Functional characteristics of the intercellular adhesion molecule-1 (CD54) expressed on cytotoxic human blood lymphocytes

Natural Killer Cell Receptors and Cytotoxic Activity in Phosphomannomutase 2 Deficiency (PMM2-CDG)

Background

PMM2-CDG is the most common N-glycosylation defect and shows an increased risk of recurrent and/or severe, sometimes fatal, infections in early life. We hypothesized that natural killer (NK) cells, as important mediators of the immune response against microbial pathogens and regulators of adaptive immunity, might be affected in this genetic disorder.

Objective

To evaluate possible defects on PMM2-CDG NK peripheral blood cell number, killing activity and expression of membrane receptors.

Methods

We studied fresh and activated NK cells from twelve PMM2-CDG cells. The number and expression of lymphoid surface receptors were studied by flow cytometry. The NK responsiveness (frequency of degranulated NK cells) and killing activity against K562 target cells was determined in the NK cytotoxicity assay.

Results

We found an increase of blood NK cells in three patients with a severe phenotype. Two of them, who had suffered from moderate/severe viral infections during their first year of life, also had reduced T lymphocyte numbers. Patient activated NK cells showed increased expression of CD54 adhesion molecule and NKG2D and NKp46 activating receptors. NKp46 and 2B4 expression was inversely correlated with the expression of NKG2D in activated PMM2-CDG cells. Maximal NK activity against K562 target cells was similar in control and PMM2-CDG cells. Interestingly, the NK cell responsiveness was higher in patient cells. NKG2D and specially CD54 increased surface expression significantly correlated with the increased NK cell cytolytic activity according to the modulation of the killer activity by expression of triggering receptors and adhesion molecules.

Conclusions

Our results indicate that hypoglycosylation in PMM2-CDG altered NK cell reactivity against target cells and the expression of CD54 and NKG2D, NKp46 and 2B4 activating receptors during NK cell activation. This suggests a defective control of NK cell killing activity and the overall anti-viral immune response in PMM2-CDG patients. The present work improves our understanding of the immunological functions in PMM2-CDG and possibly in other CDG-I types.

Depolymerization of Actin Filament by Cytochalasin E Induces Interleukin-8 Production and Up-Regulates CD54 in the HeLa Epithelial Cell Line

We previously reported that the depolymerization of actin filament by cytochalasin E enhances low affinity Fcepsilon receptor II (CD23) expression on the human monocyte-like cell line, U937 (J. Clin. Immunol. 20: 235, 2000). In this study, we found that cytochalasin E strongly induces interleukin-8 through an epithelial cell line, HeLa, in dose- and time-dependent manners as assessed by enzyme-linked immunoassay and reverse transcription-polymerase chain reaction techniques. In addition, interleukin-8 production in the HeLa cells cultured with cytochalasin E was blocked in the presence of protein kinase C inhibitors, Go6976 and H-7. On the other hand, it was found that CD54 (intercellular adhesion molecule-1; ICAM-1) expression on the HeLa cells and the secretion of soluble CD54 were significantly up-regulated after culturing with cytochalasin E, and that these up-regulations of CD54 were also suppressed by Go6976. Taken together, these findings indicate that cytochalasin E activates protein kinase C under the depolymerization of actin filament, leading to the induction of interleukin-8 production and the up-regulation of CD54 in HeLa cells.

Expression of intercellular adhesion molecule-1 and e-selectin in gastric cancer and their clinical significance

Purpose

Among cell adhesion molecules, serum levels of intercellular adhesion molecule-1 and E-selectin are known to be correlated with the metastatic potential of gastric cancer. In the present study, the authors investigated the expression of intercellular adhesion molecule-1 and E-selectin in gastric cancer tissues and cultured gastric cancer cells, and examined their clinical value in gastric cancer.

Materials and Methods

The protein was extracted from gastric cancer tissues and cultured gastric cancer cells (MKN-28 and Kato-III) and the expression of intercellular adhesion molecule-1 and E-selectin was examined by western blotting. The clinical significance of intercellular adhesion molecule-1 and E-selectin was explored, using immunohistochemical staining of specimens from 157 gastric cancer patients.

Results

In western blot analysis, the expressions of intercellular adhesion molecule-1 in gastric cancer tissues and cultured gastric cancer cells were increased, however, E-selectin in gastric cancer tissues and cells were not increased. Among 157 gastric cancer patients, 79 patients (50%) were intercellular adhesion molecule-1 positive and had larger tumor size, an increased depth of tumor invasion, lymph node metastasis and perineural invasion. The intercellular adhesion molecule-1 positive group showed a higher incidence of tumor recurrence (40.5%), and a poorer 3-year survival than the negative group (54.9 vs. 85.9%, respectively).

Conclusions

Intercellular adhesion molecule-1 is overexpressed in gastric cancer tissues and cultured gastric cancer cells, whereas E-selectin is not overexpressed. Increased expression of intercellular adhesion molecule-1 in gastric cancer could be related to the aggressive nature of the tumor, and has a poor prognostic effect on gastric cancer.

Upregulation of ICAM-1 expression in the conjunctiva of patients with chronic graft-versus-host disease

PURPOSE

To correlate conjunctival intercellular adhesion molecule 1 (ICAM-1) expression with cytologic and clinical findings of chronic graft-versus-host disease (GVHD).

METHODS

Seven patients with chronic GVHD-related keratoconjunctivitis and five age-matched normal controls were recruited for the study. Clinical examination included medical history, visual acuity, evaluation of ocular signs and symptoms (scored from 0 to 3), corneal fluorescein staining (scored from 0 to 5 on the basis of the number of corneal sectors involved), Schirmer test type I, and break-up time (BUT). Impression cytology samples were collected from the nasal and inferior bulbar conjunctiva of patients and controls. Goblet cells were counted in three randomly selected fields and averaged. Immunofluorescent staining for ICAM-1 was carried out and the percentage of cells expressing the marker was evaluated.

RESULTS

All patients showed signs and symptoms of keratoconjunctivitis sicca. Schirmer test type I and BUT were reduced (4.8+/-6.7 mm/5 min and 3.9+/-2.7 seconds, respectively). Goblet cells were significantly reduced in GVHD eyes with respect to normal eyes (65+/-30.5 and 192+/-16.9 cells/field respectively; p<0.001). Goblet cell number was directly related to Schirmer test values (p<0.01, rho=0.817) and inversely related to total sign score (p<0.01, rho=-0.939). ICAM-1 expression was increased in GVHD eyes with respect to normal controls, in which no staining was observed. ICAM-1 expression showed an inverse relation to goblet cell number (p<0.01, rho=-0.852) and Schirmer test values (p<0.01, rho=-0.926), and was directly correlated to total sign score (p<0.01, rho=0.982).

CONCLUSIONS

Conjunctival ICAM-1 expression is increased in GVHD patients. The severity of the disease is associated with tear parameters, goblet cell decrease, and inflammatory markers, such as ICAM-1.

Transactivation of the ICAM-1 gene by CD30 in Hodgkin's lymphoma

The ICAM-1/LFA-1 complex mediates cell-cell interaction. ICAM-1 is overexpressed in Hodgkin/Reed-Sternberg (H/RS) cells, and serum levels of its soluble form are higher in Hodgkin's lymphoma (HL) patients than in controls. There are no data, however, regarding the regulation of expression of ICAM-1 in H/RS cells. CD30 was identified in H/RS cells of HL and has attracted much interest as a molecular marker of HL. To analyze ICAM-1 expression in H/RS cells, we examined the expression of ICAM-1, LFA-1, CD30 and CD30L in HL-derived cell lines. All cell lines expressed ICAM-1 and CD30, but not LFA-1 or CD30L. CD30 induced ICAM-1 expression. Analysis of the ICAM-1 promoter showed the importance of NF-kappaB binding site for CD30-induced ICAM-1 gene expression. Coexpression of IkappaB, IKK, NIK and TRAF dominant-negative constructs with CD30 inhibited CD30-induced activation of ICAM-1 promoter, suggesting that CD30 induces ICAM-1 via NF-kappaB signalling. The ICAM-1 promoter was activated by the C-terminal region of CD30, which activated NF-kappaB signalling. A decoy CD30 lacking the cytoplasmic region inhibited ICAM-1 promoter activity in HL cell lines. Thus, in H/RS cells, ligand-independent activation of CD30 signalling activates NF-kappaB and this leads to constitutive ICAM-1 expression, suggesting a link between 2 well known phenotypic characteristics of HL, CD30 and ICAM-1 overexpression.

Regulation of lymphocyte clustering by CD30-mediated ICAM-1 up-regulation

CD30 is expressed transiently on activated B and T lymphocytes and constitutively on several B- and T cell lymphomas. CD30 functions include participation in negative selection of thymocytes, costimulation of activated T cells, isotype switching of B cells, and regulation of the effector activity of cytotoxic lymphocytes. Although CD30 is not a marker for T helper 2 (TH2) cells, it may participate in the polarization of TH1 and TH2 cells. The pleiotropic functions of CD30 are initiated by interaction of CD30-expressing cells with other immune competent cells expressing CD30-L and providing the signals for modulation of effector cell activity. Here, we report that CD30 signals generated by anti-CD30 on activated, normal murine T cells strongly up-regulate the expression of intercellular adhesion molecule 1 (ICAM-1, CD54), and to a lesser extent, ICAM-2 (CD102). CD30 signals moreover delay the subsequent decline of ICAM expression. CD30 cross-linking did not alter the expression of CD11a/CD18 (LFA-1), the counter receptor for ICAM abundant on T cells. CD30-mediated ICAM-1 up-regulation is independent of cytokine secretion and appears to be transmitted directly through NF-kappaB activation. CD30-mediated up-regulation of ICAM-1 expression led to a significant increase in cluster formation of lymph node cells. Increased lymphocyte self-aggregation mediated by CD30 may set the stage for fraternal signaling to modulate lymphocyte function.

ICAM-1 expression and the soluble ICAM-1 level for evaluating the metastatic potential of gastric cancer

ICAM-1 plays an important role in cell-cell and cell-extracellular matrix interactions, especially tumor invasion and cytotoxicity of lymphocytes. In the present study, the relationship between metastasis of gastric cancer and ICAM-1 expression by cancer cells or the serum level of s-ICAM-1 was (s-ICAM-1) was examined. ICAM-1 was detected by immunohistochemic staining in 49.0% of 108 patients with gastric cancer. The ICAM-1 expression rate was higher at a more advanced stage, based on lymph node metastasis, being 46.9% in node-negative and 56.1% in node-positive cases. In patients with liver metastasis, the rate was 90.9%, while it was 43.3% in patients without liver metastasis (p < 0.05). The serum s-ICAM-1 level was 262.1 ng/ml (median 205.5, range 176.0-271.0) in healthy subjects and 391.5 ng/ml (median 317.5, range 148.7-1,768.0) in gastric cancer patients (p < 0.001). The serum s-ICAM-1 level was significantly higher in patients with liver metastasis than in patients without liver metastasis (p < 0.0001). In addition, positive ICAM-1 expression cases had significantly higher s-ICAM-1 levels than negative ones, 408.9 +/- 188.4 and 308.1 +/- 88.1 ng/ml, respectively. These results suggested that ICAM-1 was overexpressed in cancer cells and released as s-ICAM-1, which would promote hematogenous metastasis by suppressing local anticancer immunity.

Flow cytometric analysis of infiltrating cells in the peripheral nerves in experimental allergic neuritis

Experimental autoimmune neuritis (EAN) is an animal model that shares clinical, pathological and electrophysiological features with the human disease Guillain-Barré syndrome (GBS). In this study, we isolated and characterized by fluorescent activated cell sorter (FACS) phenotype of the inflammatory cells infiltrating cauda equina (CE) of Lewis rats at the active stage of the disease. We found that at this stage of EAN macrophages (Mphi) and alphabeta T cells were two major populations isolated from CE. We also found that among total cell population isolated from CE, gammadelta T and NK cells composed two small but distinct populations, while B cells were negligible. We characterized phenotype of alphabeta T cells in CE as CD45RC(+)CD8(+) (activated cytotoxic lymphocytes) and CD45RC(-)CD4(+) (memory Th cells). The phenotype of gammadelta T cells was found to be consisted of only CD45RC(+)CD8(+) cells. Both alphabeta and gammadelta T cells in CE expressed a higher level of CD25, CD44 and CD54 activation markers compared to the other tissues. Immunohistochemistry demonstrated that gammadelta T cells existed apart from the intense cellular infiltrate. This is the first report on the isolation and FACS analysis of CE-infiltrating cells, contributing a new and alternative approach to study the inflammatory lesions in EAN. We conclude that both alphabeta and gammadelta T cells have a unique activation/inflammatory phenotype required to traffic through and be retained in the peripheral nerves during EAN.

Interferon-alpha activates cytotoxic function but inhibits interleukin-2-mediated proliferation and tumor necrosis factor-alpha secretion by immature human natural killer cells

Natural killer (NK) cells play an important role in host defense mechanisms against infection and neoplasia. Interferon-alpha (IFN-alpha) has been shown to activate NK cells and to augment their cytotoxic activity, albeit its role in the maturation pathway of NK cells has not been elucidated. The present study examined whether IFN-alpha activates the immature NK subset (Free cells) to become cytotoxic and also ascertained whether IFN-alpha uses the same pathway of activation as that mediated by interleukin-2 (IL-2). Incubation of sorted Free cells overnight with IFN-alpha resulted in augmentation of their cytotoxic function against NK sensitive target cells. The enhanced cytotoxic activity was not accompanied by a new recruitment of NK-target binder cells but by an increase in the frequency of killer cells in the conjugate fraction. Activation of the Free subset by IFN-alpha resulted in upregulation of CD69, CD11b, and CD2 surface expression and stimulated secretion of IFN-gamma. Unlike IL-2, IFN-alpha did not stimulate the Free cells to proliferate or secrete TNF-alpha and activation of cytotoxicity and modulation of surface antigens by IFN-alpha were independent of TNF-alpha. The failure of IFN-alpha to stimulate secretion and proliferation by Free cells appeared to be mediated by negative signals. This was corroborated in experiments demonstrating that when Free cells were cultured with both IFN-alpha and IL-2, a significant inhibition was observed for both the IL-2 dependent secretion of TNF-alpha and proliferation. These results demonstrate that IFN-alpha serves as both an activator and a regulator of NK function. Further, activation of the immature Free NK cells by IL-2 and IFN-alpha proceeds by TNF-alpha- dependent and independent pathways, respectively. The findings also support our contention that the mechanism of activation of the cytotoxic machinery of NK cells is not linked to the mechanism of activation of cytokine secretion and/or proliferation.

Immunohistochemical study of the distribution of intercellular adhesion molecule-1 and lymphocyte function-associated antigen-1 in chronic type B hepatitis

The expression of intercellular adhesion molecule-1 (ICAM-1) and lymphocyte function-associated antigen-1 (LFA-1) in the livers of 11 patients with chronic hepatitis B was studied immunohistochemically by light and electron microscopy to clarify the role of these adhesion molecules in tissue damage in chronic hepatitis B. On hepatocytes, ICAM-1 expression was confined to the bile canalicular surface when the liver inflammation was mild. In contrast, when the liver inflammation was severe, ICAM-1 was distributed on the entire surface of the hepatocyte, including the sinusoidal and lateral membranes; lymphocytes which were mostly positive for LFA-1, were often observed invading deeply among these hepatocytes. The degree of ICAM-1 expression on the hepatocytes was also related to the expression of HLA class 1 antigen. In liver showing diffuse expression of ICAM-1 on the hepatocytes, strong expression of HLA class 1 antigen was observed, and amounts of HBV in the liver were decreased. Diffuse expression of ICAM-1 and HLA class 1 antigen was mostly observed after acute exacerbation of liver inflammation. These results suggest that the ICAM-1/LFA-1 pathway is involved in the immunological mechanism responsible for liver cell damage in chronic hepatitis B.

Pentoxifylline suppresses interleukin-2-mediated activation of immature human natural killer cells by inhibiting endogenous tumor necrosis factor-alpha secretion

We recently reported that immature human peripheral blood-derived natural killer (NK) cells, the free NK subset, can be activated by interleukin-2 (IL-2) to become killer cells and to undergo proliferation. Activation by IL-2 is dependent on endogenous secretion of tumor necrosis factor-alpha (TNF-alpha) by the free cells. Because pentoxifylline (PTX) inhibits TNF-alpha synthesis and secretion in monocytes, we hypothesized that PTX may also inhibit TNF-alpha secretion by NK cells and thus would inhibit IL-2-mediated activation of free cells. The free NK cells were separated from purified NK cells by flow cytometry and cell sorting of non-target binding cells. IL-2-mediated secretion of TNF-alpha by the free cells was inhibited by PTX. In the presence of PTX, IL-2-mediated activation of free cells into cytotoxic function, proliferation, and recruitment of binder and killer cells was markedly inhibited. Also, PTX inhibited IL-2-triggered upregulation of the expression of CD69, CD25, ICAM-1, and p75TNF-R on the cell surface. These findings demonstrate that PTX has a marked suppression on IL-2-mediated activation of immature free NK cells and that the suppression is due, in large part, to PTX-mediated inhibition of endogenous TNF-alpha secretion. The implication of these findings in the clinical use of PTX for therapy is discussed.

Distribution of cell adhesion molecules in skeletal muscle from patients with systemic lupus erythematosus

OBJECTIVE

To investigate the pathophysiology of perivascular mononuclear cell infiltrates observed in skeletal muscle from patients with systemic lupus erythematosus (SLE).

METHODS

Immunocytochemical techniques were used to examine frozen 5 microns sections from the quadriceps needle muscle biopsy specimens of 14 patients with SLE (including seven with infiltrates) for the expression of the cytokine inducible adhesion molecules intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin.

RESULTS

Vessels in 6/7 SLE biopsy specimens with perivascular infiltrates expressed VCAM-1 at a density of > 2 vessels/mm2 in contrast with 0/7 SLE biopsy specimens without infiltrates and 1/6 control specimens. In contrast, E-selectin expression was increased ( > 0.3 positive vessels/mm2) in SLE biopsy specimens compared with control tissue regardless of the presence of perivascular infiltration. VCAM-1 and ICAM-1 were also noted on extravascular cells in the infiltrates, being particularly prominent on the intermuscle fibre dendritic processes of CD68+ HLA-DR+ cells.

CONCLUSION

Expression of these cytokine inducible adhesion molecules may be important in the migration of mononuclear cells into skeletal muscle and may be involved in intercellular interactions within the tissue.

Expression of adhesion molecules by bladder cancer cells: modulation by interferon-gamma and tumour necrosis factor-alpha

The constitutive expression by eight human bladder cancer cell lines of the cell adhesion molecules intercellular adhesion molecule-1 and intercellular adhesion molecule-2 was studied using monoclonal antibody probes in conjunction with flow-cytometry. Tumour lines of low grade (G1) did not constitutively express intercellular adhesion molecule-1, rather they were found to express intercellular adhesion molecule-2. The G2 cells expressed no intercellular adhesion molecule-2, however, a low percentage did express intercellular adhesion molecule-1. High grade cells (G3) only expressed intercellular adhesion molecule-1 on their cell surface but at higher levels than the G2 cell line. Exposure of the bladder cancer cell lines to interferon-gamma induced and augmented the expression of intercellular adhesion molecule-1 by all except one of the cell lines (UMUC3). Intercellular adhesion molecule-2 expression remained unaltered. The modulation of intercellular adhesion molecule-1 expression was dependent on the concentration of interferon-gamma and the duration of stimulus. De novo intercellular adhesion molecule-1 expression, induced by interferon-gamma, was rapid (< 4 hours) with only a short period of stimulation being required (< 10 seconds). The rapid increase in expression of intercellular adhesion molecule-1 required de novo protein synthesis and was not the result of release of intercellular adhesion molecule-1 from an intracellular pool. Interferon-gamma and tumour necrosis factor-alpha were found to act synergistically in the induction and augmentation of intercellular adhesion molecule-1 expression. Optimal induction occurred with 10 Uml-1 of both molecules. These results suggest a correlation between constitutive adhesion molecule expression and the histopathological grade of the tumour. The implications of these findings for Bacillus Calmette Guerin and interferon-gamma immunotherapy of bladder cancer is discussed.