Changes In Cytokine Responses Research Articles

Cell-free hemoglobin triggers macrophage cytokine production via TLR4 and MyD88.

Cell-free hemoglobin (CFH) is elevated in the airspace of patients with acute respiratory distress syndrome (ARDS) and is sufficient to cause acute lung injury in a murine model. However, the pathways through which CFH causes lung injury are not well understood. Toll-like receptor 4 (TLR4) is a mediator of inflammation after detection of damage- and pathogen-associated molecular patterns. We hypothesized that TLR4 signaling mediates the proinflammatory effects of CFH in the airspace. After intratracheal CFH, BALBc mice deficient in TLR4 had reduced inflammatory cell influx into the airspace [bronchoalveolar lavage (BAL) cell counts, median TLR4 knockout (KO): 0.8 × 104/mL [IQR 0.4-1.2 × 104/mL], wild-type (WT): 3.0 × 104/mL [2.2-4.0 × 104/mL], P < 0.001] and attenuated lung permeability (BAL protein, TLR4KO: 289 µg/mL [236-320], WT: 488 µg/mL [422-536], P < 0.001). These mice also had attenuated production of interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α in the airspace. C57Bl/6 mice lacking TLR4 on myeloid cells only (LysM.Cre+/-TLR4fl/fl) had reduced cytokine production in the airspace after CFH, without attenuation of lung permeability. In vitro studies confirm that WT primary murine alveolar macrophages exposed to CFH (0.01-1 mg/mL) had dose-dependent increases in IL-6, IL-1 β, CXC motif chemokine ligand 1 (CXCL-1), TNF-α, and IL-10 (P < 0.001). Murine MH-S alveolar-like macrophages show TLR4-dependent expression of IL-1β, IL-6, and CXCL-1 in response to CFH. Primary alveolar macrophages from mice lacking TLR4 adaptor proteins myeloid differentiation primary response 88 (MyD88) or TIR-domain-containing adapter-inducing interferon-β (TRIF) revealed that MyD88KO macrophages had 71-96% reduction in CFH-dependent proinflammatory cytokine production (P < 0.001), whereas macrophages from TRIFKO mice had variable changes in cytokine responses. These data demonstrate that myeloid TLR4 signaling through MyD88 is a key regulator of airspace inflammation in response to CFH.NEW & NOTEWORTHY Cell-free hemoglobin (CFH) is elevated in the airspace of most patients with acute respiratory distress syndrome and causes severe inflammation. Here, we identify that CFH contributes to macrophage-induced cytokine production via Toll-like receptor 4 (TLR4) and myeloid differentiation primary response 88 (MyD88) signaling. These data increase our knowledge of the mechanisms through which CFH contributes to lung injury and may inform development of targeted therapeutics to attenuate inflammation.

Literature Review: The Role of Cytokines in the Oral Cavity of Diabetics

Diabetes is a chronic inflammation and can affect various organs, one of which is oral health. The oral cavity in diabetic patients has several symptoms, some of them are dry mouth, periodontal disease, gingivitis, and others. The immune system is a very complex body defense, and provides a variety of responses. The response can be through innate or adaptive immunity. Scientific advances have revealed a wealth of information about the numerous types of cytokines that contribute to this response. Cytokines are small protein molecules secreted by cells that have a specific influence on cell contacts and communication. Some researchers explained that there are several mechanisms of action in diabetes such as the role of macrophages, cytokines such as TNF-alpha, IL-1, IL-6, IL-10, and more. Besides that, diabetes can affect the rate of saliva resulting in various changes in other conditions in the oral cavity. Periodontal disease (PD) is one of the risk variables that can rise if the patient has diabetes, and it is the most common oral problem associated with diabetes. microbiome is another aspect that can contribute to changes in cytokine responses as well as other immunological factors. The relationship between diabetes and oral disease demands an increasing need to research to regulate both diseases and contribute to the advancement of oral medicine.

Combined application of dinitrofluorobenzene and ovalbumin induced AD-like dermatitis with an increase in helper T-cell cytokines and a prolonged Th2 response

BackgroundThe progression of acute-to-chronic atopic dermatitis is accompanied by multiple helper T-cell cytokine responses, but the mechanisms and relative importance of these changes remain unclear. There is no animal model for atopic dermatitis that recapitulates these cytokine responses.ObjectiveWe sought to build a novel mouse model for atopic dermatitis (AD) that recapitulates these helper T-cell responses and some dynamic changes in cytokine responses in the progression of AD.MethodsFemale BALB/c mice were subjected to the application of dinitrofluorobenzene (DNFB) and ovalbumin (OVA) to induce AD-like dermatitis. Skin lesions and serum were collected from mice in the acute and chronic phases to detect changes in cytokine responses and other features of AD.ResultsCombined application of DNFB and OVA successfully induced AD-like dermatitis and histological changes as well as epidermal barrier dysfunction. In the acute phase of AD-like dermatitis, Th2-associated cytokines were mainly increased in serum and skin lesions. In the chronic phase of AD-like dermatitis, Th2-associated cytokines were still highly expressed, while Th1- and Th17-associated cytokines were also gradually increased. Compared with the acute phase, the JAK-STAT signaling pathway was highly expressed in the chronic phase of AD-like dermatitis.ConclusionThe combined application of DNFB and OVA could be used to build a new mouse model for atopic dermatitis. This mouse model recapitulates the helper T-cell responses and some dynamic changes in cytokine responses in the progression of acute-to-chronic in human AD. The JAK-STAT signaling pathway plays a pivotal role in the chronicity of AD.

Abstract 10169: Changes in Cytokine Responses by Treatment with Tocilizumab After Out-of-Hospital Cardiac Arrest - A Sub Study of the IMICA Trial

Background: Out-of-hospital cardiac arrest (OHCA) patients are at high risk of morbidity and mortality attributable to the post-cardiac arrest syndrome, in which systemic inflammation is a major component. Cytokines are involved in many processes, including inflammation. In the IMICA trial, treatment with the interleukin 6 receptor (IL-6R) antagonist tocilizumab in resuscitated comatose OHCA patients reduced systemic inflammation as characterized by a greatly reduced CRP response and lower levels of leukocytes as compared to placebo. Markers of myocardial injury were also reduced by treatment. Aim: To investigate changes in cytokine levels induced by blocking the IL-6-mediated signaling with tocilizumab after OHCA by employing a broad cytokine panel. Methods: We randomized 80 patients to a single infusion of tocilizumab 8 mg/kg or placebo after admission. Blood samples were drawn at 0, 24, 48, and 72 hours. Cytokines were measured using a 17-plex cytokine assay: G-CSF, GM-CSF, IFN-γ, MCP-1, MIP-1β, TNF-α, IL- 1β, 2, 4-8, 10, 12, 13, and 17. Data were log2 transformed and analyzed by constrained linear mixed models. Results: Most cytokines had temporal changes after OHCA. However, only for IL- 5, 6 (Figure) and 17 were the treatment-by-time interactions significant, all p&lt;0.05. Circulating IL-5 and in particular IL-6 was markedly increased by inhibition of the IL-6R with tocilizumab as compared to the placebo group. For IL-17 the changes were less pronounced and only differed between groups at 72 hours. Conclusions: Treatment with the IL-6R antagonist, tocilizumab, did not alter the cytokine responses in general, however, IL-5 and IL-6 were markedly increased. Experimental data suggests that IL-5 may play a role in cardiac recovery after ischemia. Blockage of the IL-6R greatly increased the IL-6 levels, and as the CRP response was greatly reduced by tocilizumab, a response strongly associated with IL-6, it can be demonstrated that the function of IL-6 was blunted.

COVID-19 infection in patients with mast cell disorders including mastocytosis does not impact mast cell activation symptoms

COVID-19 infection in patients with mast cell disorders including mastocytosis does not impact mast cell activation symptoms

Exercise intensity regulates cytokine and klotho responses in men

BackgroundShort-term exercise training programs that consist of moderate intensity endurance training or high intensity interval training have become popular choices for healthy lifestyle modifications, with as little as two weeks of training being shown to improve cardiorespiratory fitness and whole-body glucose metabolism. An emerging concept in exercise biology is that exercise stimulates the release of cytokines and other factors into the blood that contribute to the beneficial effects of exercise on metabolism, but whether these factors behave similarly in response to moderate and high intensity short term training is not known. Here, we determined the effects of two short-term exercise training programs on the concentrations of select secreted cytokines and Klotho, a protein involved in anti-aging.MethodsHealthy, sedentary men (n = 22) were randomized to moderate intensity training (MIT) or sprint intensity training (SIT) treatment groups. SIT consisted of 6 sessions over 2 weeks of 6 × 30 s all out cycle ergometer sprints with 4 min of recovery between sprints. MIT consisted of 6 sessions over 2 weeks of cycle ergometer exercise at 60% VO2peak, gradually increasing in duration from 40 to 60 min. Blood was taken before the intervention and 48 h after the last training session, and glucose uptake was measured using [18F]FDG‐PET/CT scanning. Cytokines were measured by multiplex and Klotho concentrations by ELISA.ResultsBoth training protocols similarly increased VO2peak and decreased fat percentage and visceral fat (P < 0.05). MIT and SIT training programs both reduced the concentrations of IL-6, Hepatocyte Growth Factor (HGF) and Leptin. Interestingly, MIT, but not SIT increased monocyte chemoattractant protein-1 (MCP-1) concentrations, an exercise-induced cytokine, as well as Klotho concentrations.ConclusionShort-term exercise training at markedly different intensities similarly improves cardiovascular fitness but results in intensity-specific changes in cytokine responses to exercise.

The dynamic changes in cytokine responses in COVID-19: a snapshot of the current state of knowledge.

“The role of cytokines in COVID-19” online symposium was presented on 18 June 2020 by the NIH/FDA Immunology and Cytokine Interest Groups and was purposed to discuss our rapidly changing understanding of COVID-19-related cytokine responses in different stages of infection, including the etiologies, downstream consequences and possible mitigation strategies. The recording is available at https://nci.rev.vbrick.com/sharevideo/03106730-66cc-47ba-870b-f6e6274a998a .

Progression of acute-to-chronic atopic dermatitis is associated with quantitative rather than qualitative changes in cytokine responses

Although multiple studies have assessed molecular changes in chronic atopic dermatitis (AD) lesions, little is known about the transition from acute to chronic disease stages, and the factors and mechanisms that shape chronic inflammatory activity. We sought to assess the global transcriptome changes that characterize the progression from acute to chronic stages of AD. We analyzed transcriptome changes in paired nonlesional skin, acute and chronic AD lesions from 11 patients and 38 healthy controls by RNA-sequencing, and conducted invivo and histological assays to evaluate findings. Our data demonstrate that approximately 74% of the genes dysregulated in acute lesions remain or are further dysregulated in chronic lesions, whereas only 34% of the genes dysregulated in chronic lesions are altered already in the acute stage. Nonlesional AD skin exhibited enrichment of TNF, TH1, TH2, and TH17 response genes. Acute lesions showed marked dendritic-cell signatures and a prominent enrichment of TH1, TH2, and TH17 responses, along with increased IL-36 and thymic stromal lymphopoietin expression, which were further heightened in chronic lesions. In addition, genes involved in skin barrier repair, keratinocyte proliferation, wound healing, and negative regulation of T-cell activation showed a significant dysregulation in the chronic versus acute comparison. Furthermore, our data show progressive changes in vasculature and maturation of dendritic-cell subsets with chronicity, with FOXK1 acting as immune regulator. Our results show that the changes accompanying the transition from nonlesional to acute to chronic inflammation in AD are quantitative rather than qualitative, with chronic AD having heightened TH2, TH1, TH17, and IL36 responses and skin barrier repair mechanisms. These findings provide novel insights and highlight underappreciated pathways in AD pathogenesis that may be amenable to therapeutic targeting.

Assessing the function of pneumococcal neuraminidases NanA, NanB and NanC in in vitro and in vivo lung infection models using monoclonal antibodies

ABSTRACT Streptococcus pneumoniae isolates express up to three neuraminidases (sialidases), NanA, NanB and NanC, all of which cleave the terminal sialic acid of glycan-structures that decorate host cell surfaces. Most research has focused on the role of NanA with limited investigations evaluating the roles of all three neuraminidases in host-pathogen interactions. We generated two highly potent monoclonal antibodies (mAbs), one that blocks the enzymatic activity of NanA and one cross-neutralizing NanB and NanC. Total neuraminidase activity of clinical S. pneumoniae isolates could be inhibited by this mAb combination in enzymatic assays. To detect desialylation of cell surfaces by pneumococcal neuraminidases, primary human tracheal/bronchial mucocilial epithelial tissues were infected with S. pneumoniae and stained with peanut lectin. Simultaneous targeting of the neuraminidases was required to prevent desialylation, suggesting that inhibition of NanA alone is not sufficient to preserve terminal lung glycans. Importantly, we also found that all three neuraminidases increased the interaction of S. pneumoniae with human airway epithelial cells. Lectin-staining of lung tissues of mice pre-treated with mAbs before intranasal challenge with S. pneumoniae confirmed that both anti-NanA and anti-NanBC mAbs were required to effectively block desialylation of the respiratory epithelium in vivo. Despite this, no effect on survival, reduction in pulmonary bacterial load, or significant changes in cytokine responses were observed. This suggests that neuraminidases have no pivotal role in this murine pneumonia model that is induced by high bacterial challenge inocula and does not progress from colonization as it happens in the human host.

Changes in cytokine responses to TB antigens ESAT-6, CFP-10 and TB 7.7 and inflammatory markers in peripheral blood during therapy

Multiple cytokines and inflammatory markers control TB infection. We aimed to investigate the changes in multiple cytokines and inflammatory markers in active TB patients following anti-TB drug therapy. Twenty-nine patients with active TB were recruited prospectively between December 2010 and July 2017. Blood samples were collected before (T0), after 2 months (T2), and at the end of anti-TB treatment (Tend). We measured the levels of Interferon (IFN)-γ, interleukin (IL)-2, IL-12, IL-10, IL-13 and tumor necrosis factor (TNF)-α in supernatants collected from the QuantiFERON-TB Gold In-Tube assay (QFT-GIT), as well as the WBC, neutrophil, platelet count and neutrophil to lymphocyte ratio (NLR) in whole blood. Compared with baseline levels, WBC, neutrophil, and platelet counts were significantly lower following treatment. In addition, the NLR after treatment significantly decreased compared with baseline, whereas the IL-2/IFN-γ ratio increased after treatment. In conclusion, the levels of IL-2/IFN-γ ratios in the supernatant and the NLR might be useful biomarkers to evaluate the effectiveness of drug therapy in active TB patients.

Loss in lung volume and changes in the immune response demonstrate disease progression in African green monkeys infected by small-particle aerosol and intratracheal exposure to Nipah virus.

Nipah virus (NiV) is a paramyxovirus (genus Henipavirus) that emerged in the late 1990s in Malaysia and has since been identified as the cause of sporadic outbreaks of severe febrile disease in Bangladesh and India. NiV infection is frequently associated with severe respiratory or neurological disease in infected humans with transmission to humans through inhalation, contact or consumption of NiV contaminated foods. In the work presented here, the development of disease was investigated in the African Green Monkey (AGM) model following intratracheal (IT) and, for the first time, small-particle aerosol administration of NiV. This study utilized computed tomography (CT) and magnetic resonance imaging (MRI) to temporally assess disease progression. The host immune response and changes in immune cell populations over the course of disease were also evaluated. This study found that IT and small-particle administration of NiV caused similar disease progression, but that IT inoculation induced significant congestion in the lungs while disease following small-particle aerosol inoculation was largely confined to the lower respiratory tract. Quantitative assessment of changes in lung volume found up to a 45% loss in IT inoculated animals. None of the subjects in this study developed overt neurological disease, a finding that was supported by MRI analysis. The development of neutralizing antibodies was not apparent over the 8–10 day course of disease, but changes in cytokine response in all animals and activated CD8+ T cell numbers suggest the onset of cell-mediated immunity. These studies demonstrate that IT and small-particle aerosol infection with NiV in the AGM model leads to a severe respiratory disease devoid of neurological indications. This work also suggests that extending the disease course or minimizing the impact of the respiratory component is critical to developing a model that has a neurological component and more accurately reflects the human condition.

Novel pharmacologic treatment attenuates septic shock and improves long-term survival

We have demonstrated previously that suberoylanilide hydroxamic acid (SAHA), a histone deacetylase inhibitor, improves survival in a lipopolysaccharide-induced lethal model of endotoxemia. The goal of this study was to investigate the impact of SAHA on survival in a more clinically relevant model of cecal ligation and puncture (CLP)-induced septic shock and to elucidate changes in cytokine responses and organ injury. C57BL/6J mice were subjected to CLP, and 1 hour later were given intraperitoneally either SAHA dissolved in dimethyl sulfoxide or dimethyl sulfoxide only. Survival was monitored for 10 days. In a second study, livers were harvested for evaluation of acute liver injury, and peritoneal fluid and blood samples were collected for cytokine assays. In addition, RAW264.7 and bone marrow-derived macrophages were used to assess effects of SAHA on cytokine responses. SAHA-treated animals displayed a substantial improvement in survival. In addition, SAHA also attenuated cytokine levels in blood and peritoneal fluid compared with vehicle animals, as well as in culture supernatant of macrophages stimulated with bacterial components (lipopolysaccharide or Pam3CSK4). Moreover, SAHA-treated animals showed a substantial decrease in acute liver injury. SAHA treatment improves survival, decreases "cytokine storm," and prevents distant organ damage in a lethal septic model.

Production of erythrocytes from directly isolated or Delta1 Notch ligand expanded CD34+ hematopoietic progenitor cells: process characterization, monitoring and implications for manufacture

Background aimsEconomic ex vivo manufacture of erythrocytes at 1012 cell doses requires an efficiently controlled bio-process capable of extensive proliferation and high terminal density. High-resolution characterization of the process would identify production strategies for increased efficiency, monitoring and control. MethodsCD34+ cord blood cells or equivalent cells that had been pre-expanded for 7 days with Delta1 Notch ligand were placed in erythroid expansion and differentiation conditions in a micro-scale ambr suspension bioreactor. Multiple culture parameters were varied, and phenotype markers and metabolites measured to identify conserved trends and robust monitoring markers. ResultsThe cells exhibited a bi-modal erythroid differentiation pattern with an erythroid marker peak after 2 weeks and 3 weeks of culture; differentiation was comparatively weighted toward the second peak in Delta1 pre-expanded cells. Both differentiation events were strengthened by omission of stem cell factor and dexamethasone. The cumulative cell proliferation and death, or directly measured CD45 expression, enabled monitoring of proliferative rate of the cells. The metabolic activities of the cultures (glucose, glutamine and ammonia consumption or production) were highly variable but exhibited systematic change synchronized with the change in differentiation state. ConclusionsErythroid differentiation chronology is partly determined by the heterogeneous CD34+ progenitor compartment with implications for input control; Delta1 ligand-mediated progenitor culture can alter differentiation profile with control benefits for engineering production strategy. Differentiation correlated changes in cytokine response, markers and metabolic state will enable scientifically designed monitoring and timing of manufacturing process steps.

Miltefosine triggers a strong proinflammatory cytokine response during visceral leishmaniasis: Role of TLR4 and TLR9

Visceral leishmaniasis (VL) caused by the protozoan parasite, Leishmania donovani, is associated with irregular fever, weight loss, hepatosplenomegaly and anemia. The therapeutic arsenal against VL is limited and the recent advent of a novel immunomodulatory drug, Miltefosine has shown promising results for effective treatment of VL but its dependence on Toll like receptors (TLR) has not been explored. In this study, we have shown that the non-cytotoxic dose (5μM) of Miltefosine could render significant protection corresponding to 88% and 95% reduction in intracellular parasite load at 24h and 48h in L. donovani infected THP1 cells. This was accompanied by a strong proinflammatory cytokine response in the form of IFN-γ, IL-12 and TNF-α as evident by enzyme linked immunosorbent assay (ELISA) and real time PCR (RT-PCR). This Miltefosine induced proinflammatory cytokine response in infected THP1 cells was also accompanied by simultaneous 10- and 12-fold increase in TLR4 mRNA and TLR9 mRNA. These changes in cytokine response and TLR expression were also studied in peripheral blood mononuclear cells (PBMC) of VL patients treated with Miltefosine by RT-PCR which showed similar results as in THP1 cells. Thereby, suggesting a probable dependence of Miltefosine on TLR4 and TLR9 in triggering a proinflammatory response.

A pediatric perspective on inflammation and oxidative stress in response to exercise

Dr. Oded Bar-Or was a giant in the area of pediatric exercise science and made numerous contributions to the health of children around the world. He also had a significant impact on a relatively new area of pediatric exercise science -- pediatric exercise immunology. Under his supervision, some aspects of the immunobiology of exercise have been unravelled from a pediatric perspective. In general, healthy children experience less inflammatory stress in response to standardized exercise, while demonstrating an exercise-induced elevation in the anabolic cytokine IL-8. Mechanisms for the maturity- and age-dependent changes in cytokine responses to exercise are unknown, but may involve oxidative stress. Studies of oxidative stress and exercise in children are scant, but preliminary data suggests that, like the inflammatory cytokine response to exercise, children may experience less oxidative stress in response to intense exercise. We propose that the links between exercise, inflammatory and oxidative stress, and growth factors will be important to understand in the context of how exercise contributes to optimal growth and development during childhood. This understanding will be particularly relevant for childhood diseases that restrict growth.

Cytokine Responses to Treadmill Running in Healthy and Illness-Prone Athletes

To characterize differences in cytokine responses to exercise of different intensities and durations between healthy and illness-prone runners. Trained distance runners were classified as healthy (no more than two episodes of upper-respiratory symptoms per year; N = 10) or illness-prone (four or more episodes per year; N = 8) and completed three treadmill tests: SHORT (30 min, 65% VO2max), LONG (60 min, 65% VO2max), and INTENSE (6 x 3 min, 90% VO2max). Blood samples were collected pre-, post-, 1 h, 10 h, and 24 h after exercise, and interleukin (IL)-2, IL-4, IL-6, IL-8, IL-10, IL-12, and IL-1ra concentrations were determined. Repeated-measures ANOVA was used to assess changes in cytokine responses to exercise. Magnitudes of changes and differences between groups were characterized using Cohen's effect size (ES) criteria. Resting IL-8, IL-10, and IL-1ra concentrations were 19-38% lower (ES:0.38-0.96; small to moderate differences) in illness-prone runners. Similarly, postexercise IL-10 concentrations were 13-20% lower (ES: 0.20-0.37; small differences), and IL-1ra concentrations were 10-20% lower (ES: 0.22-0.38; small differences) in illness-prone subjects. In contrast, IL-6 elevations were 84-185% higher (ES: 0.29-0.59, small differences) in illness-prone subjects. Postexercise responses of IL-2, IL-4, and IL-12 were small and not substantially different between the groups. Cytokine responses to controlled treadmill running differ between healthy and illness-prone athletes. Illness-prone distance runners showed evidence suggestive of impaired inflammatory regulation in the hours after exercise that may account for the greater frequency of upper-respiratory symptoms experienced.

Age‐related difference in immune responses to respiratory syncytial virus infection in young children

There have been longitudinal studies of the developmental change of the immune system during the first year of life. The aim of this study was to investigate if there is any age-related difference in cytokine responses to respiratory syncytial virus (RSV) infection between the patients under 6 months of age and the patients over 12 months of age compared with age-matched controls. Forty-five children < or =24 months of age who were admitted with acute RSV bronchiolitis were enrolled. The patients were divided into two groups: the infants < or =6 months old and the young children > or =12 months old. Immune response to RSV infection was determined by measuring the serum concentrations of cytokines and compared with age-matched controls. Serum samples were obtained on admission and analyzed for interferon (IFN)-gamma, interleukins (IL)-10, -13, and -4 using ELISA. Comparing the cytokine levels of two control groups, both IFN-gamma and IL-13 were lower in the children > or =12 months of age than in the infants < or =6 months of age. IL-10 and IL-4 showed no significant changes with age. Comparing with age-matched controls, IFN-gamma levels were significantly higher in RSV group > or =12 months of age, but showed a tendency toward lower levels in RSV group < or =6 months of age. Both IL-10 and IL-13 levels were significantly higher in RSV group > or =12 months of age, but showed no significant difference in RSV group < or =6 months of age. Our study demonstrated a significant age-related difference in immune response to RSV infection during early life. It suggests that the developmental changes in cytokine responses to RSV infection may be considered in the control of RSV bronchiolitis in young children.

Age-related changes in cytokine production by leukocytes in rhesus monkeys.

Using a variety of experimental rodent and human models, age-related alterations in cytokine production by immune cells have been described extensively. While the precise mechanism(s) responsible for such age-related changes in cytokine responses remain unclear, it seems likely that these changes may have a significant effect on immune cell function. In an attempt to clarify such changes in aging primates, we examined cytokine production by white cells derived from a controlled colony of rhesus monkeys (Macaca mulatta). Non-fractionated whole blood and peripheral blood mononuclear cells (PBMCs) were obtained from male monkeys of different ages (6-28 years), and were subsequently evaluated for their ability to express mRNA and protein for the cytokines, IL-10, IL-6, IFNgamma, IL-1beta, and TNFalpha, following in vitro stimulation with polyclonal mitogens. Our results suggest that white blood cells derived from aged rhesus monkeys exhibit a significant increase in their ability to produce the Th2-associated cytokine, IL-10, upon stimulation with lipopolysaccharide (LPS) when compared to white cells derived from younger counterparts. Similarly, a significant age-related decrease in the expression of the Th1-associated cytokine, IFNgamma, was also observed using phytohemagglutinin (PHA)-stimulated PBMCs. No significant age-related differences in the production of IL-1beta or TNFalpha were observed in response to any stimulation, but there was limited evidence of an age-related increase in IL-6 production. Overall, our results suggest that a possible systemic change from a Th0/Th1 to a Th2-like cytokine profile occurs in circulating leukocytes derived from aging primates. We believe that such age-related alterations in cytokine production may play a role in the reduced immune responses observed in elderly human populations.

Monocyte IL-10 production during respiratory syncytial virus bronchiolitis is associated with recurrent wheezing in a one-year follow-up study.

Respiratory syncytial virus (RSV) bronchiolitis is associated with subsequent recurrent wheezing episodes. To determine whether cytokine responses during infection can be of predictive value for the development of recurrent wheezing, we performed a follow-up study in 50 hospitalized children with RSV bronchiolitis. Monocyte and lymphocyte cytokine responses in vitro were studied during the acute phase of disease, and again during the convalescent phase, 3 to 4 wk later. Monocyte cytokine responses, including interleukin-10 (IL-10), were measured in whole blood cultures, stimulated with lipopolysaccharide and interferon-gamma (LPS + IFN-gamma). In addition, T-cell cytokine responses, including IFN-gamma and IL-4 production, were measured in whole-blood cultures stimulated with phytohemagglutinin (PHA) or alphaCD2 + alphaCD28. Cytokine responses were analyzed in relation to the development of recurrent episodes of wheezing, documented by parents in a diary during a 1-yr follow-up period. IL-10 responses during the acute phase of RSV bronchiolitis were comparable to those in healthy control subjects. During the convalescent phase, IL-10 responses were significantly increased in patients as compared with those in healthy control subjects (p < 0.001). At follow-up, 27 children (58%) had recurrent episodes of wheezing. IL-10 levels, measured during the convalescent phase, were significantly higher in patients who developed recurrent wheezing during the year after RSV bronchiolitis than in patients without recurrent episodes of wheezing (p = 0.006). Moreover, IL-10 responses during the convalescent phase correlated significantly with the number of wheezing episodes (r = 0.42, n = 46, p = 0.004). Interestingly, no association was found between IFN-gamma responses, IL-4 responses, or IFNgamma/IL-4 ratios and recurrent wheezing. We conclude that monocyte IL-10 responses in vitro upon stimulation with nonspecific stimuli may have predictive value for the development of recurrent wheezing after RSV bronchiolitis. Moreover, our results indicate that not only allergen-driven Th2 cytokine responses can lead to asthmatic symptoms but also virus-induced changes in cytokine responses may result in asthmatic symptoms.

Responses of Pro-Inflammatory and Anti-Inflammatory Cytokines with Clonidine Premedication in Patients Undergoing Spinal Surgery

Background : As immune mediators, cytokines are thought to regulate many biological functions. Changes in cytokine response were found in stressful conditions including surgery. Our aim was to study the effects of oral clonidine premedication on the proinflammatory and antiinflammatory cytokines in patients undergoing spinal fusion. Methods : Thirty patients (ASA I and II) were selected and randomly assigned to one of the three groups. Group 1, 2, and 3 received no premedication, clonidine 0.15 mg and 0.3 mg orally, respectively. Blood concentrations of proinflammatory cytokines, tumor necrosis factor- (TNF- ), Interleukin-1 (IL-1 ), IL-6, and antiinflammatory cytokines IL-10, IL-13 were determined as following intervals: before induction, immediate, 1 h, 3 h and 5 h after incision. For cytokines assay, commercially available ELISA kits were used. Results : Compared to baseline values, TNF- , IL-6 and IL-10 concnetrations at 3 h and 5 h after incision increased significantly in all the individual groups. IL-1 increased significantly at 3 h and 5 h after incision in group 1 and 3, and at immediate, 1 h and 3 h after incision in group 2. At the same times sampled, TNF- , IL-1 , IL-6, IL-13 concentrations were not statistically different among three groups. However, IL-10 concentration increased significantly at 5 h after incision in group 2 and 3 compared to group 1. In addition, IL-10 level at 5 h after incision in group 2 was significantly different from group 3. Conclusions : Oral clonidine premedication increased release of antiinflammatory cytokine IL-10 significantly during spinal fusion surgery. (Korean J Anesthesiol 1998; 35: 1080∼1088)