TP1-4 In vitro induced cytokine response of astrocytes modelling conditions in human traumatic brain injury

Objectives

The objective of this study was to investigate how in vitro astrocyte cultures respond to cytokine pro- and anti-inflammatory cytokine concentrations, corresponding to those seen in the aftermath of human TBI, by analysing downstream cytokine generation.

Design

In vitro study.

Subjects

Human induced pluripotent stem cells (iPSC)-derived astrocytes.

Methods

The astrocytes were exposed to levels of TNF (1–10,000 pg/ml), IL-6 (100–1,000,000 pg/ml), Interleukin-1β (IL-1β, 1–10,000 pg/ml), Interleukin-4 (IL-4, 1–10,000 pg/ml) and Interleukin-10 (IL-10, 1–10,000 pg/ml). Following 24, 48 and 72 hours, culture supernatant was extracted and analysed using a human cytokine/chemokine 39-plex luminex assay (ThermoFisher).

Results

The astrocyte secretome revealed concentration-, time- or concentration*time-dependent production of downstream cytokines (12, 8 and 2 cytokines, respectively p<0.05). IL-1β and TNF exposure generated the most downstream cytokine production, while IL-6, IL-4 and IL-10 did not generally induce a robust response.

Conclusions

iPSC-derived astrocytes exposed to cytokine concentrations reflecting those in TBI generate an increased downstream cytokine production, especially when exposed to IL-1β and TNF. This is in contrast to our previous work on neuronal cultures where IL-1β only produced a few down-stream cytokines.1 More work is needed to better understand how different cells in the CNS respond to the neuroinflammatory milieu after TBI alone and in combination.

Recovery of Voice After Reconstruction of the Recurrent Laryngeal Nerve and Adjuvant Nimodipine

Background

Transection injury to the recurrent laryngeal nerve (RLN) has been associated with permanent vocal fold palsy, and treatment has been limited to voice therapy or local treatment of vocal folds. Microsurgical repair has been reported to induce a better function. The calcium channel antagonist nimodipine improves functional recovery after experimental nerve injury and also after cranial nerve injury in patients. This study aims to present voice outcome in patients who underwent repair of the RLN and received nimodipine during regeneration.

Methods

From 2002–2016, 19 patients were admitted to our center with complete unilateral injury to the RLN and underwent microsurgical repair of the RLN. After nerve repair, patients received nimodipine for 2–3 months. Laryngoscopy was performed repeatedly up to 14 months postoperatively. The Voice Handicap Index (VHI) was administered, and patients’ maximum phonation time (MPT) was recorded during the follow-up.

Results

All patients recovered well after surgery, and nimodipine was well tolerated with no dropouts. None of the patients suffered from atrophy of the vocal fold, and some patients even showed a small ab/adduction of the vocal fold on the repaired side with laryngoscopy. During long-term follow-up (>3 years), VHI and MPT normalized, indicating a nearly complete recovery from unilateral RLN injury.

Conclusions

In this cohort study, we report the results of the first 19 consecutive cases at our center subjected to reconstruction of the RLN and adjuvant nimodipine treatment. The outcome of the current strategy is encouraging and should be considered after iatrogenic RLN transection injuries.

Effect of skin-to-skin contact on parents' sleep quality, mood, parent-infant interaction and cortisol concentrations in neonatal care units: study protocol of a randomised controlled trial

INTRODUCTION

Separation after preterm birth is a major stressor for infants and parents. Skin-to-skin contact (SSC) is a method of care suitable to use in the neonatal intensive care unit (NICU) to minimise separation between parents and infants. Less separation leads to increased possibilities for parent-infant interaction, provided that the parents' sleep quality is satisfactory. We aimed to evaluate the effect of continuous SSC on sleep quality and mood in parents of preterm infants born <33 weeks of gestation as well as the quality of parent-infant interaction and salivary cortisol concentrations at the time of discharge.

METHODS AND ANALYSIS

A randomised intervention study with two arms-intervention versus standard care. Data will be collected from 50 families. Eligible families will be randomly allocated to intervention or standard care when transferred from the intensive care room to the family-room in the NICU. The intervention consists of continuous SSC for four consecutive days and nights in the family-room. Data will be collected every day during the intervention and again at the time of discharge from the hospital. Outcome measures comprise activity tracker (Actigraph); validated self-rated questionnaires concerning sleep, mood and bonding; observed scorings of parental sensitivity and emotional availability and salivary cortisol. Data will be analysed with pairwise, repeated measures, Mann Whitney U-test will be used to compare groups and analysis of variance will be used to adjust for different hospitals and parents' gender.

ETHICS AND DISSEMINATION

The study is approved by the Regional Research Ethics Board at an appropriate university (2016/89-31). The results will be published in scientific journals. We will also use conferences and social media to disseminate our findings.

TRIAL REGISTRATION NUMBER

NCT03004677.

OC09 - Early maternal contact has an impact on preterm infants' brain systems that manage stress

Theme: Parenting/parenthood.

INTRODUCTION

Early maternal contact can protect the infants' brain from harmful effects of stress while deprivation increases the stress level and leads to increased sensitivity to stress.

AIM

To evaluate the effects of continuous skin-to-skin contact (SSC) after preterm birth on stress.

METHODS

Late preterm infants from two neonatal care units were randomized to either SSC or standard care. Salivary cortisol was measured in response to a nappy change at one month, and again at four months in response to a still-face procedure.

RESULTS

Infants randomized to SSC had a significantly lower salivary cortisol reactivity at one month and there was a correlation between the mothers' and the preterm infants' salivary cortisol levels at four months.

CONCLUSIONS

The results show that close parental contact and human touch have a buffering effect on the infant's stress reactivity and stimulate a more rapid development of regularity.

Experience of a serious life event increases the risk for childhood type 1 diabetes: the ABIS population-based prospective cohort study

AIMS/HYPOTHESIS

The aim of this study was to prospectively investigate whether psychological stress during childhood may be a risk factor for manifest type 1 diabetes.

METHODS

The All Babies In Southeast Sweden (ABIS) study invited all families with babies born between 1 October 1997 and 30 September 1999 in southeast Sweden to participate. Our study subsample includes 10,495 participants in at least one of the data collections at 2-3, 5-6, 8 and 10-13 years of age not yet diagnosed with type 1 diabetes at inclusion; 58 children were subsequently diagnosed. Age at diagnosis was obtained from the national register SweDiabKids in 2012. Family psychological stress was measured via questionnaires given to the parents assessing serious life events, parenting stress, parental worries and the parent's social support.

RESULTS

Childhood experience of a serious life event was associated with a higher risk of future diagnosis of type 1 diabetes (HR 3.0 [95% CI 1.6, 5.6], p = 0.001) after adjusting for heredity of type 1 diabetes and age at entry into the study. The result was still valid when controlling for heredity of type 2 diabetes, size for gestational age, the parents' education level and whether the mother worked at least 50% of full time before the child's birth (HR 2.8 [95% CI 1.5, 5.4], p = 0.002), and also when childhood BMI was added to the model (HR 5.0 [95% CI 2.3, 10.7], p < 0.001).

CONCLUSIONS/INTERPRETATION

This first prospective study concluded that experience of a serious life event in childhood may be a risk factor for manifest type 1 diabetes.

A randomised trial of continuous skin-to-skin contact after preterm birth and the effects on salivary cortisol, parental stress, depression, and breastfeeding

AIM

To evaluate the effects of almost continuous skin-to-skin contact (SSC) on salivary cortisol, parental stress, parental depression, and breastfeeding.

STUDY DESIGN

This is a randomised study engaging families of late preterm infants (32-35 weeks gestation). Salivary cortisol reactivity was measured in infants during a nappy change at one month corrected age, and in infants and mothers during still-face at four month corrected age. Both parents completed the Swedish Parenthood Stress Questionnaire (SPSQ) at one month and the Edinburgh Postnatal Depression Scale (EPDS) at one and four months. Ainsworth's sensitivity scale was used to control for parental sensitivity.

SUBJECTS

Thirty-seven families from two different neonatal care units in Sweden, randomised to either almost continuous SSC or standard care (SC).

RESULTS

Infants randomised to SSC had a lower salivary cortisol reactivity at one month (p=0.01). There was a correlation between the mothers' and the preterm infants' salivary cortisol levels at four months in the SSC group (ρ=0.65, p=0.005), but not in the SC group (ρ=0.14, p=0.63). Fathers in SSC scored lower on the SPSQ sub-scale spouse relationship problems compared to fathers in SC (p<0.05).

CONCLUSIONS

Almost continuous SSC decreases infants' cortisol reactivity in response to handling, improves the concordance between mothers' and infants' salivary cortisol levels, and decreases fathers' experiences of spouse relationship problems.

Psychological stress in children may alter the immune response

Psychological stress is a public health issue even in children and has been associated with a number of immunological diseases. The aim of this study was to examine the relationship between psychological stress and immune response in healthy children, with special focus on autoimmunity. In this study, psychological stress was based on a composite measure of stress in the family across the domains: 1) serious life events, 2) parenting stress, 3) lack of social support, and 4) parental worries. PBMCs, collected from 5-y-old high-stressed children (n = 26) and from 5-y-old children without high stress within the family (n = 52), from the All Babies In Southeast Sweden cohort, were stimulated with Ags (tetanus toxoid and β-lactoglobulin) and diabetes-related autoantigens (glutamic acid decarboxylase 65, insulin, heat shock protein 60, and tyrosine phosphatase). Immune markers (cytokines and chemokines), clinical parameters (C-peptide, proinsulin, glucose), and cortisol, as an indicator of stress, were analyzed. Children from families with high psychological stress showed a low spontaneous immune activity (IL-5, IL-10, IL-13, IL-17, CCL2, CCL3, and CXCL10; p < 0.01) but an increased immune response to tetanus toxoid, β-lactoglobulin, and the autoantigens glutamic acid decarboxylase 65, heat shock protein 60, and tyrosine phosphatase (IL-5, IL-6, IL-10, IL-13, IL-17, IFN-γ, TNF-α, CCL2, CCL3, and CXCL10; p < 0.05). Children within the high-stress group showed high level of cortisol, but low level of C-peptide, compared with the control group (p < 0.05). This supports the hypothesis that psychological stress may contribute to an imbalance in the immune response but also to a pathological effect on the insulin-producing β cells.

Maternal influence on child HPA axis: a prospective study of cortisol levels in hair

OBJECTIVE

To investigate cortisol concentrations in hair as biomarker of prolonged stress in young children and their mothers and the relation to perinatal and sociodemographic factors.

METHODS

Prospective cohort study of 100 All Babies In Southeast Sweden study participants with repeated measures at 1, 3, 5, and 8 years and their mothers during pregnancy. Prolonged stress levels were assessed through cortisol in hair. A questionnaire covered perinatal and sociodemographic factors during the child's first year of life.

RESULTS

Maternal hair cortisol during the second and third trimester and child hair cortisol at year 1 and 3 correlated. Child cortisol in hair levels decreased over time and correlated to each succeeding age, between years 1 and 3 (r = 0.30, P = .002), 3 and 5 (r = 0.39, P < .001), and 5 and 8 (r = 0.44, P < .001). Repeated measures gave a significant linear association over time (P < .001). There was an association between high levels of hair cortisol and birth weight (β = .224, P = .020), nonappropriate size for gestational age (β = .231, P = .017), and living in an apartment compared with a house (β = .200, P = .049). In addition, we found high levels of cortisol in hair related to other factors associated with psychosocial stress exposure.

CONCLUSIONS

Correlation between hair cortisol levels in mothers and their children suggests a heritable trait or maternal calibration of the child's hypothalamic-pituitary-adrenocortical axis. Cortisol output gradually stabilizes and seems to have a stable trait. Cortisol concentration in hair has the potential to become a biomarker of prolonged stress, especially applicable as a noninvasive method when studying how stress influences children's health.

Neurophysiological evaluation of segmental motor neuron function of the thoracic cord in chronic SCI

STUDY DESIGN

Pilot study.

OBJECTIVES

The aim of the study was to develop a neurophysiological method to diagnose the cranial as well as the caudal level of a complete thoracic spinal cord injury (SCI) with higher precision than today's protocols.

SETTING

SCI unit Karolinska University Hospital, Stockholm, Sweden.

METHODS

Bipolar needle electromyography was recorded in intercostal spaces of five patients with chronic, complete thoracic SCI. Tests were performed during rest, during voluntary activation and during activation of lower body spasticity. Magnetic resonance imaging (MRI) was performed in each patient according to a protocol optimized for imaging near metal implants.

RESULTS

Three distinct patterns were found in each patient. Above the lesion we found voluntary activated, normal motor unit potentials (MUPs). At the neurological level and a varying number of segments below, denervated intercostal segments with fibrillation potentials and positive sharp waves appeared. Below the neurological level, normal MUP activated in concert with lower body spasticity was found. The number of denervated segments showed a significant correlation to the length of spinal cord discontinuity on MRI (r=0.97, P<0.05).

CONCLUSION

Intercostal neurophysiology in combination with MRI optimized for imaging near metal implants can be used to determine the extent of a chronic complete thoracic SCI, both anatomically and functionally. The described method increases the sensitivity to detect delicate neurological changes related to the dynamic of the pathology that follows SCI and may be useful in analyzing outcome in clinical trials.

Cortisol in hair measured in young adults - a biomarker of major life stressors?

Background

Stress as a cause of illness has been firmly established. In public health and stress research a retrospective biomarker of extended stress would be an indispensible aid. The objective of this pilot study was to investigate whether concentrations of cortisol in hair correlate with perceived stress, experiences of serious life events, and perceived health in young adults.

Methods

Hair samples were cut from the posterior vertex area of (n = 99) university students who also answered a questionnaire covering experiences of serious life events, perceived Stress Scale and perceived health during the last three months. Cortisol was measured using a competitive radioimmunoassay in methanol extracts of hair samples frozen in liquid nitrogen and mechanically pulverised.

Results

Mean cortisol levels were significantly related to serious life events (p = 0.045), weakly negatively correlated to perceived stress (p = 0.025, r = -0.061) but nor affected by sex, coloured/permed hair, intake of pharmaceuticals or self-reported health. In a multiple regression model, only the indicator of serious life events had an independent (p = 0.041) explanation of increased levels of cortisol in hair. Out of four outliers with extremely high cortisol levels two could be contacted, both reported serious psychological problems.

Conclusions

These findings suggest that measurement of cortisol in hair could serve as a retrospective biomarker of increased cortisol production reflecting exposure to major life stressors and possibly extended psychological illness with important implications for research, clinical practice and public health. Experience of serious life events seems to be more important in raising cortisol levels in hair than perceived stress.

Detection of human immunodeficiency virus type 1 by using the polymerase chain reaction and a time-resolved fluorescence-based hybridization assay

The polymerase chain reaction (PCR) has many potential applications in the field of nucleic acid diagnostics. In particular, it has been successfully applied to the detection of pathogens present in low copy numbers such as the human immunodeficiency virus type 1. Here we describe a time-resolved fluorescence-based hybridization assay which, combined with the PCR, offers an extremely sensitive method for the detection of nucleic acids. In this assay format, the PCR is run by standard procedures and the subsequent hybridization reaction is carried out in solution by using two oligonucleotide probes, one biotinylated and one labeled with europium (Eu3+). The sandwich hybrids are then collected onto a streptavidin-coated microtitration well, and the bound Eu3+ is measured in a time-resolved fluorometer. This assay is rapid, user friendly, and quantitative and lends itself to automation. The application of this assay to the detection of human immunodeficiency virus type 1 is described.

Detection of antigen-antibody interactions by surface plasmon resonance. Application to epitope mapping

Surface plasmon resonance (SPR) detection requires no labeling of antigen or antibodies and allows quantification of two or more interacting molecular species. The automated SPR instrument used here consists of an optical detection unit, an integrated liquid handling unit, and an autosampler. A first molecule is immobilized to the dextran modified surface of the sensor chip. By sequential introduction, the stepwise formation of multimolecular complexes can then be monitored. A two-site binding assay which allows characterization of MoAb epitope specificities is described. A polyclonal rabbit anti-mouse IgG1 (RAMG1) immobilized to the dextran surface is used to capture the first MoAb from unprocessed hybridoma culture supernatants. After introducing the antigen, the ability of a second MoAb to bind to the antigen is tested. The analysis cycle which is fully automated can be performed more than 100 times using the same RAMG1 surface. Since the detection principle allows monitoring of each reactant in the consecutive formation of a multimolecular complex, multi-site binding experiments can be performed. Five MoAbs recognizing different epitopes on an antigen were shown to bind sequentially, forming a hexamolecular complex. MoAbs were further characterized by inhibition analysis using synthetic peptides derived from the primary structure of their antigen. As a model system MoAbs against recombinant HIV-1 core protein p24 were used in all experiments.

Mitochondrial autoantigens in primary biliary cirrhosis. Association of disease-specific determinants with a subunit of complex I (NADH-ubiquinone reductase) of the inner mitochondrial membrane

Anti-mitochondrial autoantibodies (AMA) from patients with primary biliary cirrhosis (PBC) were analysed for fine specificity by immunoblotting and enzyme-linked immunosorbent assay (ELISA). Inhibition ELISA showed that complex I (NADH-ubiquinone reductase) from beef heart mitochondria completely inhibited the binding of AMA to mitochondrial inner membranes (SMP), indicating that the major mitochondrial antigens are located in complex I. Immunoblot analysis of beef heart SMP, complex I and the iron sulphur (IP) subfraction of complex I revealed several antigens, one of which (75 kDa) reacted with all PBC sera but not with the additional autoimmune sera tested. Resolution of SMP or complex I by two-dimensional electrophoresis yielded in both preparations a polypeptide of 75 kDa with an isoelectric point of 6.4, which reacted with PBC serum and with rabbit antisera raised against the 75,000 subunit of complex I. In immunoblot experiments, the antigenicity of the 75,000 polypeptide in SMP, complex I, and the IP subfraction is increased by prior reduction of the sample with mercaptoethanol. This suggests a similarity to the PBC-specific 'M-2' antigen, which is also sensitive to sulphur reagents. The data indicate that the 75 kDa polypeptide of complex I is a major mitochondrial antigen binding AMA in PBC sera, and allows us to identify the location and probable function of the PBC antigen.

Evidence that the major primary biliary cirrhosis-specific mitochondrial autoantigen is a subunit of complex I of the respiratory chain

Primary biliary cirrhosis (PBC)-specific antigens were purified from beef heart mitochondria by immunoaffinity chromatography. Three major polypeptides (75, 60, and 40 kDa) were detected in the purified antigen fraction both by Coomassie blue staining and by western blot analysis. The 75 kDa antigen was identified as a subunit of Complex I (NADH-ubiquinone reductase) by the following criteria: (1) antibodies against the purified 75 kDa subunit of beef heart Complex I react with the immunoaffinity-purified 75 kDa antigen. (2) the 75 kDa subunit present in isolated Complex I, like that in the immunoaffinity-purified antigen, reacts with PBC sera only after reduction with mercaptoethanol, and (3) the 75 kDa antigen is enriched in isolated Complex I. A relationship between the 75 kDa and the 60 and 40 kDa antigens is suggested, since optimal binding of anti-mitochondrial autoantibodies (AMA) to the latter antigens also requires prior reduction with mercaptoethanol. A fourth major antigen (70 kDa) was also detected by western blot analysis, but only in samples that had not been boiled prior to electrophoresis. This antigen, which is also present in isolated Complex I, resembles the 75, 60, and 40 kDa antigens in its response to mercaptoethanol and its reaction with antibodies against the 75 kDa subunit of Complex I. A scheme is presented which relates all of the PBC antigens to the parent 75 kDa subunit of Complex I, probably as proteolytic products of the latter.

Primary biliary cirrhosis: antigenic specificity of IgM-type mitochondrial antibodies analyzed by immunoblotting and ELISA

The antigenic reactivities of circulating IgM- and IgG-type antimitochondrial antibodies (AMA) from 18 patients with primary biliary cirrhosis (PBC) were compared by the use of immunoblotting and enzyme-linked immunosorbent assay (ELISA). In immunoblotting, the binding patterns of IgM and IgG were very similar when F1-ATPase and mitochondria were used as antigens. The major PBC-specific IgM-reactive antigen was identical with the dominating IgG-reactive antigen, sharing the same molecular weight of 70 kD and the same requirement for reduced thiol groups for expression of antigenicity. Other PBC-related mitochondrial proteins with variable antigenicity had the molecular weights of 60 and 43 kD. Depending on the IgM and IgG reactions in F1-ELISA, PBC patients can be grouped into three categories: patients with IgG and IgM (12/18), IgG alone (5/18) and IgM alone (1/18). By serum fractionation, the IgM reactivity was shown to be a true PBC-related antibody antigen reaction, and not due to interference of rheumatoid factors.

Primary biliary cirrhosis: assessment of the quantitative importance of the adenine nucleotide translocator protein as a major mitochondrial antigen

The adenine nucleotide translocator protein (ANT) is the first well-characterized mitochondrial polypeptide to be identified as an antigen for antimitochondrial autoantibodies (AMA) in PBC sera. Because of the potential use for a highly purified antigen as a tool in studying the aetiology of PBC, we have undertaken an assessment of the quantitative importance of ANT as a PBC-specific mitochondrial antigen. Immunoblotting and ELISA techniques were used. Both methods reveal PBC antibodies against isolated rat liver ANT. However, competitive ELISA experiments using purified rat liver ANT as the competing antigen show that anti-ANT antibodies in PBC serum comprise only a fraction of the total AMA. Furthermore, both ELISA and immunoblotting experiments show that rat liver ANT is not a specific antigen for PBC autoantibodies. Sera from patients with SLE, chronic active hepatitis, and sera from normal, control patients, have nearly the same, or higher, ANT antibody titres. Thus, ANT is not a good candidate as an antigen for the diagnosis of PBC.