Peripheral Blood Mononuclear Cells Membrane Research Articles

Virus-inhibitory activity of the antigen complex of opportunistic pathogenic bacteria against SARS-CoV-2

Introduction. The antigen complex of opportunistic pathogenic bacteria (ACOPB) has a protective effect against avian influenza viruses, herpes virus type 2, and other viruses that cause acute respiratory viral infections. In the context of the COVID-19 pandemic, an important task is to find out whether ACOPB has a protective effect against SARS-CoV-2.
 The purpose of the study was to evaluate in vitro the ACOPB virus-inhibitory activity against the Dubrovka laboratory strain of SARS-CoV-2.
 Materials and methods. The study was performed using Vero cell line CCL-81, human peripheral blood mononuclear cells (PBMCs), mouse monoclonal anti-idiotypic antibodies structurally mimicking biological effects of human interferons (IFNs), the Dubrovka laboratory strain of SARS-CoV-2. The infectivity of the virus was assessed by two methods: by virus titration using cell cultures and the limiting dilution method when the results are assessed by a cytopathic effect; the second method was a plaque assay. The in vitro virus inhibition test was performed using the cell culture susceptible to SARS-CoV-2; the mixture containing a specific dose of the virus and a two-fold dilution of ACOPB was transferred to the cell culture after the ACOPB medication had interacted with the virus at 4C for 2 hours. The ACOPB virus-inhibitory activity against SARS-CoV-2 was assessed by the functional activity of / and IFN receptors (RIFN) in human PBMCs induced in vitro by ACOPB and the ACOPB mixture with the specific dose of SARS-CoV-2. The RIFN expression level was measured by the indirect membrane immunofluorescence test.
 Results. Hemagglutination assay using chicken, mouse, guinea pig, and human red blood cells was performed for detection of the SARS-CoV-2 inhibitory protein. The lysate of Vero CCL-81 cells infected with SARS-CoV-2 Dubrovka demonstrated the highest hemagglutination activity with guinea pig red blood cells and low titers of hemagglutination in the virus-containing fluid. The virus inhibition test in the Vero CCL-81 cell culture demonstrated that ACOPB inhibited 10 doses of SARS-CoV-2 Dubrovka with the titer 1 : 32, providing 100% protection of the cell culture for 8 days (the monitoring period). ACOPB induced / and RIFN expression on membranes of human PBMCs in in vitro cultures and decreased RIFN / and expression after its interaction with SARS-CoV-2 Dubrovka.
 Conclusion. The experimental studies including the virus inhibition test in the cell culture susceptible to SARS-CoV-2 Dubrovka and the indirect membrane immunofluorescence assay using monoclonal anti-idiotypic antibodies mimicking IFN-like properties demonstrated that ACOPB had both an immunomodulatory and a virus-inhibitory effect.

Biological properties of domestic strain vRub-Ant of rubella virus

Introduction. Rubella is a mild infectious disease affecting mainly children and is caused by the rubella virus, part of the Matonoviridae family, genus Rubivirus. Rubella causes congenital rubella syndrome (CRS) and is the main cause of developmental abnormalities, especially blindness and deafness.
 There is no specific treatment for rubella and CRS. In order to avoid possible complications from rubella infection, a live attenuated rubella vaccine based on the foreign strain of Wistar RA 27/3 rubella virus is used. However, the actual, more effective and preferred vaccine strain the rubella virus for the Russian Federation is considered to be a viral strain of rubella circulating on its territory.
 The aim of the study was to study the biological properties of the developed domestic cold-adapted strain vRub-Ant circulating in the territory of the Russian Federation.
 Materials and methods. Following cell cultures were used in the study human embryo lung diploid cell strain LECH-3, transferable cell line from embryonic kidney cells of green monkeys Vero CCL-81 and Vero ECC, human mesenchymal stem cells, human peripheral blood mononuclear cells (PBMC). Cell cultures were grown on a DMEM/F12 nutrient medium with the addition of 5% fetal bovine serum. Swabs from the pharynx and nasal passages from a child with rubella were used as clinical virus-containing material. Monoclonal anti-idiotypic antibodies m(anti-ID)Ab were used to assess the expression level of alpha/beta and gamma interferon receptors (/ and IFN-R)Ab, imitating the biological effects of alpha/beta and gamma interferons (/ and IFN) of humans. The cultural, virological, immunochemical and serological research methods were applied in the study.
 Results. Attenuation of the vRub-Ant clinical isolate of rubella virus was carried out for 20 consecutive passages on LECH-3 diploid cells at a reduced temperature of 30C. The main biological markers of attenuation were determined to be ts and ca phenotypes. The avirulence of the attenuated viral strain (att-phenotype) was assessed by the level of expression of / and IFN-R. A lower level of / and IFN-R expression was found on the membranes of human PBMC induced by the vaccine strain vRub-Ant in comparison with the parent wild variant of the rubella virus. This trait,the att phenotype, is characteristic of attenuated viral strains. It has been shown that the vaccine strain vRub-Ant has lost neurotropism and was unable to bind to the membrane receptors of the brain (MRB) of guinea pig embryos, unlike its parent rubella virus strain. The high immunogenicity of the domestic cold-adapted strain vRub-Ant was confirmed by high titers of neutralizing rubella antibodies observed in guinea pigs immunized subcutaneously with one vaccination dose of the virus.
 Conclusion. A domestic attenuated vaccine strain vRub-Ant of the rubella virus that has the main biological markers of attenuation (ts-ca and att phenotypes) has been developed. The vaccine strain vRub-Ant induces a high levels of neutralizing antibodies in guinea pigs following the immunization with a single vaccination dose of the vaccine. The viral strain vRub-Ant has lost its tropism to the MRB of guinea pig embryos, unlike its parent variant.

Drug transporters expression on PBMC membrane is associated with tacrolimus intracellular concentration

Measuring tacrolimus (TAC) its whole blood concentrations (Cmin) is mandatory in liver and kidney transplant recipients (LTR and KTR). However, while having adequate Cmin, some patients still experience rejection/adverse events, highlighting the limitation of the actual monitoring. As TAC exerts its effect inside T cells, monitoring intracellular instead of whole blood concentrations is an appealing strategy. Some drug transporters expressed at the cells membrane could be major factors of TAC diffusion into peripheral blood mononuclear cells (PBMC). The aim of the study was to explore the relationship between TAC diffusion into PBMC and cell membrane expression of four drug transporters (P-glycoprotein (P-gp), Multidrug resistance-associated protein 2 (MRP-2), Concentrative nucleoside transporter 3 (CNT-3) and Equilibrative nucleoside transporter 1(ENT-1)). Sixty stable LTR and KTR were included in the study. TAC Blood and PBMC concentrations were determined by liquid chromatography coupled with tandem mass spectrometry. P-gp, MRP-2, CNT-3 and ENT-1 expression at the PBMC surface was evaluated using flux cytometry. Correlation between TAC PBMC/blood ratios and transporters expressions were explored using correlation tests. TAC PBMC/blood ratios were not different between LTR and KTR and the results were then analyzed altogether. P-gp, CNT-3 and ENT-1 expressions show positive correlation with TAC PBMC/blood ratio. Correlation was stronger for ENT-1 (R2 = 0.31, p < 0.0001) than for P-gp and CNT-3 (R2 = 0.17, p = 0.001 and R2 = 0.14, p = 0.003, respectively). MRP-2 expression was not correlated with PBMC/blood ratio ( Fig. 1 ). In this study, TAC diffusion into PBMC increased as a function of membrane expression of ENT-1, CNT-3 and P-gp. ENT-1 expression seems to be the strongest driver of TAC diffusion, which is consistent with its role as an influx transporter. Findings for P-gp might be explained by an induction of its expression when intracellular TAC concentration increases. ENT-1 and CNT-3 influx effects on TAC diffusion would then outweigh the P-gp efflux effect.

Evaluation of apoptotic potential of glyphosate metabolites and impurities in human peripheral blood mononuclear cells (in vitro study)

Glyphosate is used for cereal, vegetable and fruit crops for reducing or inhibiting the growth of weeds as well as a desiccant for various grain crops. That is why, glyphosate has been shown to be accumulated in humans and animals through ingestion of food of both plant and animal origin.The study aimed to assessed the effect of glyphosate, its metabolites: aminomethylphosphonic acid (AMPA), methylphosphonic acid and its impurities: PMIDA, N-methylglyphosate, hydroxymethylphosphonic acid and bis(phosphonomethyl)amine on apoptosis induction in human peripheral blood mononuclear cells (PBMCs). PBMCs were exposed to the compounds studied at the concentrations ranging from 0.01 to 5 mM for 4 h.We have observed an increase in reactive oxygen species (including hydroxyl radical) and cytosolic calcium ions levels as well as reduction of transmembrane mitochondrial potential (ΔΨm) in PBMCs exposed to the compounds examined. All substances studied changed PBMCs membrane permeability, activated caspase-8, -9, -3 and caused chromatin condensation, which showed that they were capable of inducing apoptosis both via extrinsic and particularly intrinsic pathway.Generally the study demonstrated that there were no differences between apoptotic changes induced by glyphosate, its metabolites or impurities, and observed changes were provoked by high concentrations of investigated compounds.

CD77 levels over enzyme replacement treatment in Fabry Disease Family (V269M).

ABSTRACTIntroduction:Fabry disease (FD) is a disorder caused by mutations in the gene encoding for lysosomal enzyme α-galactosidase A (α-GAL). Reduced α-GAL activity leads to progressive accumulation of globotriaosylceramide (Gb3), also known as CD77. The recent report of increased expression of CD77 in blood cells of patients with FD indicated that this molecule can be used as a potential marker for monitoring enzyme replacement therapy (ERT).Objective:The purpose of this study was to evaluate the CD77 levels throughout ERT in FD patients (V269M mutation).Methods:We evaluated the fluctuations in PBMC (peripheral blood mononuclear cell) membrane CD77 expression in FD patients undergoing ERT and correlated these levels with those observed in different cell types.Results:A greater CD77 expression was found in phagocytes of patients compared to controls at baseline. Interestingly, the variability in CD77 levels is larger in patients at baseline (340 - 1619 MIF) and after 12 months of ERT (240 - 530 MIF) compared with the control group (131 - 331 MFI). Furthermore, by analyzing the levels of CD77 in phagocytes from patients throughout ERT, we found a constant decrease in CD77 levels.Conclusion:The increased CD77 levels in the phagocytes of Fabry carriers together with the decrease in CD77 levels throughout ERT suggest that measuring CD77 levels in phagocytes is a promising tool for monitoring the response to ERT in FD.

Changes of the peripheral blood mononuclear cells membrane fluidity from type 1 Gaucher disease patients: an electron paramagnetic resonance study.

Gaucher disease (GD) is a lysosomal storage disorder, caused by an impaired function of β-glucocerebrosidase, which results in accumulation of glucocerebroside in cells, and altered membrane ordering. Using electron paramagnetic resonance spin labeling, a statistically significant difference in the order parameter between the peripheral blood mononuclear cell membranes of GD patients and healthy controls was observed. Moreover, the results show that the introduction of the enzyme replacement therapy leads to the restoration of the physiological membrane fluidity. Accordingly, this simple method could serve as a preliminary test for GD diagnosis and therapy efficiency.

Antiviral Lipopeptide-Cell Membrane Interaction Is Influenced by PEG Linker Length.

A set of lipopeptides was recently reported for their broad-spectrum antiviral activity against viruses belonging to the Paramyxoviridae family, including human parainfluenza virus type 3 and Nipah virus. Among them, the peptide with a 24-unit PEG linker connecting it to a cholesterol moiety (VG-PEG24-Chol) was found to be the best membrane fusion inhibitory peptide. Here, we evaluated the interaction of the same set of peptides with biomembrane model systems and isolated human peripheral blood mononuclear cells (PBMC). VG-PEG24-Chol showed the highest insertion rate and it was among the peptides that induced a larger change on the surface pressure of cholesterol rich membranes. This peptide also displayed a high affinity towards PBMC membranes. These data provide new information about the dynamics of peptide-membrane interactions of a specific group of antiviral peptides, known for their potential as multipotent paramyxovirus antivirals.

Bisphenol A and its analogs exhibit different apoptotic potential in peripheral blood mononuclear cells (in vitro study)

There are only a few studies that have assessed the effect of bisphenol A (BPA) on human blood cells and no study has been conducted to analyze the impact of BPA analogs on human leucocytes. In this study, we have investigated the effect of BPA and its analogs like bisphenol F (BPF), bisphenol S (BPS) and bisphenol AF (BPAF) on apoptosis induction in human peripheral blood mononuclear cells (PBMCs). In order to clarify the mechanism of bisphenols-induced programmed cell death, changes in various signaling molecules of this process have been assessed. We observed an increase in cytosolic calcium ions (Ca2+) level and reduction of transmembrane mitochondrial potential (ΔΨm) in PBMCs incubated with all compounds examined, and particularly BPA and BPAF. All compounds studied changed PBMCs membrane permeability, activated caspase-8, -9, -3 and induced PARP-1 cleavage and chromatin condensation, which confirmed that they were capable of inducing apoptosis both via intrinsic and extrinsic pathway. Moreover, we have found that modus operandi of bisphenols studied was different. We noticed that BPAF and BPS caused mainly necrotic and apoptotic changes, respectively, whereas BPA induced comparable apoptotic and necrotic effects in the incubated cells.

N–3 Long-chain PUFAs reduce respiratory morbidity caused by iron supplementation in iron-deficient South African schoolchildren: a randomized, double-blind, placebo-controlled intervention

Although iron supplementation in malaria-free areas mostly reduces infectious morbidity, it can sometimes increase morbidity from infections as a result of the dependence of pathogenic microorganisms on iron. Supplementation with n-3 (ω-3) long-chain polyunsaturated fatty acids (LCPUFAs) improved morbidity in several human studies. However, information on the combined effect of iron and n-3 LCPUFA supplementation on infectious morbidity is limited. We determined whether n-3 LCPUFAs and iron supplementation, alone or in combination, affected absenteeism and illness in iron-deficient schoolchildren with low fish intake. A total of 321 South African children (aged 6-11 y) with iron deficiency (ID) were randomly divided into 4 groups to receive 1) iron plus placebo, 2) a mixture of docosahexaenoic acid and eicosapentaenoic acid (DHA/EPA) plus placebo, 3) iron plus DHA/EPA, or 4) placebo plus placebo as oral supplements 4 times/wk for 8.5 mo. Morbidity was recorded, and iron-status indexes were measured. The total phospholipid fatty acid composition of peripheral blood mononuclear cell membranes was analyzed in a subsample (n = 130). Iron supplementation increased the number of days with illness when all symptoms were considered (B: 0.87; 95% CI: 0.71, 1.03) as well as illness that was specifically caused by respiratory symptoms (B: 1.45; 95% CI: 1.21, 1.70), whereas DHA/EPA reduced the number of days with illness at school (B: -0.96; 95% CI: -1.33, -0.59). The increases caused by iron were reduced to the levels seen in the placebo plus placebo group when iron was provided in combination with DHA/EPA as indicated by significant iron × DHA/EPA interactions (both P < 0.001). Iron supplementation increased morbidity (mostly respiratory) in iron-deficient South African schoolchildren with low DHA/EPA intake, but when iron was given in combination with DHA/EPA, this effect was prevented.

Quantitative alterations of phospholipids in peripheral blood mononuclear cells in patients with breast and cervical cancer

The aim of this study was to investigate the quantitative changes of absolute and relative amounts of diverse phospholipids in peripheral blood mononuclear cells (PBMCs) in healthy volunteers and patients with breast(BC) and cervical cancer(CC). For this purpose, PLs were analyzed using a lipidomic approach. In brief, PLs were extracted using Bligh and Dyer method, followed by a separation of PL classes by thin layer chromatography, lipid quantification was done using phosphorus assay. In thin-layer chromatography eight fractions of PLs were obtained: lysophosphatidylcholine (LPC), sphingomyelin (SPM), phosphatidylcholine (PC), phosphatidylinositol (PI), phosphatidylserine (PS), phosphatidylethanolamine (PE), phosphatidic acid (PA), diphosphatidylglycerol (DPG). Our results reveal that the all the eight PLs quantified in this study were altered in cancer patient compared to healthy individuals. It is important that the LPC, PC, PE, levels in PBMC membrane of patients with cancer were 2.4, 1.4, 1.3 times higher than those of PBMC membrane of healthy individuals. The PI, PS, PA levels in 1.1, 2.3, 1.3 times lower compared to control group. These quantitative changes in PL components indicate a possible inhibition of signaling pathways in cancer. Notably, these results were identical with those observed chronic lymphoid leukemia studied earlier. Therefore we conclude that quantitative alterations of PLs have been associated to disease and specific PLs may be involved in the onset and evolution of cancer. These data will be useful as a starting point to define possible PLs as prospective biomarkers as well as for discovery of new personalized modes for disease treatment.

In vitro effects of prolonged exposure to quercetin and epigallocatechin gallate of the peripheral blood mononuclear cell membrane.

The study aimed to assess biophysical changes that take place in the peripheral blood mononuclear cell (PBMC) membranes when exposed in vitro to 10 μM quercetin or epigallocatechin gallate (EGCG) for 24 and 48 h. PBMCs isolated from hypercholesterolemia patients were compared to those from normocholesterolemia subjects. The membrane fluidity and transmembrane potential were evaluated and the results were correlated with biochemical parameters relevant to oxidative stress, assessed in the patients’ plasma. The baseline value of PBMC membrane anisotropy for the hypercholesterolemia patients was lower than that of the control group. These results correlated with the plasma levels of advanced glycation end products, which were significantly higher in the hypercholesterolemia group, and the total plasma antioxidant status, which was significantly higher in normocholesterolemia subjects. In the case of normocholesterolemia cells in vitro, polyphenols induced a decrease in membrane anisotropy (7.25–11.88% at 24 h, 1.82–2.26% at 48 h) and a hyperpolarizing effect (8.30–8.90% at 24 h and 4.58–13.00% at 48 h). The same effect was induced in hypercholesterolemia cells, but only after 48 h exposure to the polyphenols: the decrease in membrane anisotropy was 5.70% for quercetin and 2.33% for EGCG. After 48 h of in vitro incubation with the polyphenols, PBMCs isolated from hypercholesterolemia patients exhibited the effects that had been registered in cells from normocholesterolemia subjects after 24 h exposure. These results outlined the beneficial action of the studied polyphenols, quercetin and EGCG, as dietary supplements in normocholesterolemia and hypercholesterolemia patients.

Phospholipase A2, prostaglandin E2 and polyunsaturated fatty acid metabolic abnormalities in multiple sclerosis

AbstractAimMetabolic abnormalities reported in patients with multiple sclerosis include a decrease in cell membrane fatty acid C20:4n‐6. The aim of the present study was to investigate whether this decrease was associated with abnormalities in the prostaglandin E2 pathway in patients with multiple sclerosis.MethodsThe study population included 31 patients with multiple sclerosis and 30 healthy controls. Peripheral blood mononuclear cell membrane fatty acids were measured by gas chromatography, secretory‐phospholipase A2, and prostaglandin E2 with enzyme‐linked immunosorbent assays and C‐reactive protein with a Beckman auto‐analyser.ResultsProstaglandin E2 was increased in patients (545.5 pg/mL; quartile range 585.1 pg/mL) and controls (248.2 pg/mL; quartile range 183.6 pg/mL; P = 0.0018). Phospholipase A2 was inversely associated with C20:4n‐6 in patients and controls, respectively (P = 0.0398 and P = 0.0182). C‐reactive protein showed a positive association with phospholipase A2 in patients (P = 0.0006), and an inverse association with prostaglandin E2 in controls (P = 0.0006).ConclusionsThe increase in prostaglandin E2 concentration in plasma from patients with multiple sclerosis was possibly enhanced by the positive association between the C‐reactive protein and phospholipase A2 concentrations present in patients; that is, active stimulation of the prostaglandin E2 pathway, which can possibly explain decreases in membrane n‐6 fatty acid C20:4n‐6 reported in cell membranes from patients. It is not clear from the results of the present study whether this denotes chronic inflammation in patients, but could be expected to contribute to central nervous system damage reported in patients with multiple sclerosis.

Anti-citrullinated Protein Antibodies Activated ERK1/2 and JNK Mitogen-activated Protein Kinases via Binding to Surface-expressed Citrullinated GRP78 on Mononuclear Cells

In a previous study, we found that anti-citrullinated protein antibodies (ACPAs) enhance nuclear factor (NF)-κB activity and tumor necrosis factor (TNF)-α production by normal human peripheral blood mononuclear cells (PBMCs) and U937 cells via binding to surface-expressed citrullinated glucose-regulated protein 78 (cit-GRP78). However, the downstream signaling pathways remain unclear after binding. In the present study, we firstly measured the effects of different kinase inhibitors on ACPA-mediated TNF-α production from normal PBMCs and monocytes. Then, the native and phosphorylated mitogen-activated protein kinases (MAPKs) were detected in ACPA-activated U937 cells by Western blotting. We also explored the role of the phosphoinositide 3-kinase (PI3K)-Akt pathway in activating IκB kinase alpha (IKK-α) in ACPA-stimulated U937 cells. Finally, we measured the amount of cit-GRP78 from PBMC membrane extracts in RA patients and controls. We found that MAPK and Akt inhibitors, but not PI3K inhibitor, remarkably suppressed ACPA-mediated TNF-α production. Interestingly, ACPAs selectively activated extracellular signal-regulated kinase 1/2 (ERK1/2) and c-jun N-terminal kinase (JNK), but not p38 MAPK, in U937 cells. This activation was suppressed by cit-GRP78, but not GRP78. The JNK activation further enhanced the phosphorylation of Akt and IKK-α. The expression of cit-GRP78 on cell membrane was higher in RA than normal PBMCs. Taken together; these results suggest that through binding to surface, over-expressed cit-GRP78 on RA PBMCs, ACPAs selectively activate ERK1/2 and JNK signaling pathways to enhance IKK-α phosphorylation, which leads to the activation of NF-κB and the production of TNF-α .

Marginal Vitamin B-6 Deficiency Decreases Plasma (n-3) and (n-6) PUFA Concentrations in Healthy Men and Women1–3

Previous animal studies showed that severe vitamin B-6 deficiency altered fatty acid profiles of tissue lipids, often with an increase of linoleic acid and a decrease of arachidonic acid. However, little is known about the extent to which vitamin B-6 deficiency affects human fatty acid profiles. The aim of this study was to determine the effects of marginal vitamin B-6 deficiency on fatty acid profiles in plasma, erythrocytes, and peripheral blood mononuclear cells (PBMC) of healthy adults fed a 28-d, low-vitamin B-6 diet. Healthy participants (n = 23) received a 2-d, controlled, vitamin B-6–adequate diet followed by a 28-d, vitamin B-6–restricted diet to induce a marginal deficiency. Plasma HDL and LDL cholesterol concentrations, FFA concentrations, and erythrocyte and PBMC membrane fatty acid compositions did not significantly change from baseline after the 28-d restriction. Plasma total arachidonic acid, EPA, and DHA concentrations decreased from (mean ± SD) 548 ± 96 to 490 ± 94 μmol/L, 37 ± 13 to 32 ± 13 μmol/L, and 121 ± 28 to 109 ± 28 μmol/L [positive false discovery rate (pFDR) adjustedP < 0.05], respectively. The total (n-6):(n-3) PUFA ratio in plasma exhibited a minor increase from 15.4 ± 2.8 to 16.6 ± 3.1 (pFDR adjustedP < 0.05). These data indicate that short-term vitamin B-6 restriction decreases plasma (n-3) and (n-6) PUFA concentrations and tends to increase the plasma (n-6):(n-3) PUFA ratio. Such changes in blood lipids may be associated with the elevated risk of cardiovascular disease in vitamin B-6 insufficiency.

Quercetin and Epigallocatechin Gallate Induce in Vitro a Dose-Dependent Stiffening and Hyperpolarizing Effect on the Cell Membrane of Human Mononuclear Blood Cells

The bioactivity of polyphenols is closely linked to their ability to interact with biological membranes. The study evaluates the in vitro effect of quercetin and epigallocatechin on the membrane anisotropy and transmembrane potential of peripheral blood mononuclear cells (PBMCs) isolated from 26 type 2 diabetes mellitus patients compared to 25 age matched controls. The in vitro assays were analyzed in correlation with the biochemical and inflammatory profile of the subjects and with insulin resistance parameters (HOMA-IR, plasma resistin) as well. For type 2 diabetes patients, the increase of HOMA-IR and resistin concentration was associated with a significant decrease of the PBMCs membrane anisotropy. The two tested polyphenols induced a dose-dependent hyperpolarizing effect and stiffening of the cell membranes for all tested subjects. Physiological levels of quercetin and epigallocatechin gallate had the tendency to normalize the PBMCs membrane anisotropy of the cells isolated from diabetes patients, bringing it to the level of cells isolated from normoglycemic ones. Epigallocatechin gallate induced higher effects compared to quercetin on the membranes isolated from subjects with higher cardiovascular risk. The decrease of membrane fluidity and the hyperpolarizing effect could explain the cardiovascular protective action of the tested compounds.

Non‐esterified fatty acids in blood cell membranes from patients with multiple sclerosis

The literature on non-esterified fatty acid (NEFA) concentrations in blood cell membranes from patients with multiple sclerosis (MS) is scarce and reports on concentrations in brain tissue from these patients are inconsistent. NEFAs are needed for several biological functions, for example, as precursors for inflammatory eicosanoid synthesis. The objective of this study was therefore to compare NEFA concentrations in blood cell membranes from patients with that of healthy control subjects, and to correlate possible changes with disease outcome. NEFA C18:2n-6 (9,12-octadecadienoic acid) was decreased in peripheral blood mononuclear cell membranes from patients, median (quartile range): patients: 0.05 (0.02) and controls: 0.07 (0.14) µg/mg protein, p = 0.007. C18:2n-6 also showed a weaker relationship with other fatty acids: with C16:0: patients: R = 0.40, p = 0.04; controls: R = 0.82, p = 0.000001. Saturated and MUFA showed positive correlations with the Bowel and bladder Functional System Scores (FSS). In contrast, in red blood cell membranes C18:2n-6 and C22:0 (docosanoic acid) showed inverse correlations with the Sensory and Brainstem FSS. The decrease in NEFA C18:2n-6 resulted in metabolic abnormalities between itself and saturated and monounsaturated NEFAs. Altered fatty acid composition in immune cell membranes would influence immune cell functions, and could possibly have contributed to the positive correlations between these fatty acids and disease outcome. Practical applications: Multiple sclerosis (MS) is a disease which presents with inflammation of the central nervous system. The cause of the disease is unknown and treatments such as anti-inflammatory, immunosuppressive medications, and fatty acids supplements are for the alleviation of symptoms only. The results from this study however, showed an altered relationship between polyunsaturated and saturated as well as monounsaturated non-esterified fatty acids in immune cells, which could have contributed to the inflammatory/infectious condition in these patients. The results from this study and further studies could possibly result in formulation of fatty acid supplements at correct doses or ratios for MS patients.

Peripheral Blood Mononuclear Cell Membrane Fluidity and Disease Outcome in Patients with Multiple Sclerosis

Immune cell membrane lipids are important determinants of membrane fluidity, eicosanoid production and phagocytosis and fatty acid metabolic abnormalities have been reported in immune cells from patients with multiple sclerosis. The aim of this study was to investigate the relationship between peripheral blood mononuclear cell membrane fluidity, permeability status, and disease outcome as measured by the Kurtzke expanded disability status scale. Phospholipids, fatty acids and cholesterol composition in peripheral blood mononuclear cells from 26 patients diagnosed with multiple sclerosis and 25 healthy control subjects were determined by colorimetric assay, gas chromatography and enzymatic assays, respectively. Membrane fluidity was calculated according to previously established formulae and correlated with C-reactive protein and the Kurtzke expanded disability status scale. There were no significant differences in membrane lipids in peripheral blood mononuclear cells from patients and controls. However, correlation studies showed lipid metabolic abnormalities, which were reflected in significant correlations between membrane fluidity as measured by both its fatty acid and phospholipid compositions, and the functional system scores. C-reactive protein showed positive correlations with phosphatidylcholine, phosphatidylserine, phosphatidylinositol and total phospholipids in membranes from control subjects. Metabolic abnormalities, as well as correlations between membrane fluidity and the functional system scores, suggested the involvement of these immune cell membranes in the disease progression. Furthermore, the changed relationship between membrane phospholipids and C-reactive protein, which has been shown to correlate with infectious episodes and clinical relapse, could be an indication of immune cell dysfunction in patients with multiple sclerosis.

Long-term effects of low doses of ionising radiation on Chernobyl clean-up workers from Latvia

Around 6000 inhabitants (20-49 years old in 1986) of Latvia took part in clean-up work in Chernobyl from 1986 till 1991. Most of them were officially documented as recipients of ionising radiation exposure (1-50 cGy). ABM (a 3-aminobenzanthrone derivative developed at the Riga Technical University, Riga, Latvia) has been previously shown to be a potential probe for determining the immune state of patients with different pathologies. The first study (using ABM) of Peripheral Blood Mononuclear Cell (PBMC) membranes of Chernobyl clean-up workers (n-97) from Latvia was conducted in 1996-1997. In 2006-2007 we examined the same (n = 54) individuals. Lipid peroxidation, ABM and ANS spectral parameters in PBMC suspension, fluorescence anisotropy and blood plasma albumin characteristics were recorded. In 1997 screening showed five different patterns of fluorescence spectra, but in 2007 we obtained only four. These patterns of spectra had never been seen previously in healthy individuals or patients with tuberculosis, multiple sclerosis, rheumatoid arthritis, etc., examined by us. The patterns of ABM fluorescence spectra were associated with membrane anisotropy and conformational changes of blood plasma albumin. It is necessary to note that all investigated parameters significantly differed in the observed groups of patients. These findings reinforce our understanding that the cell membrane is a significant biological target of radiation. These studies reveals a progressive trend towards certain resemblances to PBMC membranes of chronic B-cell lymphoid leukaemia and protein coformational alterations.

Membrane saturated fatty acids and disease progression in Multiple Sclerosis patients

The risk of developing multiple sclerosis is associated with increased dietary intake of saturated fatty acids. We determined the fatty acid composition within the different phospholipid fractions of red blood and peripheral blood mononuclear cell membranes of 31 patients diagnosed with multiple sclerosis and 30 healthy control subjects using gas chromatography. Individual saturated fatty acids were correlated with the severity of neurological outcome as measured by the Kurtzke Expanded Disability Status Scale. Significant increases were found in multiple sclerosis peripheral blood mononuclear cell membrane sphingomyelin C14:0 and phosphatidylinositol C22:0. In the peripheral blood mononuclear cell membranes, C22:0 and C24:0 showed positive correlations, while C14:0, C16:0 and C20:0 showed inverse correlations with the Functional System Scores. In conclusion, this study is in accordance with previous studies that have shown an increase in shorter long-chain SATS in MS patients. In addition, this study also showed that higher C14:0 and C16:0 reflected better disease outcome as demonstrated by the inverse correlation with the EDSS and FSS. We have also characterized the specific SATS, that is, long-chain SATS that may increase the risk of developing MS.

Redox status parameters and PBMC membrane fluidity in diabetes mellitus

The present study aims at finding correlations between certain biochemical and biophysical blood parameters for diabetes patients, focusing on the antioxidant status of the red blood cells and the membrane fluidity of peripheral blood mononuclear cells (PBMC), the endothelial function and the risk of stable interaction between the leucocytes and the endothelium. For that purpose we evaluated blood samples from 32 diabetes patients compared to a control group of 10 subjects for erythrocytes’ enzymatic activity of glucose-6-phosphate dehydrogenase and of superoxide dismutase, their susceptibility to lipid peroxidation, the plasma nitric oxide stable end products level and the PBMC membrane fluidity. Our results showed that the erythrocytes’ antioxidant mechanisms and the PBMC membrane fluidity are impaired under chronic hyperglycemic conditions. Since microvascular complications of diabetes are mainly determined by redox mechanisms, the evaluation of these parameters might help in characterizing the risk of vascular complication for diabetes patients.