bladder capacity of 20 ml with hydroureteronephrosis. Histopathological study of her urinary bladder biopsy specimen showed mucosal edema, infiltration by lymphocytes and granulocytes, and deposition of IgA in the epithelium and submucosal region. We diagnosed this as a case of lupus cystitis. The patient's symptoms were alleviated by bilateral nephrostomy and corticosteroid therapy. In the present episode the patient showed none of the usual symptoms of SLE. This case and others reported in the literature show that lupus cystitis presents with specific signs and symptoms and therefore, this syndrome may represent a specific clinical manifestation of SLE.

Scalp hair loss caused by octreotide in a patient with acromegaly: a case report

We used octreotide to treat a woman with acromegaly and observed pituitary adenoma shrinkage after 5 months. Diffuse scalp hair loss occurred after 5 months, resulting in the discontinuation of treatment. After the cessation of octreotide, the hair loss stopped and hair growth resumed. Since bromocriptine did not effectively decrease the GH level of the patient, we decided to perform transsphenoidal surgery. After resection of the pituitary adenoma, her GH and IGF-1 levels were normalized. Although octreotide-induced scalp hair loss has not been well recognized, we should pay more attention to this side effect.

Hypothyroidism preceding hyperthyroidism in a patient with continuously positive thyroid stimulating antibody

A 62-year-old woman was initially hypothyroid and then developed hyperthyroidism with continuously positive thyroid-stimulating antibody (TSAb). When she visited our hospital with the complaint of the feel of skipping beats, her serum free T4 level was initially low and thyrotropin (TSH) level was slightly elevated. One month after starting the supplement therapy with l-T4, she developed hyperthyroidism with increased 123I-thyroid uptake. TSH-binding inhibitor immunoglobulin (TBII) was slightly elevated only during the hypothyroid stage. Throughout the whole course, TSAb was continuously positive, while thyroid stimulation-blocking antibody (TSBAb) was not detectable. Primary hypothyroidism with TSAb may suggest the possibility of subsequent development of hyperthyroidism.

Relationship of low-density lipoprotein particle size to plasma lipoproteins, obesity, and insulin resistance in Japanese men

OBJECTIVE

To determine the clinical characteristics of patients with small low-density lipoprotein (LDL) particles among Japanese men with mild glucose intolerance and to investigate the relationship of LDL particle size to the levels of other plasma lipoproteins, obesity, insulin resistance, and blood pressure (BP).

RESEARCH DESIGN AND METHODS

The subjects were 40 men with impaired glucose tolerance or diabetes treated by diet alone, and 40 healthy men matched for age and body mass index (BMI) were used as control subjects. LDL particle size was measured using gradient gel electrophoresis.

RESULTS

Of the 40 patients with glucose intolerance, 19 had small LDL (particle size < 25.5 nm) compared with only 4 of the 40 control subjects. In the patients with small LDL, the plasma levels of cholesterol, triglycerides, and apolipoprotein B, the fasting serum immunoreactive insulin, and the waist-to-hip ratio were all higher than in the patients with normal LDL (particle size > or = 25.5 nm), while the high-density lipoprotein cholesterol level was lower. However, there were no significant differences in BMI, BP, or insulin sensitivity in a euglycemic clamp study between the small-LDL and normal-LDL subgroups.

CONCLUSIONS

Japanese men with glucose intolerance frequently have small LDL, and this abnormality is associated with other dyslipoproteinemias and increased waist-to-hip ratio.

Henoch-Schönlein purpura with rapidly progressive glomerulonephritis and fatal intraperitoneal hemorrhage in an adult

We report here the autopsy findings in a 51-year-old man who had been admitted with Henoch-Schönlein purpura (HSP) accompanied by rapidly progressive glomerulonephritis and massive intraperitoneal hemorrhage, leading to death. While the intraperitoneal hemorrhage was the primary cause of death, the patient may have suffered widespread intraperitoneal vasculitis due to HSP, or hemorrhagic pancreatitis due to the concurrent administration of a steroid and furosemide. We emphasize the acute hemorrhagic pancreatitis is a possible complication in patients with generalized vasculitis, including HSP and collagen disease, during the concurrent administration of steroids and other agents.

Localized polyarteritis nodosa in the forearm and epididymis

We report localized polyarteritis nodosa in a 31-year-old man who had painful nodules in the left forearm and scrotum. Histopathological findings of both tissues revealed distinct arteritis. However, he had no clinical evidence of any systemic disease. We finally diagnosed this case as a localized polyarteritis nodosa occurring in both the left forearm and epididymis. This form of polyarteritis nodosa has not been reported in the literature.

Characterization of beta-connectin (titin 2) from striated muscle by dynamic light scattering

Connectin (titin) is a large filamentous protein (single peptide) with a molecular mass of approximately 3 MDa, contour length approximately 900 nm, and diameter approximately 4 nm, and resides in striated muscle. Connectin links the thick filaments to the Z-lines in a sarcomere and produces a passive elastic force when muscle fiber is stretched. The aim of this study is to elucidate some aspects of physical properties of isolated beta-connectin (titin 2), a proteolytic fragment of connectin, by means of dynamic light-scattering (DLS) spectroscopy. The analysis of DLS spectra for beta-connectin gave the translational diffusion coefficient of 3.60 x 10(-8) cm2/s at 10 degrees C (or the hydrodynamic radius of 44.1 nm), molecular mass little smaller than 3.0 MDa (for a literature value of sedimentation coefficient), the root-mean-square end-to-end distance of 163 nm (or the radius of gyration of 66.6 nm), and the Kuhn segment number of 30 and segment length of 30 nm (or the persistence length of 15 nm). These results permitted to estimate the flexural rigidity of 6.0 x 10(-20) dyn x cm2 for filament bending, and the elastic constant of 7 dyn/cm for extension of one persistence length. Based on a simple model, implications of the present results in muscle physiology are discussed.

A novel domain sequence of connectin localized at the I band of skeletal muscle sarcomeres: homology to neurofilament subunits

A cDNA of 4.0 kb was cloned from a chicken embryo skeletal muscle cDNA library, using an antibody to muscle elastic protein connectin (titin), the molecular mass of which is estimated to be 3,000 kDa. Immunoelectron microscopy revealed that the antiserum raised against the product of the cDNA expressed in E. coli bound to the epitopes of the connectin filament near the N2 line of chicken breast muscle sarcomeres. The predicted amino acid sequence contains eight immunoglobulin C2 motifs and regions highly homologous with the high and medium molecular weight subunits of neurofilament. In addition, there are regions homologous with desmoplakin, calsequestrin, and calpastatin.