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(Circulation. 1996;94:939-945.)
© 1996 American Heart Association, Inc.

Articles

Endothelial ICAM-1 Expression Associated With Inflammatory Cell Response in Human Ischemic Stroke

Perttu J. Lindsberg, MD, PhD; Olli Carpen, MD, PhD; Anders Paetau, MD, PhD; Marja-Liisa Karjalainen-Lindsberg, MD; Markku Kaste, MD, PhD

the Department of Neurology (P.J.L., M.K.) and the Department of Pathology (O.C., A.P., M.-L.K.-L.), University of Helsinki (Finland).

Correspondence to Dr P.J. Lindsberg, Department of Neurology, University of Helsinki, Haartmaninkatu 4, FIN-00290 Helsinki, Finland.

	Abstract

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Background After focal brain ischemia, leukocytes adhere to the perturbed endothelium and are believed to aggravate reperfusion injury. Although ischemia-induced upregulation of endothelial adhesion molecules, intercellular adhesion molecule-1 (ICAM-1) and P-selectin, has been observed in experimental animals, the mechanism of cerebral leukocyte infiltration and thus therapeutic possibilities to reduce it in humans are uncertain.

Methods and Results We counted the granulocytes, mononuclear phagocytes, and the percentages of cerebral microvessels expressing ICAM-1 by applying immunohistochemistry on brain sections showing a variable degree of neuronal damage from 11 human subjects who died 15 hours to 18 days after ischemic stroke and from normal control brains. In infarcted regions, granulocytes were detected as early as at 15 hours after injury (11.3 versus 0.5 cells/mm² in noninfarcted hemisphere); their amount exceeded 200 cells/mm² by 2.2 days but was back to normal level at 6.3 and 8.5 days. Acute infarctions (0.6 to 8.5 days) harbored significantly more ICAM-1–stained microvessels (up to 97% of microvessels at 1.8 days) than the noninfarcted hemisphere (P<.001), although the noninfarcted hemisphere (1.8 to 6.3 days) also showed higher ICAM-1 expression than controls. In the absence of ICAM-1 upregulation, macrophages (>200/mm²) were abundant in the core of neuronal damage at 17 and 18 days.

Conclusions The striking upregulation of endothelial ICAM-1 expression, functioning in concert with chemotactic factors, may cause granulocyte infiltration during the first 3 days after stroke. This study may support the usage and timing of antibody infusions to block endothelial adhesion molecules in an attempt to reduce leukocyte-induced damage in stroke.

Key Words: molecular biology • leukocytes • microcirculation • stroke

	Introduction

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As a crucial component of the host response to local ischemia, accumulation of leukocytes has been demonstrated in areas of acute brain infarction in humans and experimental animals.^{1 2 3 4} Actions of leukocytes are believed to aggravate tissue injury after ischemia and reperfusion in myocardium, brain, and other organs.^{5 6 7} A key mechanism of leukocyte-induced brain injury is microcirculatory failure^{8 9} in the form of capillary blocking, blood-brain barrier damage, and vasoconstriction, the biochemical mediators of which include reactive oxygen species, leukotrienes, cytokines, platelet-activating factor, and proteolytic enzymes stemming from interaction between leukocytes and perturbed endothelium in the ischemic area.^{10 11} Following a cascade of molecular steps leading to the recognition of binding sites by a leukocyte rolling on the endothelium, tight adherence must be achieved before leukocytes can become pathogenic.¹² Leukocytes adhere to the endothelium through specific transmembrane glycoproteins, primarily the ß₂-integrin receptor complex CD11a/CD18 (LFA-1), which interacts with its counterreceptor intercellular adhesion molecule-1 (ICAM-1) on the endothelium.^{13 14} Upon activation and strong adherence, the leukocytes flatten and soon undergo diapedesis to enter the parenchyma.¹²

Recent studies have indicated that pharmacological interventions aimed at inhibiting the actions of polymorphonuclear leukocytes can salvage neuronal tissue after ischemia in therapeutic protocols used in experimental animals.^{15 16 17} In addition, depression of the function of mononuclear phagocytes was shown to reduce ischemic damage when treatment was delayed up to 6 hours after reperfusion in rabbits.¹⁸ In line with similar evidence of experimental models of myocardial injury,¹⁹ this work has promising therapeutic possibilities to restrict tissue injury after ischemia and reperfusion. Advances made in unraveling the sequential expression and intricate interaction of the adhesion molecules that regulate leukocyte-endothelium contacts have put antiadhesion therapies among the prime candidates for such attempts.²⁰ Since growing experimental evidence has suggested the suitability of ICAM-1 as a target in blocking leukocyte adhesion and neuronal injury in ischemic brain injury,^{15 21 22 23} large clinical trials based on anti–ICAM-1 therapy in stroke are now being considered.

In view of the clinical implications, we had several compelling reasons to investigate the hypothesis of whether phagocytes are found early in human brain infarction and whether that response is related to changes in the endothelial expression of ICAM-1. Only semiquantitative data exist on the progression of phagocyte infiltration in human stroke,²⁴ and the cerebral ICAM-1 upregulation has been reported only in sporadic stroke cases.²⁵ Since systematic studies of adhesion molecules during the natural course of stroke are lacking, the spatial and temporal evolution of ICAM-1 molecules with respect to infarction and leukocyte infiltration remain unknown and cannot be inferred from experiments with healthy subhuman species. This led us to attempt to clarify these relationships by postmortem investigation of the brains of patients who died as the result of brain infarction or its complications at time points relevant to acute interventions purported to modulate leukocyte actions and emigration.

	Methods

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Patients
We studied autopsy material of 11 patients treated at the Department of Neurology who died soon after the onset of acute ischemic stroke. The immediate causes of death were either stroke-related events (ie, severe brain edema) (n=5), pulmonary embolism (n=4), or cardiac failure (n=2). Autopsies were performed within 16±3 hours (mean±SE) after death. Four patients had an acute infectious disorder (case 6, moderate bronchitis; case 9, cholecystitis; cases 10 and 11, pneumonia). In addition, 3 patients who had died suddenly of nonneurological causes were included as controls. Since chronic stroke risk factors such as hypertension have been suggested to lead to an increase in endothelial ICAM-1 expression,²⁶ control patients with stroke risk factors were chosen to ensure that the results would be specific to the acute infarction and not to any underlying condition. Autopsies of these patients were performed at 14, 14.5, and 11 hours (mean, 13 hours) after death, respectively. Details of patients are given in the Table.

View this table: [in this window] [in a new window]   Table 1. Characteristics of Postmortem-Studied Stroke Patients

Histological Methods
On autopsy, the infarcted brain areas were identified during the macroscopic examination of the brain parenchyma and cerebrovasculature in comparison with the most recent computed tomography scans. Since the localization and size of the infarcts were unique in each case, we preferred to target the tissue sampling on the basis of the individual infarct topography rather than standard localizations. Approximately 1-cm³ cortical samples including subcortical white matter were dissected, frozen in liquid nitrogen, and stored at -70°C until analyzed. Similar specimens were routinely fixed with formaldehyde and embedded in paraffin and cut for hematoxylin-eosin staining. From the frozen tissue blocks, fresh-frozen sections (5 µm) were cut and stained with hematoxylin-eosin to confirm ischemic neuronal changes. Samples from the corresponding areas of the contralateral or noninfarcted hemispheres and from the control brains were processed in a similar way. Fresh-frozen sections were fixed with cold acetone (-20°C) for 10 minutes and rinsed with PBS, pH 7.4. Examination of the hematoxylin-eosin–stained sections to grade the severity of ischemic neuronal changes was performed by a neuropathologist without information of the sample localization and densities of phagocytes and ICAM-1 deposition examined separately from the same tissue blocks. Focusing on the integrity of the nucleus, we ascribed scores for signs of ischemic neuronal changes to each tissue section as follows: 1, largely normal morphology but scattered neurons had nuclear abnormalities such as pyknosis, low nuclear cytoplasmic contrast, or smearing of nuclear border (similar to type III neurons)²⁷ ; 2, a large proportion of neurons had nuclear abnormalities; 3, a large proportion of neurons had nuclear abnormalities while scattered ones exhibited signs of irreversible damage such as shrunken cytoplasm with irregular borders and invisible nuclei (similar to type IV neurons)^{27 28} ; and 4, a large proportion of neurons showed irreversible changes.

Immunocytochemistry
We performed immunohistochemical staining using the advidin-biotin complex/horseradish peroxidase method (Dako). Four antibodies (anti–FVIII-RA, anti-CD34, anti-CD31, and HAM56, [Dako]) were compared in pilot investigations in identification of microvessels in fresh-frozen brain sections and anti-CD31 monoclonal antibody (MAb) (Dako) resulted in the most consistent vessel density. Phagocytes were visualized with a MAb against the CD15 epitope present on granulocytes (Dako) and with HAM56 MAb recognizing the mononuclear phagocytes (Dako). ICAM-1 was detected with UHP-9 MAb.²⁹ The MAb reacts with purified ICAM-1, blocks ICAM-1–dependent cell adhesion to purified LFA-1, and specifically stains COS-1 cells transfected with ICAM-1 cDNA. P-selectin was stained with anti-CD62 MAb (CLB Thromb/6, Immunotech, Marseille, France) and compared with the density of platelets visualized by a MAb-detecting GpIIb/IIIa (10E5).³⁰ x63 MAb (American Type Culture Collection, Rockville, Md) was used as a control primary antibody for all specimens.

Microscopy of Tissue Sections Used in Immunohistochemistry
Although hemorrhagic transformation of the infarction took place only in two cases (1.2 and 4.5 days), areas showing clear erythrocyte extravasation were avoided in the microscopic examination of all brains. Microscopy of the immunohistochemically stained tissue sections was performed by an investigator blinded to the origin and neuronal changes contained in the samples. The density of microvessels in each section was determined by counting all CD31-positive microvessels (minimum transverse diameter <30 µm) in 10 microscopic fields of 0.32 mm² and averaged. The density of ICAM-1–positive microvessels in each section was determined similarly in five representative cortical fields. Capillaries (<7.5 µm) and larger vessels (7.5 to 30 µm) were counted separately. As a semiquantitative grading, a distinction was made between microvessels showing strong ICAM-1 staining (dark red aminoethylcarbazole deposited in vessels, see Fig 1C and 1D) and others showing lighter ICAM-1 staining. Counting of ICAM-1–positive objects was done manually to avoid contamination of ICAM-1–positive vessel counts with other resident or infiltrating cells occasionally expressing ICAM-1. Similarly, an average of cell counts in five representative fields was taken as the density of granulocytes and mononuclear phagocytes in each case. A systematic evaluation of morphological details such as confirmation of whether a granulocyte was still surrounded by or occluding a capillary lumen could not be reached in the fresh-frozen sections. Examination of phagocytes, ICAM-1, and neuronal changes was performed from the same tissue blocks and cortical infarct regions and compared with corresponding areas of tissue blocks dissected from homologous locations of the noninfarcted hemispheres or control brains.

View larger version (145K): [in this window] [in a new window]   Figure 1. Photomicrographs of immunocytochemical staining of cortical tissue sections. A, Normal control brain sections stained with anti-CD31 to visualize all cerebral microvessels; B, some microvessels stained faintly with intercellular adhesion molecule-1 (ICAM-1) antibody (arrowheads) (x230). Representative sections from case 3 studied at 1.6 days after infarction show strongly ICAM-1–positive (solid arrowheads) microvessels in the infarcted area (C) and fewer weakly ICAM-1–positive (open arrowheads) microvessels in the noninfarcted hemisphere (D) (x324). A difference in the stage of granulocyte emigration (case 3; anti-CD15 staining) in the infarcted areas in correlation with the severity of neuronal damage is shown. Typical examples of clusters of intra/perivascular granulocytes (E) in a region of moderately damaged neurons and scattered granulocytes in the neuropil of a region in the infarct core (F) (x345) are shown. Hematoxylin-eosin staining of the corresponding regions demonstrate preservation of the nuclear contour in moderately damaged neurons (G, left field; open arrowhead) and uniformly stained, pyknotic nuclei in severely damaged neurons (G, right field; solid arrowhead) (x430). H, HAM 56 staining of a brain section from case 11 studied at 18 days after infarction demonstrates large amounts of obese macrophages infiltrating in the infarct core (x345).

Statistical Methods
To determine the statistical significance of the observed differences in the fractions of ICAM-1–positive microvessels in the infarcted and noninfarcted hemispheres, the dependent t test was used with Bonferroni correction. Differences were considered statistically significant at P<.05 and highly significant at P<.01.

	Results

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In control brains and noninfarcted hemispheres, the densities of CD31-positive microvessels were 207±13/mm² and 217±10/mm², respectively. Since the densities in the areas of mild/moderate (163±14/mm²) and severe neuronal damage (152±10/mm²) were somewhat lower (probably the result of edema or fragility of the infarcted tissue during freezing and staining procedures), all data of endothelial ICAM-1 expression were expressed as a fraction of the obtained overall microvessel density in the same tissue sample. While phagocyte infiltration was not observed in the three control cases, a minor proportion (mean, 21.7%; range, 11.4% to 35.9%) of cortical CD31-positive microvessels was stained with anti–ICAM-1 (Fig 1A and 1B), and only sporadic microvessels had strong staining (mean, 1.0%; range, 0.2% to 1.6%).

Although the two to four samples dissected from each infarction exhibited variable intensities of ischemic neuronal damage, neurons in one infarction (4.5 days) only received scores 1 and 2, and another (18 days) exhibited only score 4 neurons. Since the ischemic neuronal changes in the centers of more acute infarctions, although not fully matured (score 3), clearly revealed more advanced damage than those in more peripheral samples, scores 3 and 4 were combined into a class of severe damage to represent the infarct cores. On the other hand, since samples from all cases did not exhibit both degrees of mildest neuronal damage (1 and 2), these scores were combined into a class of mild/moderate damage (Figs 2 and 3).

View larger version (28K): [in this window] [in a new window]   Figure 2. Phagocyte counts in brain sections from the infarcted and noninfarcted brain regions of the patients who died at indicated time points after ischemic stroke. Data are arranged according to the degree of neuronal damage in the infarcted hemisphere. Levels of phagocytes in the three control brains without brain injury were negligible and indicated by the arrow. A, Counts of granulocytes visualized by immunocytochemical staining with CD15 antibody. B, Counts of mononuclear phagocytes visualized by immunocytochemical staining with the HAM 56 antibody.

View larger version (36K): [in this window] [in a new window]   Figure 3. Percentages of intercellular adhesion molecule-1 (ICAM-1)-expressing microvessels in infarcted brains. Sections were stained with monoclonal antibody (MAb)-detecting ICAM-1, and the amount of positive microvessels was compared with the number of vessels detected with CD31 MAb in the same sections. Data are arranged according to the degree of neuronal damage in the infarcted hemisphere. Mean±SE of percentages of microvessels with ICAM-1 staining in the three control brains without brain injury are indicated by a line (arrow) and two broken lines. A, Percentages of microvessels with strong ICAM-1 staining. B, Percentages of all microvessels with ICAM-1 staining.

In all brains with hemispheric or posterior circulation infarctions, granulocyte counts were higher than in normal controls in areas of both classes of neuronal damage. The two infarctions of the most acute stage (0.6 and 1.2 days) showed mildly increased numbers of granulocytes, which, however, were >10-fold increased from those in the corresponding contralateral hemispheres. In the most recent infarction (0.6 days), granulocytes still were found mostly within the intravascular space, typically aggregating on the walls of larger microvessels. In a zone of mild neuronal damage (score 1), regions were found where the number of granulocytes was increased 25-fold from that in the contralateral hemisphere. Maximal granulocyte response was found in infarctions of 1.6 to 2.2 days of duration, and it was roughly equal at sites regarded as having mild/moderate and severe neuronal damage. However, in one case (1.6 days), the granulocytes in the core of neuronal damage were found typically scattered through the parenchyma, while they still tended to aggregate in the intravascular space in a surrounding area (Fig 1, E through G). In one infarction caused by basilar artery thrombosis (3.2 days), only a mild degree of granulocyte emigration was detected, which, however, also was the case for infarctions studied at subsequent time points (6.3 and 8.5 days). Ghosts or deposits of presumably granulocyte-derived, CD15-positive debris were observed frequently in the less acute infarctions. Influx of macrophages and phagocytosis of neutrophils prevented reliable counting of granulocytes in the more chronic infarctions (17 and 18 days). Mononuclear phagocytes were found to accumulate in infarctions studied at 4.5 to 8.5 days, while the last two cases (17 and 18 days) had considerable macrophage infiltration (Fig 1H) concentrated in the infarct core. The phagocyte densities in all infarctions are illustrated quantitatively in Fig 2.

ICAM-1 was upregulated on the endothelia of microvessels in infarcted brain (Fig 3). The three most acute infarctions (0.6, 1.2, and 1.6 days) that had mildly or moderately increased granulocyte density expressed approximately twofold increased density of ICAM-1–positive and fourfold to sixfold increased density of strongly ICAM-1–positive microvessels compared with the homologous locations in the noninfarcted hemispheres, in which the endothelial ICAM-1 was expressed as in normal controls. In one infarction core (1.8 days), the ICAM-1 and CD31 antibodies stained almost congruent populations of microvessels, with up to 26% being graded as strongly ICAM-1 positive. Interestingly, although maximal ICAM-1 staining was consistently observed in the infarcted brain, the noninfarcted areas of some cases (1.8 to 6.3 days) also had more ICAM-1–stained microvessels than the control brains. There was no association between endothelial ICAM-1 deposition and the presence of an infectious disorder, which tended to be accumulated in the more matured infarctions. In another matured infarction (6.3 days), the endothelial ICAM-1 expression remained high although the number of CD15-positive granulocytes was very low (Fig 2A and Fig 3). ICAM-1 expression of all cases is expressed quantitatively as a fraction of the number of CD31-positive microvessels in the same areas (Fig 3).

We noted a tendency that in the most acute infarctions, equal proportions of ICAM-1–positive microvessels were <7.5 µm (capillaries) and between 7.5 and 30 µm, while more matured infarctions had substantially more ICAM-1–stained capillaries than larger microvessels (data not shown). Statistical comparisons (dependent t test with Bonferroni correction) between the infarcted and noninfarcted hemispheres of a group (excluding the two least acute cases; 17 and 18 days) of the fractions of microvessels with either moderate or strong ICAM-1 deposition suggested highly significant differences (P<.001 and P<.01, respectively).

Immunoreactivity for P-selectin was observed occasionally in patchy areas in several infarcted brains. This immunoreactivity corresponded to both obvious platelet aggregates and deposits with the shape of vascular structures of various sizes. Since immunoreactivity for the platelet antigen GpIIb/IIIa had similar distribution, further attempts to confirm the origin of P-selectin expression were not made.

	Discussion

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The present clinical investigation demonstrates for the first time on a quantitative basis that cerebral ischemia induces striking expression of endothelial ICAM-1 in temporal and spatial correlation with both neuronal damage and granulocyte emigration in infarcted brain. As early as 15 hours after the insult, up to 25-fold increased granulocyte density was observed, which corresponded to the markedly increased number of microvessels with strong ICAM-1 staining (Fig 3A). This supports early release of endothelial chemotactic factors,¹² which function in concert with localized adhesion molecule upregulation to focus the host response into the infarcted region.

Both granulocyte emigration and ICAM-1 expression in microvessels were further strengthened in infarctions studied at 1 to 2 days up to the point where maximally all visualized microvessels in the damage core expressed ICAM-1 (Figs 2 and 3). During the subsequent 4 days, increased ICAM-1 expression persisted, but granulocyte infiltration ceased. However, the necrotic infarctions of the more chronic phase showing largest macrophage accumulations (Fig 1H) had normal or decreased ICAM-1 expression (Fig 3A and 3B), although the vessel density was comparable to the acute infarctions. While the early granulocyte emigration was similar in areas of mild and severe neuronal damage, the delayed macrophage infiltration appeared to be concentrated more in the damage centers (Fig 2B). Divergent chemotactic and adhesion phenomena seem to call the granulocyte and mononuclear phagocyte responses. Since granulocyte ghosts were found frequently in the proximity of clusters of obese macrophages, mononuclear cells may be merely seduced by signals stemming from senescent granulocytes.³¹

The mechanism of ICAM-1 upregulation on infarcted brain microvessels is unknown at present, but a general response intrinsic to the endothelial cells may be involved. Human cerebral microvessels recently were shown to increase ICAM-1 expression after prolonged hypoxia and reoxygenation, and generation of intracellular free radicals on reoxygenation was suggested to underlie this phenomenon.²² Alternatively, ischemia/reperfusion may influence the release of endothelial mediators such as endothelins or nitric oxide, which could play a role in ICAM-1 upregulation.^{32 33} On the other hand, ICAM-1 expression could be associated with longstanding effects of stroke risk factors on endothelial cells. To this end, tumor necrosis factor- (TNF-), a strong ICAM-1 inducer, has been demonstrated to be released in abnormally large amounts by the vasculature of spontaneously hypertensive rats, a species expressing ICAM-1 on cerebral endothelium more avidly after cytokine stimulation than normotensive rats.²⁶ Furthermore, chronic hypertension is believed to depress endothelial nitric oxide synthesis,^{34 35} a state that also produced upregulation of ICAM-1 in cultures of human endothelial cells.³⁶

Although the increased endothelial ICAM-1 expression in all cases was focused in the infarcted hemisphere, it occurred also in the noninfarcted hemisphere during 1.8 to 6.3 days after infarction (Fig 3A and 3B) in the absence of phagocyte responses. One interpretation of this finding is that strong adhesion-promoting factors³⁷ such as TNF- and interleukin-1 (IL-1) may be first released locally and diffuse further into the cerebrospinal fluid and cerebral extracellular space and lead to increased ICAM-1 expression throughout the brain in the more matured phase. Recent experimental observations suggest that middle cerebral artery occlusion in rodents also induces transient TNF- production in the contralateral hemisphere (Reference 38; also personal communication with Dr Qi-Hui Zhai, February 10, 1995, Charleston, SC). However, we cannot exclude a scenario that in the infarction studied at 1.8 days, a transtentorial herniation, and in two other cases studied at 3.2 and 6.3 days, a slight degree of generalized brain edema could have triggered endothelial ICAM-1 expression through secondary microcirculatory perturbation during increased intracranial pressure. That granulocyte infiltration did not occur in the noninfarcted hemispheres may indicate lack of a sufficient chemotactic gradient. Potent chemotactic agents such as C5a, leukotriene B₄, IL-8, IL-1, platelet activating factor, or TNF-^{39 40} might be released primarily in the injured area. A finding supporting the role of chemotactic complement factors (C5a) was that activation of the terminal complement pathway was observed only in infarcted brain regions.⁴¹

Conclusions
We have demonstrated the evolution of granulocyte emigration at various time points after brain ischemia that correlated to simultaneous, robust upregulation of ICAM-1 expression on cerebral endothelium. This observation is in agreement with the recent findings of transiently increased ICAM-1 expression in baboons after focal ischemia and reperfusion²³ but underscores the more prolonged and generalized nature of this response in the brains of patients who die at the height of the disease. Therefore, the evolution of the host response in healthy experimental animals may be an insufficient basis for clinically oriented therapy protocols. The clinical relevance of the present investigation is further supported by the assumption that in individuals who spontaneously develop cerebrovascular disease, risk factors might have altered the responses of cerebral endothelium, rendering them more vulnerable to the pathological aspects of the host response to acute brain ischemia. All victims of stroke showing endothelial ICAM-1 upregulation in the present investigation clearly represent the (however heterogeneous) cohort, whose lives might have been prolonged with experimental stroke therapies. It remains to be determined whether antagonism of the increased presentation of molecular targets for leukocyte adherence, which we have shown to last for several days after stroke, could provide an effective rationale for acute stroke therapy.

	Acknowledgments

 
This article opens a series of publications designated collectively as the Helsinki Stroke Study (HSS). We thank Tuula Halmesvaara for excellent technical assistance. This study was supported by grants from Helsinki University Central Hospital, the Maire Taponen Foundation, and the Paulo Foundation.

Received August 4, 1995; revision received March 6, 1996; accepted March 13, 1996.

	References

Top Abstract Introduction Methods Results Discussion References

 

1. Pozzilli C, Lenzi GL, Argentino C, Carolei A, Rasura M, Signore A, Bozzao L, Pozzilli P. Imaging of leukocytic infiltration in human cerebral infarcts. Stroke. 1985;16:251-255.[Abstract/Free Full Text]
   
2. Hallenbeck JM, Dutka AJ, Tanishima T, Kochanek PM, Kumaroo KK, Thompson CB, Obrenovitch TP, Contreras TJ. Polymorphonuclear leucocyte accumulation in brain regions with low blood flow during the early postischemic period. Stroke. 1986;17:246-253.[Abstract/Free Full Text]
   
3. Wang PY, Kao CH, Mui MY, Wang SJ. Leukocytic infiltration in acute ischemic stroke. Stroke. 1993;24:236-240.[Abstract/Free Full Text]
   
4. Garcia JH, Liu KF, Yoshida Y, Lian J, Chen S, del Zoppo GJ. Influx of leukocytes and platelets in an evolving brain infarct (Wistar rat). Am J Pathol. 1994;144:188-199.[Abstract]
   
5. Vedder NB, Winn RK, Rice CL, Chi EY, Arfors K-E, Harlan JM. A monoclonal antibody to the adherence-promoting leukocyte glycoprotein, CD18, reduces organ injury and improves survival from hemorrhagic shock and resuscitation in rabbits. J Clin Invest. 1988;81:939-944.
   
6. Weiss SJ. Tissue destruction by neutrophils. N Engl J Med. 1989;320:365-376.[Medline] [Order article via Infotrieve]
   
7. Hallenbeck JM, Dutka AJ. Background review and current concepts of reperfusion injury. Arch Neurol. 1990;47:1245-1254.[Abstract]
   
8. del Zoppo GJ, Schmid-Schonbein GW, Mori E, Copeland BR, Chang C-M. Polymorphonuclear leukocytes occlude capillaries following middle cerebral artery occlusion and reperfusion in baboons. Stroke. 1991;22:1276-1283.[Abstract/Free Full Text]
   
9. Mori E, del Zoppo GJ, Chambers JD, Copeland BR, Arfors K-E. Inhibition of polymorphonuclear leukocyte adherence suppresses no-reflow after focal cerebral ischemia in baboons. Stroke. 1992;23:712-718.[Abstract/Free Full Text]
   
10. Kochanek PM, Hallenbeck JM. Polymorphonuclear leukocytes and monocytes/macrophages in the pathogenesis of cerebral ischemia and stroke. Stroke. 1992;23:1367-1379.[Abstract/Free Full Text]
    
11. Lindsberg PJ, Hallenbeck JM, Feuerstein GZ. Platelet-activating-factor in stroke and brain injury. Ann Neurol. 1991;30:117-129.[Medline] [Order article via Infotrieve]
    
12. Adams D, Shaw S. Leukocyte-endothelial interactions and regulation of leukocyte migration. Lancet. 1994;343:831-836.[Medline] [Order article via Infotrieve]
    
13. Dustin ML, Staunton DE, Springer TA. Supergene families meet in the immune system. Immunol Today. 1988;9:213-215.[Medline] [Order article via Infotrieve]
    
14. Springer TA. Adhesion receptors of the immune system. Nature. 1990;346:425-434.[Medline] [Order article via Infotrieve]
    
15. Bowes MO, Zivin JA, Rothlein R. Monoclonal antibody to the ICAM-1 adhesion site reduces neurological damage in a rabbit cerebral embolism stroke model. Exp Neurol. 1993;119:215-219.[Medline] [Order article via Infotrieve]
    
16. Chen H, Chopp M, Zhang RL, Bodzin G, Chen Q, Ruschke JR, Todd RF III. Anti-CD11b monoclonal antibody reduces ischemic cell damage after transient focal cerebral ischemia in rat. Ann Neurol. 1994;35:458-463.[Medline] [Order article via Infotrieve]
    
17. Lindsberg PJ, Siren A-L, Feuerstein GZ, Hallenbeck JM. Antagonism of neutrophil adherence in the deteriorating stroke model in rabbits. J Neurosurg. 1995;82:269-277.[Medline] [Order article via Infotrieve]
    
18. Giulian D, Robertson C. Inhibition of mononuclear phagocytes reduces ischemic injury in the spinal cord. Ann Neurol. 1990;27:33-42.[Medline] [Order article via Infotrieve]
    
19. Entman ML, Lloyd M, Rossen RD, Dreyer WJ, Anderson DC, Taylor AA, Smith CW. Inflammation in the course of early myocardial ischemia. FASEB J. 1991;5:2529-2537.[Abstract]
    
20. Hogg N. Roll, roll, roll your leukocyte gently down the vein. Immunol Today. 1992;13:113-115.[Medline] [Order article via Infotrieve]
    
21. Clark WA, Madden KP, Rothlein R, Zivin JA. Reduction of central nervous system ischemic injury by monoclonal antibody to intercellular adhesion molecule. J Neurosurg. 1991;75:623-627.[Medline] [Order article via Infotrieve]
    
22. Hess DC, Zhao W, Carroll J, McEachin M, Buchanan K. Increased expression of ICAM-1 during reoxygenation in brain endothelial cells. Stroke. 1994;25:1463-1468.[Abstract]
    
23. Okada Y, Copeland BR, Mori E, Tung M-M, Thomas WS, del Zoppo GJ. P-selectin and intercellular adhesion molecule-1 expression after focal brain ischemia and reperfusion. Stroke. 1994;25:202-211.[Abstract]
    
24. Chuaqui R, Tapia J. Histologic assessment of the age of recent brain infarcts in man. J Neuropathol Exp Neurol. 1993;52:481-489.[Medline] [Order article via Infotrieve]
    
25. Sobel RA, Mitchell ME, Fondren G. Intercellular adhesion molecule-1 (ICAM-1) in cellular immune reactions in the human central nervous system. Am J Pathol. 1990;136:1309-1316.[Abstract]
    
26. Siren A-L, McCarron RM, Liu Y, Spatz M, Feuerstein GZ, Hallenbeck JM. Adhesion receptor expression and perivascular monocyte accumulation in carotid arteries and brains of hypertensive rats. In: Tomita M, Mchedlishvili G, Rosenblum W, Heiss W-D, Fukuuchi Y, eds. Microcirculatory Stasis in the Brain. Amsterdam, Netherlands: Elsevier/North Holland Amsterdam; 1993:169-175.
    
27. Eke A, Conger KA, Anderson M, Garcia JH. Histologic assessment of neurons in rat models of cerebral ischemia. Stroke. 1990;21:299-304.[Abstract/Free Full Text]
    
28. Garcia JH, Mitchem HL, Briggs L, Morawetz R, Hudetz AG, Hazelrig JB, Halsey JH Jr, Conger KA. Transient focal ischemia in subhuman primates: neuronal injury as a function of local cerebral blood flow. J Neuropathol Exp Neurol. 1983;42:44-60.[Medline] [Order article via Infotrieve]
    
29. Tiisala S, Majuri M, Carpen O, Renkonen R. Regulation of the expression of ß₂-integrins and CD43 on myelomonocytic cells: correlation to ICAM-1 dependent adhesion. Scand J Immunol. 1994;39:249-256.[Medline] [Order article via Infotrieve]
    
30. Coller BS, Peerschke EL, Scudder LE, Sullivan CA. A murine monoclonal antibody that completely blocks the binding of fibrinogen to platelets produces a thrombasthenic-like state in normal platelets and binds to glycoproteins IIb and/or IIIa. J Clin Invest. 1983;72:325-331.
    
31. Newman SL, Henson JE, Henson PM. Phagocytosis of senescent neutrophils by human monocyte-derived macrophages and rabbit inflammatory macrophages. J Exp Med. 1982;156:430-442.[Abstract/Free Full Text]
    
32. McCarron RM, Wang L, Stanimirovic DB, Spatz M. Endothelin induction of adhesion molecule expression on human brain microvascular endothelial cells. Neurosci Lett. 1993;156:31-34.[Medline] [Order article via Infotrieve]
    
33. Ma X-L, Weyrich AS, Lefer DJ, Lefer AM. Diminished basal nitric oxide release after myocardial ischemia and reperfusion promotes neutrophil adherence to coronary endothelium. Circ Res. 1993;72:403-412.[Abstract/Free Full Text]
    
34. Mayhan WG, Faraci FM, Heistad DD. Impairment of endothelium-dependent responses of cerebral arterioles in chronic hypertension. Am J Physiol. 1987;253:H1435-H1440.[Abstract/Free Full Text]
    
35. Panza JA, Quyyumi AA, Brush JE Jr, Epstein SE. Abnormal endothelium-dependent vascular relaxation in patients with essential hypertension. N Engl J Med. 1990;323:22-27.[Abstract]
    
36. Niu XF, Smith CW, Kubes P. Intracellular oxidative stress induced by nitric oxide synthesis inhibition increases endothelial cell adhesion to neutrophils. Circ Res. 1994;74:1133-1140.[Abstract/Free Full Text]
    
37. Springer TA. Adhesion molecules in immunity and inflammation. In: Lachmann PJ, Peters DK, eds. Clinical Aspects of Immunology. Boston, Mass: Blackwell; 1993:199-219.
    
38. Zhai Q-H, Futrell N, Wang LC, Chen F-J, Gendelman HE. Cytokine gene expression in acute cerebral infarcts in the rat. Stroke. 1995;26:165. Abstract.
    
39. Rossi AG, Hellewell PG. Mechanisms of neutrophil accumulation in tissues. In: Hellewell PG, Williams TJ, eds. Immunopharmacology of Neutrophils. London, England: Academic Press; 1994:223-243.
    
40. Williams FM. Role of neutrophils in reperfusion injury. In: Hellewell PG, Williams TJ, eds. Immunopharmacology of Neutrophils. London, England: Academic Press: 1994:245-257.
    
41. Lindsberg PJ, Ohman J, Lehto T, Karjalainen-Lindsberg M-L, Paetau A, Wuorimaa T, Carpen O, Kaste M, Meri S. Complement activation in the central nervous system following blood-brain barrier damage in man. Ann Neurol. In press.
    

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