Serum and CSF levels of soluble intercellular adhesion molecule-1 (ICAM-1) in inflammatory neurologic diseases

Predictive value of plasma sICAM-1 and sP-Selectins in the risk of death in patients with acute respiratory distress syndrome

Background

To evaluate the predictive value of sICAM-1 and sP-Selectins in the risk of death in a prospective cohort of adult acute respiratory distress syndrome (ARDS).

Methods

Adult ARDS patients were included. Plasma sICAM-1, sP-Selectins, and inflammatory cytokines (TNF-α, IL-1b, IL-6, IL-8, and IL-17A) were detected in ARDS subjects. The correlation between different factors and the potential of sICAM-1 and sP-Selectins as endothelial markers to predict the risk of deathfrom ARDS was analyzed.

Elevated Blood and Urinary ICAM-1 is a Biomarker for Systemic Lupus Erythematosus: A Systematic Review and Meta-Analysis

Background: Systemic lupus erythematosus (SLE) is an autoimmune disease with complex etiology. Intercellular cell adhesion molecule-1 (ICAM-1) is critical for leukocyte adhesion to endothelium and migration out of blood vessels and thus participates in many autoimmune diseases. Previous studies of blood and urinary ICAM-1 in SLE have yielded inconsistent results.Methods: The following databases were searched for studies that compared blood and/or urinary ICAM-1 in SLE patients vs. healthy control subjects, and/or in SLE with active vs. inactive diseases: PubMed, EMBASE, Cochrane Library, China National Knowledge Infrastructure and Web of Science. Standardized mean difference (SMD) and 95% confidence intervals (CI) were calculated using a random-effects model when there was significant heterogeneity (assesses using the Cochrane Q test and I² statistics), and using a fixed-effects model otherwise. Publication bias was assessed using funnel plot and egger text.Results: The initial screening yielded a total of 1,215 articles; 22 articles (14 reporting blood ICAM-1, 7 reporting urinary ICAM-1 and 1 reporting both) were included in the meta-analysis. In comparison to healthy controls, SLE patients had elevated urinary ICAM-1 (SMD: 0.711; 95% CI: 0.521, 0.901) as well as blood ICAM-1 (SMD: 0.725; 95% CI: 0.385, 1.065). Blood ICAM-1 did not differ significantly between active and inactive SLE (SMD: 0.396; 95% CI: -0.556, 1.347).Conclusion: Elevated blood and urinary ICAM-1 is a biomarker for SLE, but does not differentiate active and inactive SLE.

Transcriptome-wide N 6 -methyladenosine methylome profiling of porcine muscle and adipose tissues reveals a potential mechanism for transcriptional regulation and differential methylation pattern

Background

N⁶-methyladenosine (m⁶A) is the most prevalent internal form of modification in messenger RNA in higher eukaryotes and potential regulatory functions of reversible m⁶A methylation on mRNA have been revealed by mapping of m⁶A methylomes in several species. m⁶A modification in active gene regulation manifests itself as altered methylation profiles in a tissue-specific manner or in response to changing cellular or species living environment. However, up to date, there has no data on m⁶A porcine transcriptome-wide map and its potential biological roles in adipose deposition and muscle growth.

Methods

In this work, we used methylated RNA immunoprecipitation with next-generation sequencing (MeRIP-Seq) technique to acquire the first ever m⁶A porcine transcriptome-wide map. Transcriptomes of muscle and adipose tissues from three different pig breeds, the wild boar, Landrace, and Rongchang pig, were used to generate these maps.

Results

Our findings show that there were 5,872 and 2,826 m⁶A peaks respectively, in the porcine muscle and adipose tissue transcriptomes. Stop codons, 3′-untranslated regions, and coding regions were found to be mainly enriched for m⁶A peaks. Gene ontology analysis revealed that common m⁶A peaks in nuclear genes are associated with transcriptional factors, suggestive of a relationship between m⁶A mRNA methylation and nuclear genome transcription. Some genes showed tissue- and breed-differential methylation, and have novel biological functions. We also found a relationship between the m⁶A methylation extent and the transcript level, suggesting a regulatory role for m⁶A in gene expression.

Conclusion

This comprehensive map provides a solid basis for the determination of potential functional roles for RNA m⁶A modification in adipose deposition and muscle growth.

Electronic supplementary material

The online version of this article (doi:10.1186/s12864-017-3719-1) contains supplementary material, which is available to authorized users.

Plasma levels of soluble intercellular adhesion molecule-1 as a biomarker for disease severity of patients with community-acquired pneumonia

BACKGROUND

Community-acquired pneumonia (CAP) is characterized as an acute inflammation of the lung associated with the activation of macrophages and neutrophils. Intercellular adhesion molecule-1 (ICAM-1) is an essential adhesion molecule involved in immune cell recruitment in lung inflammation. We investigated whether ICAM-1 is a useful biomarker for assessing the disease severity of hospitalized adult patients with CAP.

METHODS

Plasma soluble ICAM-1 (sICAM-1) levels were measured in 78 patients with CAP and 69 healthy controls by using a commercial enzyme-linked immunosorbent assay. The pneumonia severity index scores were used to determine CAP severity in patients upon initial hospitalization.

RESULTS

The sICAM-1 and C-reactive protein (CRP) levels decreased significantly in patients with CAP after antibiotic treatment. The plasma concentration of sICAM-1 alone, but not CRP, was correlated with CAP severity according to the pneumonia severity index scores (r=0.431, p<0.001). The sICAM-1 levels in patients with CAP with high mortality risk were significantly higher than those in patients with CAP with medium or low mortality risk. Moreover, the sICAM-1 level showed a significant correlation with the length of hospital stay (r=0.488, p<0.001). Mechanistic investigations found that bacterial lipopolysaccharide induced upregulation of ICAM-1 expression through the c-Jun N-terminal kinase pathway in RAW264.7 macrophages.

CONCLUSIONS

Plasma sICAM-1 levels may play a role in the diagnosis and clinical assessment of CAP severity.

A new approach to ELISA-based anti-glycolipid antibody evaluation of highly adhesive serum samples

The enzyme-linked immunosorbent assay (ELISA) is a standard immunoassay used in measuring antibody reactivity (expressed as titers) for glycosphingolipids (GSLs) such as gangliosides and sulfoglycolipids in the sera of patients with Guillain-Barré syndrome (GBS), variants of GBS, and chronic inflammatory demyelinating polyneuropathy (CIDP). In the present study, anti-GSL antibodies were evaluated using a new formula of affinity parametric complex (APC), calculated from limiting-dilution serum assay data, followed by affinity parametric complex criterion (APCC). Using assay results based on APCC, we analyzed serum samples categorized into acute inflammatory demyelinating polyneuropathy (AIDP), acute motor-sensory axonal neuropathy (AMSAN), CIDP, CIDP with myasthenia gravis (MG), and amyotrophic lateral sclerosis (ALS). We were able to determine the affinity strength of antibodies otherwise hidden in the non-specific background activity in highly adhesive serum samples. The thin-layer chromatography (TLC)-immuno-overlay method assured us that this new method is an accurate and reliable way for evaluating anti-GSL antibodies using ELISA serum sample data.

Identification of gene networks and pathways associated with Guillain-Barré syndrome

BACKGROUND

The underlying change of gene network expression of Guillain-Barré syndrome (GBS) remains elusive. We sought to identify GBS-associated gene networks and signaling pathways by analyzing the transcriptional profile of leukocytes in the patients with GBS.

METHODS AND FINDINGS

Quantitative global gene expression microarray analysis of peripheral blood leukocytes was performed on 7 patients with GBS and 7 healthy controls. Gene expression profiles were compared between patients and controls after standardization. The set of genes that significantly correlated with GBS was further analyzed by Ingenuity Pathways Analyses. 256 genes and 18 gene networks were significantly associated with GBS (fold change ≥2, P<0.05). FOS, PTGS2, HMGB2 and MMP9 are the top four of 246 significantly up-regulated genes. The most significant disease and altered biological function genes associated with GBS were those involved in inflammatory response, infectious disease, and respiratory disease. Cell death, cellular development and cellular movement were the top significant molecular and cellular functions involved in GBS. Hematological system development and function, immune cell trafficking and organismal survival were the most significant GBS-associated function in physiological development and system category. Several hub genes, such as MMP9, PTGS2 and CREB1 were identified in the associated gene networks. Canonical pathway analysis showed that GnRH, corticotrophin-releasing hormone and ERK/MAPK signaling were the most significant pathways in the up-regulated gene set in GBS.

CONCLUSIONS

This study reveals the gene networks and canonical pathways associated with GBS. These data provide not only networks between the genes for understanding the pathogenic properties of GBS but also map significant pathways for the future development of novel therapeutic strategies.

Procalcitonin, C-reactive protein, interleukin-6, and soluble intercellular adhesion molecule-1 as markers of postoperative orthopaedic joint prosthesis infections

There is a universally recognized need to identify new, reliable markers of inflammation that can aid in the rapid diagnosis of orthopaedic joint prosthesis infections (OJP-Is). Since prompt diagnosis is key to timely intervention in the course of infection, different molecules have been studied. In this study, we examined three groups of patients: those with prosthesis infection, those without infection, and a third group with previous infection in whom the infection had been cleared. Four presumed markers of infection were tested: procalcitonin (PCT); C-reactive protein (CRP); interleukin-6 (IL-6); and soluble intercellular adhesion molecule-1 (sICAM-1). The results showed that PCT cannot be considered as a good marker of periprosthetic infection as no statistically significant difference in serum PCT levels emerged between patients with infection and controls or patients without infection. In contrast, both sICAM-1 and CRP may be considered as good markers of infection, as measurement of their levels allowed us to distinguish between patients with and without infection, and between patients with infection and those with previous infection, since marker levels quickly returned to baseline values after clearance of the infection. IL-6 was found to be a good marker for inflammation, as it distinguished between patients with infection and the other groups. In the patients with previous infection, the IL-6 values remained high versus the controls but lower and with a statistically significant difference versus the patients with infection. Further studies are needed to determine the cut-off value of IL-6 between patients with infection and those with previous infection.

Adhesion molecule levels in serum and cerebrospinal fluid in children with bacterial meningitis and sepsis

BACKGROUND

Adhesion molecules play a role in leukocyte recruitment during central nervous system (CNS) inflammation.

AIM

This study was designed to compare serum, cerebrospinal fluid (CSF) concentrations of adhesion molecules in children with meningitis and sepsis, and to evaluate their sources.

SETTING

This study was carried out at Pediatric Department, King Abdulaziz University Hospital from January 2007 to June 2008.

DESIGN

Serum and CSF samples were collected on admission from meningitis (n = 40), sepsis (n = 20) patients, and sera from controls (n = 20).

MATERIALS AND METHODS

Endothelial (E), leukocyte (L), platelet (P) selectins intercellular cell adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecules-1 (VCAM-1) were measured using ELISA.

STATISTICS

ANOVA and Spearman's correlations were used. Adhesion molecules with albumin concentration were estimated in CSF/serum to calculate concentration quotients.

RESULTS

In meningitis, serum sE-, sL-, sP-selectins sICAM-1, sVCAM-1 levels were higher than controls. Compared to sepsis, serum sE-selectin, sL-selectin, sVCAM-1, CSF-sL-selectin, CSF-sVCAM-1, VCAM-1 ratio and index were higher, while serum sP-selectin was lower than meningitis. sE-selectin ratio, CSF sICAM-1 were higher in meningitis with positive than negative culture. The sE-selectin index was higher in meningitis with neurological complication than those without it. In meningitis, correlation was found between CSF protein and CSF white blood cell counts (WBCs), CSF sICAM-1, CSF sVCAM-1 and between CSF sE-selectin and CSF sICAM-1.

CONCLUSIONS

This study supports the role of adhesion molecules especially sL-selectin, sVCAM-1 in meningitis and suggests further research to determine their use as biomarkers for meningitis and use of their antagonists as therapeutic for CNS inflammation. The presence of discrepancy of CSF/serum ratios for molecules of same molecular weight suggest intrathecal shedding in addition to diffusion through the blood-CSF barrier.

Increase in Adhesion Molecules in Cerebrospinal Fluid of Children with Mumps and Mumps Meningitis

Adhesion molecules play a key role in leucocyte migration into the central nervous system (CNS). Concentrations of endothelial-derived soluble intercellular adhesion molecule-1 (sICAM-1) and leucocyte-originated soluble L-selectin (sL-selectin) in cerebrospinal fluid (CSF) of children with mumps meningitis (mononuclear pleocytosis, n = 33) and mumps (absence of pleocytosis, n = 9) were compared with values from age-matched control group (n = 19). In 14 patients from the meningitis group, adhesion molecule levels together with albumin concentration were estimated in paired CSF/serum samples to calculate concentration quotients and determine molecule intrathecal release. Both sICAM-1 (median 3.44 versus 0.86 ng/ml; P < 0.0001) and sL-selectin (median 29.91 versus 8.52 ng/ml; P < 0.0001) concentrations in CSF were increased in mumps meningitis patients compared with controls. Increased levels of the selected adhesion molecules were also observed in mumps patients without CNS involvement when compared with controls (median sICAM-1: 1.14 versus 0.86 ng/ml, sL-selectin: 13.54 versus 8.52 ng/ml; P < 0.01). Additionally, the concentration of adhesion molecules was found to correlate with CSF leucocyte count. Considerable correlation of sICAM-1 and sL-selectin quotients and corresponding albumin quotients suggests that a majority of the soluble adhesion molecules originated from the bloodstream. Analysis of adhesion molecule levels demonstrated indirect evidence of brain-derived fractions. Our results suggest the involvement of adhesion molecules during the early phase of mumps meningitis.

sICAM-1 in meningoencephalitis due to Angiostrongylus cantonensis

INTRODUCTION: Angiostrongylus cantonensis meningoencephalitis is an emergent disease in the Americas. METHOD: Twelve children suffering from eosinophilic meningoencephalitis due to this parasite aged between 6-10 years were studied. Cerebrospinal fluid (CSF) and serum samples were taken simultaneously in the first diagnostic puncture at admission. RESULTS: All cases showed typical findings on the routine CSF and serum analysis: increased CSF total protein, increased Q (CSF/serum) albumin accompanied by eosinophilia in CSF. No intrathecal synthesis of immunoglobulins was found. Mean serum and CSF sICAM-1 values were 337.4 and 3.97 ng/mL. Qalbumin and QsICAM-1 mean values were 4.1 and 6.2 respectively. In 50% of the patients an increased brain-derived fraction of sICAM-1 was found. CONCLUSION: It may be suggested that a dynamic of the sICAM-1 brain derived fraction is perhaps associated to the immune response in the evolution of the disease.sICAM-1 may be an agent in negative feedback for eosinophils passage through the blood-CSF barrier into the inflammatory brain response.

Serum and cerebrospinal fluid concentrations of E-selectin in patients with aneurysmal subarachnoid hemorrhage

The goal of the present study was to determine concentrations of E-selectin in both cerebrospinal fluid (CSF) and serum of patients with aneurysmal subarachnoid hemorrhage (SAH) and to evaluate the correlation between the clinical parameters and E-selectin levels. Both CSF and serum samples obtained from 12 patients with aneurysmal SAH and 8 patients with hydrocephalus (control group) without any other known central nervous system disease were assayed for E-selectin by quantitative enzyme-linked immunosorbent assay and the results were compared between the two groups. Mean levels of soluble forms of E-selectin within the first 3 days and on the 5th and 7th days of SAH were 4.0 +/- 7.9, 2.8 +/- 5.2, and 3.1 +/- 4.9 ng/ml in the patient's CSF, and 33.7 +/- 9.2, 35.1 +/- 7.0, and 35.2 +/- 8.7 ng/ml in serum, respectively. In contrast, mean E-selectin levels were 0.1 +/- 0.2 ng/ml in CSF and 8.7 +/- 5.0 ng/ml in serum of control patients. The difference between groups was statistically significant regarding both CSF and serum E-selectin levels (P < 0.05). Thus, we have demonstrated a marked increase of E-selectin concentration in both CSF and serum of patients with aneurysmal SAH compared with control and suggest that blocking the interaction between E-selectin and vascular endothelium may have a beneficial effect on vasospasms.

CD14 deficiency leads to increased MIP-2 production, CXCR2 expression, neutrophil transmigration, and early death in pneumococcal infection

CD14 is a myeloid receptor for bacterial cell membrane/wall components, for which we previously showed a strong induction in cerebrospinal fluid (CSF) during meningitis. Here, we studied CD14 function in murine Streptococcus pneumoniae meningitis by using wild-type (WT), CD14(-/-) mice, and WT mice pretreated with neutralizing anti-CD14 antibodies. Early polymorphonuclear leukocytes (PMN) immigration was more pronounced in CSF of CD14(-/-) than of WT mice. This was not a result of altered adherence molecule expression in blood and CSF PMN or brain endothelial cells. Macrophage inflammatory protein-2 (MIP-2) and keratinocyte-derived chemokine levels were similar in CSF in both strains, but MIP-2 was higher in infected brain and in brain-derived endothelial cells infected in vitro in CD14(-/-) than in WT mice. CD14(-/-) PMN demonstrated increased expression of CXC chemokine receptor 2 (CXCR2) after infection and stronger in vitro chemotaxis than WT PMN toward CSF from WT or CD14(-/-) mice and toward MIP-2. Excess PMN migration in CD14(-/-) mice did not result in improved bacterial clearing but in increased tumor necrosis factor in CSF, higher disease severity, and earlier death. Pretreatment with anti-CXCR2 reduced PMN infiltration into CSF and brain MIP-2 production and abolished earlier mortality in CD14(-/-) mice. In conclusion, CD14 plays a protective role in pneumococcal meningitis by slowing PMN migration via MIP-2 and CXCR2 modulation.

Intrathecal sICAM-1 production in multiple sclerosis Correlation with triple dose Gd-DTPA MRI enhancement and IgG index

In this study the aim was to evaluate the intrathecal sICAM-1 production in multiple sclerosis (MS) patients during relapse and remission. In addition to this, we assessed whether there is a correlation between intrathecal sICAM-1 production and other disease activity markers such as IgG index and gadolinium enhancement in magnetic resonance imaging (MRI). Twenty four relapsing-remitting MS patients were included in the study. Serum and cerebrospinal fluid (CSF) samples were obtained both during relapse and remission. The soluble form of ICAM (sICAM) was measured by the ELISA method in serum and CSF. Cranial MRI with triple dose gadolinium injection was performed for each patient both during relapse and remission. Serum levels of sICAM-1 (245.23 +/- 92.88 ng/ml) were higher during relapse than those in remission (219.90 +/- 110.94 ng/ml), but the difference was not statistically significant. In relapse periods CSF levels of sICAM-1 (1.304 +/- 0.92 ng/ml) were higher than those in remission (1.06 +/- 0.86 ng/ml), but this was not significant. However, during relapse periods patients had significantly higher sICAM-1 index values (1.76 +/- 0.60) than those found during remission periods (1.01 +/- 0.44) (p < 0.05). The IgG index values were higher in relapse periods than in remission (0.88 +/- 0.37 vs. 0.67 +/- 0.28) (p < 0.005). On T1 weighted images following triple dose Gd injection, at least two or more enhancing lesions were present in 22/24 of the patients (91%) in relapse and 4/24 of the patients (19%) in remission. There was strong correlation both between the sICAM-1 index and Gd enhancement (r =0 .72 p < 0.05) and sICAM-1 index and IgG index in relapse (r = 0.69 p < 0.05). In conclusion, there is association between high sICAM-1 and IgG indices, as well as between high sICAM-1 index and Gd enhancing MRI lesions in relapsing MS patients.

The role of soluble intercellular adhesion molecules in neurodegenerative disorders

Immunological disturbances have been implicated in the pathogenesis of some neurodegenerative disorders like Alzheimer's disease (AD) and amyotrophic lateral sclerosis (ALS). Adhesion molecules are markers of activated endothelial cells upregulated by action of cytokines.

MATERIALS AND METHODS

To investigate the activation or not of the vascular cells in AD and ALS, serum soluble intercellular adhesion molecule-1 (ICAM-1) and soluble E-selectin were evaluated (enzyme-like immunosorbent assay, ELISA) in 22 patients with Alzheimer's disease (AD), 20 patients with amyotrophic lateral sclerosis (ALS), 34 patients with non-inflammatory neurological diseases (NIND) and 15 control subjects.

RESULTS

Patients with AD had higher s-ICAM-1 levels compared to NIND patients and control subjects (p<0.0027 and p<0.04, respectively). Patients with ALS had not higher s-ICAM-1 levels compared to NIND patients and control subjects (p<0.21 and p<0.31, respectively). Soluble-E-selectin levels in AD and ALS patients were not statistically different compared to NIND patients and controls (p<0.4, p<0.9 and p<0.3, p<0.19, respectively).

CONCLUSIONS

The presence of high s-ICAM values may be related to immunological processes involved in pathogenetic mechanisms of AD. The not statistically significant values of s-E selectin, a glycoprotein considered an exclusive marker of endothelial activation, seem to suggest the neural rather than the endothelial s-ICAM origin in patients with AD. The low values of s-ICAM-1 and sE-selectin in the serum of ALS patients do not exclude the presence of an unconventional immunological abnormality in this disorder.

Serum levels of soluble intercellular adhesion molecule-1 and soluble endothelial leukocyte adhesion molecule-1 in Alzheimer's disease

Serum soluble intercellular adhesion molecule-1 (s-ICAM-1) and soluble E-selectin (s-ELAM-1) were evaluated in 25 patients with Alzheimer's disease (AD), 54 patients with noninflammatory neurological diseases (NIND), and 15 control subjects. Patients with AD had a higher s-ICAM-1 level compared with the NIND patients and the control subjects (P< .001 and P< .04, respectively). The presence of high s-ICAM-1 values may be related to immunological processes involved in pathogenetic mechanisms of AD. The not statistically significant values of (s-ELAM-1), a glycoprotein considered an exclusive marker of endothelial activation, compared with the NIND patients and healthy subjects (P< .47 and P< .17, respectively), seem to suggest the neural rather than the endothelial s-ICAM origin in patients with AD.

Expression of ICAM-1 by osteoblasts in healthy individuals and in patients suffering from osteoarthritis and osteoporosis

OBJECTIVES

To describe the pattern of expression of intercellular adhesion molecule-1 (ICAM-1) at the surface of human osteoblasts (Ob) recovered from normal (control), osteoporotic (OP), and osteoarthritic (OA) bone. To relate ICAM-1 expression in OA Ob with interleukin-6 (IL-6) and prostaglandin E2 (PGE2) production.

MATERIALS AND METHODS

Trabecular bone specimens were taken from patients suffering from OA of the hip (n = 19) or knee (n = 19) or from hip fracture caused by osteoporosis (n = 10). Control bone specimens came from the posterosuperior iliac crest (n = 5) and from the femoral condyle of organ donors (n = 6). Bone explants were digested with collagenase and cultured. Ob were obtained after 6 weeks. ICAM-1 expression was studied by immunocytology. IL-6 and PGE2 were evaluated by standard ELISA.

RESULTS

Average ICAM-1 expression was different between control and OP bone (P < 0.02). Separation of specimens into high and low ICAM-1 expression showed a significant difference between high and low ICAM-1 expressors. The distribution of specimens after subclassification into high or low ICAM-1 expression groups revealed only 18.2% of patients in the high expression group for the controls, compared to 70% for OP bone (P < 0.03), 52.6% for hip OA and 47.4% for knee OA. IL-6 and PGE2 levels in OA Ob from both groups were found to be significantly elevated with high ICAM-1 expression compared to low ICAM-1 expression.

CONCLUSION

The results show that ICAM-1 expression in human bone seems to be pathology-dependent and correlates with IL-6 and PGE2 production, at least in OA individuals. This implies that ICAM-1 could discriminate functionally different populations of Ob and possibly alter the clinical evolution of the disease.

Increased diffusion of soluble adhesion molecules in meningitis, severe sepsis and systemic inflammatory response without neurological infection is associated with intrathecal shedding in cases of meningitis

OBJECTIVE

Sepsis and systemic inflammatory response syndrome (SIRS) result in the release in plasma of inflammatory cytokines and soluble forms of adhesion molecules in relation to endothelial activation. This study was designed to compare cerebrospinal fluid (CSF) concentrations of adhesion molecules in meningitis and SIRS without neurological infection and to evaluate in meningitis whether they originate from passive diffusion through damaged blood-CSF barrier or from local production.

DESIGN

Prospective observational study.

SETTING

University hospital medical intensive care unit.

PATIENTS

Nineteen patients with meningitis and 41 patients with sepsis or SIRS without cerebrospinal infection consecutively admitted to the critical care unit over an 18-month period.

INTERVENTIONS

Soluble forms of adhesion molecules (ICAM-1, VCAM-1, E-selectin) and cytokines (interleukin (IL)-1beta and TNF-alpha) were measured in paired CSF and blood samples.

RESULTS

Serum concentrations of soluble adhesion molecules and cytokines were increased in the two groups, without significant differences. The CSF concentrations were elevated in both cases, whereas patients with meningitis demonstrated significantly higher CSF concentrations of soluble ICAM-1, VCAM-1, E-selectin, and TNF-alpha ( p<0.001), with higher corresponding CSF/serum ratios. Correlations between CSF and serum concentrations were found only in meningitis. These correlations were strong for soluble ICAM-1 (r(2)=0.7, p<0.001) and E-selectin (r(2)=0.9, p<0.001), but weaker for VCAM-1. VCAM-1 CSF/serum ratios were increased, in comparison with ICAM-1 and E-selectin CSF/serum ratios, despite similar molecular weights. Serum and CSF levels of cytokines and adhesion molecules were not predictive of death for the whole population, except concentrations of ICAM-1 significantly increased in non-surviving patients ( p<0.05).

CONCLUSIONS

The CSF soluble adhesion molecules are increased in sepsis, SIRS and meningitis. In meningitis, the correlation between CSF and serum concentrations of adhesion molecules and the presence of a discrepancy of CSF/serum ratios for molecules of the same molecular weight may suggest intrathecal shedding in addition to diffusion through blood-CSF barrier.

Cytokine profile in cerebrospinal fluid of children with echovirus type 4 meningitis

Cytokines play a role in meningeal inflammation and leukocyte recruitment. Research has demonstrated that levels of different cytokines are elevated in aseptic and viral meningitis. Unfortunately, previous data were confounded by the inclusion of multiple viral agents as a study group. The aims of the study were to determine the cerebrospinal fluid concentrations of various cytokines in an outbreak of a single viral agent and to correlate between cytokine levels and leukocytes. Cerebrospinal fluid samples, collected during an outbreak of echovirus type 4 meningitis in infants and children in Israel, were tested for routine characteristics. In addition, cytokine levels were measured in 71 meningitis patients and compared with those of 11 nonmeningitis patients. Concentrations of interleukin-6 (2417 +/- 2713 vs 28 +/- 20 pg/mL; P < 0.01) and interferon gamma (36 +/- 38 vs 4.8 +/- 0.9 pg/mL; P < 0.01) were significantly higher in patients with meningitis than in the control group, whereas soluble intercellular adhesion molecule-1 (1.12 +/- 2.6 vs 0.06 +/- 0.1 ng/mL) levels did not differ significantly. In addition, only interleukin-6 levels correlated with leukocyte counts in viral meningitis patients. Interleukin-6 was the most sensitive and specific characteristic in predicting meningitis in this homogeneous group of patients. Furthermore, only interleukin-6 correlated with leukocyte counts in the cerebrospinal fluid.

Intercellular adhesion molecule-1 K469E polymorphism: study of association with multiple sclerosis

Intercellular adhesion molecule-1 (ICAM-1) is involved in the pathogenesis of multiple sclerosis (MS), whereas sequence variations in the ICAM-1 gene could potentially be responsible for the genetic susceptibility to MS. We studied an association of MS with the 13,848A>G (K469E) polymorphism of the ICAM-1 gene in Finnish and Spanish cases and controls and affected families. An increased risk for the AA (Lys(469)/Lys(469)) genotype was found in both populations. The effect observed was found to be strongest among the HLA-DQB1*0602-positive subjects, which implies genetic heterogeneity of MS. Meta-analysis of all published datasets supports increased risk of MS for the ICAM-1 Lys(469) homozygotes (relative risk = 1.3, p = 0.002).

Expression of matrix metalloproteinases, sICAM-1 and IL-8 in CSF from children with meningitis

The combined expression of the inflammatory mediators, matrix metalloproteinases (MMPs), soluble form of intracellular adhesion molecule ICAM-1 (sICAM-1) and interleukin (IL)-8, was evaluated in children infected with bacterial or viral meningitis. MMP-2 and IL-8 were detected in all CSF samples and were enhanced in both bacterial and viral infected samples, compared to those from control children. The expression of MMP-9 as well as sICAM-1 was not detected in control CSF while observed in viral infected and further elevated in bacterial infected samples. This pilot study supports a role for MMPs, IL-8 and sICAM in infectious meningitis and suggests further research to determine their possible use as biomarkers for various forms of meningeal infection as well as the use of their specific antagonists as potential therapeutic agents for central nervous system (CNS) inflammatory processes.

From farm to table to brain: foodborne pathogen infection and the potential role of the neuro-immune-endocrine system in neurotoxic sequelae

The American diet is among the safest in the world; however, diseases transmitted by foodborne pathogens (FBPs) still pose a public health hazard. FBPs are the second most frequent cause of all infectious illnesses in the United States. Numerous anecdotal and clinical reports have demonstrated that central nervous system inflammation, infection, and adverse neurological effects occur as complications of foodborne gastroenteritis. Only a few well-controlled clinical or experimental studies, however, have investigated the neuropathogenesis. The full nature and extent of neurological involvement in foodborne illness is therefore unclear. To our knowledge, this review and commentary is the first effort to comprehensively discuss the issue of FBP induced neurotoxicity. We suggest that much of this information supports the role of a theoretical model, the neuro-immune-endocrine system, in organizing and helping to explain the complex pathogenesis of FBP neurotoxicity.

Systemic inflammation in cardiovascular and periodontal disease: comparative study

Epidemiological studies have implicated periodontal disease (PD) as a risk factor for the development of cardiovascular disease (CVD). These studies addressed the premise that local infection may perturb the levels of systemic inflammatory mediators, thereby promoting mechanisms of atherosclerosis. Levels of inflammatory mediators in the sera of subjects with only PD, only CVD, both diseases, or neither condition were compared. Subjects were assessed for levels of C-reactive protein (CRP), serum amyloid A (SAA), ceruloplasmin, alpha(1)-acid-glycoprotein (AAG), alpha(1)-antichymotrypsin (ACT), and the soluble cellular adhesion molecules sICAM-1 and sVCAM by enzyme-linked immunoabsorbent and/or radial immunodiffusion assays. CRP levels in subjects with either condition alone were elevated twofold above subjects with neither disease, whereas a threefold increase was noted in subjects with both diseases (P = 0.0389). Statistically significant increases in SAA and ACT were noted in subjects with both conditions compared to those with one or neither condition (P = 0.0162 and 0.0408, respectively). Ceruloplasmin levels were increased in subjects with only CVD (P = 0.0001). Increases in sVCAM levels were noted in all subjects with CVD (P = 0.0054). No differences in sICAM levels were noted among subject groups. A trend toward higher levels of AAG was noted in subjects with both conditions and for ACT in subjects with only PD. Immunohistochemical examination of endarterectomy specimens of carotid arteries from subjects with atherosclerosis documented SAA and CRP deposition in association with atheromatous lesions. The data support the hypothesis that localized persistent infection may influence systemic levels of inflammatory mediators. Changes in inflammatory mediator levels potentially impact inflammation-associated atherosclerotic processes.

The role of inflammatory and immunological mediators in periodontitis and cardiovascular disease

Epidemiological studies have implicated periodontitis (PD) as a risk factor for development of cardiovascular disease (CVD). Persistent infections such as periodontitis induce inflammatory and immune responses which may contribute to coronary atherogenesis, and, in conjunction with other risk factors, may lead to coronary heart disease (CHD). In this review, mechanisms are described that may help explain the association between periodontal infections and CHD. Periodontal diseases are bacterial infections associated with bacteremia, inflammation, and a strong immune response, all of which may represent significant risk factors for the development of atherogenesis, CHD, and myocardial infarction (MI). Several mechanisms may participate in this association, including those induced by oral organisms, and those associated with host response factors. This review will focus on host factors. Oral pathogens and inflammatory mediators (such as interleukin [IL]-1 and tumor necrosis factor [TNF]-alpha) from periodontal lesions intermittently reach the bloodstream inducing systemic inflammatory reactants such as acute-phase proteins, and immune effectors including systemic antibodies to periodontal bacteria. This review will describe the potential role of various inflammatory as well as immunologic factors that may play a role in periodontitis as a possible risk factor for CHD.

Elevation of soluble intercellular adhesion molecule-1 levels in symptomatic and asymptomatic carotid atherosclerosis

OBJECTIVE

Recent data suggest that the increased expression of intercellular adhesion molecule-1 (ICAM-1) in atherosclerotic plaque taken from the carotid bifurcation correlates with the development of neurological symptoms. As a result, the authors sought to compare the serum levels of soluble forms of ICAM-1 (sICAM-1) in patients who were asymptomatic with those who were symptomatic for carotid artery stenosis as well as in patients who were matched in terms of sex, age, and risk factors who did not have carotid artery disease.

METHODS

Using enzyme-linked immunosorbent assay, serum sICAM-1 levels were prospectively determined in 54 patients scheduled to undergo carotid endarterectomy for either symptomatic or asymptomatic high-grade stenosis (> or =60%) and in 5 additional patient controls. Data are expressed as mean +/- standard error of the mean, with significance defined as P < 0.05 using the Mann-Whitney two-tailed test for two-column comparison or analysis of variance and Fisher protected least significant difference test.

RESULTS

Using a univariate model, serum sICAM-1 levels were significantly elevated in patients with carotid artery stenosis as compared with control patients without stenosis (347 +/- 15 ng/ml versus 216 +/- 8.2 ng/ml) (P < 0.01). When the asymptomatic and symptomatic patients with carotid artery stenosis were considered separately, these levels were still elevated relative to those of control patients (asymptomatic [312 +/- 18 ng/ml] and symptomatic [376 +/- 22 ng/ml] patients; P = 0.06 for asymptomatic versus control patients, P < 0.01 for symptomatic versus control patients). Symptomatic patients also had significantly elevated sICAM-1 levels as compared with asymptomatic patients (P < 0.05). Despite the fact that female patients demonstrated higher ICAM-1 levels than male patients (P < 0.05), sex, age, and risk factors such as the presence of hypercholesterolemia, diabetes, hypertension, or a history of smoking did not confound these findings.

CONCLUSION

Levels of sICAM-1 are higher in patients with carotid stenosis than in control patients. Symptomatic patients demonstrate significantly elevated levels as compared with asymptomatic patients. These data support the contention that ICAM-1 is a reliable marker of carotid disease progression and suggest that serum levels may be useful in following certain asymptomatic patients.

Blood-brain barrier function in cerebral malaria and CNS infections in Vietnam

BACKGROUND

The intraerythrocytic parasite Plasmodium falciparum induces the life-threatening neurologic syndrome of cerebral malaria (CM) from within cerebral blood vessels, without entering the brain parenchyma.

OBJECTIVES

1) To assess the use of CSF as an indicator of specific pathologic processes occurring in the brain during CM; 2) to compare this with other neurologic and infectious diseases to understand the distinct pathogenic features of CM; 3) to test the hypothesis that CM involves a specific functional breakdown of the blood-brain barrier (BBB).

METHODS

1) Radial immunodiffusion assays to detect albumin and IgG in matched plasma and CSF samples as indicators of BBB integrity and intrathecal IgG production; and 2) ELISA for soluble intracellular adhesion molecule-1 and sE-selectin, the cytokines tumor necrosis factor-alpha and transforming growth factor-beta1, and the matrix metalloproteinase MMP-9, to detect cellular activation and inflammatory responses within the brain.

RESULTS

Albumin and IgG indices implied only minimal degree of BBB breakdown in a few cases of CM, with most remaining within the normal range. In contrast, cryptococcal, tubercular, and acute bacterial meningitis produced detectable changes in the composition of the CSF and evidence of BBB breakdown.

CONCLUSIONS

CM appears to involve only subtle functional changes in BBB integrity with minimal intraparenchymal inflammatory responses compared with other neurologic infections. This focuses attention on local events within and around the cerebral microvasculature in CM, rather than indicating widespread parenchymal disease.

Cerebral Endothelial Cells Release TNF-α After Stimulation with Cell Walls of Streptococcus pneumoniae and Regulate Inducible Nitric Oxide Synthase and ICAM-1 Expression Via Autocrine Loops

TNF-α, inducible NO synthase (iNOS), and ICAM-1 are considered to be key proteins in the inflammatory response of most tissues. We tested the hypothesis that cell walls of Streptococcus pneumoniae (PCW), the most common cause of adult bacterial meningitis, induce TNF-α, iNOS, and ICAM-1 expression in rat primary brain microvascular endothelial cell cultures. We detected TNF-α mRNA by RT-PCR already 1 h after stimulation with PCW, while TNF-α protein peaked at 4 h (9.4 ± 3.6 vs 0.1 ± 0.1 pg/μg protein). PCW induced iNOS mRNA 2 h after stimulation, followed by an increase of the NO degradation product nitrite (18.1 ± 4 vs 5.8 ± 1.8 at 12 h; 18.1 ± 4 vs 5.8 ± 1.8 pmol/μg protein at 72 h). The addition of TNF-α Ab significantly reduced nitrite production to 62.2 ± 14.4% compared with PCW-stimulated brain microvascular endothelial cells (100%). PCW induced the expression of ICAM-1 (measured by FACS), which was completely blocked by TNF-α Ab (142 ± 18.6 vs 97.5 ± 12.4%; 100% unstimulated brain microvascular endothelial cells). Cerebral endothelial cells express TNF-α mRNA as well as iNOS mRNA and release the bioactive proteins in response to PCW. PCW-induced NO production is mediated in part by an autocrine pathway involving TNF-α, whereas ICAM-1 expression is completely mediated by this autocrine loop. By these mechanisms, cerebral endothelial cells may regulate critical steps in inflammatory blood-brain-barrier disruption of bacterial meningitis.

Soluble adhesion molecules in CSF are increased in children with severe head injury

Leukocyte-endothelial adhesion molecules, critical to the development of acute inflammation, are expressed in brain as part of the acute inflammatory response to traumatic brain injury (TBI). We measured the concentrations of the adhesion molecules P-selectin, ICAM-1, E-selectin, L-selectin, and VCAM-1 in ventricular cerebrospinal fluid (CSF) from children with severe TBI (Glasgow coma score < 8) and compared these findings with those from children with bacterial meningitis. P-selectin, an adhesion molecule associated with ischemia/reperfusion, was increased in children with TBI versus meningitis and control. Univariate and multivariate regression analyses demonstrated associations between CSF P-selectin and child abuse and age of < 4 years, and a significant, independent association between CSF intercellular adhesion molecule-1 (ICAM-1) and child abuse. These results are consistent with a specific acute inflammatory component to TBI in children. Future studies of secondary injury mechanisms and therapy after TBI should assess on the roles of P-selectin and ICAM-1 in injury and repair processes in brain after TBI.

Detection of soluble E-selectin, ICAM-1, VCAM-1, and L-selectin in the cerebrospinal fluid of patients after subarachnoid hemorrhage

OBJECT

The goal of this study was to explore whether the levels of soluble adhesion molecules were elevated in cerebrospinal fluid (CSF) after subarachnoid hemorrhage (SAH). This association was suggested by the known inflammatory response in vasospasm and the role of vascular adhesion molecules in regulating leukocytic adhesion to, and migration across, vascular endothelium.

METHODS

A prospective analysis was performed on CSF samples obtained in 17 patients who had suffered a recent aneurysmal SAH and in 16 control patients by using quantitative enzyme-linked immunosorbent assays for E-selectin, intercellular adhesion molecule-1 (ICAM-1), vascular adhesion molecule-1 (VCAM-1), and L-selectin. Levels of soluble forms of E-selectin (p=0.0013), ICAM-1 (p=0.0001), and VCAM-1 (p=0.048) were found to be elevated in the CSF of patients after SAH compared with levels in the CSF of norminal controls, patients with unruptured aneurysms, and patients tested months after SAH occurred. In addition, individual patients tested at the time of their initial ictus demonstrated a fall in adhesion molecule levels over time. Levels of E-selectin (p=0.044) were highest in patients who later developed moderate or severe vasospasm.

CONCLUSIONS

Adhesion molecules are known to be involved in white cell adherence to the endothelium and subsequent diapedesis and migration in which a role in initiation of tissue damage is postulated. The authors have demonstrated the elevation of three adhesion molecules, with severely elevated levels of E-selectin seen in patients who later develop vasospasm. A correlation with a role of vascular adhesion molecules in the pathogenesis of cerebral vasospasm is suggested.

Soluble and cell surface ICAM-1 as markers for disease activity in multiple sclerosis

OBJECTIVE

The intercellular adhesion molecule-1 (ICAM-1) is a member of the Ig supergene family. ICAM-1 is expressed on various cells like peripheral blood lymphocytes, endothelial cells or thymic cells and the cell surface form is supposed to be shed into a soluble form. The expression of ICAM-1 is induced by cytokines like Interleukin-1, TNF alpha or interferon gamma. The aim of the study was to investigate whether changes of cell surface and soluble ICAM-1 in the cerebrospinal fluid (CSF) and blood are indicative for disease activity in patients with multiple sclerosis (MS).

MATERIAL AND METHODS

In all patients with relapsing-remitting MS (relapse: n=31, remission: n=11) and controls (n=13) the expression of cell surface ICAM-1 (c-ICAM-1) was determined by two colour flow cytometry. Soluble ICAM-1 (s-ICAM-1) was measured by ELISA. Follow-up examinations were done 3 months later.

RESULTS

In 31 patients with a current relapse we found significantly decreased expression levels of c-ICAM-1 on leukocytes in CSF (P<0.001) and blood (P<0.10), when compared to those 11 individuals experiencing remission. In contrast we observed significantly (P<0.05) increased levels of s-ICAM-1 in CSF of patients with relapses. Comparing patients who had been in remission for more than 4 weeks (n=11) with remission lasting longer than 3 months (n=28) we detected stable c-ICAM-1 expression on CD3+ T cells in blood.

CONCLUSION

Our results demonstrate for the first time that c-ICAM-1 on CD3+ T-cells in CSF and blood is an activity marker in MS.

Soluble ICAM-1, demyelination, and inflammation in multiple sclerosis and acute optic neuritis

We measured sICAM-1 in paired samples of serum and cerebrospinal fluid (CSF) from patients with an attack of multiple sclerosis (MS) (n = 50) and patients with acute monosymptomatic optic neuritis (ON) as a possible first attack of MS were also included (n = 25). Based on calculations of extended indices we found evidence of intrathecal synthesis of sICAM-1 both in patients with clinically definite MS and in patients with idiopathic ON compared to neurological control subjects. The amount of intrathecally synthesized sICAM-1 correlated significantly to the CSF leukocyte count and to the concentration of myelin basic protein in the CSF. The serum concentrations of sICAM-1 were not increased in patients with demyelinating disease compared to the neurological control subjects.

Intercellular adhesion molecule-1 in cerebrospinal fluid--the evaluation of blood-derived and brain-derived fractions in neurological diseases

The soluble intercellular adhesion molecule-1 (sICAM-1) was measured in paired CSF and serum samples from 128 patients with different neurological diseases. The reference range of blood-derived sICAM-1 fractions in CSF was characterized with reference to the albumin CSF/serum quotients. The low mean concentrations of sICAM-1 of normal controls (n=33) in CSF (1.5 ng/ml; C.V.=40%) compared to serum (285.1 ng/ml; C.V.=32%) indicate that about 60% to 80% of sICAM-1 in normal lumbar CSF derives from blood. This calculation is based on the theoretically expected molecular size-dependent blood-CSF gradient between 300:1 to 250:1. In patients with non-inflammatory diseases (n=21) the sICAM-1 CSF/serum quotient increased non-linearly with increasing albumin CSF/serum quotient (blood-CSF barrier dysfunction) displaying the shape of a saturation-like curve in contrast to hyperbolic curves of other blood-derived proteins in CSF. This non-linear relation between sICAM-1 and albumin quotients does not allow a linear index evaluation reported in earlier studies. In bacterial meningitis (n=31) and viral meningoencephalitis (n=28) in addition to the increased blood-derived fraction, the brain-derived fraction of sICAM-1 in CSF was up to 12-fold higher than that in controls. The sICAM-1 CSF/serum quotients in MS (n=15) did not differ from non-inflammatory controls, i.e., there was no brain-dependent sICAM-1 fluctuation in CSF in contrast to the known fluctuations in blood. Earlier published reports on sICAM-1 have been controversial due to less sensitive assays and unsuitable linear evaluation concepts for blood-CSF barrier dysfunction.

Serum soluble intercellular adhesion molecule-I in MS: relation to clinical and Gd-MRI activity and to rIFN beta-Ib treatment

The validity of serum sICAM-I levels to assess Multiple Sclerosis (MS) activity was evaluated in 49 untreated definite relapsing-remitting (RR) patients. sICAM-I levels were significantly (P = 0.0009) higher in the 'clinically active' group (No 22) than in the 'clinically inactive' (No 27), whereas no different values were found between patients with Gd-enhancing lesions at MRI (Gd-positive) (No 32) and patients without such lesions (Gd-negative) (No 17) independently of their clinical activity. Among the 'clinically active' MS, the Gd-positive (No 16) subgroup showed significant (P < 0.05) lower sICAM-I levels when compared to the Gd-negative (No 6) subgroup, but higher (P = 0.009) than those of the 'clinically inactive Gd-positive' (No 16) patients. The sICAM-I levels did not differ between the two 'clinically inactive' subgroups Gd-positive (No 16) and Gd-negative (No 11). Finally the clinically active Gd-negative (No 6) showed sICAM-I levels higher (P = 0.002) than the clinically inactive Gd-negative (No 11). The specificity of high serum sICAM-I levels (above M +/- 2 s.d. of control values) to assess the disease activity in MS resulted higher (100%) using clinical than Gd-MRI activity (76%) as gold standard. The changes induced by 1 year recombinant Interferon-beta-Ib (rIFN beta-Ib) treatment on sICAM-I serum levels were also longitudinally investigated in 36 of the 49 RR MS. sICAM-I levels at baseline significantly increased in the first 2 months (baseline vs 1st month P < 0.0001 and 1st vs 2nd month P = 0.02), persisted at high levels without any significant change after 3 months, showed a temporary decrease at 6 months, then significantly increased again at 9 and 12 months. Fourteen patients experienced relapses, with a total of 20 relapses, during the whole treatment duration. The mean relapse/rate and the frequency of patients with Gd-positive MRI scans resulted significantly higher in the first semester compared to the second semester of treatment. This study adds further insights into the validity of serum sICAM-I to assess disease activity in MS and on the immunomodulatory properties of rIFN beta-Ib.

Soluble ICAM-1 in CSF coincides with the extent of cerebral damage in patients with severe traumatic brain injury

The intercellular adhesion molecule-1 (ICAM-1) expressed by endothelial cells is crucial in promoting adhesion and transmigration of circulating leukocytes across the blood-brain barrier (BBB). Migrated immunocompetent cells, in turn, release mediators that stimulate glial and endothelial cells to express ICAM-1 and release cytokines, possibly sustaining cerebral damage. Following activation, proteolytic cleavage of membrane-anchored ICAM-1 results in measurable levels of a soluble form, sICAM-1. The aims of this study were to investigate the changes of sICAM-1 levels in ventricular CSF and serum and to elucidate the influence of structural brain damage as estimated by computerized tomography (CT) as well as the extent of BBB dysfunction as calculated by the CSF/serum albumin ratio (QA) in patients with severe traumatic brain injury (TBI). All investigated parameters revealed two subgroups. Patients belonging to group A had sICAM-1 levels in CSF above normal range, presented marked cerebral damage and a disturbance of the BBB (range 0.6-24.7 ng/ml, n = 8). In contrast, patients belonging to group B had no elevation of sICAM-1 values in CSF (range 0.3-3.9 ng/ml, n = 5; p < 0.017) and showed minor cerebral damage with an intact BBB in most cases. In addition, overall analysis showed that sICAM-1 in CSF correlated with the extent of BBB damage as indicated by the QA (r = 0.76; p < 0.001). These results suggest that increased sICAM-1 levels in CSF might depict ongoing immunologic activation and that sICAM-1 correlates with the extent of tissue and BBB damage. The origin of soluble ICAM-1 in CSF and its pathophysiologic role after TBI remains to be clarified.

Three-dimensional and ultrastructural ICAM-1 distribution in the choroid plexus, arachnoid membrane and dural sinus of inflammatory rats induced by LPS injection in the lateral ventricles

To investigate immunological environment in the cerebrospinal fluid (CSF) system, ultrastructural and three-dimensional localization of intercellular adhesion molecule-1 (ICAM-1) was studied in the choroid plexus, arachnoid membrane and dural sinus of LPS-stimulated rats with immuno-SEM and TEM. The choroid plexus epithelial cells expressed rich ICAM-1 along the microvilli. The arachnoid trabeculae fibroblast-like cells demonstrated ICAM-1 expression on both sides facing the subarachnoid space moderately. The dural sinus endothelial cells, however, showed only few ICAM-1 expression and no specific localization. These results suggest that the choroid plexus and arachnoid membrane may play an important mutual role for leukocyte migration in the CSF system, and that the CSF system may function in immunoreaction independently of the vascular system with the aid of up-regulated ICAM-1 expression.

The relationship of soluble adhesion molecule concentrations in systemic and jugular venous serum to injury severity and outcome after traumatic brain injury

Adhesion molecules control the migration of leukocytes into tissue after injury. This may result in further cellular damage. We hypothesized that altered serum concentrations of soluble intercellular adhesion molecule (sICAM)-1 and soluble L-selectin (sL-selectin) after traumatic brain injury would correlate with injury severity and neurological outcome. We investigated serum concentrations of sICAM-1 and sL-selectin in 22 patients with traumatic brain injury admitted to the intensive care unit. The Glasgow Coma Scale (GCS) score and Injury Severity Score were recorded. Paired arterial and jugular venous blood samples were taken on admission and 24, 48, and 96 h after injury. Mean systemic and jugular venous concentrations of sICAM-1 were normal on admission but became significantly increased by 96 h (P = 0.018). sL-selectin concentrations of injured patients were markedly below those of controls at all time points (P < 0.001). There were no significant differences between jugular venous and arterial concentrations of either sICAM-1 or sL-selectin. Serum sICAM-1 was significantly related to neurological outcome (P < 0.001) and to the GCS score (P < 0.001). These changes in adhesion molecule expression after acute brain injury may be important in the pathophysiology of secondary injury. The highly significant relationship between serum sICAM-1 and neurological outcome suggests that the inflammatory response to injury may be detrimental. Drugs that antagonize the actions of the adhesion molecules may have a role in therapy after traumatic brain injury.

IMPLICATIONS

This observational study shows that there is a strong association between soluble intercellular adhesion molecule-1 in serum and poor neurological outcome after traumatic brain injury. This suggests that inflammation after brain injury may worsen the prognosis and that therapies directed against this inflammation may prove useful.

Soluble intercellular adhesion molecule-I (sICAM-I) in serum and cerebrospinal fluid of demyelinating diseases of the central and peripheral nervous system

Serum and cerebrospinal fluid (CSF) soluble intercellular adhesion molecule-I (ICAM-I) levels were evaluated (ELISA) in 22 untreated and 13 corticosteroid-treated active relapsing remitting (RR) Multiple Sclerosis (MS), in 10 untreated and 10 corticosteroid-treated Guillain-Barré syndrome (GBS) and in 17 non-inflammatory neurological diseases (NIND). Twenty-eight clinically inactive RR MS were assayed for serum sICAM-I before and after 3 months treatment of 8 MIU rIFN beta-Ib taken s.c. every other day. High sICAM-I serum levels above the NIND values were found in untreated clinically active MS and in untreated GBS (P < 0.05) but not in the untreated clinically inactive MS group. The active MS group showed significantly (P = 0.0001) higher sICAM-I serum levels if compared to the inactive group. Corticosteroid-treated active MS and GBS patients showed lower (P < 0.05) serum sICAM-I levels than the corresponding untreated groups. Serum sICAM-I levels after 3 months of rIFN beta-Ib treatment (P < 0.0001, paired t-test) resulted increased compared to pretreatment values in MS. The mean values of CSF/serum sICAM-I:CSF/serum Albumin ratios (sICAM-I Index) in active untreated MS patients were higher compared to NIND (P < 0.005) and to corticosteroid-treated MS group (P = 0.01). sICAM Index values in GBS did not differ from those in NIND. The results seem to suggest potential roles for serum sICAM-I in downregulating the ongoing inflammatory response at the blood-brain barrier level and for CSF sICAM-I in the maintenance of a central nervous system local immune response.

Reduced adhesion of PBMNCs to endothelium in methylprednisolone-treated MS patients: preliminary results

Methylprednisolone (MP) is a synthetic steroid commonly used in the treatment of multiple sclerosis (MS) relapses. It has a wide spectrum of activities on immune cells: it might also act by preventing mononuclear cell/endothelium adhesion. We studied adhesion phenomena between cultured human umbilical vein endothelial cells (HUVECs) and PBMNCs (CD45+, CD14+) from 6 MS patients treated in vivo with MP. We also studied fluctuations in CD11a and CD18 levels on lymphocytes and monocytes, as well as changes in serum sICAM-1 and sVCAM-1 concentrations. After MP treatment, PBMNCs adhesion to endothelium decreased at 3 h, while it went back to baseline levels at 24 h. A tendency to increase in both CD11a and CD18 on the surface of lymphocytes was detected, while an increase in serum sVCAM-1 was seen at 3 h.

Soluble adhesion molecules (sVCAM-1 and sICAM-1) in cerebrospinal fluid and serum correlate with MRI activity in multiple sclerosis

We performed a prospective study to correlate quantiative brain magnetic resonance imaging activity (gadolinium-diethylenetriaminepentaacetic acid enhancement) to cerebrospinal fluid and serum levels of soluble adhesion molecules in 46 patients with newly diagnosed multiple sclerosis (MS) and 30 control subjects with other diseases of the central nervous system. In all patients, magnetic resonance imaging of the brain and lumbar puncture were performed on the same day. In 32 (70%) of 46 MS patients, 8 (80%) of 10 patients with acute viral encephalitis, but none of the control subjects with noninflammatory diseases, gadolinium-enhancing lesions were detected. There was a significant correlation between the cerebrospinal fluid/serum ratios for soluble intercellular adhesion molecule-1 and soluble vascular cell adhesion molecule-1 as well as serum levels for both molecules and the area of gadolinium-enhancing lesions. No obvious correlation was observed between magnetic resonance imaging findings and cerebrospinal fluid cell count, protein concentration, or intrathecal immunoglobulin production. In patients with a single periventricular gadolinium-enhancing lesion (n = 16), we observed a strong negative correlation between the distance from the lateral ventricles and the cerebrospinal fluid/serum ratios for soluble intercellular adhesion molecule-1/albumin and soluble vascular cell adhesion molecule-1/albumin. These results suggest that intrathecal production of the two soluble adhesion molecules, as well as serum levels for soluble vascular cell adhesion molecule-1, in patients with MS reflect magnetic resonance imaging activity of typical periventricular lesions.

High levels of serum interleukin-10 are associated with a poor response to interferon treatment in patients with chronic hepatitis C

BACKGROUND

It still remains unclear whether some immunologic factors affect the response to interferon treatment. We therefore examined whether the pretreatment levels of serum interleukin-10 and soluble intercellular adhesion molecule-1 can be associated with the response to interferon treatment in patients with chronic hepatitis C.

METHODS

One hundred and two patients with chronic hepatitis C treated with interferon alpha-2b were divided into three groups on the basis of patterns of biochemical interferon response. Pretreatment levels of serum interleukin-10 and soluble intercellular adhesion molecule-1 were determined using enzyme-linked immunosorbent assay. Hepatitis C virus (HCV) typing was performed with a serologic enzyme-linked immunosorbent assay.

RESULTS

For patients with serotype I (n = 76) the numbers of sustained, transient, and non-responders were 12 (16%), 43 (56%), and 21 (28%), respectively. In serotype-I patients the pretreatment levels of serum interleukin-10 in non-responders were significantly higher than those in sustained or transient responders, although no significant differences were observed in HCV RNA quantity between them. There were no significant differences in the pretreatment levels of serum soluble intercellular adhesion molecule-1 among the three groups.

CONCLUSION

These findings suggest that high serum interleukin-10 levels may be related to a poor response to interferon treatment in serotype-I patients with chronic hepatitis C.

Immune-activation model in Alzheimer disease

About 10 years ago, we implicated immune factors in the pathophysiology of Alzheimer disease (AD), the hypothesis being that AD may be an immunologically derived systemic disease, but clinical effects confined primarily to the brain. We originally hypothesized that an immune basis of the disease may involve faulty immune regulation and autoimmunity. As described here, the activation of immunoregulatory T-lymphocytes with CD8 phenotype may be important in the immunopathogenesis of the disease.

A pilot study investigating the effects of orally administered pentoxifylline on selected immune variables in patients with multiple sclerosis

Multiple sclerosis is probably mainly mediated by T-helper 1 (TH1)-lymphocytes. TH1-function can be down-regulated in vitro and in animal experiments by pentoxifylline. Therefore, we included 20 multiple sclerosis patients in an open label pilot trial of pentoxifylline. Outcome parameter was the effect of treatment on levels of various cytokines and adhesion molecules in cerebrospinal fluid and serum, on production of TH1- and TH2-cytokines using cell stimulation assays, as well as on measures of T-cell activation and proliferation. Kurtzke's EDSS was a secondary efficacy parameter. A convincing and consistent effect of pentoxifylline could not be demonstrated.

Serum and cerebrospinal fluid levels of soluble adhesion molecules in multiple sclerosis: predominant intrathecal release of vascular cell adhesion molecule-1

Activated cerebral vascular endothelial cells express leukocyte, vascular cell, and intracellular adhesion molecules (E-selectin, VCAM-1 and ICAM-1) which facilitate leukocyte adhesion to endothelium and migration into inflammatory lesions. Paired serum and cerebrospinal fluid (CSF) levels of soluble (s) E-selectin, sVCAM-1 and sICAM-1 were determined by ELISA in patients with clinically definite MS in relapse, and patients with other inflammatory (IND) and non-inflammatory neurological disease (NIND). CSF levels of sVCAM-1 and sICAM-1 were significantly increased in MS patients compared to IND and NIND patients. Elevation of CSF sVCAM-1 in MS patients was the most marked finding (P = 0.0001) and an increased sVCAM-1 index indicated that this was due to intrathecal release of sVCAM-1. There were no differences in serum and CSF sE-selectin levels between the study groups. Measurement of the sVCAM-1 index may provide a marker of disease activity in patients with clinically definite MS.

Adhesion molecules in autoimmune disease

Leukocyte activation, circulation, and localization to inflammatory sites are dependent on adherence to molecules on other cells or to extracellular matrix ligands. Adhesion molecule expression and interactions are probably involved in initiation and propagation of autoimmune diseases. Adhesion molecules pertinent to the development of autoimmunity are the subject of this review. Material in this review was generated by a manual and a computerized search of medical literature pertaining to adhesion molecules and specific autoimmune diseases. Topics covered include adhesion molecule classification, regulation of adhesion, and characterization of adhesion receptors in specific autoimmune diseases, including rheumatoid arthritis (RA), systemic lupus erythematosus, Sjögren's syndrome, autoimmune thyroid disease, multiple sclerosis, and diabetes mellitus. Adhesion molecules are classified into selectin, integrin, and immunoglobulin supergene family groups. Increased adhesion molecule expression and avidity changes occurring with cellular activation are the principal methods regulating leukocyte adhesion. Tumor necrosis factor-alpha (TNF alpha), interferon-gamma (IFN-gamma), and interleukin-1 (IL-1) stimulate adhesion receptor expression on lymphoid and nonlymphoid tissues. Although differences between specific autoimmune diseases exist, key interactions facilitating the development of autoimmune inflammation appear to include L-selectin/P-selectin/E-selectin, lymphocyte function-associated antigen-1 (LFA-1)/intercellular adhesion molecule-1 (ICAM-1), very late antigen-4 (VLA-4)/vascular cell adhesion molecule-1 (VCAM-1), and alpha 4B7/MadCAM or VCAM-1 adhesion. Administration of anti-adhesion molecule antibodies in experimental animal models of autoimmunity and in a preliminary trial with RA patients has been successful in preventing or reducing autoimmune disease severity. A vast array of adhesive interactions occurs between immunocompetent cells, endothelium, extracellular matrix, and target tissues during the evolution of an autoimmune disease. Further characterization of leukocyte migration patterns and adherence should clarify pathogenic processes in specific autoimmune diseases and identify potential therapeutic targets for their treatment.

Low serum interleukin-10 levels in multiple sclerosis: further evidence for decreased systemic immunosuppression?

Serum interleukin 10 (IL10) levels were assessed in patients with multiple sclerosis who were either in a stable or active clinical condition. The levels were compared with values in healthy controls. Lower IL10 levels than in controls were seen in multiple sclerosis patients, regardless of clinical disease activity. Low IL10 levels were also seen in patients with systemic lupus erythematosus. No clear-cut relationships emerged between IL10 levels and those of tumour necrosis factor alpha and transforming growth factor beta, or between IL10 and lymphocyte subsets in peripheral blood.

Anti ICAM-1 (CD 54) monoclonal antibody reduces inflammatory changes in experimental bacterial meningitis

We investigated whether monoclonal antibodies directed against intracellular adhesion molecule 1 (ICAM-1 mAb) inhibit brain edema, increase of intracranial pressure (ICP), regional cerebral blood flow (rCBF) and recruitment of white blood cells (WBC) into the cerebrospinal fluid (CSF) in the rat model of the early phase of bacterial meningitis. Brain edema was assessed by brain water content determinations. rCBF measured by laser Doppler flowmetry and ICP were recorded continuously for 6 h after intracisternal challenge. Meningitis was induced with pneumococcal cell walls (PCW). Increase of ICP and brain water content were significantly inhibited (P <0.05) by intravenous treatment with ICAM-1 mAb (TM-8, 1 mg/kg). Furthermore, ICAM-1 mAb treatment profoundly attenuated (P <0.05) rCBF increase and WBC invasion into the CSF. These results suggest that the ICAM-1 pathway is critically involved in the early phase of bacterial meningitis.

Circulating intercellular adhesion molecule-1 (ICAM-1) as an early and sensitive marker for virus-induced T cell activation

The effect of systemic virus infection on the level of circulating ICAM-1 (cICAM-1) in serum, and the role of virus-activated T cells in this context, were studied using the murine lymphocytic choriomeningitis virus infection as primary model system. A marked virus-induced elevation in cICAM-1 in serum was revealed, the presence of which coincided with the phase of virus-induced T cell activation. However, high levels of cICAM-1 in serum were observed well before maximal T cell activation could be demonstrated. No increase in cICAM-1 was observed in the serum of infected T cell-deficient nude mice, clearly demonstrating that T cells were mandatory. Analysis of MHC class I and MHC class II-deficient mice revealed that either CD4+ or CD8+ T cells alone are sufficient, despite a markedly reduced inflammatory exudate in the former animals. These results indicate that virus-activated T cells induce shedding of ICAM-1 into the circulation, and this parameter may be used as an early and sensitive marker for immune activation.