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Objective: Because dysregulated Epstein-Barr virus (EBV)-infected B cells may induce meningeal inflammation, which contributes to cortical pathology in multiple sclerosis (MS), we investigated associations between antibody responses to EBV and development of cortical pathology in MS., Methods: We included 539 patients with MS (369 with relapsing-remitting MS, 135 with secondary progressive MS, and 35 with primary progressive MS), 66 patients with clinically isolated syndrome (CIS), 63 patients with other neurologic diseases (OND), and 178 age- and sex-matched healthy controls (HC). All participants were scanned on 3T MRI. Serum samples were analyzed for IgG antibodies against EBV viral capsid antigen (VCA) and EBV nuclear antigen-1 (EBNA-1), and their quartiles were determined on the whole study sample. Differences between the study groups were assessed using analysis of covariance adjusted for multiple comparisons., Results: More than 30% of patients with MS and CIS presented with the highest quartile of anti-EBV-VCA and -EBNA-1 status compared to ≤10% of HC (p < 0.001). The figures were 9 (14.3%) and 7 (12.3%) for patients with OND. Patients with MS with the highest quartile of anti-EBV-VCA showed significantly increased T2 lesion volume (p = 0.001), T1 lesion number (p = 0.002), and T1 lesion volume (p = 0.04) and decreased gray matter (p = 0.041) and cortical (p = 0.043) volumes compared to patients with MS with lower quartiles. No significant differences of MRI outcomes in patients with CIS, patients with OND, and HC with lower or highest quartiles of anti-EBV-VCA and -EBNA-1 were detected., Conclusions: Humoral response to anti-EBV-VCA and -EBNA-1 is associated with more advanced cortical atrophy, accumulation of chronic T1 black holes, and focal white matter lesions in patients with MS.

Unlabelled: To compare frequencies of autoreactive antibody responses to endogenous disease-associated antigens in healthy controls (HC), relapsing and progressive MS and to assess their associations with clinical and MRI measures of MS disease progression., Methods: The study analyzed 969 serum samples from 315 HC, 411 relapsing remitting MS (RR-MS), 128 secondary progressive MS (SP-MS), 33 primary progressive MS (PP-MS) and 82 patients with other neurological diseases for autoantibodies against two putative MS antigens CSF114(Glc) and KIR4.1a and KIR4.1b and against 24 key endogenous antigens linked to diseases such as vasculitis, systemic sclerosis, rheumatoid arthritis, Sjogren's syndrome, systemic lupus erythematosus, polymyositis, scleroderma, polymyositis, dermatomyositis, mixed connective tissue disease and primary biliary cirrhosis. Associations with disability and MRI measures of lesional injury and neurodegeneration were assessed., Results: The frequencies of anti-KIR4.1a and anti-KIR4.1b peptide IgG positivity were 9.8% and 11.4% in HC compared to 4.9% and 7.5% in RR-MS, 8.6% for both peptides in SP-MS and 6.1% for both peptides in PP-MS (p = 0.13 for KIR4.1a and p = 0.34 for KIR4.1b), respectively. Antibodies against CSF114(Glc), KIR4.1a and KIR4.1b peptides were not associated with MS compared to HC, or with MS disease progression. HLA DRB1*15:01 positivity and anti-Epstein Barr virus antibodies, which are MS risk factors, were not associated with these putative MS antibodies., Conclusions: Antibody responses to KIR4.1a and KIR4.1b peptides are not increased in MS compared to HC nor associated with MS disease progression. The frequencies of the diverse autoreactive antibodies investigated are similar in MS and HC.

Background: Oxysterols are promising biomarkers of neurodegenerative diseases that are linked with cholesterol and vitamin D metabolism. There is an unmet need for methods capable of sensitive, and simultaneous quantitation of multiple oxysterols, vitamin D and cholesterol pathway biomarkers., Methods: A method for simultaneous determination of 5 major oxysterols, 25-hydroxy vitamin D3 and cholesterol in human plasma was developed. Total oxysterols were prepared by room temperature saponification followed by solid phase extraction from plasma spiked with deuterated internal standards. Oxysterols were resolved by reverse phase HPLC using a methanol/water/0.1% formic acid gradient. Oxysterols and 25-hydroxy vitamin D3 were detected with atmospheric pressure chemical ionization mass spectrometry in positive ion mode; in-series photodiode array detection at 204nm was used for cholesterol. Method validation studies were performed. Oxysterol levels in 220 plasma samples from healthy control subjects, multiple sclerosis and other neurological disorders patients were quantitated., Results: Our method quantitated 5 oxysterols, cholesterol and 25-hydroxy vitamin D3 from 200 μL plasma in 35 minutes. Recoveries were >85% for all analytes and internal standards. The limits of detection were 3-10 ng/mL for oxysterols and 25-hydroxy vitamin D3 and 1 μg/mL for simultaneous detection of cholesterol. Analytical imprecision was <10 %CV for 24(S)-, 25-, 27-, 7α-hydroxycholesterol (HC) and cholesterol and ≤15 % for 7-keto-cholesterol. Multiple Sclerosis and other neurological disorder patients had lower 27-hydroxycholesterol levels compared to controls whereas 7α-hydroxycholesterol was lower specifically in Multiple Sclerosis., Conclusion: The method is suitable for measuring plasma oxysterols levels in human health and disease. Analysis of human plasma indicates that the oxysterol, bile acid precursors 7α-hydroxycholesterol and 27-hydroxycholesterol are lower in Multiple Sclerosis and may serve as potential biomarkers of disease.

Context: High serum cholesterol is adversely associated with clinical and imaging disease progression outcomes in multiple sclerosis (MS) and in clinically isolated syndrome (CIS), the earliest stage of MS. Low vitamin D levels are associated with an increased risk of disease progression., Objectives: To investigate the mechanisms mediating the adverse effects of cholesterol in CIS and to determine the role of the nexus between the vitamin D3 (D3) and cholesterol pathways., Design: Multi-center, prospective, longitudinal prospective study., Setting: University hospital multiple sclerosis centers., Intervention: Serum samples were obtained prior to any treatment from study subjects., Methods: Serum obtained prior to any treatment from 172 CIS patients enrolled in a multi-center, prospective, longitudinal study (119 females: 53 males, age: 28.1 ± SD 8.1 years) were analyzed for high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), apolipoprotein AI (ApoAI), ApoAII, ApoB, ApoE, and lipoprotein-a. Levels of 25-hydroxy vitamin D3 (25(OH)D3), 1,25-dihydroxy D3, and 24,25-dihydroxy D3 were measured using liquid chromatography-mass spectrometry., Results: Greater levels of HDL-C biomarkers (e.g., HDL-C itself, ApoAI, ApoAII and paroxonase arylesterase activity) and LDL-C biomarkers (e.g., LDL-C itself, Apo B) were associated with greater 25(OH)D3. The effects of HDL-C biomarkers were stronger than those of LDL-C. Free cholesterol and cholesteryl ester levels were positively associated with higher 25(OH)D3 levels. Cholesterol palmitate was particularly potent. The nexus between the D3 and cholesterol pathways was proximal to, or in linkage disequilibrium with, 7-dehydrocholesterol reductase DHCR7 rs1790349, endothelial lipase LIPG rs4939883 and proprotein convertase subtilisin/kexin type 9 PCSK9 rs11206510., Conclusions: The associations between cholesterol biomarkers and vitamin D metabolite levels in CIS are consistent with the biochemical inter-dependence between the two pathways. Cholesterol biomarkers should be considered for inclusion as covariates when assessing vitamin D levels in CIS., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Objectives: To investigate the associations between antibody responses to herpesviruses and the development of thalamic, total deep gray matter, cortical and central atrophy in high-risk clinically isolated syndromes (CIS) after the first demyelinating event., Methods: We analyzed volumetric brain outcomes in 193 CIS patients enrolled in a multi-center study of high-risk CIS. All patients had 2 or more MRI brain lesions and two or more oligoclonal bands in cerebrospinal fluid. Serum samples obtained at the screening visit prior to any treatment were analyzed for IgG antibodies against cytomegalovirus (anti-CMV) and Epstein-Barr virus (EBV) viral capsid antigen (VCA). All patients were treated with interferon-beta. Clinical and MRI assessments were obtained at baseline, 6, 12, and 24 months., Results: Anti-EBV VCA highest quartile status was associated with regional atrophy measures for percent decrease in thalamus. Anti-CMV positivity was associated with greater total deep gray matter atrophy and whole brain atrophy. Anti-EBV VCA highest quartile status was associated as trends with greater whole brain, gray matter atrophy and central atrophy. The associations of anti-EBV VCA antibodies with thalamic atrophy were mediated by its associations with T2 lesions whereas the associations of anti-CMV positivity with deep gray matter atrophy were relatively independent of T2 lesions., Conclusions: Antibody responses to EBV and CMV are associated with global and regional brain atrophy in CIS patients treated with interferon-beta., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Objectives: To investigate the associations of serum lipid profile with disease progression in high-risk clinically isolated syndromes (CIS) after the first demyelinating event., Methods: High density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C) and total cholesterol (TC) were obtained in pretreatment serum from 135 high risk patients with CIS (≥ 2 brain MRI lesions and ≥ 2 oligoclonal bands) enrolled in the Observational Study of Early Interferon β-1a Treatment in High Risk Subjects after CIS study (SET study), which prospectively evaluated the effect of intramuscular interferon β-1a treatment following the first demyelinating event. Thyroid stimulating hormone, free thyroxine, 25-hydroxy vitamin D3, active smoking status and body mass index were also obtained. Clinical and MRI assessments were obtained within 4 months of the initial demyelinating event and at 6, 12 and 24 months., Results: The time to first relapse and number of relapses were not associated with any of the lipid profile variables. Higher LDL-C (p=0.006) and TC (p=0.001) levels were associated with increased cumulative number of new T2 lesions over 2 years. Higher free thyroxine levels were associated with lower cumulative number of contrast-enhancing lesions (p=0.008). Higher TC was associated as a trend with lower baseline whole brain volume (p=0.020). Higher high density lipoprotein was associated with higher deseasonalised 1,25-dihydroxy vitamin D3 (p=0.003) levels and a trend was found for deseasonalised 25-hydroxy vitamin D3 (p=0.014)., Conclusions: In early multiple sclerosis, lipid profile variables particularly LDL-C and TC levels are associated with inflammatory MRI activity measures.

Objectives: To investigate whether anti-herpesvirus antibodies are associated with serum cholesterol profiles in clinically isolated syndromes (CIS)., Methods: Pre-treatment serum samples from 118 high-risk CIS patients were analyzed for IgG antibodies against cytomegalovirus (anti-CMV), Epstein Barr virus (EBV) viral capsid antigen (VCA) and EBV nuclear antigen-1 (EBNA-1). A lipid profile consisting of high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) and total cholesterol (TC) was obtained. Clinical and MRI assessments were obtained at baseline, 6, 12, and 24 months after start of interferon-beta treatment., Results: The study included 118 CIS patients (77 females, 41 males, 65.3% female; mean age: 28.1±SD 8.1 years). Anti-EBV EBNA-1 antibody levels were associated with LDL-C (p=0.009) and TC (p=0.008) levels. Anti-CMV positivity status was associated with reduced time to relapse (p=0.006) and the greater number of relapses (p=0.009) in patients with high HDL-C. Anti-EBV VCA antibody levels were associated with greater number of new T2 lesions (p=0.002) and with increased brain atrophy (p<0.001) in patients with high LDL-C., Conclusions: Our results indicate that higher levels of anti-EBV EBNA-1 antibodies are associated with higher LDL-C and TC levels. Anti-CMV positive individuals have greater disease progression in the presence of higher HDL-C levels. Individuals with higher levels of anti-EBV VCA antibodies have greater progression on MRI measures in the presence of higher LDL-C., (© 2013.)

Objectives: To investigate the associations of environmental MS risk factors with clinical and MRI measures of progression in high-risk clinically isolated syndromes (CIS) after the first demyelinating event., Methods: We analyzed 211 CIS patients (age: 28.9±7.8 years) enrolled in the SET study, a multi-center study of high-risk CIS patients. Pre-treatment samples were analyzed for IgG antibodies against cytomegalovirus (anti-CMV), Epstein Barr virus (EBV) early nuclear antigen-1 (EBNA-1), viral capsid antigen (VCA), early antigen-diffuse (EA-D), 25 hydroxy-vitamin D3 and cotinine levels and HLA DRB1*1501 status. The inclusion criteria required evaluation within 4 months of the initial demyelinating event, 2 or more brain MRI lesions and the presence of two or more oligoclonal bands in cerebrospinal fluid. All patients were treated with interferon-beta. Clinical and MRI assessments were obtained at baseline, 6, 12, and 24 months., Results: The time to first relapse decreased and the number of relapses increased with anti-CMV IgG positivity. Smoking was associated with increased number and volume of contrast-enhancing lesions (CEL) during the 2-year period. The cumulative number of CEL and T2 lesions during the 2-year period was greater for individuals in the highest quartile of anti-EBV VCA IgG antibodies. The percent loss of brain volume was increased for those in the highest quartile of with anti-EBV VCA IgG antibodies., Conclusions: Relapses in CIS patients were associated with CMV positivity whereas anti-EBV VCA positivity was associated with progression on MRI measures, including accumulation of CEL and T2 lesions and development of brain atrophy.

Objective: To examine the associations of alcohol consumption patterns with disability and brain injury in multiple sclerosis (MS) patients., Design: This study included 423 subjects (272 MS patients, 151 healthy controls) participating in a study of clinical, environmental and genetic risk factors in MS. Disability was assessed with the Expanded Disability Status Scale (EDSS) and the MS Severity Scale (MSSS). Brain injury was assessed using the quantitative MRI measures of T2-lesion volume (T2-LV), T1-LV, normalized volumes of brain parenchyma (NBV), gray matter (NGMV) and lateral ventricle (NLVV). Information related to alcohol-consumption patterns was obtained with standardized questionnaire during an in-person interview. The associations of alcohol consumption variables with disability and MRI measures were assessed in regression analyses., Results: The frequency of MS patients who did not consume alcohol after MS (19.4%) was higher than the frequency before MS (p<0.001). The EDSS, NGMV and NLVV exhibited a non-linear dependence on duration of alcohol consumption after MS onset: non-linear regression analyses indicated that EDSS and NLVV were lower and the NGMV was greater in MS patients who had consumed for a period of 15years or less after MS onset compared those who did not consume alcohol or consumed it for more than 15years., Conclusion: The duration of alcohol consumption is associated with disability and MRI measures in MS. Prospective, longitudinal studies of the role of alcohol in MS disease progression are warranted., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Background: Chronic cerebrospinal venous insufficiency (CCSVI) was described as a vascular condition characterized by anomalies of veins outside the skull was reported to be associated with multiple sclerosis (MS). The objective was to assess the associations between HLA DRB1*1501 status and the occurrence of CCSVI in MS patients., Methodology/principal Findings: This study included 423 of 499 subjects enrolled in the Combined Transcranial and Extracranial Venous Doppler Evaluation (CTEVD) study. The HLA DRB1*1501 status was obtained in 268 MS patients and 155 controls by genotyping rs3135005, a SNP associated with DRB1*1501 status. All subjects underwent a clinical examination and Doppler scan of the head and neck. The frequency of CCSVI was higher (OR = 4.52, p<0.001) in the MS group 56.0% vs. 21.9% in the controls group and also higher in the progressive MS group 69.8% vs. 49.5% in the non-progressive MS group. The 51.9% frequency of HLA DRB1*1501 positivity (HLA(+)) in MS was higher compared (OR = 2.33, p<0.001) to 31.6% to controls. The HLA(+) frequency in the non-progressive (51.6%) and progressive MS groups (52.3%) was similar. The frequency of HLA(+) CCSVI(+) was 40.7% in progressive MS, 27.5% in non-progressive MS and 8.4% in controls. The presence of CCSVI was independent of HLA DRB1*1501 status in MS patients., Conclusions/significance: The lack of strong associations of CCSVI with HLA DRB1*1501 suggests that the role of the underlying associations of CCSVI in MS should be interpreted with caution. Further longitudinal studies should determine whether interactions between these factors can contribute to disease progression in MS.

Purpose: To characterize gene expression in multiple sclerosis (MS) patients after the first dose and chronic dosing of 30 microg, once weekly, intramuscular interferon-beta1a (IFN-beta) and to delineate the pharmacogenomic differences between Good Responders and Partial Responders to IFN-beta therapy., Methods: The treatment responses after the first IFN-beta dose and chronic IFN-beta dosing were assessed in 22 relapsing MS patients (17 females, 5 males; average age: 41.5+/-SD 10.4 years). Gene expression profiles in peripheral blood mononuclear cells were obtained prior to treatment and at 1, 2, 4, 8, 24, 48, 120, 168 h after the first IFN-beta dose and at 1, 6 and 12 months after chronic dosing with once-weekly 30 microg IFN-beta-1a intramuscularly. Repeated measures statistics with false discovery rate control were used. The functional characteristics, biological pathways and transcription factor sites were analyzed., Results: Of the 1000 genes modulated following the first dose and upon chronic dosing of IFN-beta in MS patients, approximately 35% were up-regulated and 65% were down- regulated; the percentage of modulated genes in common was approximately 50%. The expression of the pharmacodynamic mRNA markers of IFN-beta effect showed differences in time profiles for the Good Responder and Partial Responders to IFN-beta therapy and the Jak-STAT, TNFRSF10B, IL6, TGFbeta, retinoic acid and CDC42 pathways were differentially modulated. The patients with side effects to therapy showed differences in the TGFbeta1, IFNG/STAT3 and TNF pathways., Conclusions: Gene expression is a valuable tool for understanding the molecular mechanisms of IFN-beta action in MS patients.

Purpose: To investigate the relationship between immune cell secretion of brain-derived neurotrophic factor (BDNF) with clinical and MRI variables in multiple sclerosis (MS) patients., Background: BDNF exerts beneficial effects on neuronal growth and repair and is secreted by both neurons and immune cells. Consequently, it may mediate the crosstalk between the immune system and CNS in autoimmune diseases such as MS., Methods: Fifty-two relapsing MS patients (41 females, age: 48.8+/-6.6 years, disease duration: 12.7+/-8.4 years) were enrolled. Clinical and MRI measurements (including, T1-, T2- and contrast-enhancing (CE) lesion volumes (LVs); normalized measures of whole brain, white matter (WM) and gray matter (GM) volumes; diffusion weighted imaging measure of mean whole brain (WB) parenchyma diffusivity and magnetization transfer ratio (MTR) measures were obtained., Results: Immune cell BDNF secretion after anti-CD3 plus anti-CD28 stimulation was positively associated with increased CE-LV (p=0.026). The MTR of CE-LV and normal-appearing (NA) WM (NAWM) were negatively associated with immune cell BDNF secretion after anti-CD3 plus anti-CD28 stimulation. Immune cell BDNF secretion after anti-CD3 plus anti-CD28 was positively associated with higher WM volume (p=0.027). Immune cell BDNF secretion after anti-CD3 plus anti-CD28 stimulation was decreased with increasing disease duration (p=0.031). The BDNF secretion was independent of the BDNF Val66Met (dBSNP ID: rs6265) SNP genotype., Conclusions: Immune cell BDNF secretion is associated with the sites of higher inflammatory activity as evidenced by CE lesions and may represent an important factor associated with the WM volume of patients with MS.

Purpose: Multiple sclerosis (MS) patients have a high risk of low bone density. The purpose of this study was to examine the molecular mechanisms potentially capable of modulating bone homeostasis in response to interferon-beta-1a (IFN-beta-1a) treatment and the focus was the bone-modulating system comprised of receptor activator of nuclear factor-kappaB (RANK), its ligand RANKL and its decoy receptor, osteoprotegerin (OPG)., Methods: In this open-label pharmacodynamic study, peripheral blood was obtained from relapsing-remitting MS patients just prior to and at multiple time points after intramuscular injection of 30 microg IFN-beta-1a. Samples were analysed for RANKL, tumour necrosis factor related apoptosis-inducing ligand (TRAIL), OPG and macrophage inflammatory protein-1 alpha/beta expression. Osteoclast precursor differentiation from peripheral blood cells of MS patients in the presence of exogenously added IFN-beta-1a was also assessed. Additionally, the changes in plasma levels of osteocalcin and the C-telopeptides after 1 year of treatment were measured as surrogate markers of bone formation and degradation, respectively., Results: IFN-beta-1a treatment modulated RANKL and OPG in a selective, time-dependent manner. The levels of OPG protein decreased 25% at the 8-h time point, then increased 43% at the 24-h time point. The levels of free RANKL reached a maximum at the 8-h time point. Increases in the levels of macrophage inflammatory protein-1beta (MIP-1beta), a chemokine that increases osteolysis, were observed. The levels of the bone formation marker, osteocalcin, were lower in MS patients compared to controls and increased after one year of treatment. Ex vivo treatment of peripheral blood lymphocytes with IFN-beta resulted in a marked reduction of osteoclast-like cells in the presence of RANKL and macrophage colony stimulating factor., Conclusions: IFN-beta treatment induces complex, specific and time-dependent changes in multiple proteins and mRNAs related to bone homeostasis in MS patients.

The objective of this study was to evaluate multiple interferon (IFN) specific mRNA biomarkers in multiple sclerosis (MS) patients with anti-IFN-beta neutralizing antibodies (NAB) using a pharmacodynamic study design. Thirty patients were enrolled. Blood samples were drawn at pre-treatment, 4-, 8-h time points following the intramuscular dose of IFN-beta-1a. Total RNA was obtained from peripheral blood cells, processed to cDNA and analyzed using quantitative real-time polymerase chain reaction. Pre-treatment serum samples were analyzed for anti-IFN-beta binding and neutralizing antibodies: 22 patients were NAB negative; equal numbers of the eight remaining patients were either NAB positive or had borderline NAB status. The results showed that early assessment (at 4 h after IFN-beta injection) of mRNAs for Stat-1, MxA, MxB and TRAIL was more sensitive than the later measurements. Furthermore, the NAB positive patients had strongly attenuated gene expression responses on all the mRNAs. Patients with borderline NAB had average responses that appear to be lower than NAB negative patients on several genes, notably Stat-1, TRAIL and beta2 microglobulin.

The purpose of this report was to characterize the dynamics of the gene expression cascades induced by an IFN-beta-1a treatment regimen in multiple sclerosis patients and to examine the molecular mechanisms potentially capable of causing heterogeneity in response to therapy. In this open-label pharmacodynamic study design, peripheral blood was obtained from eight relapsing-remitting multiple sclerosis patients just before and at 1, 2, 4, 8, 24, 48, 120, and 168 h after i.m. injection of 30 micro g of IFN-beta-1a. The total RNA was isolated from monocyte-depleted PBL and analyzed using cDNA microarrays containing probes for >4000 known genes. IFN-beta-1a treatment resulted in selective, time-dependent effects on multiple genes. The mRNAs for genes implicated in the anti-viral response, e.g., double-stranded RNA-dependent protein kinase, myxovirus resistance proteins 1 and 2, and guanylate binding proteins 1 and 2 were rapidly induced within 1-4 h of IFN-beta treatment. The mRNAs for several genes involved in IFN-beta signaling, such as IFN-alpha/beta receptor-2 and Stat1, were also increased. The mRNAs for lymphocyte activation markers, such as IFN-induced transmembrane protein 1 (9-27), IFN-induced transmembrane protein 2 (1-8D), beta(2)-microglobulin, and CD69, were also increased in a time-dependent manner. The findings demonstrate that IFN-beta treatment induces specific and time-dependent changes in multiple mRNAs in lymphocytes of multiple sclerosis patients that could provide a framework for rapid monitoring of the response to therapy.

Purpose: To investigate the effects of interferon-beta-1a (IFN-beta-1a) on the trafficking of cell populations in peripheral blood cells of multiple sclerosis (MS) patients., Methods: In this open-label pharmacodynamic study, peripheral blood was obtained from 10 relapsing-remitting (RR) MS patients just prior to and at 1, 2, 4, 8, 24, 48, 120, and 168 h after intramuscular injection of 30-microg IFN-beta-1a. Timed samples were also obtained from five controls at 0, 8, 24, 48 and 168 h. The blood cells were analyzed using four-color flow cytometry with antibody conjugates directed against cell surface proteins specific for T cells, B cells, NK cells, and the activation marker, CD69., Results: IFN-beta-1a treatment resulted in selective, time-dependent effects on many cell populations in peripheral blood. The trafficking of T-helper and T-suppressor/cytotoxic subsets of T cells were qualitatively different. The most prominent effects were on the trafficking of natural killer cells, the levels of which decreased to 23.5% of pretreatment values at 8 h after treatment. The levels of CD69-positive NK cells increased to a peak value of 606% of pretreatment levels at the 24-h time point. In untreated controls, these characteristic trafficking effects were not observed. There was inter-patient heterogeneity in the levels of activated NK cells at the 6-month time point that may potentially be relevant for individualizing IFN-beta therapy., Conclusions: IFN-beta treatment can induce specific, selective, and time-dependent trafficking of cells and its effects on different subsets of a given cell type are not qualitatively similar. The dynamics indicate that the activation of NK cells by IFN-beta is possibly dependent on the trafficking of NK cells. The activated NK cell levels after prolonged therapy may potentially provide a surrogate marker for IFN-beta exposure.

Real-time compression ultrasound (CU) along with venous duplex imaging is the most commonly performed noninvasive vascular examination. It has become the definitive diagnostic test for most patients with deep venous thrombosis (DVT). Some practioners have recommended that CU alone of the common femoral vein (CFV) and of the popliteal vein (PV) are all that is required since a complete examination is time consuming and calf veins are difficult to visualize. However, if only the CFV and PV are examined, all patients with isolated superficial femoral vein (SFV) and calf DVT remain undiagnosed. The purpose of this study is to establish the value of a comprehensive venous duplex examination compared to CFV and PV compression alone for detecting both proximal and infrapopliteal DVT. From January 1996 through December 1997, the initial venous duplex examinations of 5767 extremities in 3067 patients were reviewed and results tabulated according to presence and location of clot. The ATL 3000 with a 7-14 mHz probe was utilized. Studies were interpreted as normal, proximal DVT (popliteal and above, with or without calf DVT), isolated calf, or isolated SFV deep venous thrombosis. If only the CFV and PV had been examined, 30.3% (isolated SFV + isolated calf vein DVT) of all DVT and 4.5% of proximal DVT would have been missed. A complete venous duplex examination altered the care in 288 (30.3%) of all patients examined who had DVT, and is therefore recommended as the standard noninvasive examination when evaluating patients for acute DVT.

The ability of cholesterol to move between bovine rod outer segment disk membranes and phospholipid membranes was examined. Disk membranes were incubated with small unilamellar phospholipid vesicles containing varying amounts of cholesterol. Aliquots were removed at specific times, and then the disks and the vesicles were separated by centrifugation and assayed for phospholipid and cholesterol content. When incubated with vesicles containing no cholesterol, the cholesterol to phospholipid ratio in the disk membrane was reduced due to migration of cholesterol from the disks into the vesicles. The cholesterol content of these cholesterol depleted disks could be readily returned to the normal disk cholesterol content by incubation of the cholesterol-depleted disks with small unilamellar vesicles containing high cholesterol. An apparent partition coefficient K was calculated as the quotient of the cholesterol/phospholipid mole ratio in the donor membranes and the cholesterol/phospholipid mole ratio in the acceptor membranes. The value of K was approximately 1 at cholesterol levels below normal disk cholesterol content, for disk membranes and phosphatidylcholine small unilamellar vesicles. Inclusion of phosphatidylethanolamine in the small unilamellar vesicle acceptor raised K, indicating that phosphatidylethanolamine creates an unfavourable environment for cholesterol. The cholesterol to phospholipid ratio of native disks could be increased by incubation with phosphatidylcholine small unilamellar vesicles (donor) which contained higher amounts of cholesterol than the disk membrane acceptor. In these experiments the distribution of cholesterol between disks and small unilamellar vesicles always favored the vesicles. The apparent partition coefficient was 1.7 at several cholesterol levels above the native disk cholesterol content. Liposomes made from lipid extracted from the disk membrane behaved in the same manner as intact disks with respect to cholesterol distribution at equilibrium. The phospholipid content of the disk membrane may be an important factor in determining the cholesterol content of the disk membrane.