Altered Levels of Natural Autoantibodies against Heat Shock Proteins in Pregnant Women with Hashimoto's Thyroiditis.

The function of natural autoantibodies (nAAbs) in maintaining immunological tolerance has been comprehensively explained; however, their function in pregnant patients dealing with autoimmune diseases has not been thoroughly investigated. As Hashimoto's thyroiditis (HT) is the predominant organ-specific autoimmune condition of women of childbearing age, this study's objective was to evaluate IgM and IgG nAAbs targeting mitochondrial citrate synthase (CS) and heat shock proteins (Hsp60 and Hsp70) in women diagnosed with HT who were pregnant (HTP). Serum samples collected from HTP and healthy pregnant (HP) women in the first and third trimesters were tested using in-house-developed enzyme-linked immunosorbent assays (ELISAs). Our findings indicate the stability of nAAbs against CS and Hsps throughout the pregnancies of both healthy women and those with HT. However, during both trimesters, HTP patients displayed elevated levels of IgM isotype nAAbs against Hsp60 and Hsp70 compared to HP women, suggesting a regulatory role of IgM nAAbs during the pregnancies of patients with HT. Nonetheless, levels of IgG isotype nAAbs against Hsps were lower solely in the third trimester among HTP patients, resulting in a higher IgM/IgG ratio, which indicates their importance in alterations of the nAAb network during pregnancy in patients with HT.

Physiological Changes in the Levels of Anti-Cytokine Autoantibodies in Early Pregnancy Are Missing in Pregnant Women with Hashimoto's Thyroiditis.

T helper type 1 (Th1) and inflammatory cytokines play essential roles in early pregnancy and also in the pathogenesis of Hashimoto's thyroiditis (HT). Changes in the serum level of autoantibodies to cytokines, which may be able to modulate their availability and actions have been described in several autoimmune disorders. Yet, no data are available on anti-cytokine autoantibodies either during early pregnancy or in patients with HT. The aim of the study was to measure autoantibodies to inflammatory-, Th1- and Th22-cytokines in serum samples in healthy pregnancy (HP) and in pregnant women with HT (HTP). As pathological autoantibodies are hallmarks of HT, in addition we also measured anti-B-cell activator factor (BAFF) autoantibodies. The measurement was carried out with a Luminex multiplex assay and the Luminex MAGPIX Instrument, age-matched healthy women (HC) and women with HT (HT) were used as controls. In the first trimester of HP, anti-TNFα, anti-IL-8, and anti-IFNγ autoantibodies were significantly decreased, while autoantibodies to BAFF were significantly elevated compared to the HC. However, these alterations were not present in the HTP. Moreover, the levels of autoantibodies to IL-22 and TNFα were significantly increased in HTP compared to the HP. All differences in the levels of the investigated autoantibodies could be detected in the first trimester of pregnancies except for anti-IL-22 autoantibodies. According to our results we can conclude that alterations in the levels of autoantibodies to inflammatory and Th1 cytokines are physiological in the first trimester of pregnancy and their disturbance can be associated with autoimmune conditions such as HT.

An Optimized Flow Cytometric Method to Demonstrate the Differentiation Stage-Dependent Ca2+ Flux Responses of Peripheral Human B Cells.

Calcium (Ca2+) flux acts as a central signaling pathway in B cells, and its alterations are associated with autoimmune dysregulation and B-cell malignancies. We standardized a flow-cytometry-based method using various stimuli to investigate the Ca2+ flux characteristics of circulating human B lymphocytes from healthy individuals. We found that different activating agents trigger distinct Ca2+ flux responses and that B-cell subsets show specific developmental-stage dependent Ca2+ flux response patterns. Naive B cells responded with a more substantial Ca2+ flux to B cell receptor (BCR) stimulation than memory B cells. Non-switched memory cells responded to anti-IgD stimulation with a naive-like Ca2+ flux pattern, whereas their anti-IgM response was memory-like. Peripheral antibody-secreting cells retained their IgG responsivity but showed reduced Ca2+ responses upon activation, indicating their loss of dependence on Ca2+ signaling. Ca2+ flux is a relevant functional test for B cells, and its alterations could provide insight into pathological B-cell activation development.

B cells from anti-thyroid antibody positive, infertile women show hyper-reactivity to BCR stimulation.

Anti-thyroid antibody (ATA) positivity affects 1 out of 9 women in childbearing age and presents a significant risk for infertility. Emerging evidence indicates that alterations in the B cell receptor induced calcium (Ca2+) signaling could be key in the development of autoimmunity. We aimed to investigate the Ca2+ flux response of B lymphocyte subsets to BCR stimulation in Hashimoto's thyroiditis and related infertility. We collected peripheral blood samples from ATA+, infertile, euthyroid patients (HIE), hypothyroid, ATA+ patients before (H1) and after levothyroxine treatment (H2), and age-matched healthy controls (HC). All B cell subsets of ATA+, infertile, euthyroid patients showed elevated basal Ca2+ level and hyper-responsivity to BCR ligation compared to the other groups, which could reflect altered systemic immune function. The Ca2+ flux of hypothyroid patients was similar to healthy controls. The levothyroxine-treated patients had decreased prevalence of CD25+ B cells and lower basal Ca2+ level compared to pre-treatment. Our results support the role of altered Ca2+ flux of B cells in the early phase of thyroid autoimmunity and infertility.

Effects of caffeine and phosphodiesterase inhibitors on activation of neonatal T lymphocytes.

Caffeine and selective PDE inhibitors are widely used in clinical management of preterm and term neonates. However, little is known about how these compounds interact with the neonatal adaptive immune system. We aimed to describe the effects of caffeine, milrinone and sildenafil on the activation and cytokine production of T cells from umbilical cord blood (UCB) compared to adult peripheral blood (APB). We isolated mononuclear cells from 10 APB and 6 UCB samples. We assessed intracellular cytokine production (IFN-γ, IL-2, IL-4, IL-6, IL-17) of stimulated CD4 cells and parameters of calcium influx and ROS production following treatment with caffeine, milrinone, sildenafil, dbcAMP or a specific A2A receptor antagonist, ZM241385 using flow cytometry. In ABP, only ZM241385 caused a 1.14-fold increase in calcium influx, while all compounds increased calcium influx in UCB. This effect was more pronounced in case of caffeine (1.41-fold) and dbcAMP (1.3-fold) compared to milrinone (1.22-fold), sildenafil (1.23-fold) or ZM241385 (1.23-fold). Intracellular levels of the studied cytokines were unaffected by the applied compounds in both APB and UCB samples. Caffeine increases calcium influx upon activation in neonatal T lymphocytes to a larger extent than milrinone or sildenafil. This effect appears to be mediated primarily via increased cAMP levels rather than A2A receptor inhibition. Overall, the application of caffeine, sildenafil or milrinone does not appear to have immunosuppressive effects on neonatal T cells.

Cytokine production pattern of T lymphocytes in neonatal arterial ischemic stroke during the first month of life-a case study.

BACKGROUND: The perinatal period carries the highest risk for stroke in childhood; however, the pathophysiology is poorly understood and preventive, prognostic, and therapeutic strategies are not available. A new pathophysiological model describes the development of neonatal arterial ischemic stroke (NAIS) as the combined result of prenatal inflammation and hypoxic-ischemic insult. Neuroinflammation and a systemic inflammatory response are also important features of NAIS. Identifying key players of the inflammatory system is in the limelight of current research. CASE PRESENTATION: We present four NAIS cases, in whom detailed analysis of intracellular and plasma cytokine levels are available from the first month of life. All neonates were admitted with the initial diagnosis of hypoxic ischemic encephalopathy (HIE); however, early MRI examination revealed NAIS. Blood samples were collected between 3 and 6 h of life, at 24 h, 72 h, 1 week, and 1 month of life. Peripheral blood mononuclear cells were assessed with flow cytometry and plasma cytokine levels were measured. Pooled data from the cohort of four NAIS patients were compared to infants with HIE. At 6 and 72 h of age, the prevalence of IL10+ CD8+ lymphocytes remained lower in NAIS. At 6 h, CD8+ lymphocytes in NAIS produced more IL-17. At 72 h, CD8+ cells produced more IL-6 in severe HIE than in NAIS, but IL-6 production remained elevated in CD8 cells at 1 month in NAIS, while it decreased in HIE. At 1 week, the prevalence of TGF-ß + lymphocytes prone to enter the CNS was elevated in NAIS. On the other hand, by 1 month of age, the prevalence of TGF-ß + CD4+ lymphocytes decreased in NAIS compared to HIE. At 72 h, we found elevated plasma levels of IL-5, MCP-1, and IL-17 in NAIS. By 1 month, plasma levels of IL-4, IL-12, and IL-17 decreased in NAIS but remained elevated in HIE. CONCLUSIONS: Differences in the cytokine network are present between NAIS and HIE. CD8 lymphocytes appear to shift towards the pro-inflammatory direction in NAIS. The inflammatory response appears to be more pronounced at 72 h in NAIS but decreases faster, reaching lower plasma levels of inflammatory markers at 1 month.

The Impact of Anti-TNF Therapy on CD4+ and CD8+ Cell Subsets in Ankylosing Spondylitis.

OBJECTIVES: Ankylosing spondylitis (AS) is a chronic, progressive immune-mediated inflammatory disease, driven primarily by Th1 and Th17 cells. Anti-TNF therapies are successfully used in AS to achieve and maintain remission. However, their influence on the composition of T-cell subsets is not clear. We aimed to characterize the changes in the T-cell repertoire after a long-term anti-TNF treatment in AS patients. METHODS: Twenty-two AS patients under long-term anti-TNF therapy were evaluated (15 anti-TNF responders and 7 nonresponders). A wide range of cell subtypes was analyzed with flow cytometry and compared with therapy-naïve and short-term data too. RESULTS: Key findings include decreased proportions of naïve CD4 and CD8 cells, increased frequencies of Th1 and Th17 cells and higher Th1/Th2 ratios in the long-term anti-TNF-treated patients (responders, nonresponders and total), which was found to be significant not only when compared with healthy controls, but also with therapy-naïve and short-term anti-TNF-treated AS patients. We noted several alterations within the various activated T-cell subsets - increase in CD4HLADR cells in responders, in CD8HLADR cells in the whole AS group and in responders, and in CD4CD25 cells in responders, and decrease in CD4CD69 cell percentages in long-term treated patients - becoming evident only after long-term anti-TNF therapy. CONCLUSIONS: This study provides a comprehensive assessment of the impact of anti-TNF therapy on the T-cell repertoire in AS. Changes in T-cell phenotype seem to develop progressively during therapy, even in inactive disease, and reflect an ongoing effector T-cell differentiation and activation, along with the parallel compensatory increase in regulatory T cells.

Distinct cytokine patterns may regulate the severity of neonatal asphyxia-an observational study.

BACKGROUND: Neuroinflammation and a systemic inflammatory reaction are important features of perinatal asphyxia. Neuroinflammation may have dual aspects being a hindrance, but also a significant help in the recovery of the CNS. We aimed to assess intracellular cytokine levels of T-lymphocytes and plasma cytokine levels in moderate and severe asphyxia in order to identify players of the inflammatory response that may influence patient outcome. METHODS: We analyzed the data of 28 term neonates requiring moderate systemic hypothermia in a single-center observational study. Blood samples were collected between 3 and 6 h of life, at 24 h, 72 h, 1 week, and 1 month of life. Neonates were divided into a moderate (n = 17) and a severe (n = 11) group based on neuroradiological and amplitude-integrated EEG characteristics. Peripheral blood mononuclear cells were assessed with flow cytometry. Cytokine plasma levels were measured using Bioplex immunoassays. Components of the kynurenine pathway were assessed by high-performance liquid chromatography. RESULTS: The prevalence and extravasation of IL-1b + CD4 cells were higher in severe than in moderate asphyxia at 6 h. Based on Receiver operator curve analysis, the assessment of the prevalence of CD4+ IL-1ß+ and CD4+ IL-1ß+ CD49d+ cells at 6 h appears to be able to predict the severity of the insult at an early stage in asphyxia. Intracellular levels of TNF-α in CD4 cells were increased at all time points compared to 6 h in both groups. At 1 month, intracellular levels of TNF-α were higher in the severe group. Plasma IL-6 levels were higher at 1 week in the severe group and decreased by 1 month in the moderate group. Intracellular levels of IL-6 peaked at 24 h in both groups. Intracellular TGF-ß levels were increased from 24 h onwards in the moderate group. CONCLUSIONS: IL-1ß and IL-6 appear to play a key role in the early events of the inflammatory response, while TNF-α seems to be responsible for prolonged neuroinflammation, potentially contributing to a worse outcome. The assessment of the prevalence of CD4+ IL-1ß+ and CD4+ IL-1ß+ CD49d+ cells at 6 h appears to be able to predict the severity of the insult at an early stage in asphyxia.

The Distribution of Activation Markers and Selectins on Peripheral T Lymphocytes in Preeclampsia.

INTRODUCTION: Impaired maternal immune tolerance resulting in systemic inflammation plays a pivotal role in the pathogenesis of preeclampsia. Phenotypical changes of monocytes and neutrophil granulocytes have already been studied in preeclampsia, and some studies also included T lymphocyte activation markers; however, the results are controversial and a comprehensive analysis of activation markers is lacking. The characteristics of cellular adhesion molecules in preeclampsia are yet to be described. MATERIAL AND METHODS: Peripheral blood samples of 18 preeclamptic patients and 20 healthy pregnant women in the third trimester were evaluated using flow cytometry to characterize the cell surface expression of T lymphocyte activation markers and selectins. RESULTS: We found an elevated ratio of HLA-DR and CD122-, CD62E-, and CD62L-expressing cells among the CD4+ T lymphocytes in PE in comparison to healthy pregnancy. No alterations were found in the prevalence of CD69-, CD25-, and CD62P-expressing lymphocytes and CD11c-expressing monocytes. CONCLUSIONS: Our findings support the role of activated T lymphocytes and specific cell adhesion molecules in the pathogenesis of preeclampsia.

Altered activation of peripheral CD8+ T cells in pediatric Crohn's disease.

AIM: Although Crohn's disease (CD) is an extensively investigated autoimmune condition, knowledge on early phase activation of lymphocytes, especially CD8+ Tc cells is scarce. Our aim was to investigate the calcium influx characteristics of CD8+ cells upon activation as well as the expression and function of Kv1.3 and IKCa1 lymphocyte potassium channels. METHODS: We took peripheral blood from 12 healthy controls, 23 CD children on conventional therapy and 6 severe CD children before and after infliximab therapy. Intracellular calcium levels were monitored in CD8+ lymphocytes using flow cytometry. RESULTS: In CD treated with standard therapy calcium response during activation was elevated. This was not affected by the inhibition of Kv1.3 or IKCa1 potassium channels. After the switch to infliximab potassium channel function and expression of CD8+ lymphocytes were comparable to healthy controls in severe CD. CONCLUSION: Calcium handling of CD8+ lymphocytes is altered in pediatric CD, which is normalized by infliximab therapy.

Altered calcium influx of peripheral Th2 cells in pediatric Crohn's disease: infliximab may normalize activation patterns.

OBJECTIVE: Crohn's disease is a chronic inflammation of the gastrointestinal tract with an abnormal immune phenotype. We investigated how intracellular calcium kinetics of Th1 and Th2 lymphocytes alter upon specific inhibition of Kv1.3 and IKCa1 channels in pediatric Crohn's disease. STUDY DESIGN: Blood was taken from 12 healthy and 29 Crohn's disease children. Of those, 6 were switched to infliximab and re-sampled after the 4th infliximab treatment. Intracellular calcium levels were monitored using flow cytometry in the presence or absence of specific inhibitors of Kv1.3 and IKCa1 potassium channels. RESULTS: In Crohn's disease treated with standard therapy, calcium response during activation was higher than normal in Th2 cells. This was normalized in vitro by inhibition of Kv1.3 or IKCa1 potassium channels. After the switch to infliximab, potassium channel function and expression in Th2 lymphocytes were comparable to those in Th1 cells. CONCLUSION: These results may indicate that potassium channels are potential immune modulatory targets in Crohn's disease.

Calcium influx kinetics, and the features of potassium channels of peripheral lymphocytes in primary Sjögren's syndrome.

OBJECTIVE: The transient increase of the cytoplasmic free calcium level plays a key role in the process of lymphocyte activation. Kv1.3 and IKCa1 potassium channels are important regulators of the maintenance of calcium influx and present a possible target for selective immunomodulation. DESIGN: Case-control study. SUBJECTS AND METHODS: We took peripheral blood samples from 8 healthy individuals and 15 primary Sjögren's syndrome (pSS) patients. We evaluated calcium influx kinetics following activation in peripheral T lymphocytes. We also assessed the sensitivity of T lymphocytes to specific inhibition of the Kv1.3 and IKCa1 potassium channels, and the Kv1.3 channel expression. RESULTS: The basal cytoplasmatic calcium levels were lower in both Th1 and Th2 lymphocytes in pSS compared to controls. The peak of calcium influx in lymphocytes isolated from pSS patients is reached later, indicating that they respond more slowly to stimulation compared to controls. In healthy individuals, the inhibition of the IKCa1 channel decreased calcium influx in Th2 and CD4 cells to a lower extent than in Th1 and CD8 cells. On the contrary, the inhibition of Kv1.3 channels resulted in a larger decrease of calcium entry in Th2 and CD4 than in Th1 and CD8 cells. In the pSS group, neither of the inhibitors induced alteration in calcium influx. Expression of Kv1.3 channels on CD4, Th2 and CD8 lymphocytes in pSS was significantly higher compared to controls. CONCLUSION: The altered expression and specific inhibition of potassium channels seem to be related to altered calcium influx kinetics in pSS which distinguish pSS either from healthy controls or other systemic autoimmune diseases.

Real time kinetic flow cytometry measurements of cellular parameter changes evoked by nanosecond pulsed electric field.

Nanosecond pulsed electric field (nsPEF) is a novel method to increase cell proliferation rate. The phenomenon is based on the microporation of cellular organelles and membranes. However, we have limited information on the effects of nsPEF on cell physiology. Several studies have attempted to describe the effects of this process, however no real time measurements have been conducted to date. In this study we designed a model system which allows the measurement of cellular processes before, during and after nsPEF treatment in real time. The system employs a Vabrema Mitoplicator(TM) nsPEF field generating instrument connected to a BD Accuri C6 cytometer with a silicon tube led through a peristaltic pump. This model system was applied to observe the effects of nsPEF in mammalian C6 glioblastoma (C6 glioma) and HEK-293 cell lines. Viability (using DRAQ7 dye), intracellular calcium levels (using Fluo-4 dye) and scatter characteristics were measured in a kinetic manner. Data were analyzed using the FACSKin software. The viability and morphology of the investigated cells was not altered upon nsPEF treatment. The response of HEK-293 cells to ionomycin as positive control was significantly lower in the nsPEF treated samples compared to non-treated cells. This difference was not observed in C6 cells. FSC and SSC values were not altered significantly by the nsPEF treatment. Our results indicate that this model system is capable of reliably investigating the effects of nsPEF on cellular processes in real time. © 2016 International Society for Advancement of Cytometry.

Higher Incidence of Stroke on the Last Day of the Month in Hungary-a Role for Psychosocial Factors and Financial Insecurity?

BACKGROUND: The seasonal cumulation of acute ischemic stroke events is a well-known phenomenon. Critical days are determined by both biological and psychosocial factors. We hypothesized that the financial stability of those with a monthly income living in an economically unpredictable environment rises upon the arrival of their salary and decreases in the preceding days, leading to anxiety and existential insecurity, which may increase the incidence of acute ischemic stroke. METHODS: We assessed the daily average number of thrombolytic treatments due to acute ischemic stroke in Hungary between December 1, 2005, and November 30, 2013, calculating the ratio of thrombolytic treatments on the last day of the month (irrespectively whether it was the 28th-31st days) to thrombolytic treatments on the other days, and determined 95% confidence intervals. RESULTS: In this period, 7880 thrombolytic treatments were performed nationwide (2.70/day), out of which 1867 occurred on the last day of the month (19.45/day). If the 28th, 29th, or 30th was not the last day of the month, 15.8, 20.6, and 22 times less thrombolytic treatments, respectively, were performed than on the last day of that month. CONCLUSION: We propose that financial insecurity on the days prior to the receipt of a salary might play a role in the elevation of stroke incidence observed on the last day of the month in Hungary. Further analysis of this phenomenon and its psychosocial effects is needed to adequately allocate healthcare resources and to take preventive measures in the high-risk population.

Prevalence of Regulatory T-Cell Subtypes in Preeclampsia.

PROBLEM: The prevalence of regulatory T cells (Tregs) is lower in preeclampsia (PE) compared with healthy pregnancy (HP). However, the proportion of recently described Treg subtypes has not been investigated. METHOD: Peripheral blood samples of 19 PE and 21 HP women in the third trimester were evaluated using flow cytometry for the prevalence of activated T cells and naive, effector, thymic, extrathymic, and exhausted Tregs. RESULTS: The prevalence of activated T cells and exhausted Tregs was higher in PE than in HP. The prevalence of the functionally most active effector Tregs is decreased, while naive Tregs appear to be unaffected in PE compared with HP. No difference was detected between Tregs according to their origin (thymic or extrathymic). CONCLUSION: The combination of lower effector Treg and higher exhausted Treg prevalence may account for the decrease in the functionality of Tregs in PE.

B7 costimulation and intracellular indoleamine-2,3-dioxygenase (IDO) expression in peripheral blood of healthy pregnant and non-pregnant women.

BACKGROUND: B7 costimulatory molecules are expressed on antigen presenting cells (APCs) and are important regulators of T cell activation. We investigated the role of the B7 family of costimulatory molecules in the development of the systemic maternal immune tolerance during healthy pregnancy (HP). We also aimed to investigate the intracellular expression of indoleamine-2,3-dioxygenase (IDO) and plasma levels of tryptophane (TRP), kynurenine (KYN) and kynurenic acid (KYNA), important molecules with immunoregulatory properties, in order to describe their potential contribution to the pregnancy-specific maternal immune tolerance. METHODS: We determined the frequency of activated (CD11b+) monocytes expressing B7-1, B7-2, B7-H1, and B7-H2, and that of T cells and CD4+ T helper cells expressing CD28, CTLA-4, PD-1, and ICOS in peripheral blood samples of healthy pregnant (HP) and non-pregnant (NP) women using flow cytometry. We also examined the intracellular expression of IDO applying flow cytometry and plasma levels of TRP, KYN and KYNA using high-performance liquid chromatography. RESULTS: A significant increase in the prevalence of CD28+ T cells was observed in HP compared to NP women. At the same time a decrease was shown in the expression of CTLA-4 on these cells. The frequency of CD80+ monocytes was lower in HP women. The prevalence of IDO-expressing T cells and monocytes was higher in HP compared to NP women. Plasma KYN, KYNA and TRP levels were lower, while at the same time, the KYN/TRP ratio was higher in HP than in NP women. CONCLUSIONS: Costimulation via CD28 may not contribute to the immunosuppressive environment, at least in the third trimester of pregnancy. The development of the pregnancy-specific immune tolerance in the mechanism of B7 costimulation may be more related to the altered expression of B7 proteins on APCs rather than that of their receptors on T cells. The elevated intracellular IDO expression in monocytes and T cells, as well as higher plasma enzymatic IDO activity are likely to contribute to the systemic immunosuppressive environment in the third trimester characteristic for healthy gestation.

Kv1.3 lymphocyte potassium channel inhibition as a potential novel therapeutic target in acute ischemic stroke.

Stroke-induced immunosuppression (SIIS) leads to severe complications in stroke patients, including an increased risk of infections. However, functional alterations of T lymphocytes during SIIS are poorly described in acute ischemic stroke (AIS). We aimed to characterize Ca(2+) influx kinetics in major lymphocyte subsets (CD4, Th1, Th2, CD8) in AIS patients without infection 6 hours and one week after the CNS insult. We also assessed the sensitivity of the above subsets to specific inhibition of the Kv1.3 and IKCa1 lymphocyte K(+) channels. We took peripheral blood samples from 12 non-stroke individuals and 12 AIS patients. We used an innovative flow cytometry approach to determine Ca(2+) influx kinetics and the surface expression of Kv1.3 channels. Our results indicate that Ca(2+) influx kinetics is altered in the Th2 and CD8 subsets in AIS which may play a role in the development of SIIS. Specific inhibition of Kv1.3 channels selectively decreased Ca(2+) influx in the CD8 and Th2 subsets of AIS patients. The surface expression of Kv1.3 channels is also altered compared to non-stroke individuals. Kv1.3 channel inhibition might have beneficial therapeutic consequences in AIS, selectively targeting two distinct T cell subsets at two different time points following the CNS insult. Within hours after the insult, it might prevent excessive tissue injury through the inhibition of CD8 cells, while at one week after the insult, it may improve the inflammatory response through the inhibition of Th2 cells, thus reducing the unwanted clinical consequences of SIIS.

Different calcium influx characteristics upon Kv1.3 and IKCa1 potassium channel inhibition in T helper subsets.

Functional imbalance between T helper subsets plays important role in the pathogenesis of autoimmune disorders. Transient increase of cytoplasmic calcium level, and sustention of negative membrane potential by voltage sensitive Kv1.3 and calcium-dependent IKCa1 potassium channels are essential for short-term lymphocyte activation, thus present possible target for selective immunomodulation. We aimed to investigate calcium influx sensitivity to the inhibition of potassium channels in the main T helper subsets. Peripheral blood from 11 healthy individuals was drawn and calcium influx kinetics following activation with phytohemagglutinin in Th1, Th2, Th17, and Treg cells were evaluated. Alteration of calcium influx induced by specific inhibitors of Kv1.3 and IKCa1 potassium channels, and the expression of Kv1.3 channels were also assessed. Highest cytoplasmic calcium concentration was observed in stimulated Th1 cells, while the lowest level was measured in Treg cells. In Th1 and Th17 cells, inhibition of both investigated potassium channels decreased calcium influx. In Th2 cells only the inhibitor of Kv1.3 channels, while in Treg cells none of the inhibitors had significant effect. Upon the inhibition of IKCa1 channels, short-term activation of proinflammatory cells was specifically decreased without affecting anti-inflammatory subsets, indicating that selective immunomodulation is possible in healthy individuals.

Relevance of novel inflammatory markers in stroke-induced immunosuppression.

BACKGROUND: Acute ischemic stroke (AIS) has a biphasic effect on the peripheral immune system. The initial inflammatory response is followed by systemic immunosuppression, referred to as stroke-induced immunosuppression (SIIS), leading to severe complications in stroke patients. We aimed to identify an inflammatory marker that best represents this biphasic immunological response after AIS. METHODS: We investigated the alteration of CRP, WBC, neutrophil count, suPAR levels, CD4+ CD25high Tregs, CD64+ and CD177+ neutrophils and monocytes in 12 acute ischemic stroke patients free of infection within 6 hours and one week after the insult. As controls, 14 age-matched healthy individuals were included. RESULTS: CRP, WBC and neutrophil count values were comparable in stroke patients within 6 hours and controls, however, they were elevated in stroke one week after the insult. suPAR levels were higher in both stroke groups compared to controls. The prevalence of CD64+ neutrophils was higher in stroke patients within 6 hours than in controls and it decreased in stroke one week after the insult below the level in controls (5.95 [5.41-8.75] % vs. 32.38 [9.21-43.93] % vs. 4.06 [1.73-6.77] %, p < 0.05). CONCLUSIONS: Our pilot study identified that the prevalence of CD64+ neutrophils may reflect a biphasic alteration of the immune response following AIS. Since its level decreases below baseline after one week of the CNS insult in stroke patients without infection, it might serve as a reliable candidate to identify the developing inflammatory response due to infection after stroke in the future.