BACKGROUND

Interleukin-6 (IL-6), interleukin-8 (IL-8), and adhesion molecules have been implicated as mediators in neutrophil (PMN) and endothelial cell (EC) interactions leading to postinjury multiple organ failure (MOF). Our hypothesis was that circulating levels of IL-6, IL-8, and soluble intercellular adhesion molecule-1 (sICAM-1) would discriminate patients at risk for postinjury MOF.

METHODS

Serial plasma levels of IL-6, IL-8, and sICAM-1 were measured in 27 high-risk trauma patients.

RESULTS

The IL-6 and IL-8 levels were significantly elevated in MOF patients compared with non-MOF patients at 12 and 36 hours postinjury. The IL-6 level was also elevated at 84 and 132 hours, and IL-8 at 84 hours. The sICAM-1 level did not become elevated in MOF patients until 132 hours postinjury.

CONCLUSIONS

Interleukin-6 and IL-8 are elevated early after trauma and discriminate patients who will develop MOF. Late elevation of sICAM-1 likely results from PMN cytotoxicity leading to EC injury or inflammation.

<em>Interleukin</em> (IL)-<em>27</em>, one of the most recently discovered IL-6 family cytokines, activates both the signal transducer and activator of transcription (STAT)1 and STAT3, and plays multiple roles in pro- and anti-inflammatory immune responses. IL-<em>27</em> acts on various types of cells including T, B, and macrophage through the common signal-transducing receptor gp130 and its specific receptor WSX-1, but the effect of IL-<em>27</em> on hematopoietic stem cells (HSCs) remains unknown. Here, we show that IL-<em>27</em> together with stem cell factor (SCF) directly acts on HSCs and supports their early differentiation in vitro and in vivo. CD34(-/low)c-Kit(+)Sca-1(+)lineage marker(-) (CD34(-)KSL) cells, a population highly enriched in mouse HSCs, were found to express both IL-<em>27</em> receptor subunits. In vitro cultures of CD34(-)KSL cells with IL-<em>27</em> and SCF resulted in an expansion of progenitors including short-term repopulating cells, while some of their long-term repopulating activity also was maintained. To examine its in vivo effect, transgenic mice expressing IL-<em>27</em> were generated. These mice exhibited enhanced myelopoiesis and impaired B lymphopoiesis in the bone marrow with extramedullary hematopoiesis in the spleen. Moreover, IL-<em>27</em> similarly acted on human CD34(+) cells. These results suggest that IL-<em>27</em> is one of the limited cytokines that play a role in HSC regulation.

Chronic obstructive pulmonary disease (COPD) is one of the leading causes of death. Although the underlying pathomechanism remains poorly understood, COPD is accompanied by increased cellular stress and inflammation. We investigated serum contents of heat shock proteins (HSP <em>27</em>, 60, 70, 90 alpha), 20S proteasomes, C-reactive protein (CRP), and <em>interleukin</em>-6 (IL-6) in patients with mild or severe COPD, healthy smokers and nonsmokers. HSP<em>27</em>, HSP70 and HSP90 alpha were significantly altered in patients suffering from COPD as compared to controls. HSP<em>27</em> and HSP70 are potential novel serum markers for the diagnosis of COPD in the smoking population. This is the first study to demonstrate elevated serum levels of the described heat shock proteins in patients with COPD. We showed sensitivity and specificity of serum HSP<em>27</em> and HSP70 as diagnostic markers for COPD.

Erythema migrans, the characteristic skin manifestation of acute Lyme borreliosis, is a self-limited lesion. In contrast, acrodermatitis chronica atrophicans, the typical cutaneous manifestation of late Lyme borreliosis, is a chronic skin condition. In an effort to understand pathogenic factors that lead to different outcomes in dermatoborrelioses, skin biopsy samples from 42 patients with erythema migrans and <em>27</em> patients with acrodermatitis chronica atrophicans were analyzed for mRNA expression of five pro-inflammatory cytokines (tumor necrosis factor alpha, <em>interleukin</em>-1 beta, <em>interleukin</em>-6, interferon-gamma, and <em>interleukin</em>-2) and two anti-inflammatory cytokines (<em>interleukin</em>-4 and <em>interleukin</em>-10) by in situ hybridization with cytokine-specific riboprobes. Among the <em>27</em> patients who had erythema migrans alone with no associated signs or symptoms, the major cytokines expressed in perivascular infiltrates of T cells and macrophages were the pro-inflammatory cytokine interferon-gamma and the anti-inflammatory cytokine <em>interleukin</em>-10. In the 15 erythema migrans patients who had associated signs and symptoms, including headache, elevated temperature, arthralgias, myalgias, or fatigue, a larger number of macrophages and greater expression of macrophage-derived pro-inflammatory cytokines, tumor necrosis factor alpha, <em>interleukin</em>-1 beta, and <em>interleukin</em>-6, were also found. In comparison, infiltrates of T cells and macrophages in the skin lesions of acrodermatitis chronica atrophicans patients had very little or no interferon-gamma expression. Instead, they usually expressed only the pro-inflammatory cytokine tumor necrosis factor alpha and the anti-inflammatory cytokine <em>interleukin</em>-4. Thus, the activation of pro-inflammatory cytokines in erythema migrans lesions, particularly interferon-gamma, seems to be important in the control of the spirochetal infection. In contrast, the restricted pattern of cytokine expression in acrodermatitis chronica atrophicans, including the lack of interferon-gamma, may be less effective in spirochetal killing, resulting in the chronicity of this skin lesion. J Invest Dermatol 115:1115-1123 2000

In susceptible individuals, the adaptive response, mediated by the activation of antigen-specific T lymphocytes, drives a proinflammatory response, which ends in an immune-mediated enteropathy characterized by villous atrophy, crypt hyperplasia, and recruitment of intraepithelial lymphocytes. In addition, some gluten peptides are able to induce an innate immune response in intestinal mucosa. The molecular mechanisms and the cells involved in the initial stages of the gluten-intestinal mucosa interaction are poorly understood to date. There is evidence of a direct toxic effect of gluten peptides in several biological models. However, the failure to control the inflammatory response may be one of the factors underlying gluten intolerance in these individuals. The cytokine network involved in celiac disease is characterized by abundant interferon-gamma in the intestinal mucosa. In addition, the production of <em>interleukin</em> (IL)-15, IL-18, and IL-21 is linked to gluten intake, which can drive the inflammatory response probably sustained by IL-18, IL-21, and perhaps IL-<em>27</em> through STAT1 and STAT5 pathways, whereas neither IL-12 nor IL-23 plays a significant role in pathogenic mechanisms. Herein we describe the involvement of these activation pathways in the context of the pathogenesis of celiac disease.

OBJECTIVE

To characterize the changes in retinal gene expression induced by elevated intraocular pressure (IOP) in a hereditary rodent model.

METHODS

A rat model derived from the RCS-rdy- strain develops IOP elevation spontaneously without experimental manipulation. Retinal gene expression after IOP elevation was compared with age-matched RCS-rdy- retinas having normal IOP levels The MWG Rat 10k array, which comprises 9715 rat genes spotted onto one array was used. Quantitative real-time PCR (qRT-PCR) was used to verify the expression of heat shock protein-<em>27</em> (Hsp-<em>27</em>), SA hypertension-associated gene, c-myc, tissue inhibitor of matrix metalloproteinase-1 (TIMP-1), vascular endothelial growth factor (VEGF), myocilin, <em>interleukin</em>-7 (IL-7), mitogen activated protein kinase 13 (MAPK-13) and crystallin beta-A1 (Cryba1). The cellular distribution of c-myc, glial fibrillary acidic protein (GFAP), VEGF, and SA was assessed using immunohistochemistry.

RESULTS

Elevated IOP of 37.7+/-5.0 mmHg shifted the retina's program of gene expression, with 75 genes being upregulated (equal to or higher than 3.0 fold) and 45 genes being downregulated (equal to or lower than 0.3 fold). These genes mediate various cellular processes such as cell adhesion, cell structure, hypertension, immunity, protein sythesis, proteolysis, transcription, and signaling. The regulation pattern of SA, VEGF, c-myc, IL-7, and MAPK-13, which are uniquely regulated in our model were confirmed by qRT-PCR experiments. The regulation of Hsp-<em>27</em>, TIMP-1, myocilin, and Cryba1, which have previously been associated with elevated IOP were also confirmed with qRT-PCR. The protein products of c-myc, SA, and GFAP were localized to astrocytes and Müller cells. Neurons in the ganglion cell layer and inner nuclear layer were VEGF-immunopositive.

CONCLUSIONS

This study identified some of the genes that are differentially regulated, probably in response to long-term IOP exposure, in this animal model. The expression pattern of many genes is common to experimental models of elevated IOP and other retinal disorders such as diabetic retinopathy. However many genes are uniquely expressed in the retina of our model. This suggests that the mode of IOP elevation be it experimental or spontaneous could be relevant in determining which genes are regulated. Müller glia acquire a reactive phenotype as indicated by the upregulation of GFAP, c-myc, SA, and other Müller cell markers, emphasizing their relevance in pressure related- and other types of retinal injury. These data provide further evidence that IOP-mediated retinal injury is multifactorial and depends upon the interaction of different neuronal, glial, extracellular matrix, and vasogenic components.

Appropriate induction of a Th1 immune response is required for effective antimicrobial immunity. However, dysregulated Th1 immune responses after infection may also lead to immunopathology. Thus, cell-mediated immune responses have to be tightly regulated. Upon infection, the production of <em>interleukin</em> (IL)-12, a heterodimeric cytokine composed of a p35 and a p40 subunit, is the dominant factor in Th1 cell development. The recent discovery of novel dimeric cytokines closely related to IL-12 add now to our understanding of cellular immunity and the fine tuning of T cell responses. At the onset of infection, IL-<em>27</em>, a heterodimer composed of the IL-12p40-related protein EBI-3 (Epstein-Barr virus-induced gene 3) and the IL-12p35-related protein p28 induces the expression of a functional IL-12 receptor in naive CD4+ T cells, making these cells sensitive to IL-12-mediated Th cell development. Later during infection, IL-23, a heterodimer composed of the IL-12p40 subunit and the IL-12p35-related molecule p19, preferentially acts on Th1 effector/memory CD4+ T cells. The IL-12p40 subunit can also form a homodimer, IL-12p80, which act as an IL-12 and IL-23 antagonist by competing at their receptors. This review focuses on these IL-12-related cytokines contributing to fine tuning of T cell responses after infection with intracellular pathogens.

BACKGROUND

In obese children, subclinical inflammation is often present and is correlated with the metabolic syndrome. Dietary factors, such as fatty acids and antioxidants, potentially modulate the association between adiposity and subclinical inflammation, but few data are available in children.

OBJECTIVE

The aim of the study was to determine whether dietary fat or antioxidant intakes influence circulating tumor necrosis factor alpha (TNF-alpha), interleukin 6 (IL-6), C-reactive protein (CRP), and leptin concentrations in overweight children.

METHODS

In a cross-sectional study of 6-14-y-old normal-weight (n = 33), overweight (n = 19), and obese (n = 27) Swiss children, nutritional intakes were assessed from two 24-h dietary recalls and a 1-d dietary record. Percentage body fat from skinfold thicknesses, waist-hip ratio, and blood pressure were measured. Fasting blood samples were collected for the measurement of insulin, glucose, HDL-cholesterol, triacylglycerol, CRP, IL-6, TNF-alpha, and leptin concentrations.

RESULTS

CRP, IL-6, and leptin increased significantly (P < 0.02) with increasing adiposity, independent of age; TNF-alpha did not increase. Total dietary fat and the percentage of energy from fat were significant predictors of CRP concentration, independent of body mass index (P < 0.05). Meat intake was a significant predictor of IL-6 and leptin, independent of body mass index (P < 0.05). Intakes of antioxidant vitamins (vitamins E and C and beta-carotene) were significant predictors of leptin (P < 0.05) but not of CRP, IL-6, or TNF-alpha.

CONCLUSIONS

Overweight Swiss children as young as 6 y have elevated concentrations of inflammatory markers. Intakes of total fat and antioxidant vitamins are determinants of subclinical inflammation in this age group.

The phenotype of mitogen-activated protein kinase-activated protein kinase-2 (MK2) knockout mice revealed the essential role of this enzyme in post-transcriptional regulation of lipopolysaccharide-induced expression of cytokines such as tumour necrosis factor (TNF)-alpha, <em>interleukin</em>-6 and interferon-gamma, at the level of mRNA stability and translation. In the case of TNF-alpha, this regulation depends on the AU-rich element in TNF-alpha mRNA. In addition to cytokine expression, MK2 is also essential for cell migration in vitro. Although the role of MK2 in cytokine expression depends mainly on catalytic activity, its role in cell migration is also dependent on a proline-rich N-terminal motif. However, the molecular mechanisms involved and the relevant protein targets for MK2 are not completely defined. Here we discuss the possible mechanisms by which two potential target proteins of MK2, small heat-shock protein 25/<em>27</em> (Hsp25/<em>27</em>) and tristetraprolin, could contribute to our understanding of the above regulation.

BACKGROUND

Recent evidence suggests that intestinal dysfunction has a role in sustaining the systemic inflammatory response in acute pancreatitis and may be ameliorated by the introduction of enteral nutrition. This study therefore assessed the effect of early enteral nutrition on the systemic inflammatory response in patients with prognostically severe acute pancreatitis.

METHODS

Patients with prognostically severe acute pancreatitis within 72 h of disease onset were randomized to receive either enteral nutrition or conventional therapy consisting of a nil-by-mouth regimen. Serum interleukin (IL) 6, soluble tumour necrosis factor receptor I (sTNFRI) and C-reactive protein (CRP) were used as markers of the inflammatory response. Intestinal function was assessed using a differential sugar permeability technique.

RESULTS

Of 27 patients, 13 received enteral nutrition. A median of 21 (range 0-100) per cent of calorific requirements was delivered over the first 4 days by enteral nutrition. There were no significant complications of enteral nutrition. The introduction of enteral nutrition did not affect the serum concentrations of IL-6 (P = 0.28), sTNFRI (P = 0.53) or CRP (P = 0.62) over the first 4 days of the study. Although there were no significant differences in intestinal permeability between the two patient groups at admission (chi2 = 2.33, d.f. = 1, P = 0.13), by day 4 abnormal intestinal permeability occurred more frequently in patients receiving enteral nutrition (chi2 = 4.94, d.f. = 1, P = 0.03)

CONCLUSIONS

Early enteral nutrition did not ameliorate the inflammatory response in patients with prognostically severe acute pancreatitis. Furthermore, it did not have a beneficial effect on intestinal permeability. Presented in part to the Pancreatic Society of Great Britain and Ireland in Leeds, UK, November 1998 and at Digestive Disease Week in Orlando, Florida, USA, May 1999

OBJECTIVE

To investigate the T-helper cell cytokine profiles in two well-defined clinical uveitis entities caused by an infectious mechanism.

METHODS

Cytokines (<em>interleukin</em> [IL]-2, IL-4, IL-6, IL-10, and interferon [IFN]-gamma) were measured in ocular fluid samples obtained from patients with herpes simplex- or varicella-zoster virus-induced acute retinal necrosis (ARN; n = 17) and toxoplasma chorioretinitis (n = <em>27</em>) using enzyme-linked immunosorbent assay techniques. The data were compared with data for 51 control samples taken during cataract surgery (n = 10), vitrectomy in diabetic retinopathy (n = 10), eye bank eyes (n = 10) and with samples from patients with "autoimmune" uveitis (n = 21).

RESULTS

Interleukin-6 was detected in 44 of 51 control samples and 43 of 44 eyes of patients with uveitis. The highest levels in the control samples were detected in 9 of 10 vitreous samples from patients with diabetic retinopathy (mean, 648 pg/ml). In 8 of 10 samples taken from patients during cataract surgery and in 7 of 10 eye bank eyes the amount of IL-6 was significantly lower (mean, 10 pg/ml and 136 pg/ml, respectively). Interleukin-6 levels in patients with ARN (mean, 1436 pg/ml) were significantly higher than in those with toxoplasma chorioretinitis (mean, <em>27</em>2 pg/ml). Interleukin-2 was detected in one of the samples from patients with toxoplasma chorioretinitis (1105 pg/ml) and in three samples from the control subjects suffering from Fuchs' heterochromic anterior uveitis (mean, 752 pg/ml). No IL-4 (<2 pg/ml) was detected either in patient or control samples. Interferon-gamma could be detected in 7 of 17 ARN patients (range, <em>27</em>7-3483 pg/ml), in 13 of <em>27</em> samples from patients with toxoplasma chorioretinitis (range, 12-250 pg/ml), and in 1 of 21 of the samples from control subjects with uveitis (31 pg/ml) but was absent in nonuveitic control samples. Interleukin-10 was detected in 10 of 17 ARN patients (range, 29-39<em>27</em> pg/ml), in 13 of <em>27</em> samples from patients with toxoplasma chorioretinitis (range, 4-67 pg/ml), and in only 3 of 51 control samples (6 pg/ml, 16 pg/ml, and 20 pg/ml).

CONCLUSIONS

Various immunoregulatory cytokines (IL-6, IL-10, and IFN-gamma) were detected in ocular fluid samples from patients with uveitis. A separate role for either a T-helper type 1 or T-helper type 2 response in the pathogenesis of clinical uveitis could not be proven.

OBJECTIVE

In 215 consecutive patients with advanced metastatic renal cell carcinoma seen at a single institution the efficacy and tolerance of different subcutaneous recombinant interleukin-2 based home therapies were assessed.

METHODS

Treatment consisted of subcutaneous recombinant interleukin-2 alone and subcutaneous recombinant interleukin-2 in combination with recombinant interferon-alpha 2 with or without intravenous 5-fluorouracil.

RESULTS

Overall objective response rate in 215 patients was 33% (95% confidence interval 26 to 39%). Among 16 patients receiving recombinant interleukin-2 alone there was 1 partial remission (overall response 6%). In 79 patients receiving recombinant interleukin-2 and interferon-alpha 2 in combination 6 complete and 16 partial remissions occurred (overall response 28%). Of 120 patients receiving a combination of recombinant interleukin-2, recombinant interferon-alpha 2 and 5-fluorouracil 13 achieved a complete and 34 a partial remission (overall response 39%). Of all patients 5% achieved long-lasting remissions and remain disease-free. Multivariate analyses identified pretreatment erythrocyte sedimentation rate greater than 70 mm. per hour and lactic dehydrogenase greater than 280 units per l. as independent prognostic factors of major significance (p < or = 0.0001) in metastatic renal cell carcinoma. Additionally, neutrophil count greater than 6,000/microliters., hemoglobin less than 100 gm./l., extrapulmonary metastases and bone lesions were identified as minor (p < or = 0.006) prognostic variables. Patients were assigned to 1 of 3 risk categories according to cumulative risk score defined as the function of the sum of all 6 independent variables. In 116 intermediate risk patients 2-year survival was 65% (median survival not reached after 32 months) with recombinant interleukin-2, recombinant interferon-alpha 2 and 5-fluorouracil, as opposed to 27% 2-year survival (median survival 15 months) with recombinant interleukin-2 and interferon-alpha 2 (p < 0.0001), and 0% (median survival 4.8 months) with single agent recombinant interleukin-2. In the majority of patients systemic toxicity of subcutaneous recombinant interleukin-2 based protocols was limited to grade 1 or 2 constitutional symptoms, that is fever, chills, malaise and anorexia, which allowed for outpatient therapy.

CONCLUSIONS

The present outpatient recombinant interleukin-2 triple drug combination protocol was as effective as the most aggressive intravenous recombinant interleukin-2 regimen available. Combination home therapy eliminated the need for inpatient and/or intensive care as required for intravenous cytokine administration and, thereby, it substantially improved the therapeutic index and cost-effectiveness of recombinant interleukin-2 therapy in metastatic renal cell carcinoma stratified for risk.

BACKGROUND

A precise role for the innate immune system in psoriasis remains to be determined. Surface receptors, including Toll-like receptors (TLRs) that recognize bacterial ligands and CD91, which recognizes heat shock proteins (HSPs), are implicated in both innate and adaptive immunity.

OBJECTIVE

Since skin is exposed to various exogenous stimuli, which can provoke or exacerbate psoriasis, we characterized expression and function of TLRs, CD91, and HSPs in normal and psoriatic skin.

METHODS

A variety of skin-derived cells and blood-derived cells were analyzed both in vivo and in vitro; samples were obtained from 24 different individuals for innate immune-related receptor expression and function. By comparing and contrasting individuals with healthy skin and psoriatic patients, several specific differences were identified.

RESULTS

Immunohistochemistry-based expression profiling revealed TLR1 expression in epidermal dendritic cells (DCs) and dermal dendritic cells (DDCs) in normal skin, as well as in pre-psoriatic skin and psoriatic plaques, with enhanced basal layer keratinocyte (KC) expression in pre-psoriatic and psoriatic plaques compared with normal skin; TLR2 expression primarily by DDCs; and TLR4 expression by epidermal DCs and DDCs, with mid-epidermal-layer KCs displaying cell surface staining. No TLR9 or CD14 was detected on DCs or KCs, although psoriatic plaques contained CD14-positive macrophages. Analysis of psoriatic epidermis revealed HSPs <em>27</em>, 60, and 70. Keratinocytes were CD91 negative, but CD91 was expressed by fibroblasts and DDCs in normal and pre-psoriatic skin, with prominent accumulation of CD91-positive DDCs in psoriatic plaques. Cultured KCs revealed no surface expression of TLR2, TLR4, TLR9, or CD91. Exposure of fibroblasts, but not KCs, to lipopolysaccharide or HSPs triggered nuclear factor (NF)-kappaB activation. Heat shock proteins did induce maturation of blood-derived DCs accompanied by increased <em>interleukin</em>-12 production and enhanced antigen-presenting function.

CONCLUSIONS

These data demonstrate distinctive patterns of innate immune-related receptors by specific subsets of cells in normal and psoriatic skin, suggesting functional roles for HSPs and DCs in psoriasis.

We measured plasma levels of <em>interleukin</em>-1 beta (IL-1 beta), tumor necrosis factor alpha (TNF alpha), and <em>interleukin</em>-6 (IL-6) following thermal injury. Cytokine levels in the plasma of <em>27</em> burned patients were serially screened by ELISA and compared with cytokine levels in 16 healthy laboratory employees. The relationships between cytokine concentrations and patient mortality, burn size, and time postburn were examined. Plasma samples with detectable amounts of IL-1 beta and IL-6 were significantly more frequent in burned patients than in controls, whereas TNF alpha was undetectable in most plasma samples. All nonsurviving burned patients had detectable IL-6 levels; these were significantly higher than those of surviving patients. The IL-1 beta and IL-6 concentrations were highest during the first week after injury and declined over time. The IL-1 beta concentrations were positively correlated with burn size. These findings suggest that IL-1 beta and IL-6 may influence metabolic and immunologic responses in the first few weeks following thermal injury. Tumor necrosis factor alpha was transiently elevated in a small subpopulation of burned patients with no obvious relationship to burn size or time postburn.

BACKGROUND

Methylation status of the cytokine genes may play a role in the pathogenesis of inflammatory diseases, such as rheumatoid arthritis (RA) and chronic periodontitis (CP). This study was undertaken to evaluate whether the DNA methylation profile of the interleukin-6 (IL-6) gene promoter was unique to individuals with RA and CP.

METHODS

The study participants consisted of 30 patients with RA, 30 patients with CP, and 30 age-, sex-, and smoking status-balanced healthy controls. Genomic DNA isolated from peripheral blood was modified by sodium bisulfite and analyzed for DNA methylation levels of IL-6 gene with direct sequencing. Levels of IL-6 were determined by an enzyme-linked immunosorbent assay.

RESULTS

The region of IL-6 gene promoter from -1200 to +27 bp was shown to contain 19 CpG motifs. The methylation levels of the CpG motif at -74 bp were significantly lower in patients with RA and CP than those in controls (P = 0.0001). Both levels of serum IL-6 and IL-6 production by mononuclear cells were significantly different between individuals with and without the methylation at -74 bp (P = 0.03). The +19 bp motif exhibited differential levels of the methylation among the groups, which was not associated with serum levels of IL-6. The other 17 CpG motifs exhibited comparable levels of the methylation between the groups.

CONCLUSIONS

These results suggest that hypomethylated status of a single CpG in the IL-6 promoter region may lead to increased levels of serum IL-6, implicating a role in the pathogenesis of RA and CP.

BACKGROUND

Neutrophil recruitment coordinated by intestinal interleukin (IL)-8 secretion is a key component in the pathogenesis of Clostridium difficile infection (CDI). We hypothesized that a common single-nucleotide polymorphism (SNP) in the -251 region of the IL-8 gene promoter may be predictive of recurrent CDI.

METHODS

This was a prospective cohort study of hospitalized adult patients with CDI who were admitted to a large, university-affiliated medical center from 2007 through 2008. Patients were monitored for 3 months after diagnosis of CDI and assessed for recurrent CDI (defined as a return of diarrhea that required treatment after initial symptom resolution). DNA was isolated from blood samples, and genetic sequencing was performed using polymerase chain reaction and pyrosequencing. The association between IL-8 genotype and recurrent CDI was assessed using univariate and multivariate statistics.

RESULTS

Ninety-six patients with a mean (± standard deviation) age of 61 ± 16 years (54% of whom were female and 63% of whom were white) were identified. The overall incidence of recurrent CDI was 24%. IL-8 allele frequency was similar to previously reported findings (for A/A, 27%; for A/T, 53%; and for T/T, 20%). The incidence of recurrent CDI was 38% in patients with the A/A allele and 19% in all other patients (relative risk, 2.1; 95% confidence interval, 1.04-4.13) (P = .043).

CONCLUSIONS

This study indicates that a common SNP in the IL-8 gene promoter is an independent predictor of recurrent CDI. Our results could offer risk stratification for patients at high risk for recurrent CDI.

Pulmonary fibrosis develops in Hermansky-Pudlak syndrome (HPS) types 1 and 4. Limited information is available about lung disease in HPS type 2 (HPS-2), which is characterized by abnormal function of the adaptor protein-3 (AP-3) complex. To define lung disease in HPS-2, one child and two adults with HPS-2 were evaluated at the National Institutes of Health on at least two visits, and another child was evaluated at the University of Texas Health Science Center San Antonio. All four subjects with HPS-2 had findings of interstitial lung disease (ILD) on a high-resolution computed tomography scan of the chest. The predominant feature was ground glass opacification. Subject 1, a 14-year-old male, and subject 4, a 4-year-old male, had severe ILD, pulmonary fibrosis, secondary pulmonary hypertension and recurrent lung infections. Lung biopsy performed at 20 months of age in subject 1 revealed interstitial fibrosis and prominent type II pneumocyte hyperplasia without lamellar body enlargement. Subject 2, a <em>27</em>-year-old male smoker, had mild ILD. Subject 3, a 22-year-old male nonsmoker and brother of subject 2, had minimal ILD. Severe impairment of gas exchange was found in subjects 1 and 4 and not in subjects 2 or 3. Plasma concentrations of transforming growth factor-β1 and <em>interleukin</em>-17A correlated with severity of HPS-2 ILD. These data show that children and young adults with HPS-2 and functional defects of the AP-3 complex are at risk for ILD and pulmonary fibrosis.

Currently, there are no established biomarkers for diagnosing preclinical vasospasm or monitoring its progression. Two areas of extensive biomarker research are neuroimaging and biochemical markers in body fluids, such as cerebrospinal fluid (CSF). We performed a review of studies conducted over the past 2 decades summarizing the science to date and the evolution of CSF biomarkers in subarachnoid hemorrhage (SAH). A Medline search performed using the search terms "subarachnoid hemorrhage marker AND cerebrospinal fluid," limited to the period January 1, 1990 to June 1, 2009, returned 62 references. Abstracts that did not deal primarily with SAH and potential markers in the CSF of humans were excluded, resulting in <em>27</em> abstracts. Only articles providing sufficient information for a substantiated analysis were selected. In addition, articles identified in reference lists of individual articles were selected if considered appropriate. Evidence was classified as class I-IV and recommendations were classified as category A-C according to European Federation of Neurological Societies guidelines. We evaluated CSF markers in SAH patients and divided them into 3 categories: A, markers with auspicious value; B, candidate markers; and C, noncandidate markers. Category A markers included tumor necrosis factor (TNF)-α, soluble tumor necrosis factor receptor I (sTNFR-I), and <em>interleukin</em> (IL)-1 receptor antagonist (IL-1ra), as well as the neurofilament proteins NFL and NfH. Category B markers included apolipoprotein E (ApoE), F2-isoprostane (F2-IsoP), NOx, and the indicators for thrombin activity membrane-bound tissue factor (mTF) and thrombin-antithrombin III complex (TAT) for neurologic outcome prediction, as well as E-selectin, lactate, alpha-II spectrin breakdown products (SBDPs), asymmetric dimethyl-L-arginine (ADMA), and monocyte chemoattractant protein-1 (MCP-1) for vasospasm prognostication. Category C markers included S100B, platelet-derived growth factor (PDGF), YKL-40, chitotriosidase, intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and IL-8. Cytokines and their receptors, as well as neuronal intracellular proteins, seem to be potential markers for outcome determination in patients after SAH.

BACKGROUND

Severe acute pancreatitis (AP) is associated with high morbidity and mortality. Early prediction of severe AP is needed to improve patient outcomes. The aim of the present study was to find novel cytokines or combinations of cytokines that can be used for the early identification of patients with AP at risk for severe disease.

METHODS

We performed a prospective study of 163 nonconsecutive patients with AP, of whom 25 had severe AP according to the revised Atlanta criteria. Admission serum levels of 48 cytokines and growth factors were determined using Bio-Plex Pro Human Cytokine Assay 21-plex and <em>27</em>-plex magnetic bead suspension panels. Admission plasma levels of C-reactive protein (CRP), creatinine and calcium were measured for comparison. In subgroup analyses, we assessed the cytokine profiles of patients with severe AP (n = 14) who did not have organ dysfunction (OD) upon admission (modified Marshall score <2).

RESULTS

Of 14 cytokines elevated in the severe AP group, interleukin 6 (IL-6) and hepatocyte growth factor (HGF) levels were independent prognostic markers of severe AP. IL-6, HGF and a combination of them predicted severe AP with sensitivities of 56.0%, 60.0% and 72.0%, respectively, and specificities of 90.6%, 92.8% and 89.9%, respectively. The corresponding positive likelihood ratio (LR+) values were 5.9, 8.3 and 7.1, respectively. The predictive values of CRP, creatinine and calcium were comparable to those of the cytokines. In subgroup analyses of patients with severe AP and without OD upon admission, we found that IL-8, HGF and granulocyte colony-stimulating factor (G-CSF) levels predicted the development of severe AP, with G-CSF being the most accurate cytokine at a sensitivity of 35.7%, a specificity of 96.1% and a LR+ of 9.1.

CONCLUSIONS

IL-6 and HGF levels upon admission have prognostic value for severe AP which is similar to levels of CRP, creatinine and calcium. Although IL-6 and HGF, as either single or combined markers, were not perfect in identifying patients at risk for severe AP, the possibility that combining them with novel prognostic markers other than cytokines might improve prognostic accuracy needs to be studied. The accuracy of IL-8, HGF and G-CSF levels in predicting severe AP in patients without clinical signs of OD upon admission warrants larger studies.

The outcome of chronic viral infections, which affect millions of people worldwide, is greatly dependent on CD4⁺ T cells. Here we showed that T cell-specific ablation of the common <em>interleukin</em>-6 (IL-6) family receptor, gp130, profoundly compromised virus-specific CD4⁺ T cell survival, T follicular helper responses, and IL-21 production at late stages of chronic lymphocytic choriomeningitis virus (LCMV) infection. These effects were cell intrinsic for CD4⁺ T cells and were accompanied by a reduction of CD8⁺ T cells, antibodies, and a severe failure in viral control. We identified IL-<em>27</em> as a gp130 cytokine that promoted antiviral CD4⁺ T cell accumulation in vivo and that rapidly induced IL-21 ex vivo. Furthermore, IL-<em>27</em>R was critical for control of persistent LCMV in vivo. These results reveal that gp130 cytokines (particularly IL-<em>27</em>) are key regulators of CD4⁺ T cell responses during an established chronic viral infection, empowering both humoral and cytotoxic immunity.

BACKGROUND

Human periodontal diseases are inflammatory disorders that are the result of complex interactions between periodontopathogens and the host's immune response. Two important and interrelated factors are involved in the pathophysiological progression of periodontal diseases, i.e. the activation of immune system and the production of oxygen radicals and their related metabolites. Increased production of oxygen radicals may contribute to oxidative stress, which is reported to be involved in many diseases, including periodontal diseases.

OBJECTIVE

The objective of this study was to investigate glutathione peroxidase, lactoferrin and myeloperoxidase, which play an essential role in free radical production and defenses, and the proinflammatory cytokine interleukin-1beta (IL-1beta), which is important in the regulation of immunological and inflammatory reactions in human periodontal diseases.

METHODS

Gingival crevicular fluid (GCF) samples were collected from 27 subjects, 19 periodontitis patients and eight healthy controls, ranging in ages from 24 to 62 years. Clinical parameters were recorded. GCF glutathione peroxidase, lactoferrin, myeloperoxidase and IL-1beta were analyzed by enzyme-linked immunosorbent assays (ELISA).

RESULTS

The periodontitis sites exhibited significantly greater total amount of glutathione peroxidase, lactoferrin, myeloperoxidase and IL-1beta than healthy sites. Total amount of glutathione peroxidase, lactoferrin, myeloperoxidase and IL-1beta was positively correlated with plaque index, gingival index, probing depth and probing attachment level (p < 0.05).

CONCLUSIONS

The imbalance between the levels of myeloperoxidase/IL-1beta and glutathione peroxidase/lactoferrin could result in tissue damage of reactive oxygen species (ROS) in periodontitis which is initiated and perpetuated by the chronic insults of periodontopathogens.

The ability of CD4+ T cells from CBA/Rij mice to produce <em>interleukin</em> (IL) 2 after stimulation with anti-CD3, concanavalin A, or the combination of phorbol 12-myristate 13-acetate and ionomycin declines during aging. This phenomenon was accompanied by an increased production of IL 4 and interferon-gamma. These age-related changes in lymphokine production correlated with the decrease in the percentage of CD45RBhi CD4+ T cells from about 80% in 2-month-old to about 40% in <em>27</em>-month-old mice. This phenotypic shift was responsible for the decline in IL 2 production, because in young and in old mice CD45RBhi CD4+ T cells were more potent IL 2 producers than CD45RBlo cells. Moreover, old CD45RBhi CD4+ T cells produced less IL 2 than their young counterparts. Proliferative responses by T cells from old mice were lower than those of young mice, regardless whether the cultures were supplemented with IL 2, IL 4 or both lymphokines. As far as CD4+ T cells were concerned, this hyporesponsiveness was found in the CD45RBlo as well as in the CD45RBhi CD4+ T cell population.

Aspergillus fumigatus is the most prevalent airborne fungal pathogen and causes fatal invasive aspergillosis in immunocompromised patients. Given the essential role of dendritic cells (DC) in initiating and regulating immune responses, we investigated the impact of A. fumigatus conidial infection on human DC. A. fumigatus conidia were rapidly internalized and induced the release of tumor necrosis factor alpha within the first 8 h. After A. fumigatus infection, the majority of DC underwent full maturation, although CCR7 expression was observed only in DC that had internalized the conidia. Additionally, the analysis of regulatory cytokines showed that infected DC simultaneously produced <em>interleukin</em>-12p70 (IL-12p70) and significant amounts of IL-10. IL-10 neutralization was not able to further increase IL-12p70 production from infected DC. Whereas the central role of IL-12 in the generation of Th1 cells has long been appreciated, recently two other members of the IL-12 family, IL-23 and IL-<em>27</em>, were reported to play important roles in the regulation of gamma interferon (IFN-gamma) production from naïve and memory T cells. A. fumigatus-infected DC were also able to express high levels of IL-23p19 and low levels of IL-<em>27</em>p28 at later stages of infection. According to this expression pattern, A. fumigatus-infected DC were able to prime IFN-gamma production of naïve T cells. Thus, this study on the expression of the new IL-12 family members controlling the Th1 response sheds light on a novel aspect of the contribution of DC to anti-Aspergillus immunity.

<em>Interleukin</em> (IL)-6, a key player in the inflammatory response, may be a useful biomarker in rheumatoid arthritis (RA). The aim was to determine analytical variability, a reference interval in healthy subjects, and long- and short-term variation in serum and plasma IL-6 in healthy subjects and RA patients. An enzyme-linked immunosorbent assay from R&D was used for determination of serum and plasma IL-6. The IL-6 concentration did not depend on the type of anticoagulant used or the 3-h time delay between sampling and processing or repeated freeze-thaw cycles. The median plasma and serum IL-6 in 318 healthy subjects were 1.3 pg ml(-1) (range 0.33-26) and 1.4 pg ml(-1) (range 0.25-23), respectively. The median coefficient of variation in plasma IL-6 in <em>27</em> healthy subjects during 1 month, and repeated after 6 and 12 months were <em>27</em>%, 31% and 26%, respectively. No significant long-term changes were observed in serum IL-6 over a 3-year period (14%, p = 0.33). Exercise (cycling) increased serum IL-6 in healthy subjects but not in RA patients. In conclusion, circulating IL-6 is stable regarding sample handling and shows little variation over time. Changes in IL-6 concentrations>> 60% (2 times the biological variation) are likely to reflect changes in disease activity and not only pre-analytical or normal biological variability.