Leukocytes Of Healthy Individuals Research Articles

Анализ уровня метилирования гена MIR21 в сосудах и лейкоцитах крови при атеросклерозе сонных артерий методом таргетного бисульфитного секвенирования

Методом таргетного бисульфитного секвенирования проанализирован уровень метилирования предполагаемого промоторного региона, CpG-островка и «тела» гена MIR21 в сосудах и лейкоцитах крови у пациентов с атеросклерозом сонных артерий, а также в лейкоцитах крови здоровых индивидов. Выявлено гипометилирование CpG-сайтов в гене MIR21 в сосудах по сравнению с лейкоцитами (вне зависимости от наличия заболевания). В атеросклеротической бляшке 4 последовательных CpG-сайта «тела» гена MIR21 оказались значимо гипометилированы относительно предлежащей макроскопически интактной части сонной артерии. Таким образом, установлена тканеспецифичность метилирования CpG-сайтов в гене MIR21 в сосудах, а также его связь с атеросклерозом сонных артерий. We analyzed the DNA methylation level of MIR21 gene (proposed promoter, CpG island and gene body) by targeted bisulfite sequencing in blood vessels and leukocytes of patients with carotid artery atherosclerosis and in blood leukocytes of healthy individuals. We detected DNA hypomethylation at the CpG sites in the MIR21 gene in the blood vessels compared to the leukocytes (regardless of the disease). At the same time, 4 consecutive CpG sites of the MIR21 gene body were significantly hypomethylated in atherosclerotic carotid plaque compared to nearby macroscopically intact tissue. Thus, we have shown the tissue specificity at the CpG sites in the MIR21 gene for vessels and its association with carotid artery atherosclerosis.

SUN-LB063 Peripheral Clock System Circadian Imbalance in Cushing's Disease

Context: Glucocorticoid circulating levels in healthy individuals oscillate according to a circadian rhythm, influenced by the molecular system of clock genes. In Cushing's syndrome, there is an altered cortisol daily rhythm, which can be associated to disruption of clock genes rhythmic expression. Objective: Evaluate the expression of clock genes (CLOCK, BMAL1, CRY1, CRY2, PER1, PER2, PER3) in leukocytes of healthy individuals and in patients with Cushing's disease (CD). Design and Participants: Case-control study with female Cushing’s disease patients (n=12) and controls (n=13). Main Outcome Measures: Participants underwent salivary cortisol measurement at 0900h and 2300h. Peripheral blood samples were obtained at 0900h, 1300h, 1700h and 2300h for assessing clock genes expression by qPCR. Gene expression profiles were evaluated by Cosinor analysis method. Results: In healthy controls, there was a circadian variation of the mRNA expression of CLOCK (p<0.01), BMAL1 (p=0.02), CRY1 (p=0.02), PER2 (p<0.01), and PER3 (p<0.01), while no circadian rhythm of PER1, and CRY2 was observed. The expression of PER2 and PER3 genes in control leukocytes showed a late afternoon acrophase at 17.5h (14.9-20.1) and 19.5h (17.9-21.0), respectively, similar to CLOCK gene acrophase at 20.2h (19.0-21.4) while CRY1 showed night acrophase at 22.4h (20.1-24.6) as well as BMAL1 acrophase at 23.6h (21.7-0.49), respectively. In Cushing´s Disease patients, there was a loss of the pattern of clock genes circadian rhythmicity, in concomitance with the loss of cortisol circadian rhythm. One exception was CRY2, which presented a circadian variation (p<0.01), with acrophase during the dark phase at 0.5h (22.5-2.6). Conclusions: Our data suggest that hypercortisolism leads to dysregulation of circadian clock genes expression in Cushing's disease. CRY2 higher expression at night outlines its putative role in the cortisol circadian rhythm disruption. Although the role of clock genes dysregulation in the pathogenesis of Cushing's disease metabolic derangements is still not completely established, it is possible that it synergistically contributes to hypercortisolism to the severity of metabolic features of Cushing's disease. Unless otherwise noted, all abstracts presented at ENDO are embargoed until the date and time of presentation. For oral presentations, the abstracts are embargoed until the session begins. s presented at a news conference are embargoed until the date and time of the news conference. The Endocrine Society reserves the right to lift the embargo on specific abstracts that are selected for promotion prior to or during ENDO.

Inter- and intra-subject variability of nitric oxide levels in leukocyte subpopulations

Assessment of nitric oxide (NO) dynamics in immune cells, commonly measured using NO surrogates such as inducible nitric oxide synthase (iNOS) rather than NO itself, has been effective in understanding pathophysiology across a wide range of diseases. Although the intracellular measurement of NO is now feasible, many technical issues remain unresolved. The principle aim of our study was to determine the effect of storage time of whole blood on nitric oxide (NO) level expression in leukocytes. This is important because immune cells remain chemically dynamic even after they are removed from the circulation, and the impact of storage time must be known to optimally quantify the effect of a disease or condition on NO dynamics in circulating leukocytes. We measured NO levels using the fluorescent probe, diaminofluorescein (DAF-2DA), and flow cytometry in monocytes, neutrophils, and natural killer cells from healthy subjects immediately after blood draw (Time 0) and 30, 60, and 120 min following the blood draw. There was no significant difference among the 4 study time points in NO (DAF-2) levels, though there was wide intra-subject variability at all time points. Using LPS stimulation, we compared iNOS (the more traditional surrogate marker of NO dynamics) with NO (by DAF-2) in natural killer cells and monocytes and, we found no difference in the response patterns. In summary, we did find that within a 2-hour interval from blood draw to sample processing, there was a remarkably wide intra-subject variability in expression of intracellular NO (DAF-2) in leukocytes of healthy individuals at baseline and over time. The mechanism(s) for these differences are not known but could clearly confound efforts to detect changes in NO metabolism in white blood cells. We speculate that rapid pulsatility of NO could explain the wide variability seen.

Type‐2 diabetes down‐regulates glucose transporter proteins and genes of the human blood leukocytes

Objective. White blood cells are essential in mediating immune and inflammatory responses. A prominent feature of these cells during activation of the immune function is increased glucose utilization, and this is dependent on the functioning of specific glucose transporter (GLUT) isoforms. The few data available on leukocyte glucose transporter expression are limited to type‐2 diabetes mellitus, and nothing is known about its regulation. Material and methods. Peripheral blood was drawn from 35 healthy controls and 35 diabetic subjects. Expression of GLUT1, GLUT3 and GLUT4 was determined in the leukocytes of healthy individuals and diabetic patients by flow cytometry, Western blot and semi‐quantitative RT‐PCR. Results. GLUT 3 was decreased in granulocytes, lymphocytes and monocytes from diabetic patients. In monocytes, GLUT3 and GLUT4 were reduced in type‐2 diabetic patients. In leukocytes of diabetic patients, GLUT1 and GLUT4, protein and mRNA were unchanged, but GLUT3 protein and mRNA levels were down‐regulated compared to those of healthy controls. Conclusion. Elevated glucose concentration affects leukocyte GLUT expression. Decreased expression of GLUT isoforms in leukocytes may be responsible for diminished activation of diabetic leukocytes. These situations possibly contribute to a predisposition to infection and to a decreased immune response in diabetes.

Influence of platelet-activating factor, its cell analogs, and antagonist on the production of superoxide radicals by blood leukocytes of healthy and hypercholesterolemic individuals.

The influence of the phospholipid platelet-activating factor (PAF), its cell analogs, and lipid PAF antagonist on the production of superoxide radicals by leukocytes isolated from the blood of healthy and hypercholesterolemia IIA individuals was studied. It was found that endogenous superoxide production level in the leukocytes of hypercholesterolemic individuals more than 4-5 times higher than in the leukocytes of healthy individuals. Exogenous PAF stimulates the superoxide production in the leukocytes of healthy individuals but significantly inhibits the superoxide production in the leukocytes of hypercholesterolemic individuals. The compounds 1-acyl-2-acetyl-sn-glycero-3-phosphocholine (1-acyl-PAF) and 1-alk-1;-enyl-2-acetyl-sn-glycero-3-phosphocholine (1-alkenyl-PAF) only slightly inhibited the endogenous superoxide production in the leukocytes of hypercholesterolemia individuals. However, pretreatment of leukocytes by 1-alkenyl-PAF or PAF-antagonist (1-O-alk-1;-enyl-2-(2;-acetoxybenzoyl)-sn-glycero-3-phosphocholine) results in a 50% inhibition of the PAF-induced superoxide production by leukocytes of healthy individuals. This PAF-antagonist alone or in combination with PAF induces a substantial (65-70%) inhibition of superoxide production in the leukocytes of hypercholesterolemic individuals. It is concluded that superoxide production by leukocytes of healthy individuals and especially by leukocytes of hypercholesterolemic individuals is process that depends on PAF or PAF-like lipids.

Failure to detect human cytomegalovirus DNA in peripheral blood leukocytes of healthy blood donors by the polymerase chain reaction.

The transmission of cytomegalovirus (CMV) by blood transfusion may have a major effect on certain immunocompromised patients. To protect susceptible blood recipients from infection, it is advisable to use blood components from CMV-seronegative donors. However, serologic tests are not capable of indicating which blood component actually harbors infectious virus and can transfer it to the recipient. Therefore, a sensitive method is needed for the detection of the virus itself. There have been three reports on the detection of CMV in healthy volunteer blood donors by the polymerase chain reaction (PCR). CMV DNA was found in all seropositive and most seronegative blood donors. However, many other authors have failed to confirm these data. A highly sensitive and specific PCR assay was developed for the detection of CMV DNA in peripheral blood leukocytes. With this protocol, blood samples from 116 volunteer blood donors were investigated. None of these samples proved to be positive for CMV DNA. In contrast, CMV DNA was detected in 10 of 10 renal transplant patients early in the course of active CMV infection. It can be concluded that the CMV genome copy number in the peripheral blood leukocytes of healthy individuals is beyond the detection limit of current PCR technology.