Neuropathological spectrum in systemic lupus erythematosus: A single institute autopsy experience

AIM

Systemic lupus erythematosus (SLE) is a prototype autoimmune disease characterized by circulating autoantibodies and immune complexes involving virtually every organ of the body. However, with respect to central nervous system (CNS), the mechanism of injury is still debated as complement mediated or thrombo-ischemic in nature. We studied the spectrum of neuropathological changes in twelve autopsy cases of SLE and evaluated the role of immune-complexes and complement activation in contributing to the thrombo-ischemic injury and correlated these features with clinical profile.

METHODS

Autopsy records of all cases of SLE over a period of 20 years (2000-2019) were reviewed. Clinical history including neuropsychiatric symptoms and detailed histopathological analysis was performed. Direct immunofluorescence for IgM, IgG, IgA, C1q, C3, C4d, Kappa, Lambda and immunohistochemistry for C5b-9 was performed on lesional areas in paraffin embedded brain sections. Control tissue from brain was taken from two patients who died of sudden cardiac event.

RESULTS

Our cohort comprised of 12 cases with age range from 12 to 40 years and all were female patients. Microinfarction and vasculopathy seen in eight cases were the commonest findings. Four cases with microinfarcts had non-bacterial thrombotic endocarditis in heart. Microthrombi adjacent to microinfarcts were seen in 4 cases. Variable deposition of immunoglobulins (predominantly IgG) and complements (C1q, C3, C4d) was evident in cortical arterioles (2 cases) and small capillaries (1 case). Neurological symptoms were seen in four cases, of which, three had associated invasive fungal infection with secondary vasculitis. Active lupus vasculitis was identified in a single case. C5b-9 immunoexpression was not detected in any of the cases.

CONCLUSIONS

Our study adds observational data to the existing literature that the predominant neuropathological features of SLE are related to thrombo-ischemic injury and small vasculopathic changes. Only in a minor subset (25%), it is mediated by immune-complexes and complements. Immune-complex deposition on immunofluorescence in cortical vessels (cerebral lupus vasculopathy) is a novel finding which has not been reported earlier.

Neutrophil-to-Albumin Ratio as a Biomarker of Delayed Cerebral Ischemia After Aneurysmal Subarachnoid Hemorrhage

OBJECTIVE

This study set out to investigate the relationships between the neutrophil-to-albumin ratio (NAR) in the early stages of aneurysmal subarachnoid hemorrhage (aSAH) and the occurrence of delayed cerebral ischemia (DCI).

METHODS

A total of 439 patients with aSAH were included in this retrospective study. NAR assessment was conducted on admission. The relationship between NAR and DCI was analyzed.

RESULTS

Eighty-four patients (23.7%) experienced DCI. NAR levels were significantly higher in patients with DCI after aSAH than without DCI (median [interquartile range] 0.350 [0.274-0.406] vs. 0.240 [0.186-0.300]; P < 0.001). NAR levels were correlated with World Federation of Neurological Surgeons (WFNS) grade and modified Fisher (mFisher) grade (r = 0.505 and 0.394, respectively). NAR and mFisher grade were the independent predictors of DCI. Under receiver operating characteristic curve, NAR levels exhibited a significant discriminatory capability (area under the curve [95% confidence interval] 0.812 [0.740-0.823]; P < 0.001). The predictive power of NAR levels was similar to mFisher grade (P > 0.05).

CONCLUSIONS

NAR, in positive correlation with the severity of hemorrhage, appears to be a novel predictive biomarker of DCI after aSAH.

Cxcr4 distinguishes HSC-derived monocytes from microglia and reveals monocyte immune responses to experimental stroke

Monocyte-derived and tissue-resident macrophages are ontogenetically distinct components of the innate immune system. Assessment of their respective functions in pathology is complicated by changes to the macrophage phenotype during inflammation. Here we find that Cxcr4-CreER enables permanent genetic labeling of hematopoietic stem cells (HSCs) and distinguishes HSC-derived monocytes from microglia and other tissue-resident macrophages. By combining Cxcr4-CreER-mediated lineage tracing with Cxcr4 inhibition or conditional Cxcr4 ablation in photothrombotic stroke, we find that Cxcr4 promotes initial monocyte infiltration and subsequent territorial restriction of monocyte-derived macrophages to infarct tissue. After transient focal ischemia, Cxcr4 deficiency reduces monocyte infiltration and blunts the expression of pattern recognition and defense response genes in monocyte-derived macrophages. This is associated with an altered microglial response and deteriorated outcomes. Thus, Cxcr4 is essential for an innate-immune-system-mediated defense response after cerebral ischemia. We further propose Cxcr4-CreER as a universal tool to study functions of HSC-derived cells.

The effect of acupuncture on the expression of inflammatory factors TNF-α, IL-6,IL-1 and CRP in cerebral infarction: A protocol of systematic review and meta-analysis

BACKGROUND

The mechanisms of acupuncture on the treatment of cerebral infarction remain unclear, the aim of the present study was to provides a protocol of systematic review and meta-analysis, with which we will collect clinical evidence to verify whether acupuncture will have an effect on reducing the levels of tumor necrosis factor α (TNF-α), C-reactive protein (CRP), interleukin-1 (IL-1), and interleukin (IL-6) after cerebral infarction based on evidence-based studies.

METHODS

Included studies will be retrieved according to inclusion and exclusion criteria from 5 English databases (the MEDLINE via PubMed, the Cochrane Library, Embase, the Web of Science, and Ovid database), and 4 Chinese databases (China Science and Technology Journal Database (VIP), Chinese Biomedical Literature Database (CBM), Wan-fang Database, China National Knowledge Infrastructure (CNKI)) from October 1990 to October 2017. The inflammatory factor levels of TNF-α and IL-1,IL-6,CRP will be marked as major outcomes. We will use RevMan V.5.3 software to calculate the data synthesis and will conduct meta-analysis based on the collected data.

RESULTS

The inflammatory factor levels of TNF-α and IL-1,IL-6,CRP, mortality and adverse effects will be measured and comprehensively assessed to evaluate the adjunctive effect of XBP on CHF from this systematic review and meta-analysis with current clinical evidence.

CONCLUSION

The systematic review and meta-analysis will assess the effect of acupuncture on the expression of inflammatory factors TNF-α, IL-6, IL-1 and CRP in cerebral infarction with up-to-date clinical evidence.

PROSPERO REGISTRATION NUMBER

PROSPERO CRD42017078583.

Peripheral Th17/Treg imbalance in patients with atherosclerotic cerebral infarction

OBJECTIVE

CD4(+)CD25(+) regulatory T (Treg) cells and Th17 cells play important roles in peripheral immunity. Oxidized low-density lipoprotein (ox-LDL) is an instrumental factor in atherogenesis. However, the changes of Th17/Treg cells in patients with acute cerebral Infarction (ACI) and impact on Th17/Treg by ox-LDL are not clear. Here, we examined the balance of Th17/Treg in ACI patients and the effect of ox-LDL on this balance.

MATERIALS AND METHODS

The frequencies of Th17 and Treg cells, key transcription factors and relevant cytokines were examined in patients with ACI, Transient ischemic attack (TIA) and controls. The correlations of cytokines, inflammatory biomarkers and ox-LDL in serum to Th17/Treg frequency, and the effects of ox-LDL on Th17/Treg cells in vitro were analyzed.

RESULTS

ACI patients have shown a significant increase of Th17 frequency, RORγt expression and Th17 related cytokines (IL-17 and IL-6 ) levels, and a clear decline of Treg frequency, Foxp3 expression, suppressive function and regulatory cytokines (IL-10 and TGF-β1) levels. Furthermore, TIA patients also have notable variation as compared to control group. Serum ox-LDL and inflammatory biomarkers were positively correlated with the frequency of Th17 cells and negatively correlated with the frequency of Treg cells. Treg and Th17 cells from ACI patients were significantly susceptible to ox-LDL-mediated alterations in vitro.

CONCLUSIONS

Th17/Treg cells were imbalanced in ACI patients, and ox-LDL may contribute to this imbalance and lead to the occurrence of ACI suggesting their pathogenetic role in ACI.

[Inflammation as a therapeutic agent in cerebral infarction: cellular inflammatory response and inflammatory mediators]

INTRODUCTION

The immune central nervous system (CNS) innate immune cells including microglia and macrophages play integral roles in receiving and propagating inflammatory signals. Inflammation is generally a beneficial response of an organism to infection but, when prolonged or inappropriate, it can be detrimental. Neuronal loss in acute (e.g. stroke and head injury) and chronic (e.g. multiple sclerosis and Alzheimer's disease) CNS diseases has been associated with inflammatory processes systemically and in the brain.

DEVELOPMENT

Herein we review the processes that participate in the activation of the immune system and the starting of inflammatory response after stroke, where neuronal necrotic cell death has been described. We addressed the relevance of the innate inflammatory cells that are on the CNS, as microglia and macrophages, which have an important role in receiving and spreading inflammatory signals. In addition, the inflammatory response is characterized by an increase in the levels of expression of inflammatory mediators, which regulate adhesion molecules, and increase the permeability of the blood-brain barrier. It has also been described that inflammation promotes the rapid over-expression and activation of a variety of genes, and it has been postulated that transcription factors should be studied for their potential use in therapeutics and repair. Transcriptional activation can be a double-edged sword since depending on the individual transcription factor it can induce the expression of either neuroprotective or neurotoxic genes.

CONCLUSION

In summary, a better understanding of the different molecules mediating the immune response will allow the design of new pharmacological tools that could improve stroke treatment.

Study of anti-endothelial cell antibodies in SLE patients with acute ischemic stroke

Endothelial dysfunction is the predominant manifestation of SLE. Anti-endothelial cell antibodies (AECA) are a heterogeneous group of autoantibodies directed against different antigens in endothelial cells. The objective of this study was to assess the possible correlation between the presence of AECA and ischemic stroke manifestations in SLE. The AECA titers in serum from 34 patients with SLE and acute ischemic stroke (8 men and 26 women, mean age 38.37 +/- 3.25 years) and in 32 controls (11 men and 21 women, mean age 37.52 +/- 3.86 years) were tested. The method used was ELISA. The data were expressed as mean +/- SD from indicated number of patients. Comparison between patients and controls was expressed as relative risk with its 95% confidence interval (RR[95% CI]), where lower limit > 1.0 was considered significant. All p values were determined by Fisher's exact test. A value of p < 0.05 was considered statistically significant. AECA were positive in 31 out of 34 patients, mean value 19.2 +/- 16.3 U/mL and in 8 out of 32 controls, mean value 5.5 +/- 2.6 U/mL (RR 7.154 [95% CI 2.801 to 18.274]), p < 0.0001. Patients with SLE and acute ischemic stroke tended to have higher mean values of AECA. AECA play a pivotal role in the pathogenesis of neurologic complications of SLE. AECA titers in SLE patients with acute ischemic stroke support a role for AECA as potential diagnostic marker possibly associated to cerebral manifestations of SLE patients. Further study is needed in order to clarify if AECA presence is related to systemic diseases severity and to situate their importance among other markers of endothelial dysfunction.

Catastrophic multiple organ ischemia due to an anti-Pr cold agglutinin developing in a patient with mixed cryoglobulinemia after treatment with rituximab

Cold agglutinin disease occurring with cryoglobulinemia is a rare occurrence. Here, we report a patient with mixed cryoglobulinemia that was treated with rituximab and, after response, developed an anti-Pr cold agglutinin that manifested with hemolysis and microvascular occlusion causing mesenteric ischemia and cerebral infarction. Unlike previous reports of patients with cryoglobulinemia and cold agglutinin disease, our patient did not have a detectable cryoprecipitate when his cold agglutinin manifested.

Study of phosphatidylserine-dependent anti-prothrombin antibody in cerebral infarction

PURPOSE

This study was carried out to clarify the relationship of IgG phosphatidylserine-dependent anti-prothrombin antibody (aPS/PT), IgG beta 2 glycoprotein I-dependent anticardiolipin antibody (beta 2-GPI aCL), and lupus anticoagulant (LA) to cerebral infarction, using data from 93 patients who visited our hospitals.

MATERIALS AND METHODS

We computed the positive rates for each of IgG aPS/PT, beta 2-GPI aCL, and LA in the 93 patients with cerebral infarction, and carried out logistic regression analysis with IgG aPS/PT as the outcome variable and with beta 2-GPI aCL, LA, and each risk factor as predictor variables in order to assess the relationship of IgG aPS/PT with each factor.

RESULTS

IgG aPS/PT was more highly correlated with LA than beta 2-GPI aCL in IgG aPS/PT-positive patients with cerebral infarction. IgG aPS/PT itself appears to have high specificity as a marker for antiphospholipid syndrome (APS), because there were patients who were IgG aPS/PT-positive but both beta 2-GPI aCL- and LA-negative.

CONCLUSION

In IgG aPS/PT-positive patients with cerebral infarction, IgG aPS/PT is more highly correlated with LA than beta 2-GPI aCL. It is also strongly associated with APS. Measurement of IgG aPS/PT in patients with cerebral infarction could be of diagnostic value.

Measurement of platelet-derived microparticle levels in the chronic phase of cerebral infarction using an enzyme-linked immunosorbent assay

Assessment of platelet function is a critical component of the treatment and secondary prevention of cerebral infarction, and measurement of platelet-derived microparticle (PDMP) levels using flow cytometry may be a good indicator of platelet function. However, the flow cytometric analysis is not feasible in a variety of clinical situations. The goal of the present study was to measure PDMP levels using an enzyme-linked immunosorbent assay (ELISA) in chronic cerebral infarction patients and to determine the utility of PDMP level measurement for the monitoring of the effect of cilostazol and aspirin. A crossover study was performed using 4-weeks of aspirin (100 mg/day) and 4-weeks of cilostazol (200 mg/day) in 18 patients. PDMP levels were also measured in 20 volunteers as controls. Experiments demonstrated that PDMP levels were significantly higher in chronic cerebral infarction patients (median 8.8 U/ml, interquartile range 5.1-14.9 U/ml, n=18) than in controls (median 5.5 U/ml, interquartile range 5.0-8.2 U/ml, n=20) (P=0.047). PDMP levels did not decrease after therapy with either aspirin (median 10.9 U/ml, interquartile range 6.2-17.9 U/ml, n=12) or cilostazol (median 9.2 U/ml, interquartile range 6.1-14.3 U/ml, n=12) compared with baseline PDMP levels in the 12 patients who completed this trial (median 11.4 U/ml, interquartile range 5.2-23.7 U/ml, n=12). There were no significant differences in PDMP levels between aspirin and cilostazol (P=0.61). In conclusion, PDMP levels as measured by ELISA were increased in patients with chronic cerebral infarction regardless of the anti-platelet therapy. This methodology may be a useful strategy of assessing platelet function in chronic cerebral infarction patients.

Activation of Toll-like receptor 4 signaling contributes to hippocampal neuronal death following global cerebral ischemia/reperfusion

Toll-like receptors (TLRs) play a critical role in the induction of innate immune responses which have been implicated in neuronal death induced by global cerebral ischemia/reperfusion (GCI/R). The present study investigated the role and mechanisms-of-action of TLR4 signaling in ischemia-induced hippocampal neuronal death. Neuronal damage, activation of the TLR4 signaling pathway, expression of pro-inflammatory cytokines and activation of the PI3K/Akt signaling pathway in the hippocampal formation (HF) were assessed in wild type (WT) mice and TLR4 knockout (TLR4(-/-)) mice after GCI/R. GCI/R increased expression of TLR4 protein in the hippocampal formation (HF) and other brain structures in WT mice. Phosphorylation of the inhibitor of kappa B (p-IkappaB) as well as activation of nuclear factor kappa B (NFkappaB) increased in the HF of WT mice. In contrast, there were lower levels of p-IkappaB and NFkappaB binding activity in TLR4(-/-) mice subjected to GCI/R. Pro-inflammatory cytokine expression was also decreased, while phosphorylation of Akt and GSK3beta were increased in the HF of TLR4(-/-) mice after GCI/R. These changes correlated with decreased neuronal death/apoptosis in TLR4(-/-) mice following GCI/R. These data suggest that activation of TLR4 signaling contributes to ischemia-induced hippocampal neuronal death. In addition, these data suggest that modulation of TLR4 signaling may attenuate ischemic injury in hippocampal neurons.

Toll-like receptor 2 mediates CNS injury in focal cerebral ischemia

Toll-like receptors (TLR) recognize molecular structures associated with pathogens as well as host-derived components and initiate an inflammatory innate immune response. Microglia represent the resident immune host defense and are the major inflammatory cell type in the central nervous system (CNS). We show here that TLR2-deficient mice develop a decreased CNS injury compared to wild type mice in a model of focal cerebral ischemia. TLR2 mRNA is up-regulated in wild type mice during cerebral ischemia. In ischemic brains, TLR2 protein is expressed in lesion-associated microglia. Absence of TLR2 does not affect the recruitment of granulocytes to the infarct region. We conclude that TLR2 in microglia propagates stroke-induced CNS injury.

Intravenous immunoglobulin (IVIG) protects the brain against experimental stroke by preventing complement-mediated neuronal cell death

Stroke is among the three leading causes of death worldwide and the most frequent cause of permanent disability. Brain ischemia induces an inflammatory response involving activated complement fragments. Here we show that i.v. Ig (IVIG) treatment, which scavenges complement fragments, protects brain cells against the deleterious effects of experimental ischemia and reperfusion (I/R) and prevents I/R-induced mortality in mice. Animals administered IVIG either 30 min before ischemia or after 3 h of reperfusion exhibited a 50-60% reduction of brain infarct size and a 2- to 3-fold improvement of the functional outcome. Even a single low dose of IVIG given after stroke was effective. IVIG was protective in the nonreperfusion model of murine stroke as well and did not exert any peripheral effects. Human IgG as well as intrinsic murine C3 levels were significantly higher in the infarcted brain region compared with the noninjured side, and their physical association was demonstrated by immuno-coprecipitation. C5-deficient mice were significantly protected from I/R injury compared with their wild-type littermates. Exposure of cultured neurons to oxygen/glucose deprivation resulted in increased levels of C3 associated with activation of caspase 3, a marker of apoptosis; both signals were attenuated with IVIG treatment. Our data suggest a major role for complement-mediated cell death in ischemic brain injury and the prospect of using IVIG in relatively low doses as an interventional therapy for stroke.

Copolymer-1 (Cop-1) improves neurological recovery after middle cerebral artery occlusion in rats

The damage in ischemic stroke is caused by two events: (i) the ischemic phenomenon by itself; (ii) the self-destructive mechanisms developed as a consequence of ischemia. The inflammatory response is one of these destructive phenomena that accompanies and exacerbates the developing injury. Since it has been suggested that immune cells participate in neuroprotective and restorative processes, modulation rather than elimination of this inflammatory response could be a strategy to improve the neurological outcome. The immune modulator copolymer-1 (Cop-1), a synthetic basic random copolymer of amino acids, is a potent inducer of Th2 regulatory cells which, aside from exerting modulatory actions, is capable of releasing neurotrophic factors. There is evidence that Cop-1-specific T cells exert neuroprotective and even restorative effects in diverse neurodegenerative diseases. In order to test the ability of Cop-1 to prevent ischemic injury in a model of transient middle cerebral artery (MCA) occlusion, two groups of rats were treated either with Cop-1 or with saline solution (SS). Seven days after occlusion, Cop-1 treated rats presented a significant improvement in neurological function compared to SS-treated animals (1.2+/-0.4 and 2.8+/-0.5 mean+/-S.D., respectively; p=0.008). Histological findings showed that the percentage of infarct volume was smaller in Cop-1 treated rats (4.8+/-1.5), in comparison with those receiving SS (32.2+/-8.6; p=0.004). Cop-1 constitutes a promising therapy for stroke; thereby, the enforcement of further experimental investigation is encouraged in order to be able to formulate the best strategy.

Cannabinoid CB(2) receptor activation decreases cerebral infarction in a mouse focal ischemia/reperfusion model

Cannabinoid CB(2) Receptor (CB(2)) activation has been shown to have immunomodulatory properties without psychotropic effects. The hypothesis of this study is that selective CB(2) agonist treatment can attenuate cerebral ischemia/reperfusion injury. Selective CB(2) agonists (O-3853, O-1966) were administered intravenously 1 h before transient middle cerebral artery occlusion (MCAO) or 10 mins after reperfusion in male mice. Leukocyte/endothelial interactions were evaluated before MCAO, 1 h after MCAO, and 24 h after MCAO via a closed cranial window. Cerebral infarct volume and motor function were determined 24 h after MCAO. Administration of the selective CB(2) agonists significantly decreased cerebral infarction (30%) and improved motor function (P<0.05) after 1 h MCAO followed by 23 h reperfusion in mice. Transient ischemia in untreated animals was associated with a significant increase in leukocyte rolling and adhesion on both venules and arterioles (P<0.05), whereas the enhanced rolling and adhesion were attenuated by both selective CB(2) agonists administered either at 1 h before or after MCAO (P<0.05). CB(2) activation is associated with a reduction in white blood cell rolling and adhesion along cerebral vascular endothelial cells, a reduction in infarct size, and improved motor function after transient focal ischemia.

Psychoneuroimmunology of stroke

There is now considerable evidence from both experimental and clinical studies that immune and inflammatory processes can contribute to the onset of stroke and the neurologic and psychologic outcomes. Several specific therapeutic targets have been identified that may significantly improve the devastating impact of stroke.

Secretory phospholipase A2 IIA is up-regulated by TNF-alpha and IL-1alpha/beta after transient focal cerebral ischemia in rat

Cerebral ischemia initiates an inflammatory response in the brain that is associated with the induction of a variety of cytokines, including tumor necrosis factor-alpha (TNF-alpha) and interleukin-1alpha/beta (IL-1alpha/beta) that contributes to stroke injury. Transient middle cerebral artery occlusion (tMCAO) in spontaneously hypertensive rat (SHR) resulted in significant increases in TNF-alpha and IL-1beta levels. We have previously demonstrated up-regulation of secretory phospholipase A2 IIA (sPLA2 IIA) mRNA and protein expression, increased PLA2 activity, and loss of phosphatidylcholine after 1-h tMCAO and 24-h reperfusion in SHR. Treatment with TNF-alpha antibody or IL-1 receptor antagonist significantly attenuated infarction volume, sPLA2 IIA protein expression, PLA2 activity and significantly restored phosphatidylcholine levels after tMCAO. This suggests that cytokine induction up-regulates sPLA2 IIA protein expression, resulting in altered lipid metabolism that contributes to stroke injury.

Increased expression of cysteinyl leukotriene receptor-1 in the brain mediates neuronal damage and astrogliosis after focal cerebral ischemia in rats

Cysteinyl leukotrienes are potent pro-inflammatory mediators. Cysteinyl leukotriene receptor 1 is one of the two cysteinyl leukotriene receptors cloned. We recently reported that cysteinyl leukotriene receptor 1 antagonists protected against cerebral ischemic injury, and an inducible expression of cysteinyl leukotriene receptor 1 was found in neuron- and glial-appearing cells after traumatic injury in human brain. To determine the role of cysteinyl leukotriene receptor 1 in ischemic brain injury, we investigated the temporal and spatial profile of cysteinyl leukotriene receptor 1 expression in rat brain from 3 h to 14 days after 30 min of middle cerebral artery occlusion, and observed the effect of pranlukast, a cysteinyl leukotriene receptor 1 antagonist, on the ischemic injury. We found that cysteinyl leukotriene receptor 1 mRNA expression was up-regulated in the ischemic core both 3-12 h and 7-14 days, and in the boundary zone 7-14 days after reperfusion. In the ischemic core, cysteinyl leukotriene receptor 1 was primarily localized in neurons 24 h, and in macrophage/microglia 14 days after reperfusion; while in the boundary zone it was localized in proliferated astrocytes 14 days after reperfusion. Pranlukast attenuated neurological deficits, reduced infarct volume and ameliorated neuron loss in the ischemic core 24 h after reperfusion; it reduced infarct volume, ameliorated neuron loss and inhibited astrocyte proliferation in the boundary zone 14 days after reperfusion. Thus, we conclude that cysteinyl leukotriene receptor 1 mediates acute neuronal damage and subacute/chronic astrogliosis after focal cerebral ischemia.

[Study on plasma antibodies against heat shock protein 70 in the hypertensive patients with cerebral infarction]

OBJECTIVE

To determine the level of heat shock protein 70 (HSP70) antibody in the hypertensive patients with cerebral infarction and explore the role of plasma antibody against HSP70 in the pathogenesis of cerebral infarction and its relationship to the brain tissue damage.

METHODS

One hundred patients with CT or MRI confirmed cerebral infarction were enrolled in the study, in whom 64 were male, and 36 female. Among them, 67 patients were having hypertension and 33 with normal blood pressure. One hundred healthy individuals, including 58 male and 42 female, served as the control group. The level of plasma HSP70 antibody was determined with Western blot-enzyme linked immunoadsorbent assay (ELISA) technique.

RESULTS

Patients with cerebral infarction had a significantly higher incidence (69%) of antibodies to HSP70 compared to the low incidence (13%) of antibodies to HSP70 in the controls. Patients with hypertension had a high incidence (57%) of antibodies to HSP70 compared to the low incidence (12%) of antibodies to HSP70 in patients with normal blood pressure in cerebral infarction group. Patients with hypertension in the control group had a higher incidence (11%) of antibodies to HSP70 compared to the low incidence (2%) of antibodies to HSP70 in the same group.

CONCLUSION

There is a significant difference in the level of antibodies to HSP70 between patients with cerebral infarction and controls. Elevation in the level of antibodies to HSP70 may reflect the degree of brain tissue damage.

Schimke-immunoossäre Dysplasie

BACKGROUND

Schimke immuno-osseous dysplasia (SIOD) is a rare autosomal recessive multisystemic disorder caused by mutations of the SMARCAL 1 gene (SWI/SNF-related, matrix-associated, actin-dependent regulator of chromatin, subfamily a-like 1).

CLINICAL FEATURES

Main clinical features are: disproportional growth deficiency due to spondyloepiphyseal dysplasia, nephrotic syndrome with focal and segmental glomerulosclerosis, and defective cellular immunity. Patients with severe SIOD have life-limiting complications like cerebral ischemia due to vaso-occlusive processes. Only a few patients reached adulthood.

CASE REPORTS

The clinical course of four adult SIOD patients is presented.

CONCLUSION

Even patients with severe SIOD can reach adulthood. Therefore, doctors working in the field of internal medicine and family doctors should be familiar with the clinical picture of SIOD.

IgG and IgM isotypes of anti-cardiolipin and anti-beta2-glycoprotein i antibodies reflect different forms of recent thrombo-embolic events

We correlated the distribution and levels of serum anti-cardiolipin (aCL) and anti-beta(2)-glycoprotein-1 antibodies (anti-beta(2)-GPI) of the IgG and IgM isotypes to the clinical spectrum of recent (<6 months) thrombo-embolic events in a cohort of 162 patients. Clinical information was obtained by questionnaires from the referring physicians. Cerebro-vascular infarction (CVI) had taken place in 82 patients, deep venous thrombosis (DVT) in 34, pulmonary embolism (PE) in 14, myocardial infarction (MI) in four, and other thromboses in 28 patients. SLE was the most commonly associated rheumatic disease and accounted for 20 (12%) patients. In 124 (77%) patients no underlying rheumatic disease was identified. Isolated IgG aCL was found in 31 of 48 patients with DVT/PE (65%), but in only 21 of 82 patients with CVI (26%); p<0.0001. IgG anti-beta(2)-GPI were detected in 23 (48%) DVT/PE patients, but in only 13 (16%) CVI patients; p<0.001. The IgG class anti-beta(2)-GPI positive patients had significantly higher levels of IgG aCL (mean 65 units) compared to IgG anti-beta(2)-GPI negative patients (mean 29 units); p<0.0001. In contrast, isolated IgM aCL was found in nine (19%) patients with DVT/PE, but in 46 (56%) CVI patients; p<0.0001. Only ten patients had IgM anti-beta(2)-GPI. The present study shows that the IgG and IgM aCL isotypes seem to define different clinical subsets of patients with thrombo-embolic events with IgG aCL being most prevalent in the group having DVT/PE, IgM aCL being found primarily among CVI patients.

Aspects of gene polymorphisms in cerebral infarction: inflammatory cytokines

During the last decade, a growing corpus of evidence has indicated an important role of inflammatory cytokines in the pathogenesis of cerebral lesion following stroke. Recent data suggest that genetics may in turn contribute to modulating the effects of inflammatory cytokines on cerebral infarction (CI). This paper reviews the physiologic characteristics of major inflammatory cytokines and recent research developments related to cell biology and pathobiology in CI. In particular, this review focuses on the genetic aspects of inflammatory cytokines and their implications in CI.

IL-6: an early marker for outcome in acute ischemic stroke

OBJECTIVES

Inflammation plays an important role in the pathophysiology of stroke. We correlated interleukin (IL)-6, IL-10, C-reactive protein (CRP) and T-lymphocyte subtype levels in acute ischemic stroke patients with stroke volume and clinical outcome.

MATERIALS AND METHODS

Blood samples were obtained from 11 patients at defined intervals during 1 year. Nine healthy age-matched subjects served as controls. IL-6, IL-10 and CRP were quantified by enzyme-linked immunosorbent assay and T lymphocytes by flow cytometry. Volume measurement was carried out by computed tomography or magnetic resonance imaging and clinical outcome was scored by the European stroke scale (ESS) and Barthel index (BI).

RESULTS

IL-6 levels were increased in the acute phase of stroke compared with healthy controls (P = 0.002) and correlated with larger stroke volume (P = 0.012) and less favorable prognosis after 1 year, measured by ESS (P = 0.014) and BI (P = 0.006). IL-10, CRP and T-lymphocyte subtypes in the acute phase were not correlated with stroke volume or clinical outcome.

CONCLUSION

IL-6 seems to be a robust early marker for outcome in acute ischemic stroke.

[Effect of erigeron injection on platelet level of CD62p and serum content of TNF-alpha and IL-6 in patients with acute cerebral infarction]

OBJECTIVE

To investigate the clinical effect of Erigeron injection (El) on positive expression rate of CD62p in platelet and content of tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) in serum of patients with acute cerebral infarction (ACI).

METHODS

Sixty-eight patients with ACI were randomly divided into the treated group (n = 35) and the control group (n = 33). Conventional treatment were given to both groups, and EI 40 ml/d were given additionally to the treated group, the treatment course for both groups was 15 days. The positive expression of platelet CD62p and the serum TNF-alpha and IL-6 in patients before and after treatment were determined with flow cytometric (FCM) and electrochemical-luminescence (ECL) techniques respectively.

RESULTS

The total curative effect in the treated group were significantly higher than that in the control group (P < 0.05). Levels of platelet CD62p and serum TNF-alpha and IL-6 in ACI patients before and after treatment were significant higher than those in the healthy group (P < 0.05), all the three parameters were significantly decreased after treatment, and the lowering in the treated group was more significant than that in the control group (P < 0.05).

CONCLUSION

The effect of El on ACI patients may relate to its action in down-regulating the expression of platelet CD62p, alleviating the immune response and inflammatory injury of central nervous system induced by cytokines.

Adverse associations between CX3CR1 polymorphisms and risk of cardiovascular or cerebrovascular disease

OBJECTIVE

We investigated the role of monocyte-recruiting chemokines in cerebrovascular diseases among the subjects of the GENIC case-control study of brain infarction (BI).

METHODS AND RESULTS

Of the genotypes tested, only homozygosity for the rare CX3CR1 alleles was more frequent in cases than in controls: the I249 and M280 alleles were associated with an increased risk of BI (OR, 1.66 and OR, 2.62 with P<0.05, respectively). This effect was independent of other established risk factors and uncorrelated with disease severity. The study confirmed previous reports of a dominant protective association between CX3CR1-I249 allele and the risk of cardiovascular history. The risk of BI associated with homozygosity for the rare CX3CR1 alleles was enhanced in patients with no previous cardiovascular events. Ex vivo studies showed that the number of monocytes adhering to immobilized CX3CL1, the CX3CR1 ligand, increased proportionally to the number of CX3CR1 mutated alleles carried by the individual.

CONCLUSIONS

The rare CX3CR1 alleles were associated with an increased risk of BI and with reduced frequency of cardiovascular history. We propose that the extra adhesion of monocytes observed in individuals carrying rare alleles of CX3CR1 may favor mechanisms leading to stroke.

Strong correlation between the prevalence of cerebral infarction and the presence of anti-cardiolipin/beta2-glycoprotein I and anti-phosphatidylserine/prothrombin antibodies--Co-existence of these antibodies enhances ADP-induced platelet activation in vitro

Cerebral infarction is the most common arterial thromboembolic complication in the anti-phospholipid antibodies (aPL) syndrome. In an effort to clarify the roles of aPL in the pathogenesis of cerebral infarction in patients with SLE, we examined the levels of anti-cardiolipin/2-glycoprotein I antibodies (anti-CL/beta2-GPI) and anti-phosphatidylserine/prothrombin anti-bodies (anti-PS/PT) in addition to lupus anticoagulant (LA) activity in 126 patients with SLE (35 with cerebral infarction and 91 without thrombosis). Both anti-CL/beta2-GPI and anti-PS/PT strongly correlated with the presence of LA activity. The prevalence of cerebral infarction was obviously higher in the patients who had both anti-CL/beta2-GPI and anti-PS/PT (76.5% [26/34 cases], p<0.0001) than in the other patients having anti-CL/beta2-GPI or anti-PS/PT alone or neither of them (9.8% [9/92 cases]). Furthermore, we studied the in vitro effects of anti-CL/beta2-GPI and/or anti-PS/PT on the enhancement of platelet activation induced by stimulation with a low concentration of adenosine diphosphate (ADP). The purified IgG containing both anti-CL/beta2-GPI and anti-PS/PT caused significant enhancement of platelet activation caused by ADP. However, the purified IgG containing either anti-CL/beta2-GPI or anti-PS/PT had no enhancing effects on it. Furthermore, platelet activation was generated by the mixture of anti-CL/beta2-GPI-IgG and anti-PS/PT-IgG prepared from individual patients, but not by each fraction alone. These results indicate that anti-CL/beta2-GPI and anti-PS/PT may cooperate to promote platelet activation, which may contribute to the risk of cerebral infarction in patients with SLE.

A role for interferon-gamma in focal cerebral ischemia in mice

The pro-inflammatory cytokine interferon-gamma (IFNgamma) has traditionally been associated with inflammatory CNS disease and more recently with ischemia-induced pathology. Using a murine model of focal cerebral ischemia, we found no evidence for induction of IFNgamma mRNA after permanent middle cerebral artery occlusion. In addition, we found that mice deficient in IFNgamma or IFNgamma receptors developed neocortical infarcts similar in size to those in wild type. In contrast, MBP promoter-IFNgamma-transgenic mice consistently developed significantly larger infarcts than non-transgenic mice. Because IFNgamma is a potent activator of microglia-macrophages, we investigated the involvement of microglial-macrophage-derived TNF in the larger infarcts. Numbers of TNF mRNA-expressing microglia-macrophages and levels of TNF mRNA and TNF in IFNgamma-transgenic and non-transgenic mice were similar. Furthermore, the ischemic brain damage in IFN-gamma-transgenic mice was unaffected by recombinant soluble TNF receptor I. Taken together, the data argues against a role for IFNgamma in cerebral ischemia under normal conditions. However, when present, IFNgamma significantly exacerbates ischemia-induced brain damage by mechanisms that appear to be independent of TNF or synergistic neurotoxic interactions of IFNgamma and TNF Irrespective of the mechanism(s) involved, this enhancing effect of IFNgamma on ischemia-induced neurotoxicity may need to be considered in diseases where immune IFNgamma is involved, such as multiple sclerosis.

A novel mechanism of FK506-mediated neuroprotection: Downregulation of cytokine expression in glial cells

Immunosuppressant FK506 is neuroprotective in experimental models of cerebral ischemia, but the molecular mechanisms underlying this neuroprotection remain unknown. We have demonstrated that FK506 inhibits the signaling pathways that regulate hypertrophic/proliferative responses in cultured astrocytes. Ischemia/reperfusion injury is associated with the proliferation and hypertrophy of astrocytes and with inflammatory responses. In the present work, we sought to determine whether FK506 neuroprotection after middle cerebral artery occlusion (MCAo) in rat is mediated via suppression of glia activation and changes in cytokine expression. Neurological deficits, infarct size, and astrocyte/microglial response were quantified in rats subjected to 90 min of MCAo. Changes in the mRNA expression of interleukin-1beta (IL-1beta), IL-6, and tumor necrosis factor-alpha (TNF-alpha) in ipsilateral and contralateral cortices were determined by reverse transcription-polymerase chain reaction (RT-PCR). FK506 administered at 1 mg/kg, 60 min after MCAo, produced a significant improvement in neurological function and reduction of infarct volume. In FK506-treated rats, a significant reduction of IL-1beta, IL-6, and TNF-alpha expression was observed 12 h after reperfusion. FK506 neuroprotection was associated with a significant downregulation of IL-1beta expression in astrocytes and microglia in the injured side. FK506 selectively decreased the levels of TNF-alpha, and IL-1beta mRNAs in astrocytes in vitro, with no effect on transforming growth factor-beta 1 (TGF-beta1) and IL-6 expression. Moreover, FK506 inhibits lipopolysaccharide (LPS)-induced activation and cytokine expression in microglia in vitro. Our findings suggest that astrocytes and microglia are targets for FK506, and that modulation of glial response and inflammation may be a mechanism of FK506-mediated neuroprotection in ischemia.

The effect of Jeo Dang-Tang on cytokines production in the patients with cerebral infarction

The herbal formulation "Jeo Dang-Tang" (JDT) has long been used for various cerebrovascular diseases. However, very little has scientific investigation been carried out. The aim of the present study is to investigate the effect of JDT on the production of various cytokines in the patients with cerebral infarction (CI). Peripheral blood mononuclear cells (PBMC) obtained from the patients with CI were cultured for 24h in the presence or absence of lipopolysaccharide (LPS) or phytohemagglutinin (PHA). The amount of interleukin (IL)-4, IL-10 and transforming growth factor (TGF)-1beta, in culture supernatant, was significantly increased in the JDT, LPS or PHA treated cells compared to unstimulated cells (P < 0.05). We also show that increased IL-4, and IL-10 level by LPS or PHA was significantly inhibited by JDT in a dose-dependent manner. Maximal inhibition rate of IL-4 and IL-10 production by JDT was 45 +/- 2% and 51 +/- 5% for LPS-stimulated cell and 41.5 +/- 3% and 70.8 +/- 2% for PHA-stimulated cells, respectively (P < 0.05). On the other hand, JDT significantly increased the LPS or PHA-induced TGF-beta1 production (P < 0.05). These data suggest that JDT has a regulatory effect on the cytokines production, which might explain its beneficial effect in the treatment of CI.

Honokiol protects rat brain from focal cerebral ischemia–reperfusion injury by inhibiting neutrophil infiltration and reactive oxygen species production

We have previously shown that honokiol, an active component of Magnolia officinalis, displayed protective effect against focal cerebral ischemia-reperfusion (FCI/R) injury in rats. Production of reactive oxygen species (ROS) and infiltration of neutrophils to injured tissue play deleterious roles during cerebral ischemia. To study the mechanism(s) in mediating neuroprotective effect of honokiol, FCI/R-induced neutrophil infiltration and lipid peroxidation in brain tissue, and activation of neutrophils in-vitro were examined. Intravenous administration of honokiol (0.01-1.0 microg/kg) 15 min before (pretreatment) or 60 min after (post-treatment) middle cerebral artery occlusion reduced the total infarcted volume by 20-70% in dose-dependent manner. Pretreatment or post-treatment of honokiol at concentration of 0.1 and 1.0 microg/kg significantly decreased the neutrophil infiltration in the infarcted brain. Time course of neutrophil infiltration was performed in parallel with the lipid peroxidation in infracted brain tissue during FCI/R injury. The results indicate that honokiol can protect brain tissue against lipid peroxidation and neutrophil infiltration during FCI/R injury and cerebral infarction induced by FCI/R is accompanied with a prominent neutrophil infiltration to the infarcted area during FCI/R course. In-vitro, honokiol (0.1-10 microM) significantly diminished fMLP (N-formyl-methionyl-leucyl-phenylalanine)- or PMA (phorbol-12-myristate-13-acetate)-induced neutrophil firm adhesion, a prerequisite step behind neutrophil infiltration, and ROS production in neutrophils. Intracellular calcium overloading activates calcium-stimulated enzymes and further exaggerates FCI/R injury. Honokiol (0.1-10 microM) impeded the calcium influx induced by fMLP (a receptor agonist), AlF(4)(-) (a G-protein activator) or thapsigargin (an intracellular calcium pool releaser). Therefore, we conclude that the amelioration of FCI/R injury by honokiol can be attributed to its anti-oxidative and anti-inflammatory actions through, at least in part, limiting lipid peroxidation and reducing neutrophil activation/infiltration by interfering firm adhesion, ROS production, and calcium overloading that may be primed/activated during FCI/R injury.

Study on relationship between anticardiolipin antibody and cerebrovascular diseases

Serum anticardiolipin antibody (ACA) was measured in 91 patients with cerebral infarction (CI), 42 patients with cerebral hemorrhage (CH) and 30 healthy controls. The results showed that the ACA in CI and CH patients was significantly higher than in controls and IgG-ACA was the most important isotype. Stroke in ACA positive group tended to be recurrent and of multi-focuses. Positive rate of IgG-ACA reached its peak within the first week after stroke onset. The results suggested that ACA was an independent risk factor in CI and CH and might be valuable in stroke prediction.

Association of interleukin-1 alpha gene polymorphism with cerebral infarction

Interleukin-1 (IL-1) has pleiotropic actions in the central nervous system. During the last decade, a growing corpus of evidence has indicated an important role of this cytokine in the development of brain damage following cerebral ischemia. The expression of IL-1 in the brain is dramatically increased during the early and chronic stage of infarction. The IL-1 gene cluster on chromosome 2q14 contains three related genes (IL1alpha, IL1beta, and IL1 receptor antagonist) located within a 430-kb region. T and C alleles exist for the IL-1alpha-889 regulatory region and the TT genotype has been reported to increase the production of the protein in lipopolysaccharide (LPS)-stimulated mononuclear cells from IL-1alpha-889 TT carriers. We examined whether the IL-1alpha polymorphism affects the probability of cerebral infarction (CI). We genotyped 360 CI patients and 519 healthy controls for the same polymorphism. A significant increase was found for the IL-1alpha T allele in CI patients compared with controls (chi2=5.026, P=0.025). We conclude that the IL-1alpha-889 polymorphism is a major risk factor for CI in Koreans.

Regulation of TH1/TH2 cytokine production by Chungsim-Yeunja-Tang in patients with cerebral infarction

Chungsim-Yeunja-Tang is a prescription for the Taeumin cerebral infarction (CI) patients according to Sasang constitutional philosophy. Taeumin patients with CI were treated with CY-Tang during the acute stage. Clinical signs of CI disappeared markedly in about 2 weeks after oral administration of CY-Tang in all patients. The mean interleukin (IL)-2 plasma levels were slightly lower in the patients with CI than in the normal groups, whereas the mean TNF-alpha, IL-4, IL-6, and IgE levels were significantly higher in the patients with CI. There were no significant differences in interferon-gamma (IFN-gamma) levels between the groups. Serum IFN-gamma and IL-2 levels derived from (Th) 1 cells were significantly elevated in the patients with CI by CY-Tang administration. Significant reduced plasma levels of IL-4 and IL-6 derived from Th2 cells and IgE were observed in the patients treated with CY-Tang. Plasma levels TNF-alpha derived from Th1 significantly increased in the patients treated with CY-Tang. During the period of CY-Tang administration, there were no other adverse effects. The data indicate that CY-Tang has a good CI treatment effect, and that its action may be due to the regulation of cytokine production.

Changes in oxidative stress, iNOS activity and neutrophil infiltration in severe transient focal cerebral ischemia in rats

Oxidative stress, inducible nitric oxide synthase (iNOS) and neutrophils all contribute to post-ischemic brain damage. This study has determined the time courses of these three phenomena after ischemia in parallel with histological and functional outcomes. Ischemia was produced in rats by occluding the left middle cerebral artery and both common carotid arteries for 20 min. Regional cerebral blood flow (rCBF) rapidly decreased to 20% of its preischemic value during occlusion and stabilized at 60% following reperfusion. The striatal infarction was maximal 15 h after reperfusion (50+/-3 mm(3)), whereas the cortical infarction reached its maximum at 48 h (183+/-10 mm(3)). This drastic decrease in rCBF followed by incomplete reperfusion and massive infarction is, thus, extremely severe. The cortical infarction was strongly correlated with the neurologic deficit and loss of body weight. Oxidative stress, evaluated by the decrease in glutathione concentrations, appeared in the striatum at 6 h after reperfusion and in the cortex at 15 h. Calcium-independent NOS activity, considered as inducible NOS activity, was significantly enhanced at 24 h in the striatum and at 48 h in the cortex. Myeloperoxidase activity, a marker of neutrophil infiltration, was significantly increased at 48 h in both the striatum and cortex. These time courses show that the delayed iNOS activity and neutrophil infiltration that occur after the maturation of infarction in severe ischemia may not contribute to ischemic brain damage. By contrast, early oxidative stress may well be implicated in cerebral injury.

Adult stroke and perinatal brain damage: like grandparent, like grandchild?

Biomarkers of inflammation are found in the circulation of adults who have had a stroke. Although these biomarkers may, in part, be indicators of damage, some appear to contribute to damage. Similar biomarkers are found in newborns with cerebral white matter damage or at risk of cerebral palsy. Can we learn about the pathogenesis of neonatal white matter damage from what has been learned about the inflammatory correlates of adult stroke? We discuss relevant findings about systemic inflammatory markers in adult stroke and relate this information to our current understanding of cerebral white matter damage in newborns, especially those born at an extremely low gestational age. We also describe desirable characteristics of future studies of perinatal brain damage that involve measurements of systemic biomarkers.

The administration of complement component C9 augments post-ischemic cerebral infarction volume in neonatal rats

To determine whether ischemic cerebral infarction is mediated in part by complement component C9, C9-deficient neonatal rats were subjected to unilateral cerebral ischemia. Brains were harvested 24 h later, stained with 2,3,5-triphenyl tetrazolium chloride, and cerebral infarct volumes were quantified by computer-based planimetry. Compared with buffer, prophylactic intraperitoneal (i.p.) administration of the complement inhibitors soluble complement receptor type 1 (sCR1), a molecular hybrid of sCR1 and the selectin inhibitor sialyl Lewis x (sCR1-sLex), or cobra venom factor did not affect the cerebral infarct volume. In contrast, i.p. human C9 (75 microg/g body weight) significantly increased the volume of infarct located 6 through 10 mm posterior to the frontal pole. Therefore, in the post-ischemic brain, C9 was neurotoxic and augmented the focal cerebral infarct volume.

Inflammatory response and glutathione peroxidase in a model of stroke

Stroke is one of the leading causes of death in major industrial countries. Many factors contribute to the cellular damage resulting from ischemia/reperfusion (I/R). Experimental data indicate an important role for oxidative stress and the inflammatory cascade during I/R. We are testing the hypothesis that the mechanism of protection against I/R damage observed in transgenic mice overexpressing human antioxidant enzymes (particularly intracellular glutathione peroxidase) involves the modulation of inflammatory response as well as reduced sensitivity of neurons to cytotoxic cytokines. Transgenic animals show significant reduction of expression of chemokines, IL-6, and cell death-inducing ligands as well as corresponding receptors in a focal cerebral I/R model. Reduction of DNA binding activity of consensus and potential AP-1 binding sites in mouse Fas ligand promoter sequence was observed in nuclear extracts from transgenic mice overexpressing intracellular glutathione peroxidase compared with normal animals following I/R. This effect was accompanied by modulation of the c-Jun N-terminal kinase/stress-activated protein kinase pathway. Cultured primary neurons from the transgenic mice demonstrated protection against hypoxia/reoxygenation injury as well as cytotoxicity after TNF-alpha and Fas ligand treatment. These results indicate that glutathione peroxidase-sensitive reactive oxygen species play an important role in regulation of cell death during cerebral I/R by modulating intrinsic neuronal sensitivity as well as brain inflammatory reactions.

[A study on relation between active pulmonary tuberculosis and underlying diseases]

A study was made on the relation between active pulmonary tuberculosis and underlying diseases in 119 tuberculosis patients. Out of total 119 patients, 87 patients (73.1%) had underlying diseases. The most common underlying disease was diabetes mellitus in 34 patients (39.1%), followed by HCV (+) chronic hepatitis, sequela of cerebral infarction, hypertension and gastric ulcer. In patients who had underlying diseases, the mean age was higher, proportion of sputum smear positive cases was higher, albumin was lower, and period until sputum culture negative conversion was longer. In patients who had diabetes mellitus, proportion of cases with cavity on chest X-P was higher, and in patients who had sequela of cerebral infarction or hypertension, mean age was higher. In patients who had diabetes mellitus and whose HbA1C was > or = 9%, proportion of smear positive cases was higher, albumin was lower and period until culture negative conversion was longer than in patients who had diabetes mellitus and whose HbA1c was < 9%, suggesting that control of blood sugar in diabetes mellitus related to severity of pulmonary tuberculosis. In patients who had diabetes mellitus and whose albumin was < 3 g/dl, period until culture negative conversion was longer than in patients who had diabetes mellitus and whose albumin was > or = 3 g/dl. In patients who had underlying diseases, these diseases caused decline of tuberculous immunity and nutritional disturbance represented by lower albumin also promoted decline of tuberculous immunity. It is suggested that the underlying diseases affected the onset and progression of pulmonary tuberculosis.

Association of immune responses and ischemic brain infarction in rat

Inflammation plays an important role in the pathogenesis of neurodegenerative diseases including ischemia. Occlusion of common carotid artery and middle cerebral artery has been used to produce focal ischemic lesions in the rat. Here, we examined the associations between immune reactions and postischemic brain infarction. Ischemia/reperfusion time-dependently caused brain infarction. The kinetics of inflammatory reactions in rat brain including inflammatory cell infiltration, edema formation, cytokines/chemokines and adhesion molecules production and matrix metalloproteinase activation were relevant to the progression of ischemic infarction. Differential induction profile after ischemia suggests that this activation might contribute to secondary brain damage in ischemic tissues. On the other hand, another possibility of this response is to trigger processes that mediate the neural regeneration after ischemic injury.

[Study of lymphocyte and NK cell activity during mild hypothermia therapy]

Infectious disease is a common complication of mild hypothermia therapy. However, very little has been reported about immune response during hypothermia. In the present study, the number and subset of peripheral lymphocytes and mitogen response to phytohaemagglutinin (PHA) and concanavalin A (Con-A) were examined in 14 patients who received mild hypothermia therapy. NK cell ratio and activity were also examined in the same patients. Six out of 14 patients had complicated infectious diseases during mild hypothermia therapy. Five of them had pneumonia and the remaining one had thrombophlebitis. The number of peripheral lymphocytes decreased in patients whose rectal temperature was less than 34.5 degrees C, whereas mitogen response of lymphocytes to PHA and Con-A remained unchanged in patients whose rectal temperature was above 34.0 degrees C. NK cell ratio and cytotoxicity decreased in patients whose rectal temperature was less than 34.5 degrees C, including infectious cases. These results suggested that, under hypothermia therapy, immune responses of the patients whose rectal temperature was less than 34.5 degrees C were disturbed because of the reduced number of peripheral lymphocytes and depression of NK cell activity.

Predictors of deteriorating cerebral infarct: role of inflammatory mechanisms. Would its early treatment be useful?

The development of neurological deterioration in the hours following the stroke onset occurs in somewhat more than 1 in 3 cerebral infarcts and is associated with an increase in morbidity and mortality. This early deterioration (0--48/72 h) entails the conversion of the ischemic penumbra area in an irreversible lesion, a process that is mediated as much by hemodynamic changes in the local cerebral circulation as by biochemical mechanisms. Late neurological deterioration (3--7 days) is more frequently associated with systemic causes. Knowledge of the various clinical, biochemical and imaging markers associated with neurological deterioration is consequently of fundamental importance. For their repercussion in clinical practice, we classify these predictors of deteriorating cerebral infarct into nonmodifiable, modifiable and possibly modifiable. The reduction in cerebral blood flow in a particular cerebral zone causes very early cerebral damage as a consequence of a significant liberation of neuroexcitatory amino acids, followed by an excessive entry of calcium into the interior of cells; this process causes lipid peroxidation, disintegration of the cellular membranes, nuclear destruction and neuronal death. Moreover, ischemia and posterior reperfusion induce an inflammatory response leading to further cellular destruction. It is therefore conceivable that therapeutic interventions aimed at decreasing proinflammatory cytokines and cell adhesion molecules might result in better outcome in this population.

Targeting the central nervous system inflammatory response in ischemic stroke

In experimental models of stroke, inflammation appears to contribute to cerebral ischemic injury. Clinical trials that are aimed at limiting the postischemic inflammatory response, however, have thus far had disappointing results. These clinical failures probably reflect the fact that there has been insufficient preclinical data and inadequate trial design, rather than provide evidence against a role for inflammation in ischemic brain injury.

Human focal cerebral infarctions induce differential lesional interleukin-16 (IL-16) expression confined to infiltrating granulocytes, CD8+ T-lymphocytes and activated microglia/macrophages

Focal cerebral ischemia elicits a strong inflammatory response which readily participates in lipid oxygenation, edema formation, apoptotic cell death and tissue remodeling. Within these conditions, cytokines are key players of cell activation and are crucial for delayed mechanisms of ischemic damage. Mature IL-16 is an immunomodulatory cytokine, exerting CD4 dependent and independent effects and is characterized by chemotactic activity, induction of early gene phosphorylation, stimulation of pro-inflammatory IL-1beta, IL-6, TNFalpha expression in monocytic cells and also modulates apoptosis. We have now analyzed expression of IL-16 in 20 brains of patients following focal cerebral infarctions (FCI, n=20). Compared to normal control brains (n=3), IL-16 was expressed by infiltrating immune cells such as neutrophils, CD8+ lymphocytes and activated CD68+ microglia/macrophages accumulating in lesion associated reactive zones and in peri-vascular regions. IL-16+ cells accumulated significantly (P<0.0001) in the necrotic lesion and at bordering peri-lesional areas at day 1-2 reaching maximum levels at day 3-4 (P<0.0001). Also, peri-vascular IL-16+ cells reached maximum levels at day 3-4 (P<0.0001) following infarction and decreased after several weeks. During the early microglial activation period, IL-16+ microglia/macrophages coexpress the activation antigen MRP-8. The accumulation of IL-16+ granulocytes, IL-16+, CD8+ lymphocytes and activated IL-16+, CD68+, CD4- microglia/macrophages, early after infarction suggest a CD4 independent, paracrine role of IL-16 in the postinjury inflammatory response, such as recruitment and activation of immune cells leading to microvessel clustering and blood-brain barrier disturbance resulting in secondary damage.

Antibody to the alpha4 integrin decreases infarct size in transient focal cerebral ischemia in rats

BACKGROUND AND PURPOSE

Inflammation, a process that involves neutrophils, lymphocytes, and monocytes, contributes to cerebral ischemic injury. Blockade of neutrophil adhesion to endothelium improves outcome after experimental stroke. In this study we sought to assess the contribution of lymphocytes and monocytes to ischemic brain injury.

METHODS

Male Lewis rats underwent 3 hours of middle cerebral artery occlusion followed by 45 hours of reperfusion. Two hours after the onset of ischemia, one group of animals received an intraperitoneal injection of antibodies to the alpha(4) integrin (n=16); another group was injected with an isotype control antibody (n=11). Neurological examination, body temperature, and body weight were assessed at different time points after stroke. Animals were killed 48 hours after the onset of ischemia for determination of infarct volume and leukocyte counts.

RESULTS

There were no significant differences in body temperature or weight at any time. Neurological scores (deficits) were significantly less in animals treated with anti-alpha(4) antibodies at 24 (2.0+/-1.2 versus 3. 0+/-0.4; P:=0.006) and 48 (2.0+/-1.2 versus 3.0+/-0.8; P:=0.011) hours after ischemia. Peripheral blood leukocyte counts were significantly higher in anti-alpha(4)-treated animals (6.8+/-2.2 x 10(9) versus 2.9+/-1.9 x 10(9); P:=0.001) and revealed a lymphocyte/monocyte predominance (86.0+/-16.2% versus 71.0+/-15.6%; P:=0.008). Infarct volume was significantly less in animals treated with antibodies to alpha(4) (120.1+/-51.21 versus 173.7+/-42.29 mm(3); P:=0.012).

CONCLUSIONS

These data support a role for lymphocytes and monocytes in cerebral ischemic injury and show that blockade of alpha(4), even when instituted after the onset of ischemia, can improve neurological outcome and decrease infarct volume.