Neurovascular alterations in bipolar disorder: A review of perfusion weighted magnetic resonance imaging studies

BACKGROUND

Bipolar Disorder (BD) is a severe chronic psychiatric disorder whose aetiology is still largely unknown. However, increasing literature reported the involvement of neurovascular factors in the pathophysiology of BD, suggesting that a measure of Cerebral Blood Flow (CBF) could be an important biomarker of the illness. Therefore, since, to date, Magnetic Resonance Perfusion Weighted Imaging (PWI) techniques, such as Dynamic Susceptibility Contrast (DSC) and Arterial Spin Labelling (ASL), are the most common approaches that allow non-invasive in-vivo perfusion measurements,this review aims to summarize the results from all PWI studies that evaluated the CBF in BD.

METHODS

A bibliographic search in PubMed up until May 2021 was performed. 16 PWI studies that used DSC or ASL sequences met our inclusion criteria.

RESULTS

Overall, the results supported the presence of hyper-perfusion in the cingulate cortex and fronto-temporal regions, as well as the presence of hypo-perfusion in the cerebellum in BD, compared with both healthy controls and patients with unipolar depression. CBF changes after cognitive and aerobic training, as well as in relation with other physiological, clinical, and neurocognitive variables were also reported.

LIMITATIONS

The heterogeneity across the studies, in terms of experimental designs, sample selection, and methodological approach employed, limited the studies' comparison.

CONCLUSIONS

These findings showed CBF alterations in the cingulate cortex, fronto-temporal regions, and cerebellum in BD, suggesting that CBF may be an important pathophysiological marker of BD that merits further investigation to clarify the extent of neurovascular alterations.

Neuroinflammation in Major Depressive Disorder: A Review of PET Imaging Studies Examining the 18-kDa Translocator Protein

BACKGROUND

Major Depressive Disorder (MDD) is a severe psychiatric disorder whose pathological mechanisms are largely unknown. In the field of immuno-psychiatry, several evidences suggested a prominent role of inflammation in MDD not only in peripheral immune system but also in the brain. To date, brain inflammation is traceable in vivo with Positron Emission Tomography (PET), through the quantification of the expression of 18-kda Translocator Protein (TSPO) by active microglia. In this context, this review aimed to summarize the results of all in vivo PET imaging studies that evaluated microglia activation in MDD.

METHODS

A bibliographic search in PubMed up to June 2020 was performed. A total of 9 studies that used first and second generation TSPO radiotracers met our inclusion criteria.

RESULTS

Overall the results suggested the presence of TSPO upregulation in MDD, especially in anterior cingulate cortex, prefrontal cortex, hippocampal formation and insula. Notably, from a therapeutic point of view, results suggested that the symptoms amelioration, caused by both antidepressant medication and cognitive behavioural therapy, may be accompanied by reduced inflammatory status in the brain. Finally, a positive effect of the anti-inflammatory treatment with a cyclooxygenase inhibitor has also been observed.

LIMITATIONS

The heterogeneity across the studies in experimental designs, sample selection and methods limited the studies comparison.

CONCLUSIONS

These findings supported the presence of neuroinflammation in MDD, suggesting that microgliosis may be an important pathophysiological mechanism that merits further investigation as a potential target for novel treatment strategies.

Brick-by-brick inequality. Homeownership in Italy, employment instability and wealth transmission

This paper investigates changes between, and inequalities within, birth-cohorts in Italy, surrounding homeownership. Italy is a homeownership and familialistic society, where in recent decades an increasing 'generational divide' in employment prospects has opened up, as a side-effect of a partial and targeted labour market deregulation. Drawing on the interplay of macro-level constraints with micro-level factors, we discuss patterns of inequality in attaining homeownership between cohorts, arising from greater instability of employment for young adults, and within cohorts, stemming from class-based patterns of intergenerational wealth transmission. Our analytical strategy combines a sequential cohort design with two levels of analysis that simultaneously consider young people around the normative age of housing independence and wealth transmission from their families triggered by their leaving the nest. Longitudinal analyses apply random-effects probit models and linear probability distributed fixed-effects to panel data from the Bank of Italy (SHIW 1989-2016). Results show a decrease in homeownership attainment across cohorts, which can be partially ascribed to employment disadvantages faced by younger cohorts. On top of this, class-specific patterns of intergenerational transmission are in place: lower classes rely on timely housing wealth transfers, whereas upper classes are prepared to provide their children with an extended stream of financial transfers.

Cognitive Remediation for Inpatients With Schizophrenia: Effects of a Brief and Intensive Training

Computer-assisted cognitive remediation (CACR) is a computer-based rehabilitation treatment aimed at improving cognition and at developing strategies that can be applied to various functional areas. Different protocols are currently used with great variability over the intensity and duration of treatments. In this study, we evaluated the effects of a brief and intensive CACR training (i.e., 15 sessions for 3 weeks) on cognitive domains, as well as the durability of cognitive gains and their generalization to functional areas, 3 months after CACR training. Thirty-eight patients with schizophrenia were recruited and assessed for psychopathology, cognitive performance, and functioning before the rehabilitative intervention. Patients were reassessed for cognition after CACR rehabilitation. Moreover, a subsample of 13 patients was evaluated for cognition and functioning 3 months after CACR completion. Results show significant improvements in multiple cognitive domains after CACR. Furthermore, 3 months after CACR completion, significant improvements were also detected in executive functions and daily functioning. This study suggests that a brief and intense CACR training is effective on cognitive and functional domains and that it could be feasible and affordable for health care services, thus offering patients the best options for fulfilling recovery goals.

Sexual Dimorphism in the Brain Correlates of Adult-Onset Depression: A Pilot Structural and Functional 3T MRI Study

Major Depressive Disorder (MDD) is a disabling illness affecting more than 5% of the elderly population. Higher female prevalence and sex-specific symptomatology have been observed, suggesting that biologically-determined dimensions might affect the disease onset and outcome. Rumination and executive dysfunction characterize adult-onset MDD, but sex differences in these domains and in the related brain mechanisms are still largely unexplored. The present pilot study aimed to explore any interactions between adult-onset MDD and sex on brain morphology and brain function during a Go/No-Go paradigm. We hypothesized to detect diagnosis by sex effects on brain regions involved in self-referential processes and cognitive control. Twenty-four subjects, 12 healthy (HC) (mean age 68.7 y, 7 females and 5 males) and 12 affected by adult-onset MDD (mean age 66.5 y, 5 females and 7 males), underwent clinical evaluations and a 3T magnetic resonance imaging (MRI) session. Diagnosis and diagnosis by sex effects were assessed on regional gray matter (GM) volumes and task-related functional MRI (fMRI) activations. The GM volume analyses showed diagnosis effects in left mid frontal cortex (p < 0.01), and diagnosis by sex effects in orbitofrontal, olfactory, and calcarine regions (p < 0.05). The Go/No-Go fMRI analyses showed MDD effects on fMRI activations in left precuneus and right lingual gyrus, and diagnosis by sex effects on fMRI activations in right parahippocampal gyrus and right calcarine cortex (p < 0.001, ≥ 40 voxels). Our exploratory results suggest the presence of sex-specific brain correlates of adult-onset MDD-especially in regions involved in attention processing and in the brain default mode-potentially supporting cognitive and symptom differences between sexes.

The association of autistic traits with Theory of Mind and its training efficacy in patients with schizophrenia

Literature has recently identified a discrete subgroup of patients affected by schizophrenia that also present autistic traits (ATs), showing a peculiar cognitive, clinical and functional profile. Theory of Mind (ToM) represents a core, impaired feature in both schizophrenia and Autism Spectrum Disorder (ASD), ToM in patients with schizophrenia and ATs has yet to be investigated. Thus, this study aims, on the one hand, to assess differences among patients with and without ATs on clinical, cognitive and ToM abilities as well as in daily functioning; on the other hand, to compare the efficacy on mentalizing abilities of a specific ToM training in these two groups.

Ninety-six patients with schizophrenia were enrolled and underwent a broad cognitive, social-cognitive and functional assessment before and after the ToM training.

ANOVAs revealed that patients with schizophrenia and ATs are more impaired in cognition, ToM, in premorbid and daily functioning as well as in clinical features, as compared to patients without ATs. This latter group also showed a general improvement in mentalizing abilities after ToM training, while patients with schizophrenia and ATs did not, with a significant time × group interaction on ToM abilities.

These data shed new light on the relation among schizophrenia and ATs, highlighting that patients with these traits are highly impaired in ToM abilities. Thus, ATs seem to limit the effectiveness of ToM training, having implications in clinical and rehabilitative practice.

HLA and Hypocomplementemia: The Disadvantage of Carrying the HLA-B35 and the Silent Alleles of the C4 Complement Component

Hypocomplementemia is an extremely complex phenomenon: we devoted our attention to its immunogenetic basis, particularly to the HLA haplotypes involved and to the study of C4 polymorphic genes. With this in mind we analyzed a group of unrelated patients with hypocomplementemia and 15 families suffering from specific C4 deficiency. Firstly, we performed a population analysis in order to identify a statistically significant association: HLA-B35 and C4BQ0 alleles, in the total group of hypocomplementemic individuals, seem to be associated with the primary disease.

Secondly, we defined HLA haplotypes clear-cut segregation in the hypocomplementemic families and we identified the most common HLA haplotypes carrying B35 and C4 null allele associated with this condition. With the aid of correspondence analysis and the Transmission Disequilibrium Test (TDT), we measured the strength of this association. In this work, mainly through family analysis, we envisaged a potentially interesting genomic trait, within HLA, close to B locus, that seems to be involved in hypocomplementemia itself and perhaps in hypocomplementemia-related disorders.

Antioxidant vitamins reduce oxidative stress and ventricular remodeling in patients with acute myocardial infarction

We analyzed soluble vascular adhesion molecules (sVCAM-1), reactive oxygen metabolites (ROMs) level, total antioxidant status (TAS) and telediastolic left ventricular volume (TLVV) in patients with myocardial infarction undergoing reperfusion therapy and treated with antioxidant vitamins (AT) or placebo (P) before and for 1 month after reperfusion. After reperfusion, sVCAM-1 serum concentration, reactive oxygen metabolites level, and TLVV were significantly higher in patients treated with placebo than in those treated with antioxidant vitamins, while TAS was significantly higher in patients treated with antioxidant supplementation. We observed that 48 hours after reperfusion sVCAM-1 (P) vs sVCAM-1 (AT) was 2.03+/-0.5 vs 1.63+/-0.7 microg/ml with p < 0.01; ROMs (P) vs ROMs (AT) were 335.60+/-35.80 vs 307.50+/-47.10 U.CARR with p < 0.05; TAS (P) vs TAS (AT) was 526.47+/-44.24 vs 737.65+/-51.15 micromol/l with p < 0.01; 1 week after reperfusion TLVV (P) vs TLVV (AT) was 125.12+/-29.80 vs 119.40+/-29.40 ml with p < 0.05; 1 month after reperfusion TLVV (P) vs TLVV (AV) was 132.00+/-33.50 vs 123.40+/-21.60 ml with p < 0.05. In the first period after infarction, vitamin treatment improves the antioxidant system and reduces oxidative stress, inflammatory process and left ventricular remodeling.

Immunological features of neurological paraneoplastic syndromes

Neurological paraneoplastic syndromes are a rare group of disorders that occur in 1-2% of people with malignancy. They are usually caused by an immune response, triggered by and directed against a tumour, that cross-reacts with protein expressed by the peripheral or central nervous system. Any part of the nervous system can be affected and patients often develop severe and permanent disability. Diagnosis can be difficult as in two-thirds of patients the neurological problems appear up to 5 years before the tumour manifests. However, certain of these syndromes are often associated with specific serum autoantibodies that can be useful both in diagnosis of the neurological syndrome and in focusing the search for a particular tumour. Thus, these antibodies can allow earlier identification and treatment of cancer and, potentially, a reduction in morbidity and mortality. It was only in the 1980s that the first anti-neuronal autoantibodies were characterized and their associations with clinical syndromes and tumours defined. Further antibodies have been isolated over the past 20 years and novel pathogenic mechanisms for several syndromes have been recognized. For example, voltage-gate ion channels seem to be a common target for autoantibodies involved in peripheral nerve diseases such as the Lambert-Eaton myasthenic syndrome and neuromyotonia (Isaacs' syndrome). However, the place of most paraneoplastic antibodies in the pathogenesis of central syndromes is yet to be fully elucidated.

Attenuation of leukocyte beta 2-integrin expression by antithrombin-III

Antithrombin-III exerts antiinflammatory effects via ligation of heparan sulfate proteoglycans. Here we show in vitro that recombinant human antithrombin-III attenuates CD11b/CD18 expression of activated neutrophils and monocytes in whole blood ex vivo. As leukocyte integrin expression is triggered by extracorporeal circulation, this observation may be of relevance for pharmacological treatment during cardiopulmonary bypass.

Plasma levels of procalcitonin and interleukin-6 in acute myocardial infarction

Estimation of cardiac morbidity in patients after major surgery is a difficult problem. In addition, infectious complications seriously decrease potential beneficial outcome after cardiovascular surgery. The present study assessed the use of a newer marker of the inflammatory response, procalcitonin, in the field of myocardial infarction, in conjunction with measurements of interleukin-6. Forty-four consecutive cases with acute myocardial infarction were included in the study 4+/-1.3 h after the onset of symptoms. Plasma levels of procalcitonin and interleukin-6 were obtained at admission, and after 3, 6, 12, 18, 24 and 48 h, using commercially available test kits. The range of levels of interleukin-6 and procalcitonin was about normal at admission. Interleukin-6 levels increased significantly following myocardial infarction, whereas procalcitonin were essentially unchanged, i.e. remained close to the normal level threshold of 0.5 ng/ml; only minor variability occurred with a mean peak level of procalcitonin of 1+/-0.4 ng/ml. Data demonstrate that, in contrast to the acute phase reactant interleukin-6, plasma levels procalcitonin are not significantly elevated during uncomplicated acute myocardial infarction. This observation may support the role of procalcitonin measurements in the differential diagnosis of infectious and cardiovascular complications after major surgery.

Single molecule detector for mass spectrometry with mass independent detection efficiency

Experimental results from equimolar PEG and protein standards samples are presented from a MALDI-TOF mass spectrometer equipped with both ionizing detectors and the novel single molecule sensitive cryodetectors. The data are consistent with a model hypothesis suggesting that the observed decrease in signal strength in conventional ionizing detector MALDI-TOF mass spectrometers can be explained by the exponentially decreasing quantum efficiency of ionizing detectors. Cryodetectors, in contrast, have a mass independent detection efficiency of 100% on impact and provide additional information on the molecule state owing to the calorimetric nature of the detection mechanism.

Plasma levels of interleukin 2, 6, 10 and phenotypic characterization of circulating T lymphocytes in ischemic heart disease

The purpose of this study was to assess lymphocyte receptors expression in patients with ischemic heart diseases, as well as to measure the plasma levels of interleukin (IL) 2, 6 and 10. T Lymphocytes are found in large numbers in human atherosclerotic plaques, indicating that immune and inflammatory mechanisms are important factors in the pathogenesis of atherosclerosis. Recent data have also implicated T lymphocytes in the pathogenetic mechanism of unstable angina and ischemic heart disease. Three groups of patients were studied: 42 with an acute ischemic syndrome (AIS), 36 with stable angina (SA) and 39 healthy controls. To characterize lymphocyte phenotype, flow cytometry was performed in whole-blood samples. IL-2, IL-6 and IL-10 were measured using the ELISA method. Double fluorescence evaluation showed an increase in CD8+/CD11b+ cells (cytotoxic T lymphocytes) and in CD11b+/CD16+CD56+ cells (NK lymphocytes) in the AIS group and in SA group as compared to the control group (P < 0.05 and P < 0.001, respectively). IL-2 was increased in the AIS and SA groups compared to the control group (AIS 4.5 +/- 0.5 pg/ml; SA 6.3 +/- 0.6 pg/ml; controls 2.4 +/- 0.8 pg/ml, P < 0.05), whereas IL-6 was higher in the AIS group than in the other two groups (AIS 10.8 +/- 1.8 pg/ml; SA 1.8 +/- 0.8 pg/ml; controls 1.2 +/- 0.6 pg/ml, P < 0.0001). These data show that patients with ischemic heart disease have an increase in circulating cytotoxic T lymphocytes and in IL-2 plasma levels, irrespective of their clinical presentation, compared to normal control subjects, whereas IL-6 is elevated only in patients with AIS.

The effects of iloprost infusion on microcirculation is independent of nitric oxide metabolites and endothelin-1 in chronic peripheral ischaemia

BACKGROUND

Endothelial vascular tone modulators are thought to be involved in aetiopathogenesis of systemic sclerosis (SS) and of peripheral artery occlusive disease (PAOD). Iloprost, a prostacyclin (PGI2) analogue, induces clinical benefit in patients suffering from peripheral ischaemia. This study was performed to investigate the effect of this drug on endothelial function in vivo to elucidate the role of vascular tone modulators.

METHODS

Fourteen PAOD and 15 SS patients were treated for 24 and 10 days respectively. On the first day, before and after therapy, nitric oxide metabolites (NO2-/NO3-) and endothelin-1 (ET-1) plasma concentrations were detected; moreover, the endothelium-dependent vasodilatation in response to artificial ischaemia was evaluated by means of an echo-Doppler device.

RESULTS

The echo-Doppler evaluation showed that the percentage of arterial reactive dilatation was not modified by placebo or by iloprost, and that the increase in blood velocity flow lasted for a significant longer time after drug infusion (226.79 +/- 17.49 vs. 310.71 +/- 36.32 s; P > 0.04). NO2-/NO3- and ET-1 plasma concentration were higher in patients than in control subjects (P < 0.004). After 6 h of iloprost infusion, no significant modifications were detected.

CONCLUSION

This study provides evidence that iloprost enhances the microvascular functional capacity and clinical benefit for patients. The effects of the drug seem to be independently or not directly correlated with its interactions with vascular tone modulators such as NO2-/NO3- or ET-1.

In vitro effects of GM-CSF on mature peripheral blood neutrophils

GM-CSF can play a crucial role in regulating the neutrophil-mediated inflammatory response. This growth factor is a proliferative stimulus for bone marrow neutrophil stem cell precursors and has at least 3 important roles in regulating neutrophil-mediated immunity: a) a direct effect on the proliferation and development of neutrophil progenitors; b) synergistic activity with other haemopoietic growth factors; c) stimulation of the functional activity of mature neutrophils. The production of GM-CSF may be triggered directly by exogenous factors such as antigens and endotoxins, or indirectly through the release of cytokines by a variety of cells including lymphocytes, activated macrophages and endothelial cells exposed to products of mononuclear phagocytes. Such production of GM-CSF may serve to quickly release mature neutrophils from the bone marrow in response to infections. Moreover, enhancement of the function of mature neutrophils may also augment their ability to migrate to infective sites and then phagocytose and kill pathogens. Increased expression of CD11b/CD18 may play a fundamental part in this mechanism because this receptor is essential for the adhesion of neutrophils to the endothelium. Both phagocytosis and oxidative burst activity increase as a result of the action of GM-CSF and the increased expression of complement- and Fc-receptors can augment opsono-phagocytosis. A further level of neutrophil up-regulation occurs by increasing the functional life span of neutrophils by GM-CSF. Thus, by delaying neutrophil apoptosis, GM-CSF greatly extends the time over which neutrophils may function at inflammatory sites. GM-CSF can thus exert a variety of important regulatory controls of neutrophil function during bacterial infections. Both the number and the functional status of neutrophils is highly regulated by GM-CSF. It is also possible that GM-CSF produced within localised sites of acute inflammation or infection may attract, trap and then activate neutrophils within this site.

[beta-Interferon therapy of chronic hepatitis HCV+, 1b genotype]

Various papers reported that chronic viral hepatitis is the principal cause of chronic liver disease, as cirrhosis and hepatocarcinoma. Interferon is the only agent known to have a beneficial effect in chronic hepatitis. The response rate has been less than 10 percent in patients with genotype 1b, but in patients with genotype 2 or 3 it has been greater than 40 percent. Aim of our investigation was to study 10 patients suffering from chronic viral hepatitis HCV related, genotype 1b, non responder to interferon-alpha therapy. In these patients we administered beta-interferon at the dose of 6 million units, 3 times a week, for 3 months. A significant reduction of aminotransferase level was reported after 3 months of the start of the therapy. An higher level of beta-interferon plasma rate was found in 3 non responder patients. The interaction of beta-interferon with the immune system was demonstrated with an increase of CD8+ lymphocytes that correlated with decrease of HCVRNA. The treatment with beta-interferon have a beneficial effect in patients with chronic hepatitis HCV related, genotype 1b, no responder to interferon-alpha therapy.

Expression of adhesion molecules and functional stimulation in human neutrophils: modulation by GM-CSF and role of the Bcr gene

Although devoid of proliferative capacity, polymorphonuclear neutrophils (PMN) express receptors for haemopoietic growth factors and need growth factors for survival and functional stimulation. This study showed that in vitro treatment of human PMN with GM-CSF for up to 48 h increases cell surface expression of the beta 2-integrin molecules CD11b/CD18 and CD11c/CD18 and of the receptor for the chemotactic peptide fMLP. Such modifications are usually expression of PMN activation. PMN treated with GM-CSF also displayed increased phagocytosis of latex particles and enhanced oxidative burst and superoxide anion release. Since integrins mediate PMN adhesion to endothelium, homotypic adhesion, chemotaxis/phagocytosis and the triggering of respiratory burst, our results suggested that functional stimulation of PMN persisted following prolonged exposure of PMN to growth factors and that it was not a temporary phenomenon which lasted only for the first 12-24 h of treatment. We also used oligonucleotides antisense to the Bcr gene mRNA to inhibit expression of the gene and evaluate its function in PMN, following the recent observation that PMN from Bcr-null mutant mice produced increased amounts of reactive oxygen metabolites upon activation. The antisense oligonucleotides had no effect on the parameters investigated. This may indicate that increased production of O2 by neutrophils in which the Bcr gene is not expressed requires either that gene expression is absent in the earlier stages of myeloid differentiation/maturation, so that when inhibition occurs in the terminally differentiated neutrophils their functional status is no longer influenced, or that the residual low-level expression of the gene which may be present in the antisense-treated cells is sufficient to provide a normal response to stimulation.

Increased expression of CD11b/CD18 on phagocytes in ischaemic disease: a bridge between inflammation and coagulation

The aim of this study was to assess the expression of CD11b/CD18 integrin adhesion molecules on the phagocytes of patients with ischaemic diseases, and to evaluate the concentration of soluble adhesion molecules that are released from endothelium (sICAM-1) and from phagocytes (sL-selectin). A total of 370 patients were enrolled: 120 with coronary artery disease (CAD); 50 with peripheral artery occlusive disease (PAOD); and 200 control subjects with no clinical manifestations of ischaemic disease. CD11b/CD18 integrin was detected by flow cytometry, whereas sL-selectin and sICAM-1 concentrations were detected using a sandwich-type immunoassay. CD11b/CD18 integrin expression was found to be higher in the patients with ischaemic disease than in the control subjects (P < 0.001). The PAOD patients had higher values of CD11b/CD18 integrin than the CAD ones (P < 0.01). The concentration of soluble adhesion molecules did not show any significant differences within the three groups (P = NS). The high expression of CD11b/CD18 integrin in ischaemic disease patients may depend on the increased, but probably stable, cytokine network that has been demonstrated to occur in chronic ischaemic diseases: the difference observed between PAOD and CAD patients could be the consequence of higher inflammatory activation probably resulting from the greater extent of the atherosclerotic process in PAOD, or of the more localized ischaemic area in CAD patients. CD11b/CD18 can therefore be considered a marker of chronic phagocyte activation during ischaemic disease. On the other hand, sICAM and sL-selectin concentrations were found to be within the normal range; they have recently been considered as a marker for acute ischaemic events and acute inflammatory process activation. Our results confirm that in uncomplicated atherosclerosis no acute inflammatory process activation should occur.

[Opioid receptors and phagocyte defects in drug addicts]

In order to better elucidate the immunological effect of opioid abuse in the absence of HIV infection as a confounding factor, granulocyte function was investigated in 3 groups of HIV negative subjects including 20 active parenteral heroin abusers (E), 20 long-treatment methadone-maintained former opiate abusers (M) and 20 healthy controls. Chemotaxis to fMLP, casein and activated plasma were markedly and similarly reduced (approximately 50%) in both E and M groups, as true for superoxide production after fMLP and PMA stimulation, 47% decrease of C values. PMNs of E and M subjects also exhibited a very marked and similar reduction in the expression of CD11b/CD18 integrin receptors after fMLP treatment with values that were lower than 10% of those in controls as observed by flow cytometry. In parallel, PMNs of E and M individuals presented an approximately four fold increase in opioid receptors number compared to controls, a significant inverse correlation existing between the increase in opiate receptors and defective chemotaxis. The possible mechanism retaining the observed changes in PMNs of E and M individuals are discussed.

Granulocyte dysplasia and dysfunction, and CD11/CD18 defects in myelodysplastic syndromes

In myelodysplastic syndromes (MDS), dysplastic changes in neutrophils are a common feature reflecting the total degree of bone marrow dysplasia. Furthermore, granulocyte function is abnormal, so that a high risk of life-threatening infections has been documented. In this review we shall focus on the defects of both granulocytes and their CD11b/CD18 glycoprotein complex, which regulate granulocyte adherence, locomotion, diapedesis and migration into inflammatory sites, in patients suffering from primary MDS. The defective surface membrane glycoprotein expression of myelodysplastic phagocytes is not only a useful diagnostic tool, but also a powerful prognostic one, since MDS patients with such defects present both an increased susceptibility to infections and a decreased survival. Moreover, the administration of colony-stimulating factors is known to be able to elicit long-lasting improvement in neutrophil count, CD11b/CD18 expression and function, marrow myeloid maturation, and possibly to decrease bacterial infections in MDS patients.

Iloprost effects on phagocytes in patients suffering from ischaemic diseases: in vivo evidence for down-regulation of alpha M beta 2 integrin

This study has been designed to demonstrate the in vivo effects of iloprost therapy on expression of adhesion molecules on phagocytes. Sixty patients suffering from peripheral arterial occlusive disease (PAOD) and/or from skin ulcers due to secondary progressive systemic sclerosis (PSS) were enrolled in a double-blind controlled parallel study. Thirty patients (group I) underwent iloprost infusion and 30 patients (group II) were treated with aspirin. Clinical assessment and measurement of phagocyte activation in vivo, using quantitative flow cytometry, were performed on entry and after 6 h on the first day of therapy. After 3 months of therapy, complete healing of all cutaneous lesions was observed in 84% of the patients treated with iloprost compared with the control patients (P < 0.001). Neutrophils and monocytes of PAOD and PSS patients showed a significant decrease in the expression of the alpha M beta 2 integrin adhesion receptor after 6 h of iloprost infusion. Neutrophils and monocytes released a lower amount of anion superoxide (O2-) after 6 h of iloprost treatment. These data confirm other clinical observations but demonstrate that in vivo this drug modifies the expression of the alpha M beta 2 integrin of phagocytes that has a key role in leukocyte-endothelium interactions in cases of inflammation and thrombosis.

Clinical and angiographic correlates of leukocyte activation in unstable angina

OBJECTIVES

This study sought to evaluate the relation, if any, between clinical and angiographic findings in patients with unstable angina and monocyte and neutrophil CD11b/CD18 receptor density. The expression of HLA-DR molecules on T lymphocytes, an index of activation of these cells, was also investigated.

BACKGROUND

Although activation of neutrophils and monocytes has recently been shown in unstable angina, no studies have correlated activation indexes with clinical and angiographic features of patients with this clinical condition.

METHODS

Sixty patients underwent diagnostic coronary arteriography and simultaneous blood sampling from the aorta and coronary sinus before injection of contrast medium. Cell surface receptors were detected by direct immunofluorescence evaluated by flow cytometry using monoclonal antibodies tagged with fluorescent markers.

RESULTS

In 38 patients with unstable angina, neutrophils and monocytes showed a significantly higher expression of CD11b/CD18 adhesion receptors in coronary sinus than aortic blood (p < 0.0001 and p < 0.001, respectively). When these patients were analyzed according to clinical characteristics or angiographic findings, no difference in CD11b/CD18 receptor expression in coronary sinus blood was found between the various subgroups, except for patients with at least one episode of chest pain at rest within 48 h of coronary arteriography and a higher neutrophil adhesion molecule density than patients who remained asymptomatic (p = 0.04). Lymphocytes in patients with stable and unstable angina showed a similar percent expression of CD2/CD19 and CD3/HLA-DR antigens, with no difference between aortic and coronary sinus blood.

CONCLUSION

These results in a larger cohort confirm previous data that neutrophil and monocyte CD11b/CD18 adhesion molecules show a higher expression in the coronary sinus blood of patients with unstable angina. Among clinical and angiographic findings in patients with unstable angina, only the occurrence of chest pain within 48 h of coronary angiography was related to significantly higher values of neutrophil fluorescence intensity, suggesting that the degree of neutrophil activation is related to the proximity of rest angina episodes to blood sampling. Finally, our data do not support the concept of systemic or transcardiac lymphocyte activation in unstable angina.

Granulocyte defects and opioid receptors in chronic exposure to heroin or methadone in humans

In order to elucidate better the immunological effect of opioid abuse in the absence of HIV infection as a confounding factor, granulocyte function was investigated in three groups of HIV-negative subjects, including 20 active parenteral heroin abusers (H), 20 long-term methadone-maintained former opiate abusers (M) and 20 healthy controls (C). Chemotaxis to N-formyl methionyl-leucyl-phenylalanine (fMLP), casein and activated plasma were markedly and similarly reduced (approx. 50%) in both H and M groups, as was true for superoxide production after fMLP and PMA stimulation, 47% decrease of C values. Polymorphonuclear (PMN) of H and M subjects also exhibited a very marked and similar reduction in the expression of CD11b/CD18 integrin receptors after fMLP treatment, with values that were less than 10% of those in controls, as observed by flow cytometry. In parallel, PMN of H and M individuals presented an approximately four-fold increase in opioid receptors numbers compared to controls, a significant inverse correlation existing between the increase in opiate receptors and defective chemotaxis. The possible mechanism underlying the observed changes in PMN of H and M individuals is discussed.