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R Rothlein

Publications and source records attributed to R Rothlein.

At least 37 records · Page 2Linked to original sources
PubMed1995

Differential expression and release of CD54 induced by cytokines.

Intercellular adhesion molecule-1 (ICAM-1, CD54) is upregulated in many cell types stimulated by cytokines. A human hepatoblastoma cell line (C3A, a subclone of HepG2/C3 that is currently being used as a surrogate liver) and human lung adenocarcinoma cells (A549) were stimulated with interleukin-1 beta (IL-1 beta), tumor necrosis factor-alpha (TNF alpha), interferon-gamma (IFN gamma), or IL-6 to determine any differences in cell type responsiveness to individual cytokines for ICAM-1 upregulation. Time courses were performed with each cytokine evaluating ICAM-1 mRNA, surface expression, and cICAM-1 in the cell culture media. Between 3 and 6 hours, IL-1 beta (30 U/mL) stimulated the greatest increase in hepatocyte ICAM-1 mRNA, followed by IFN gamma (100 U/ mL), and IL-6 (100 U/mL) in order of potency. Except for IL-6, cytokine-induced hepatocyte surface levels of ICAM-1 (immunofluorescence flow cytometry, mAb R6.5) were dose dependent, with inhibition at higher concentration. Highest levels followed stimulation with INF gamma (P < .05). Significantly less was found after both IL-1 beta and TNF alpha; none was detected after IL-6 (P < .05). In contrast, IL-1 beta stimulated significantly more cICAM-1 release from hepatocytes than the other cytokines (P < .001), and IL-6 stimulated modest cICAM-1. Between 3 and 6 hours in the A549 cells, IL-1 beta stimulated the greatest increase in ICAM-1 mRNA, followed by TNF alpha. Both responses were greater than that observed in the hepatocytes. IFN gamma- and IL-6-induced ICAM-1 mRNA synthesis was not different from unstimulated A549 cells. Cytokine-induced A549 surface levels of ICAM-1 (immunofluorescence flow cytometry, mAb R6.5) was highest for IL-1 beta (peak levels similar to hepatocyte response), modest with TNF alpha (peak levels less than hepatocytes), detectable with IFN gamma (much less than hepatocytes), and nondetectable after IL-6. No ICAM-1 release from A549 cells was induced under any condition. In hepatocytes the amount of ICAM-1 mRNA was best accounted for by considering both cell surface levels of ICAM-1 and cICAM-1 levels. In human lung adenocarcinoma cells, the cytokine induction of ICAM-1 mRNA could potentially be accounted for by observing cell surface levels of ICAM-1 because no cICAM-1 was produced. These results suggest that surface ICAM-1 and cICAM-1 may be differentially controlled by each cytokine and by each parenchymal cell type.

Adenocarcinoma↗
PubMed1994

Inhibition of transplant rejection by pretreatment of xenogeneic pancreatic islet cells with anti-ICAM-1 antibodies.

Cognate recognition of antigen-presenting cells by antigen-specific T cells is critically dependent on non-cognate adhesive interactions. For instance, several studies have shown that in vivo anti-LFA-1 plus anti-ICAM-1 mAb treatment results in prolongation of allograft survival. We have developed a xenogeneic islet transplant model to investigate the role of various adhesion interactions in the xenogeneic response and study the effect of pretreating donor tissue with immunosuppressive drugs. Pancreatic islet cells were pretreated in vitro with anti-human ICAM-1 mAb, transplanted under the renal capsule of diabetic B6 mice in the absence of systemic immunosuppression and examined for long-term xenograft acceptance. The survival of human islets pretreated with anti-human ICAM-1 was significantly prolonged (MST = 53 days, with 40% of grafts surviving > 100 days). In contrast, the survival of human islets pretreated with the control antibody was similar to those of nontreated islets (MST = 7 days). A massive lymphocyte infiltrate into control xenografts was observed at 5 days post-transplant. In contrast, a lymphocyte infiltrate did not appear in the anti-ICAM-1-treated islets for at least 11 days. Only mAbs specific for the LFA-1 binding epitope of ICAM-1 were found to inhibit a mixed islet/lymphocyte reaction in vitro and block graft rejection in vivo. However, graft prolongation is not accompanied by systemic tolerance. Mice transplanted simultaneously with human islet cells treated with control Ig (left kidney) or anti-ICAM-1 (right kidney) rejected the control islets but not anti-ICAM-1-treated islets. These results suggest that the LFA-1/ICAM-1 interaction is a critical component for xenograft rejection and, more important, that pretreatment of islet tissue with anti-adhesion molecule antibodies can profoundly alter graft recognition and rejection in the absence of any systemic drug therapy. However, graft prolongation is not accompanied by systemic tolerance induction.

Animals↗
PubMed1994

Isotype choice for chimeric antibodies affects binding properties.

Construction of a series of chimeric antibodies (murine variable region and human constant region) derived from the murine antibody BIRR1, which recognizes intercellular adhesion molecule 1 (ICAM-1), has revealed differences in the relative binding abilities of the chimeric antibody to antigen. The chimeric antibodies show a ranking of their ability to compete with BIRR1 for antigen on the surface of cells with the order BIRR1 = cIgG1 (100%) > cIgG4 (30%) > cIgG2 (10%) as demonstrated by solid-phase competitive enzyme-linked immunosorbent assay. Papain digestion yielded Fab fragments that were purified to homogeneity. Competitive enzyme-linked immunosorbent assay showed that the chimeric and murine Fab binding constants were equivalent. A solution-phase binding assay (analyzed by size exclusion high performance liquid chromatography) between the intact mAbs and recombinant soluble ICAM-1 further established that the binding constants involving the Fab arms of the two antibodies were equivalent. In summary, the murine and chimeric anti-ICAM-1 antibodies bind cellular ICAM-1 with equivalent affinities but with differing avidities.

Animals↗
PubMed1994

Cross-linking of ICAM-1 induces co-signaling of an oxidative burst from mononuclear leukocytes.

Cell adhesion molecules were first described as accessory molecules simply to bridge one cell to another. More recently, it has been realized that these molecules also transmit signals from outside of the cell to inside. We show that cross-linking of the ICAM-1 on the cell membrane with anti-ICAM-1 mAb and F(ab')2 fragments of goat anti-MIgG in the presence of suboptimal levels of the bacterial peptide FMLP results in co-stimulation of an oxidative burst from CD14 expressing PBMCs. The amplitude of the oxidative response was less than the oxidative burst induced by CD18 cross-linking, whereas the response was more prolonged. On the other hand, cross-linking by anti-L-selectin mAb plus F(ab')2 fragments of goat anti-MIgG induced a minimal oxidative burst that was not significantly greater than the response generated by anti-L-selectin mAb alone. The addition of an excess of soluble ICAM-1 to compete for the anti-ICAM-1 mAb inhibits the oxidative burst in response to ICAM-1 cross-linking but not to CD18 cross-linking. These results suggest that ICAM-1 is capable of delivering a transmembrane signal into CD14-positive PBMC.

Animals↗
PubMed1994

Treatment of refractory rheumatoid arthritis with a monoclonal antibody to intercellular adhesion molecule 1.

OBJECTIVE: To assess the safety and efficacy of a monoclonal antibody (MAb) to intercellular adhesion molecule 1 (ICAM-1; CD54) in rheumatoid arthritis (RA). METHODS: A phase I/II, open-label, dose-escalation study of 32 patients. RESULTS: During treatment, a peripheral CD3+/CD4+ lymphocytosis was noted, and several patients demonstrated transient cutaneous anergy, which suggests that therapy modified T cell recirculation. Thirteen of the 23 patients who received 5 days of treatment demonstrated clinical improvement through day 29, and 9 of 23 through day 60. Adverse effects were minor and transient. CONCLUSION: Anti-ICAM-1 MAb therapy was well tolerated, resulted in a transient alteration in T lymphocyte recirculation, and effected clinical improvement in some RA patients.

Adult↗
PubMed1994

Mechanisms of polymorphonuclear leukocyte mediated peritoneal mesothelial cell injury.

To determine the susceptibility of human peritoneal mesothelial cells to injury mediated by activated polymorphonuclear leukocytes (PMNs), we exposed cultured human peritoneal mesothelial cells to 1250, 2500, 3750, and 5000 PMNs/mm3 activated with 50 ng/ml phorbol myristate acetate (PMA) or with 10(-7) FMLP/cytochalasin B for one to five hours. PMN adhesion to mesothelial cells was determined with radiolabeled PMNs. Mesothelial cell injury was determined in five different cell lines by measuring ATP depletion and 51chromium release. In each mesothelial cell line, PMN adhesion was significantly (P < 0.001) increased when PMNs were activated; 64 +/- 1.0 to 92.5 +/- 7.0% of the activated PMNs were adherent to mesothelial cells compared to 6 +/- 1.8 to 27 +/- 2.4% of resting PMNs. Mesothelial cells responded to PMN mediated injury with a fall in ATP levels and 51chromium release that was significant (P < 0.05) by three to four hours. At five hours, ATP levels were markedly depressed to 5 to 41% of control values. Increasing concentrations of activated PMNs caused significantly (P < 0.05) greater mesothelial cell injury as determined by ATP depletion and 51chromium release. PMN adhesion, ATP depletion and 51chromium release were significantly (P < 0.01) prevented by an anti-CD18 monoclonal antibody that inhibits the CD11/CD18 adhesion molecule complex on PMNs. Similar injury and protection from injury was demonstrated when mesothelial cells were exposed to PMNs activated with FMLP/cytochalasin B.(ABSTRACT TRUNCATED AT 250 WORDS)

Bacteria↗
PubMed1993

Increased levels of circulating intercellular adhesion molecule 1 in the sera of patients with rheumatoid arthritis.

OBJECTIVE: We sought to assess whether circulating levels of intercellular adhesion molecule 1 (ICAM-1) in patients with rheumatoid arthritis (RA) are elevated and correlate with clinical measures of disease activity and whether this ICAM-1 originates from the synovium. METHODS: Circulating ICAM-1 (cICAM-1) levels were determined by sandwich enzyme-linked immunosorbent assay of serum from 61 RA, 18 osteoarthritis (OA), and 11 inflammatory arthritis (IA) patients. In addition, paired serum and synovial fluid samples were collected from 17 RA, 9 OA, and 4 IA patients. The stability of cICAM-1 was assessed by overnight incubation at 37 degrees C. Finally, the potential degradative effects of synovial fluid proteases were assessed by incubation of recombinant soluble ICAM-1 with patient synovial fluid. RESULTS: RA sera contained significantly greater (P < 0.001) levels of cICAM-1 compared with RA synovial fluid and compared with sera or synovial fluid from the OA and IA patients. Circulating ICAM-1 levels were unaffected by overnight incubation at 37 degrees C and were unaffected by exposure to RA, OA, or IA synovial fluid. Serum levels of cICAM-1 demonstrated a weak, but significant (P < 0.05) correlation with the joint score and erythrocyte sedimentation rate in 25 RA patients treated with nonsteroidal antiinflammatory drugs. CONCLUSION: The greatest elevations of cICAM-1 were seen in RA patient sera. In both RA and OA, synovial fluid cICAM-1 levels were consistently lower than serum levels, suggesting that cICAM-1 did not originate in the synovium. Because the production of cICAM-1 can be increased by cytokines (e.g., interleukin-1, tumor necrosis factor alpha), elevated levels of circulating ICAM-1 in RA may be reflective of systemic exposure to elevated cytokine levels.

Aged↗
PubMed1993

Monoclonal antibody to the ICAM-1 adhesion site reduces neurological damage in a rabbit cerebral embolism stroke model.

We evaluated the effect of antibodies directed against a leukocyte adhesion molecule (ICAM-1) in an embolic model of stroke followed by thrombolysis with tissue plasminogen activator (tPA). To test whether reperfusion injury after ischemia was related to white cell adhesion, microclots were injected into carotid circulation. The conditions examined were control, alpha-ICAM 5 min following ischemia, tPA 30 min after ischemia, and the combination of alpha-ICAM and tPA. alpha-ICAM and tPA both increased the amount of clot necessary to produce permanent neurological damage. Combined therapy was no more effective than either substance alone. A similar outcome was obtained when tPA was delayed until 90 min postischemia. When thrombolysis was delayed 3 h following embolism, neither tPA nor the tPA/alpha-ICAM combination reduced neurological damage. Thus, the alpha-ICAM antibody and tPA each effectively reduced neurological damage but the interaction was not significant.

Animals↗
PubMed1993

Immuno-electron microscopic analysis of the distribution of ICAM-1 in human inflammatory tissue.

An immuno-electron microscopic analysis was undertaken to determine ICAM-1 expression on vascular endothelium in human tonsils and in synovia from patients with rheumatoid arthritis. ICAM-1 was preferentially expressed on high endothelial venules (HEV) located in the parafollicular regions of the tonsils and HEV located in the villous processes of the synovia. On both tissues, these areas contained the greatest number of perivascular lymphocytes. In contrast, ICAM-1 was only weakly expressed on the low endothelium lining capillaries, venules and sinusoids. In both tonsils and synovia, ICAM-1 was confined to the luminal and lateral surfaces of the endothelial cells and absent from the abluminal surfaces adjacent to the basement membrane. We propose that in inflammatory tissues, ICAM-1 mediates the interaction of circulating lymphocytes with the high endothelial cells, but may not have a major role in promoting their migration through the whole thickness of the blood vessel wall.

Arthritis, Rheumatoid↗
PubMed1993

Circulating intercellular adhesion molecule-1 in amniotic fluid, maternal serum alpha-fetoprotein levels, and intrauterine growth retardation.

OBJECTIVE: Our purpose was to determine if circulating intercellular adhesion molecule-1, a marker of chronic inflammation, is present in amniotic fluid in midtrimester, is increased in patients with elevated maternal serum alpha-fetoprotein level, and is associated with intrauterine growth retardation. STUDY DESIGN: Amniotic fluid circulating intercellular adhesion molecule-1 levels were assayed by enzyme-linked immunoassay in 273 samples obtained by midtrimester amniocentesis in gestations involving a single, structurally normal fetus. The control group consisted of 108 patients with normal maternal serum alpha-fetoprotein levels and 165 patients with elevated levels. Intrauterine growth retardation was diagnosed if birth weight was < 10th percentile for the clinically estimated gestational age. RESULTS: Circulating intercellular adhesion molecule-1 was detectable in amniotic fluid in 105 of 273 samples (38%). In the control group it was detectable in amniotic fluid in seven of 108 (6%). In patients with elevated maternal serum alpha-fetoprotein 97 of 164 (59%) had detectable levels (p < 0.001). Of the 273 cases 38 (14%) had intrauterine growth retardation. Of these 23 (59%) had detectable circulating intercellular adhesion molecule-1 levels (p < 0.001). Of the seven cases of intrauterine growth retardation with normal maternal serum alpha-fetoprotein levels, one (14%) had detectable circulating intercellular adhesion molecule-1. Of the 31 cases of intrauterine growth retardation with elevated maternal serum alpha-fetoprotein 22 (71%) had detectable circulating intercellular adhesion molecule-1. When circulating intercellular adhesion molecule-1 was detectable in amniotic fluid, increasing levels was significantly related to decreasing gestational age at delivery (p < 0.005). CONCLUSIONS: Midtrimester amniotic fluid from normal pregnancies does not generally contain detectable circulating intercellular adhesion molecule-1. Detectable amniotic fluid levels are significantly related to a birth weight < 10th percentile at delivery and to elevated midtrimester maternal serum alpha-fetoprotein levels. Increasing circulating intercellular adhesion molecule-1 levels are related to shortened length of gestation. This test may contribute to risk assessment for intrauterine growth retardation and prematurity. Circulating intercellular adhesion molecule-1 is a known marker of inflammatory processes; its further study may also improve understanding of the pathophysiologic mechanisms of certain cases of intrauterine growth retardation and prematurity.

Amniotic Fluid↗
PubMed1993

Circulating intercellular adhesion molecule-1 levels and neutrophil adhesion in stroke.

To examine whether changes in leukocyte adhesion properties occur during stroke, we measured circulating serum intercellular adhesion molecule 1 (cICAM-1) levels and neutrophil adhesion in acute stroke, patients at high risk of stroke, and in matched controls. Levels of cICAM-1 were significantly lower in the stroke group (186.2 +/- 15.6 ng ml-1) compared to controls (257.7 +/- 24.8) and risks (257.7 +/- 16.5). Neutrophil adhesion was significantly higher in the stroke group (23.6 +/- 4.3%; n = 14) compared to controls (9.7 +/- 2.3%; n = 12) and risks (12.7 +/- 2.5%; n = 13). These data suggest that changes in leukocyte adhesion dynamics are occurring in acute stroke.

Cell Adhesion↗
PubMed1993

Detection of circulating intercellular adhesion molecule-1 after liver transplantation--evidence of local release within the liver during graft rejection.

The adhesion molecule ICAM-1 mediates leucocyte adhesion to target structures and other immune cells by binding with the leucocyte adhesion receptors LFA-1 and MAC-1. During rejection of human liver transplants there is increased expression of ICAM-1 on target structures such as bile ducts and venous endothelium and also on lymphocytes infiltrating the graft. Recent reports suggest that a soluble, functionally active form of ICAM-1 designated circulating ICAM-1 (cICAM-1) is released by activated lymphocytes and might be an important mechanism for modulating lymphocyte adhesion and the inflammatory process. We detected cICAM-1 in bile and serum after liver transplantation using an enzyme-linked immunosorbent assay. Serum cICAM-1 was elevated early in the course of acute rejection and appeared at the same time as the soluble interleukin-2 receptor, a marker of lymphocyte activation. Serum levels, however, were not specific for rejection since they were also elevated in infective complications. In contradistinction, biliary levels of cICAM-1 were only elevated in rejection and appeared to be due to local release/secretion within the liver. These data demonstrate that cICAM-1 is released within the liver during graft rejection, probably from activated lymphocytes, and support previous studies that suggested that factors in bile reflect immunological activity within the liver graft more closely than serum factors.

Bile↗
PubMed1993

A phase I trial of immunosuppression with anti-ICAM-1 (CD54) mAb in renal allograft recipients.

Several adhesion molecules contribute to the interaction between T cells and antigen presenting cells or target cells. Leukocyte function-associated molecule-1 (LFA-1[CD11a/CD18]) and intercellular adhesion molecule-1 (ICAM-1 [CD54]) are one such critical adhesive receptor-counter-receptor combination. The importance of ICAM-1 dependent adhesion in the rejection response was initially demonstrated in cynomolgus renal allograft recipients treated with the anti-ICAM-1 murine monoclonal antibody BIRR1. BIRR1 also appeared to limit ischemic damage in these animals. A Phase I clinical trial has subsequently been completed in 18 patients who received cadaver donor renal allografts at high risk for delayed graft function (prolonged preservation time, highly-sensitized recipient). An adequate BIRR1 serum level was associated with significantly less delayed graft function (P < .01) and rejection (P < .01). In 1-hr biopsies, mouse IgG was detected along the endothelium of the vessels and glomeruli in the graft. There were no instances of primary non-function (PNF), and current allograft survival (followup: 16-30 months) in these "high-risk" mAb-treated patients is 78%. There were 3 instances of PNF and a graft survival rate of 56% in the recipients of the contralateral kidney allografts treated with conventional immunosuppression. No significant "first-dose" effect was associated with BIRR1 administration. These results establish a dosing schedule and the clinical safety of BIRR1. They also suggest that inhibition of leukocyte adhesion by mAb therapy may be useful in controlling allograft rejection and possibly in limiting reperfusion injury. Thus, these observations support the clinical importance of accessory molecules in T cell function. We hypothesize that anti-CD54 mAb acts by blocking leukocyte adhesion to the endothelium, thereby interfering with sensitization or target cell interaction.

Adolescent↗
PubMed1993

Leukocyte CD18 monoclonal antibody worsens endotoxemia and cardiovascular injury in canines with septic shock.

We investigated the effects of a murine monoclonal antibody directed against the canine leukocyte CD11/18 adhesion complex (MAb R15.7) in a canine model of septic shock. Awake 2-yr-old purpose-bred beagles were studied 7 days before and 1, 2, 4, and 10 days after intraperitoneal placement of an Escherichia coli-infected fibrin clot. Starting 12 h before clot placement, animals received 0.5-1 mg/kg iv every 12 h (4 doses total) of either MAb R15.7 (MAb group, n = 8) or, as controls, murine serum protein (n = 8). After infected clot placement, all animals received antibiotic (ceftriaxne, 100 mg.kg-1.day-1 for 4 days). Two of eight control animals and four of eight MAb animals died (P = 0.4). During the first 8 h after clot placement, MAb animals, compared with control animals, had greater (P < 0.06) increases in serum endotoxin levels and higher (P < 0.05) neutrophil counts. Day 1 after clot placement, MAb animals, compared with control animals, had decreased (P < 0.05) central venous pressure and arterial pH and increased (P < 0.05) arterial lactate. Day 2 after clot placement, MAb animals, compared with control animals, had decreased (P < 0.05) cardiac index and mean arterial pressure. In summary, MAb R15.7, although associated with increased neutrophil counts, worsened serum endotoxemia, acidosis, and cardiovascular function in this canine model of septic shock. These data suggest that in septic shock, antibody directed against this leukocyte membrane protein complex may be harmful, possibly via impairment of normal leukocyte function.

Acid-Base Equilibrium↗
PubMed1993

Generation and characterization of an anti-idiotypic antibody specific for intercellular adhesion molecule-1.

Intercellular adhesion molecule-1 (ICAM-1) is an inducible ligand for the LFA-1/MAC-1 family of leukocyte adhesion molecules. The results reported herein show that a mouse monoclonal anti-idiotypic antibody, CA3, specific for R6.5 anti-ICAM-1 mAb, shares conformational homology with the original epitope bound by R6.5. The CA3 bound specifically to R6.5 F(ab) fragments and blocked the binding of R6.5 to its ICAM-1 epitope; no CA3 binding was detected to a second anti-ICAM-1 mAb F(ab) fragment nor to control mouse IgG F(ab) fragments. Similarly, the interaction of CA3 with R6.5 was inhibited by sICAM-1. However, CA3 was ineffective in inhibiting CD18-dependent cell aggregation. A rabbit anti-CA3 response (Ab3) further indicated that CA3 is of the Ab2 beta type. Significant binding of anti-CA3 to sICAM-1 was demonstrated and anti-CA3 competed with R6.5 for binding to sICAM-1. Anti-CA3 bound to both soluble and cell-surface-associated ICAM-1. However, unlike R6.5, significant binding both to reduced sICAM-1 and to native sICAM-1 was exhibited by anti-CA3, whereas the binding of R6.5 to reduced sICAM-1 was undetectable.

Animals↗
PubMed1992

Amelioration of antigen-induced arthritis in rabbits treated with monoclonal antibodies to leukocyte adhesion molecules.

OBJECTIVE: To examine the effects of treatment of antigen-induced arthritis in rabbits with a monoclonal antibody against CD18, the common beta chain of the leukocyte adhesion molecules. Intraarticular injection of antigen into primed rabbits elicits an acute inflammatory response followed by chronic arthritis in this model. METHODS: Anti-CD18 was given at the time of intraarticular antigen administration, and effects on the acute and chronic arthritis were investigated. Twenty-four rabbits were examined (11 controls, 3 receiving normal mouse IgG, and 10 receiving anti-CD18). RESULTS: Flow cytometry of blood leukocytes at anti-CD18 administration showed saturating amounts of mouse Ig coating all the circulating cells. Treatment effects on the acute arthritis (measured by quantitating the synovial cell exudate 24 hours after arthritis induction) were a profound reduction in the number of inflammatory cells and a striking decrease in the proportion of polymorphonuclear leukocytes recovered from the synovial cavity, indicating a decrease in acute inflammation. Treatment effects on the chronic synovitis (2 and 4 weeks later) compared with controls showed a significant decrease in synovial fluid cell counts at 2 weeks (1.7 versus 21.0 x 10(6)/joint, P less than 0.03) and at 4 weeks (7.4 versus 22.6 x 10(6)/joint, P less than 0.05). Histologic evaluation of the synovium (0-3+ scale, scored "blindly") of anti-CD18-treated rabbits and controls showed marked decreases in subsynovial cell infiltration and lymphoid follicle formation both at 2 weeks (1.0 versus 2.25, P less than 0.005; and 0 versus 1.75, P less than 0.001) and at 4 weeks (1.48 versus 2.17, P less than 0.01; and 0.75 versus 2.08, P less than 0.02). Quantitation of cartilage-bound immune complexes, and of synovial synthesis of Ig and specific antibody showed no differences between groups. CONCLUSION: These findings indicate that treatment with monoclonal antibody to CD18 not only modifies the initial acute arthritis, but also results in significant amelioration of the subsequent chronic inflammation in this animal model of rheumatoid arthritis.

Animals↗