Gut microbiome and metabolome profiling in Framingham heart study reveals cholesterol-metabolizing bacteria

Accumulating evidence suggests that cardiovascular disease (CVD) is associated with an altered gut microbiome. Our understanding of the underlying mechanisms has been hindered by lack of matched multi-omic data with diagnostic biomarkers. To comprehensively profile gut microbiome contributions to CVD, we generated stool metagenomics and metabolomics from 1,429 Framingham Heart Study participants. We identified blood lipids and cardiovascular health measurements associated with microbiome and metabolome composition. Integrated analysis revealed microbial pathways implicated in CVD, including flavonoid, γ-butyrobetaine, and cholesterol metabolism. Species from the Oscillibacter genus were associated with decreased fecal and plasma cholesterol levels. Using functional prediction and in vitro characterization of multiple representative human gut Oscillibacter isolates, we uncovered conserved cholesterol-metabolizing capabilities, including glycosylation and dehydrogenation. These findings suggest that cholesterol metabolism is a broad property of phylogenetically diverse Oscillibacter spp., with potential benefits for lipid homeostasis and cardiovascular health.

Linking microbial genes to plasma and stool metabolites uncovers host-microbial interactions underlying ulcerative colitis disease course

Understanding the role of the microbiome in inflammatory diseases requires the identification of microbial effector molecules. We established an approach to link disease-associated microbes to microbial metabolites by integrating paired metagenomics, stool and plasma metabolomics, and culturomics. We identified host-microbial interactions correlated with disease activity, inflammation, and the clinical course of ulcerative colitis (UC) in the Predicting Response to Standardized Colitis Therapy (PROTECT) pediatric inception cohort. In severe disease, metabolite changes included increased dipeptides and tauro-conjugated bile acids (BAs) and decreased amino-acid-conjugated BAs in stool, whereas in plasma polyamines (N-acetylputrescine and N1-acetylspermidine) increased. Using patient samples and Veillonella parvula as a model, we uncovered nitrate- and lactate-dependent metabolic pathways, experimentally linking V. parvula expansion to immunomodulatory tryptophan metabolite production. Additionally, V. parvula metabolizes immunosuppressive thiopurine drugs through xdhA xanthine dehydrogenase, potentially impairing the therapeutic response. Our findings demonstrate that the microbiome contributes to disease-associated metabolite changes, underscoring the importance of these interactions in disease pathology and treatment.

Computational prediction and experimental validation of Salmonella Typhimurium SopE-mediated fine-tuning of autophagy in intestinal epithelial cells

Macroautophagy is a ubiquitous homeostasis and health-promoting recycling process of eukaryotic cells, targeting misfolded proteins, damaged organelles and intracellular infectious agents. Some intracellular pathogens such as Salmonella enterica serovar Typhimurium hijack this process during pathogenesis. Here we investigate potential protein-protein interactions between host transcription factors and secreted effector proteins of Salmonella and their effect on host gene transcription. A systems-level analysis identified Salmonella effector proteins that had the potential to affect core autophagy gene regulation. The effect of a SPI-1 effector protein, SopE, that was predicted to interact with regulatory proteins of the autophagy process, was investigated to validate our approach. We then confirmed experimentally that SopE can directly bind to SP1, a host transcription factor, which modulates the expression of the autophagy gene MAP1LC3B. We also revealed that SopE might have a double role in the modulation of autophagy: Following initial increase of MAP1LC3B transcription triggered by Salmonella infection, subsequent decrease in MAP1LC3B transcription at 6h post-infection was SopE-dependent. SopE also played a role in modulation of the autophagy flux machinery, in particular MAP1LC3B and p62 autophagy proteins, depending on the level of autophagy already taking place. Upon typical infection of epithelial cells, the autophagic flux is increased. However, when autophagy was chemically induced prior to infection, SopE dampened the autophagic flux. The same was also observed when most of the intracellular Salmonella cells were not associated with the SCV (strain lacking sifA) regardless of the autophagy induction status before infection. We demonstrated how regulatory network analysis can be used to better characterise the impact of pathogenic effector proteins, in this case, Salmonella. This study complements previous work in which we had demonstrated that specific pathogen effectors can affect the autophagy process through direct interaction with autophagy proteins. Here we show that effector proteins can also influence the upstream regulation of the process. Such interdisciplinary studies can increase our understanding of the infection process and point out targets important in intestinal epithelial cell defense.

Autoantibodies are present in the bronchoalveolar lavage but not circulation in patients with fibrotic interstitial lung disease

Background

Fibrotic interstitial lung disease (fILD) has previously been associated with the presence of autoantibody. While studies have focused on systemic autoimmunity, the role of local autoantibodies in the airways remains unknown. We therefore extensively characterised the airway and peripheral autoantibody profiles in patients with fILD, and assessed association with disease severity and outcome.

Methods

Bronchoalveolar lavage (BAL) fluid was collected from a cohort of fILD patients and total BAL antibody concentrations were quantified. An autoantigen microarray was used to measure IgG and IgA autoantibodies against 122 autoantigens in BAL from 40 idiopathic pulmonary fibrosis (IPF), 20 chronic hypersensitivity pneumonitis (CHP), 20 connective tissue disease-associated ILD (CTD-ILD) patients and 20 controls.

Results

A subset of patients with fILD but not healthy controls had a local autoimmune signature in their BAL that was not present systemically, regardless of disease. The proportion of patients with IPF with a local autoantibody signature was comparable to that of CTD-ILD, which has a known autoimmune pathology, identifying a potentially novel subset of patients. The presence of an airway autoimmune signature was not associated with reduced survival probability or changes in lung function in the cohort as a whole. Patients with IPF had increased BAL total IgA and IgG₁ while subjects with CHP had increased BAL IgA, IgG₁ and IgG₄. In patients with CHP, increased BAL total IgA was associated with reduced survival probability.

Conclusion

Airway autoantibodies that are not present systemically identify a group of patients with fILD and the mechanisms by which these autoantibodies contribute to disease requires further investigation.

Autoantibodies are present in the bronchoalveolar lavage but not circulation in patients with fibrotic interstitial lung diseasehttps://bit.ly/3CNvKjj

Enhanced IL-1β Release Following NLRP3 and AIM2 Inflammasome Stimulation Is Linked to mtROS in Airway Macrophages in Pulmonary Fibrosis

Fibrotic Interstitial lung diseases (ILDs) are complex disorders of variable clinical behaviour. The majority of them cause significant morbidity, whilst Idiopathic Pulmonary Fibrosis (IPF) is recognised as the most relentless. NLRP3, AIM2, and NLRC4 inflammasomes are multiprotein complexes driving IL-1β release; a proinflammatory and profibrotic cytokine. Several pathogenetic factors associated with IPF are identified as inflammasome activators, including increases in mtROS and bacterial burden. Mitochondrial oxidation and alterations in bacterial burden in IPF and other ILDs may lead to augmented inflammasome activity in airway macrophages (AMs). IPF (n=14), non-IPF-ILDs (n=12) patients and healthy subjects (n=12) were prospectively recruited and AMs were isolated from bronchoalveolar lavage. IL-1β release resulting from NLRP3, AIM2 and NLRC4 inflammasomes stimulation in AMs were determined and baseline levels of mitochondrial ROS and microbial burden were also measured. Our results showed that NLRP3 was more inducible in IPF and other ILDs compared to controls. Additionally, following AIM2 activation IL-1β release was significantly higher in IPF compared to controls, whereas similar trends were observed in Non-IPF-ILDs. NLRC4 activation was similar across groups. mtROS was significantly associated with heightened NLRP3 and AIM2 activation, and mitochondrial antioxidant treatment limited inflammasome activation. Importantly, microbial burden was linked to baseline IL-1β release and AIM2 and IL-18 relative expression independently of mtROS. In conclusion, the above findings suggested a link between the overactivation of NLRP3 and AIM2 inflammasomes, driven by mitochondrial oxidation, in the pathogenesis of lung fibrosis while changes in the microbiota may prime the inflammasome in the lungs.

The Respiratory Microbiome in Chronic Hypersensitivity Pneumonitis Is Distinct from That of Idiopathic Pulmonary Fibrosis

Rationale: Chronic hypersensitivity pneumonitis (CHP) is a condition that arises after repeated exposure and sensitization to inhaled antigens. The lung microbiome is increasingly implicated in respiratory disease, but, to date, no study has investigated the composition of microbial communities in the lower airways in CHP.

Objectives: To characterize and compare the airway microbiome in subjects with CHP, subjects with idiopathic pulmonary fibrosis (IPF), and control subjects.

Methods: We prospectively recruited individuals with a CHP diagnosis (n = 110), individuals with an IPF diagnosis (n = 45), and control subjects (n = 28). Subjects underwent BAL and bacterial DNA was isolated, quantified by quantitative PCR and the 16S ribosomal RNA gene was sequenced to characterize the bacterial communities in the lower airways.

Measurements and Main Results: Distinct differences in the microbial profiles were evident in the lower airways of subjects with CHP and IPF. At the phylum level, the prevailing microbiota of both subjects with IPF and subjects with CHP included Firmicutes, Bacteroidetes, Proteobacteria, and Actinobacteria. However, in IPF, Firmicutes dominated, whereas the percentage of reads assigned to Proteobacteria in the same group was significantly lower than the percentage found in subjects with CHP. At the genus level, the Staphylococcus burden was increased in CHP, and Actinomyces and Veillonella burdens were increased in IPF. The lower airway bacterial burden in subjects with CHP was higher than that in control subjects but lower than that of those with IPF. In contrast to IPF, there was no association between bacterial burden and survival in CHP.

Conclusions: The microbial profile of the lower airways in subjects with CHP is distinct from that of IPF, and, notably, the bacterial burden in individuals with CHP fails to predict survival.

Respiratory microbiome and epithelial interactions shape immunity in the lungs

The airway epithelium represents a physical barrier to the external environment acting as the first line of defence against potentially harmful environmental stimuli including microbes and allergens. However, lung epithelial cells are increasingly recognized as active effectors of microbial defence, contributing to both innate and adaptive immune function in the lower respiratory tract. These cells express an ample repertoire of pattern recognition receptors with specificity for conserved microbial and host motifs. Modern molecular techniques have uncovered the complexity of the lower respiratory tract microbiome. The interaction between the microbiota and the airway epithelium is key to understanding how stable immune homeostasis is maintained. Loss of epithelial integrity following exposure to infection can result in the onset of inflammation in susceptible individuals and may culminate in lung disease. Here we discuss the current knowledge regarding the molecular and cellular mechanisms by which the pulmonary epithelium interacts with the lung microbiome in shaping immunity in the lung. Specifically, we focus on the interactions between the lung microbiome and the cells of the conducting airways in modulating immune cell regulation, and how defects in barrier structure and function may culminate in lung disease. Understanding these interactions is fundamental in the search for more effective therapies for respiratory diseases.

Bacterial burden in the lower airways predicts disease progression in idiopathic pulmonary fibrosis and is independent of radiological disease extent

Increasing bacterial burden in the lower airways of patients with idiopathic pulmonary fibrosis confers an increased risk of disease progression and mortality. However, it remains unclear whether this increased bacterial burden directly influences progression of fibrosis or simply reflects the magnitude of the underlying disease extent or severity.We prospectively recruited 193 patients who underwent bronchoscopy and received a multidisciplinary diagnosis of idiopathic pulmonary fibrosis. Quantification of the total bacterial burden in bronchoalveolar lavage fluid was performed by 16S rRNA gene qPCR. Imaging was independently evaluated by two readers assigning quantitative scores for extent, severity and topography of radiographic changes and relationship of these features with bacterial burden was assessed.Increased bacterial burden significantly associated with disease progression (HR 2.1; 95% CI 1.287-3.474; p=0.0028). Multivariate stepwise regression demonstrated no relationship between bacterial burden and radiological features or extent of disease. When specifically considering patients with definite or probable usual interstitial pneumonia there was no difference in bacterial burden between these two groups. Despite a postulated association between pleuroparenchymal fibroelastosis and clinical infection, there was no relationship between either the presence or extent of pleuroparenchymal fibroelastosis and bacterial burden.We demonstrate that bacterial burden in the lower airways is not simply secondary to the extent of the underlying architectural destruction of the lung parenchyma seen in idiopathic pulmonary fibrosis. The independent nature of this association supports a relationship with the underlying pathogenic mechanisms and highlights the urgent need for functional studies.

The contribution of infection and the respiratory microbiome in acute exacerbations of idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) arises in genetically susceptible individuals as a result of an aberrant wound-healing response following repetitive alveolar injury. The clinical course of the disease remains both variable and unpredictable with periods of more rapid decline, termed acute exacerbation of IPF (AE-IPF), often punctuating the disease trajectory. Exacerbations carry a significant morbidity and mortality, and their exact pathogenesis remains unclear. Given the emerging evidence that disruption and alteration in the lung microbiome plays a role in the pathogenesis and progression of IPF, this review discusses the current knowledge of the contribution of infection and the respiratory microbiome to AE-IPF.

[Firearms related suicide/homicide rate among the security guards population in Italy]

OBJECTIVE

The main aim of this study is evaluating the suicide/homicide rate of the Italian security guards population compared to other armed and general populations during a recent period.

METHODS

The authors reviewed the incidence of suicides and homicides among security guards from 1996 to 2006 and, where information was available, a comparison was made with Italian population adapted by age. Comparisons with the general population were also made.

RESULTS

The average rate of firearms related suicide among the security guards population during the established period was 11.7 per 100,000 persons-years (95% CI = 6.6-16.7) compared to a guns-related suicide rate of 0.7 per 100,000 person-years, (95% CI = 0.6-0.7) and a non-guns related rate of 5.5 per 100,000 persons-years, (95% CI = 5.2-5.9) for the general population adjusted for age. The overall homicide rate among security guards during the period was 11.4 per 100,000 person-years (95% CI = 6.2-15.4) compared with the homicide rate for the Italian population of 5.4 per 100,000 persons-years, (95% CI = 7.3-15.4).

CONCLUSION

The rate of suicide and homicide among the Italian security guards population was higher than the suicide/homicide rate in the general population. These results show that the phenomenon we have described needs attention and specific prevention activities.

Fungal infections in recipients of hematopoietic stem cell transplants: results of the SEIFEM B-2004 study--Sorveglianza Epidemiologica Infezioni Fungine Nelle Emopatie Maligne

BACKGROUND

The purpose of our study was to evaluate the incidence and outcome of invasive fungal infection (IFI) among patients who underwent autologous or allogeneic hematopoietic stem cell transplantation (HSCT) at 11 Italian transplantation centers.

METHODS

This cohort-retrospective study, conducted during 1999-2003, involved HSCT patients admitted to 11 tertiary care centers or university hospitals in Italy, who developed IFIs (proven or probable).

RESULTS

Among 3228 patients who underwent HSCT (1249 allogeneic HSCT recipients and 1979 autologous HSCT recipients), IFI occurred in 121 patients (overall incidence, 3.7%). Ninety-one episodes (2.8% of all patients) were due to molds, and 30 (0.9%) were due to yeasts. Ninety-eight episodes (7.8%) occurred among the 1249 allogeneic HSCT recipients, and 23 (1.2%) occurred among the 1979 autologous HSCT recipients. The most frequent etiological agents were Aspergillus species (86 episodes) and Candida species (30 episodes). The overall mortality rate was 5.7% among allogeneic HSCT recipients and 0.4% among autologous HSCT recipients, whereas the attributable mortality rate registered in our population was 65.3% (72.4% for allogeneic HSCT recipients and 34.7% for autologous HSCT recipients). Etiology influenced the patients' outcomes: the attributable mortality rate for aspergillosis was 72.1% (77.2% and 14.3% for allogeneic and autologous HSCT recipients, respectively), and the rate for Candida IFI was 50% (57.1% and 43.8% for allogeneic and autologous HSCT recipients, respectively).

CONCLUSIONS

IFI represents a common complication for allogeneic HSCT recipients. Aspergillus species is the most frequently detected agent in these patients, and aspergillosis is characterized by a high mortality rate. Conversely, autologous HSCT recipients rarely develop aspergillosis, and the attributable mortality rate is markedly lower. Candidemia was observed less often than aspergillosis among both allogeneic and autologous HSCT recipients; furthermore, there was no difference in either the incidence of or the attributable mortality rate for candidemia among recipients of the 2 transplant types.

Biological effects of pegfilgrastim after myelosuppressive chemotherapy in breast cancer

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Background: The dose and schedule of chemotherapy (CT), that play a crucial role in the outcome of pts with chemosensitive tumors, were made feasible with the primary use of colony stimulating factors. Few data are available on the in vivo biological effects of the “long-lasting” cytokine pegfilgrastim. We have focused on the cytokinetic effects on the CD34+/38+ peripheral blood (PB) progenitor cell subset and on its influence on neutrophils functional parameters. Methods: We studied PB samples from 14 breast cancer pts (median age 47 yrs; 35–61 yrs), treated with Docetaxel (80 mg/sqm, d 1) + Epirubicin (75 mg/sqm, d 1) + pegfilgrastim (6 mg s.c. on d +1). The % of CD34+/38+ circulating progenitor cells (CPCs) (sorted with immunomagnetic procedure) undergoing G0/G1, S and G2/M phases of the cell cycle or showing apoptotic features were evaluated using flow cytometry. Annexin V was quantitated at a single cell level and correlated with cell cycle phases. On PB buffy coat smears, alkaline phosphatase activity by cytochemistry, actin polymerization using FITC-labelled phalloidin and apoptosis by TUNEL technique, were evaluated on neutrophils. Results: Seven days following CT + pegfilgrastim the CD34+/38+ absolute numbers were: 46 (27–74) and 41 (25–66) on day 14+ from CT.On day 7+ the % of CD34+/38+ CPCs in S-phase was 13.0 ± 9 while 3.7% ± 6 of this cell subset showed apoptotic features. One week later, these values were 8.4% ± 7 and 7.7% ± 5, respectively. We also observed: stability of the absolute neutrophil count for all the duration of treatment; a significant increase of the leucocyte alkaline phosphatase; abnormalities of actin assembly in neutrophils, indicative of changes in cytoskeleton organization, and a significant reduction of neutrophil apoptosis. Conclusions: 1) pegfilgrastim exerts stimulatory effects on cell cycle status of PB CD34+/38+ CPCs, protecting them from apoptosis; this is evident 7 days after its administration and tends to decrease one week later 2) pegfilgrastim improves the neutrophil function by inhibiting their accelerated apoptosis and prolonging survival. These data could be useful when dose-dense CT is planned with pegfilgrastim support.

No significant financial relationships to disclose.

Flow cytometry evaluation of erythroid dysplasia in patients with myelodysplastic syndrome

Erythroid dysplasia is the pathologic hallmark of myelodysplastic syndromes (MDS). To develop a quantitative flow-cytometry approach to its evaluation, we analyzed the expression of CD71, CD105, cytosolic H-ferritin (HF), cytosolic L-ferritin (LF) and mitochondrial ferritin (MtF) in erythroblasts from 104 MDS patients, 69 pathologic control patients and 19 healthy subjects. Six-parameter, 4-color flow cytometry was employed, and data were expressed as mean fluorescence intensity. Compared with pathologic and healthy controls, MDS patients had higher expression of HF (P < 0.001) and CD105 (P < 0.001), and lower expression of CD71 (P < 0.001). MtF was specifically detected in MDS with ringed sideroblasts, and there was a close relationship between its expression and Prussian blue staining (r = 0.89, P < 0.001). In vitro cultures of myelodysplastic hematopoietic progenitors showed that both HF and MtF were expressed at a very early stage of erythroid differentiation, and that MtF expression is specifically related to mitochondrial iron loading. A classification function based on expression levels of HF, CD71 and CD105 allowed us to correctly classify > 95% of MDS patients. This flow-cytometry approach provides an accurate quantitative evaluation of erythroid dysplasia and allows a reliable diagnosis of sideroblastic anemia, and may therefore be a useful tool in the work-up of patients with MDS.

Flow cytometry evaluation of erythroid and myeloid dysplasia in patients with myelodysplastic syndrome

The purpose of this study was to develop a flow cytometric approach to the evaluation of marrow dysplasia in myelodysplastic syndromes (MDS). We first studied a cohort of 103 MDS patients as well as 46 pathological and healthy controls. Flow cytometry data were expressed as percentage of positive cells. Analysis of erythroid cells showed higher proportions of immature cells (P < 0.001) and decreased levels of CD71 expression on nucleated red cells (P = 0.02) in MDS. Analysis of myeloid cells showed lower proportions of CD10+ and higher proportions of CD56+ granulocytes (P < 0.001), and increased ratios of immature to mature cells (P = 0.007). Since no single immunophenotype could accurately differentiate MDS from other conditions, we used discriminant analysis for generating erythroid and myeloid classification functions using combinations of immunophenotypic parameters. These functions were prospectively validated in a testing cohort of 69 MDS patients and 46 pathological controls. A diagnosis of MDS was obtained in 60/69 cases (87%). No false-positive results were noticed among controls. Significant correlations between values of these functions and both degree of morphological dysplasia and the International Prognostic Scoring System were found. These findings indicate that flow cytometry evaluation of marrow dysplasia is feasible and may be useful in the work-up of individual MDS patients.

Retrospective comparison of qualitative and quantitative reverse transcriptase polymerase chain reaction in diagnosing and monitoring the ALL1-AF4 fusion transcript in patients with acute lymphoblastic leukaemia

We compared quantitative reverse transcriptase polymerase chain reaction (Q-RT-PCR) to qualitative RT-PCR in determining response to therapy and predicting clinical outcome in 18 retrospectively selected patients with ALL positive for the ALL1-AF4 fusion and with frozen RNA samples collected at diagnosis and during follow-up (96 samples analysed). The ALL1-AF4 junction was detected by qualitative RT-PCR in 18 patients and by Q-RT-PCR in 17 patients (one patient harboured the rare e10-e6 ALL1-AF4 junction, which falls outside of the primer and probe location designed for the Q-RT-PCR). In three of the 12 patients negative to qualitative RT-PCR after induction therapy, a small number of ALL1-AF4 copies was detected by Q-RT-PCR. Thus nine patients were negative and eight positive. Seven of the eight positive patients suffered a relapse, including two of the three patients positive to Q-RT-PCR yet negative to qualitative RT-PCR. Moreover, we found two (5%) discordant results among the 39 follow-up tests of the nine patients who converted to a negative qualitative-quantitative PCR status. The results suggest that qualitative RT-PCR is more appropriate for the routine diagnosis of this genetic alteration. However, Q-RT-PCR is more accurate in assessing the molecular response after induction treatment and could be more useful in clinical decision-making in ALL1-AF4-positive ALL patients.

Impaired bone marrow hematopoietic progenitor cell function in rheumatoid arthritis patients candidated to autologous hematopoietic stem cell transplantation

We have evaluated bone marrow morphology, percentage of bone marrow CD34(+) cells, proliferative activity of bone marrow precursors, clonogenic assay (BFU-E and CFU-GM) in short-term bone marrow cultures, and bone marrow cell apoptosis, together with serum TNF-alpha and IL-6, in 16 chronic, refractory RA patients, as well as in five healthy controls. Of 16 RA patients (68.7%), 11 showed a reduced bone marrow cellularity, while it was normal in all the controls. In RA patients, the median percentage of CD34(+) bone marrow cells, the median percentage of proliferating bone marrow myeloid precursors, and the median number of both BFU-E and CFU-GM colonies were significantly lower than observed in the controls. As far as TNF-alpha and IL-6 titers is concerned, the latter did not significantly differ from controls' values, while TNF-alpha titers were significantly lower in healthy controls. Finally, the median apoptotic index of early bone marrow myeloid cells of RA patients was significantly higher compared with controls. These observations may identify the biological risk factors for impaired mobilization and/or engraftment when RA patients are candidates for autologous hematopoietic stem cell grafting.

A human mitochondrial ferritin encoded by an intronless gene

Ferritin is a ubiquitous protein that plays a critical role in regulating intracellular iron homoeostasis by storing iron inside its multimeric shell. It also plays an important role in detoxifying potentially harmful free ferrous iron to the less soluble ferric iron by virtue of the ferroxidase activity of the H subunit. Although excess iron is stored primarily in cytoplasm, most of the metabolically active iron in cells is processed in mitochondria. Little is yet known of how these organelles regulate iron homeostasis and toxicity. Here we report an unusual intronless gene on chromosome 5q23.1 that encodes a 242-amino acid precursor of a ferritin H-like protein. This 30-kDa protein is targeted to mitochondria and processed to a 22-kDa subunit that assembles into typical ferritin shells and has ferroxidase activity. Immunohistochemical analysis showed that it accumulates in high amounts in iron-loaded mitochondria of erythroblasts of subjects with impaired heme synthesis. This new ferritin may play an important role in the regulation of mitochondrial iron homeostasis and heme synthesis.

Haemolytic onset of Wilson disease in a patient with homozygous truncation of ATP7B at Arg1319

We describe a 19-year-old woman with haemolytic anaemia and thrombocytopenia as the initial manifestation of Wilson disease (WD). There are two reasons for reporting such an improbable case. First, it emphasizes the importance of recognizing atypical clinical presentations of potentially lethal recessive traits for which therapy is available. Second, it shows that, even in a monogenic disorder like WD, the phenotype cannot be extrapolated from the mutated genotype in a simple fashion; this patient had a relatively late-onset form of WD despite homozygosity for a genetic lesion leading to an apparent complete loss of function of the WD copper transporter.

Expression of p53, bcl-2 and ras oncoproteins and apoptosis levels in acute leukaemias and myelodysplastic syndromes

We analysed by immunocytochemistry the expression of p53, bcl-2 and ras proteins in bone marrow blasts from 59 patients with acute leukaemia (AL), 36 myeloid (AML) and 23 lymphoid (ALL), and from 22 patients with myelodysplastic syndrome (MDS); our aim was to examine if abnormalities in their expression were associated with peculiar biological and clinical findings, or with an altered apoptosis rate, as measured by TUNEL technique. The oncoproteins were expressed with extreme variability, without significant differences among the various morphological or immunological AL subtypes. The mean percentages of bcl-2+ blasts were significantly higher in AML than in MDS (p = 0.01), and in MDS with bone marrow blastosis than in the forms without excess of blasts (p = 0.007). The lowest percentages of apoptotic cells were observed in ALL (mean 1%, p = 0.006), whereas in MDS the apoptotic index was higher (16.7%) than in AML (8.6%) and than in the normal controls (10.8%). but the difference tended to be statistically significant only for cases of refractory anaemia. Whereas in AML and MDS the apoptotic rate was independent of the oncoprotein expression, in ALL there was a significant linear relationship between TUNEL and ras positivity (p = 0.01). Among AML patients treated with intensive polychemotherapy, no differences were observed in oncoprotein expression and apoptotic rate between responders and resistant cases. In conclusion, our data are in agreement with the hypothesis that decreased apoptosis and enhanced cell survival are associated with AL, whereas a high level of apoptosis may be responsible for the ineffective hematopoiesis in MDS; abnormal expression of oncoproteins, even if not strictly related to apoptosis level, may influence disease behaviour.

A modified high-dose dexamethasone regimen for primary systemic (AL) amyloidosis

High-dose dexamethasone (HD-Dex) has been reported to benefit AL amyloidosis patients with varying response rates. Our preliminary experience with the usual HD-Dex schedule indicated that the induction phase was rather toxic in AL patients. We therefore adopted a milder schedule consisting of dexamethasone 40 mg on d 1-4 q21 d for up to eight cycles. Overall 8 out of 23 (35%) treated patients responded to treatment in a median time of 4 months (range 2-6 months) without significant toxicity. This regimen may be considered front-line therapy when autologous stem cell transplantation is not feasible and when a rapid response is particularly important.

Clinical and biological features of acute myeloid leukaemia occurring as second malignancy: GIMEMA archive of adult acute leukaemia

Between July 1992 and June 1996, 3934 new cases of acute leukaemia were registered in the Gruppo Italiano Malattie Ematologiche Maligne dell'Adulto (GIMEMA) Archive of Adult Acute Leukaemia. Two hundred cases (5.1%) presented with a history of primary malignancy (PM), 179 of which were acute myeloid leukaemia (AML). The median age of these cases was significantly higher than that of other primitive AML (63 years vs. 57 years; P < 0.001). The number of men was significantly lower than the number of women [74/1544 (4.8%) vs. 105/1420 (7.4%); odds ratio (OR) 0.63, 95% confidence interval (CI) 0.46-0.87; P < 0.002], as was the number of patients aged <65 years [104/1963 (5.3%) vs. 75/1001 (7.5%); OR 0.69, 95% CI 0.50-0.95; P < 0.01]. An increased incidence of cancer was observed among first-degree relatives of patients with AML occurring after a PM (secondary AML; sAML) [66/179 (36.9%) sAML vs. 757/2785 (27.2%) de novo AML, age adjusted; OR 2.62, 95% CI 1.07-6.42; P < 0.005]. Prevalent types of PM were breast cancer, lymphoma and Hodgkin's disease. sAML occurred after a median latency of 52 months (range 2-379). Of the 122 patients who received chemotherapy for sAML, 67 patients (55%) achieved a complete remission (CR), three a partial remission, 15 (12%) died in induction and 37 (30%) were unresponsive. The median duration of CR was 30 weeks (range 4-250). The median overall survival was 7 months (range 1-196). Comparing acute promyelocytic leukaemia with all other French-American-British (FAB) groups, a significant increase in CR achievement was observed [14/18 (77.7%) vs. 53/101 (52.4%), P < 0.046] as well as in median CR duration (55 vs. 24 months, P < 0.02). The analysis of our data suggests that not only previous chemotherapy but also genetic predisposition could play a role in the pathogenesis of sAML.

Cord blood-derived hematopoietic progenitor cells: in vitro response to hematopoietic growth factors and their recruitment into the S-phase of the cell cycle

BACKGROUND AND OBJECTIVES

In the recent years many studies on the expansion of cord blood (CB)-derived progenitor cells have been performed, whereas less information is available on their cycling status. The objective of this study was to evaluate the cycling status of CB-derived colony-forming cells (CFC) and long-term culture-initiating cells (LTC-IC), and their recruitment into the S-phase of the cell cycle in response to a combination of cytokines.

DESIGN AND METHODS

CB-derived CFC and LTC-IC were first quantified by standard clonogenic assay and long-term culture, respectively. In a second set of experiments, CB-derived progenitor cells were incubated with interleukin(IL)-3, stem cell factor (SCF) and granulocyte colony-stimulating factor (G-CSF) and their cell cycle status assessed both by the cytosine arabinoside (Ara-C) suicide approach and by flow cytometric DNA analysis.

RESULTS

We found that only small proportions of both CFC and LTC-IC were in the S-phase of the cell cycle. These estimates were confirmed by flow cytometric DNA analysis, which showed that 96% +/- 2% of CB-derived CD34+ cells were in G0/G1 and only 1.6% +/- 0.4% in the S-phase. Staining of CD34+ cells with an anti-statin monoclonal antibody, a marker of the G0 phase, indicated that among CD34+ cells with a flow cytometric DNA content typical of the G0/G1 phase, 68% +/- 7% of cells were in the G0 phase of the cell cycle. Twenty-four hour incubation with IL-3, SCF and G-CSF significantly increased the proportion of cells in the S-phase for both CFC and LTC-IC without inducing any loss in their number. Flow cytometric DNA analysis also showed an increase of CD34+ cells in the S-phase upon continuous exposure to these cytokines.

INTERPRETATIONS AND CONCLUSIONS

Our findings indicate that: i) a small number of CB-derived CFC and LTC-IC are in the S-phase of the cell cycle; ii) a substantial number of CD34+ cells with a flow cytometric DNA content typical of the G0/G1 fraction are cycling, as they are found in the G1 phase of the cell cycle; iii) 24-hour incubation with IL-3, SCF and G-CSF can drive a proportion of progenitor cells into the S-phase without reducing their number.

Alpha-synuclein and Parkinson's disease: selective neurodegenerative effect of alpha-synuclein fragment on dopaminergic neurons in vitro and in vivo

Missense mutations in the alpha-synuclein gene were associated with a familial Parkinson's disease, and alpha-synuclein is a major component of Lewy bodies, the intracellular inclusions that neuropathologically characterize Parkinson's disease. We investigated the neurotoxic activity of the nonamyloid component (NAC) of senile plaque, the fibrillogenic fragment (61-95) of alpha-synuclein, in vitro and in vivo. Rat primary mesencephalic neurons were exposed for 6 days to low concentrations of preaggregated NAC (0.5-10.0 microM). The number of dopaminergic neurons and dopamine content were both reduced with no effect on the general viability of the cells. At higher concentrations (25-100 microM), the neurotoxic effect of NAC was extended to all neurons. Preaggregated NAC was also toxic on a PC12 dopaminergic cell line differentiated with nerve growth factor. The intracellular localization of NAC has been identified by the exposure of neuronal cells to fluorescent peptide. In vivo application of aggregated NAC in the substantia nigra induced loss of dopaminergic neurons. Our data illustrate the selective neurotoxic effect of NAC for dopaminergic neurons and support the central role of alpha-synuclein in the pathogenesis of Parkinson's disease.

Cell cycle distribution of cord blood-derived haematopoietic progenitor cells and their recruitment into the S-phase of the cell cycle

The objective of this study was to evaluate the cycling status of cord blood (CB)-derived colony-forming cells (CFC) and long-term culture-initiating cells (LTC-IC), and their recruitment into the S-phase of the cell cycle. By using the cytosine arabinoside (Ara-C) suicide approach, we found that only small proportions of both CFC and LTC-IC were in the S-phase of the cell cycle. These estimates were confirmed by flow cytometric DNA analysis, which showed that 96 +/- 2% of CB-derived CD34+ cells were in G0/G1 and only 1.6 +/- 0.4% in the S-phase. Staining of CD34+ cells with an antistatin monoclonal antibody, a marker of the G0 phase, indicated that among CD34+ cells with a flow cytometric DNA content typical of the G0/G1 phase 68 +/- 7% of cells were in the G0 phase of the cell cycle. Incubation (24 h) with interleukin 3 (IL-3), recombinant human stem cell factor (SCF) and granulocyte colony-stimulating factor (G-CSF) significantly increased the proportion of cells in the S-phase for both CFC and LTC-IC without inducing any loss in numbers. Flow cytometric DNA analysis also showed an increase in CD34+ cells in the S-phase upon continuous exposure to these cytokines. Our findings indicate that: (i) very few CB-derived CFC or LTC-IC were in the S-phase of the cell cycle; (ii) a substantial amount of CD34+ cells with a flow cytometric DNA content typical of the G0/G1 fraction was cycling, as found in the G1 phase of the cell cycle; and (iii) 24-h incubation with IL-3, SCF and G-CSF could drive a proportion of progenitor cells into the S-phase without reducing their number. These data might be useful for gene transfer protocols and the ex vivo expansion of CB-derived progenitor cells.

JL13, a pyridobenzoxazepine compound with potential atypical antipsychotic activity, increases extracellular dopamine in the prefrontal cortex, but not in the striatum and the nucleus accumbens of rats

In behavioral and receptor binding studies, 5-(4-methylpiperazin-1-yl)-8-chloro-pyridol[2,3b] [1,5]benzoxazepine (JL13) shows an atypical antipsychotic profile. We used microdialysis in awake rats to study the effects of various intraperitoneal doses of JL13 on extracellular concentrations of dopamine in the prefrontal cortex, nucleus accumbens and striatum. JL13 at 20 mg/kg and 40 mg/kg dose-dependently raised extracellular dopamine (234% and 434% of basal levels at peak, respectively) in the prefrontal cortex whereas lower doses (5 mg/kg and 10 mg/kg) had no effect. Extracellular concentrations of dihydroxyphenylacetic acid and homovanillic acid were also significantly increased in the prefrontal cortex of rats given 40 mg/kg JL13 (310% and 230% of basal levels, respectively). At 20 mg/kg and 40 mg/kg JL13 did not affect the extracellular concentrations of dopamine and its metabolites in the striatum and nucleus accumbens. The mechanisms by which JL13 increases cortical dopamine release and the significance for potential antipsychotic efficacy are discussed.

Acute lymphoblastic leukaemia occurring as second malignancy: report of the GIMEMA archive of adult acute leukaemia. Gruppo Italiano Malattie Ematologiche Maligne dell'Adulto

Between July 1992 and June 1996, 901 new cases of adult acute lymphoblastic leukaemia were recorded in the GIMEMA Archive of Adult Acute Leukaemia; 21 of them (2.3%) had a previous primary malignancy (PM). We found that secondary acute lymphoblastic leukaemia cases (sALL) presented with older age, a high incidence of pre-pre-B immunophenotype and a significantly higher prevalence of cancer among relatives compared to de novo ALL. The leukaemogenic activity of the cytotoxic drugs employed for the treatment of PM may have played a potential role in only a proportion of patients, opening the possibility that some sALL patients may have developed two or more malignancies due to individual predisposing factors.

Fluoxetine increases extracellular dopamine in the prefrontal cortex by a mechanism not dependent on serotonin: a comparison with citalopram

Fluoxetine at 10 and 25 mg/kg increased (167 and 205%, respectively) the extracellular dopamine concentration in the prefrontal cortex, whereas 25 (but not 10) mg/kg citalopram raised (216%) dialysate dopamine. No compound modified dialysate dopamine in the nucleus accumbens. The effect of 25 mg/kg of both compounds on cortical extracellular dopamine was not significantly affected by 300 mg/kg p-chlorophenylalanine (PCPA) (fluoxetine, saline, 235%; PCPA, 230%; citalopram, saline, 179%; PCPA, 181%). PCPA depleted tissue and dialysate serotonin by approximately 90 and 50%, respectively, and prevented the effect of fluoxetine and citalopram on dialysate serotonin (fluoxetine, saline, 246%; PCPA, 110%; citalopram, saline, 155%; PCPA, 96%). Citalopram significantly raised extracellular serotonin from 0.1 to 100 microM (251-520%), whereas only 10 and 100 microM increased dialysate dopamine (143-231%). Fluoxetine similarly increased extracellular serotonin (98-336%) and dopamine (117-318%). PCPA significantly reduced basal serotonin and the effects of 100 microM fluoxetine (saline, 272%; PCPA, 203%) and citalopram (saline, 345%; PCPA, 258%) on dialysate serotonin but did not modify their effect on dopamine (fluoxetine, saline, 220%; PCPA, 202%; citalopram, saline, 191%; PCPA, 211%). The results clearly show that the effects of fluoxetine and of high concentrations of citalopram on extracellular dopamine do not depend on their effects on serotonin.

The myelodysplastic syndromes: predictive value of eight prognostic systems in 143 cases from a single institution

BACKGROUND AND OBJECTIVE

Despite the fact that several prognostic systems for myelodysplastic syndromes (MDS) have been proposed, few studies have been designed to test their effectiveness in independent patient populations. The aim of this study was to compare the prognostic value of 8 previously described prognostic systems in a series of consecutive MDS patients observed at a single institution over a 10-year period.

DESIGN AND METHODS

One hundred and forty-three patients were diagnosed as having myelodysplastic syndrome (MDS) according to the French-American-British (FAB) criteria. They were studied retrospectively in order to assess the prognostic value of the FAB classification and 7 other prognostic systems.

RESULTS

On the basis of data at diagnosis, all investigated systems effectively stratified patients into groups with different life expectancies and identified a subset of patients with poor clinical outcome. However, the systems had different outcomes concerning median survival of patients classified as low-risk, ranging from less than 3 years for the Mufti scoring system to more than 8 years for the FAB classification modified according to Rosati et al. Moreover, patient distribution into different risk categories was quite different with the different prognostic systems.

INTERPRETATION AND CONCLUSIONS

When applied to our case series, some of the prognostic systems had a much lower prognostic value than in the patient population from which they derived. This evidence suggests that testing of prognostic systems in independent case series is necessary before using the systems in clinical practice.