Expression of adhesion molecules and costimulatory molecules in inflammatory myopathies

To clarify the local immune responses in inflammatory myopathies, we examine recent studies on expression of adhesion and costimulatory molecules. Adhesion molecules participate in MNC influx from blood vessels into muscle tissues and interactions of inflamed muscle cells with surrounded MNC. These antigens may work as costimulatory molecules in antigen presenting process by muscle cells, as well as in augmentation of inflammation by infiltrating MNCs.     

Cell adhesion molecules and cancer metastasis

The adhesive interaction between tumor cells and host cells or the extracellular matrix plays a crucial role in metastasis formation. Therefore, understanding the mechanism controlling metastasis may assist in the development of antimetastatic therapy. We have used synthetic or recombinant polypeptide analogues containing the Arg-Gly-Asp (RGD) sequence found in the functional domains of fibronectin, such as poly(RGD) or CH-271, to regulate the mechanisms involved in cell adhesion during the metastatic process. Poly(RGD) inhibited experimental lung and liver metastasis effectively when coinjected i.v. with various types of tumors. In a model of spontaneous lung metastasis using the B16-BL6 melanoma, repeated administration of this polypeptide before or after surgical excision of the primary tumor resulted in a significant inhibition of tumor metastasis without affecting the growth of the primary tumor and substantially prolonged the survival time of mice. The mechanism responsible for the inhibition of tumor metastasis by the polypeptides is at least partly associated with the ability to interfere with cellular functions such as adhesiveness, motility and invasiveness in the process of metastasis. Combined treatment of the CH-271 fusion polypeptide and anticancer drugs, i.e., anti-adhesion therapy combined with chemotherapy, caused a marked inhibition of lung and liver metastasis of tumors as compared with either treatment alone or with the control. In contrast, the promotion of tumor cell interaction with immune cells via cell adhesion molecules, which differs from the anti-adhesive mechanism, may lead to the induction of anti-tumor immune responses and, consequently, to the inhibition of tumor metastasis. The transfection of the gene of the B7-1 adhesion molecule into tumor cells (B16-BL6 or K1735-M2 melanoma) resulted in the remarkable reduction of lung metastasis caused by the i.v. injection into mice. Immunization of B7-transfected tumor was effective as a tumor vaccine for preventing the metastasis of B7 negative original tumor cells. Thus, the regulation of the adhesive interaction with tumor cells may provide a new and promising approach for the control and prevention of cancer metastasis.     

Endothelial expression of adhesion molecules

We have identified the three genes pssCDE in Rhizobium leguminosarum bv. trifolii TA1. Even though they were almost identical to earlier identified pssCDE genes of R. leguminosarum, they differed in gene lengths and gene overlaps. The predicted gene products of pssCDE genes shared significant homology to prokaryotic glycosyl transferases involved in exopolysaccharide synthesis. The Tn5 insertion in pssD created the nonmucoid mutant that induced non-nitrogen-fixing nodules. The microscopic analysis of the nodules, induced on Trifolium pratense by the pssD133 mutant, showed abnormally enlarged infection threads densely packed with bacteria, which were released from the infection threads in an unusual way. The symbiosomes were observed very rarely and the nodule remained almost empty. Symbiotic phenotype of the pssD133 suggested a correlation between this mutation and defective endocytosis of bacteria into nodule cells.     

Differential expression of costimulatory molecules in chronic inflammatory periodontal disease tissue

OBJECTIVES: To present the technique of the extended subcranial approach to the anterior skull base and to review the results in 55 patients who underwent the procedure. STUDY DESIGN: Retrospective review of the records of 55 patients who underwent the extended subcranial approach to the anterior skull base between 1994 and 1998 for the treatment of various neoplasms originating in the nasal cavity, nasopharynx, paranasal sinuses, orbit, or meninges, as well as for the repair of complex craniofacial trauma and/or cerebrospinal fluid (CSF) leak. Preoperative patient evaluation and the surgical technique are also reviewed. METHODS: Patient records were retrospectively reviewed and tabulated for age, sex, and indications for procedure, with special focus on early outcome and complications. RESULTS: Twenty-six patients underwent oncologic resections, 22 patients had reduction of complex fronto-naso-orbital and skull base fractures, and seven patients had repair of CSF leak. Significant complications in the oncologic group consisted of one hematoma requiring needle aspiration and two cases of temporary nontension pneumocephalus. In the fracture group, one patient died because of extensive intracerebral damage and multiorgan failure, and one patient had nontension pneumocephalus coupled with CSF leakage and one patient had temporary nontension pneumocephalus. The most common late complication in all three groups was anosmia. CONCLUSIONS: Based on their review, the authors conclude that the extended subcranial approach to the anterior skull base is a safe, versatile, and effective procedure for the surgical treatment of various pathological conditions involving the anterior skull base.     

The expression of T cell related costimulatory molecules in multiple myeloma

Presentation of tumour antigen by malignant cells not expressing costimulatory molecules is considered to be a major cause of the failure of the host's immune response against tumours. This study has determined the expression of the B7 family of costimulatory molecules on malignant plasma cells and the expression of the counter receptor molecules, CD28 and CD152 (CTLA-4), on T cells of patients with multiple myeloma. CD28 expression was present on most CD4 cells but was lower on CD8 cells especially from those patients who also showed evidence of expanded T cell clones (median 40%. z=2.4; p<0.02). CD152 expression was increased in 50% (9/18) of patients with myeloma. CD80 (B7-1) expression was present on the plasma cells of only 1 of 27 samples but CD86 (B7-2) expression within the normal range was present on the plasma cells of 14 of 27 samples. Primitive plasma cells (CD38++ CD45++) had a higher expression of CD86 (median 78%) than mature plasma cells (CD38++ CD45-) (median 19%, z=3.7; p<0.01). Thus patients with expanded T cell clones have a downregulated T cell CD28 expression and lack B7-1 expression on their malignant plasma cells. These results are consistent with the concept that engagement of the T cell receptor by tumour antigen on B7-1 deficient malignant plasma cells would result in T cell anergy rather than productive immunity.     

Effects of preservation techniques on in vivo expression of adhesion molecules by aortic valve allografts

Methods of sterilization and preservation of aortic valve allografts influence graft longevity. The effect of storage techniques on valve durability may be mediated by alterations in the immunologic properties of the allograft, which are reflected by expression of leukocyte adhesion molecules. Rat aortic valve grafts were transplanted in the fresh state, after cryopreservation (-196 degrees C), or after storage at 4 degrees C for 1 to 21 days. Syngeneic and strongly allogeneic valves were transplanted for 4 hours to 21 days and were retrieved for immunohistochemical staining for expression of leukocyte adhesion molecules. Unimplanted valves and transplanted syngeneic valves, regardless of storage methods, exhibited little or no expression of leukocyte adhesion molecules. Fresh allogeneic valves expressed all molecules, indicating up-regulation, at all time intervals studied. Cryopreserved allogeneic valves demonstrated no leukocyte adhesion molecules at 4 hours or 2 days and weak reactivity at 10 and 21 days. Allogeneic valves stored at 4 degrees C, regardless of the duration of storage, demonstrated weak expression of all molecules at 10 days and strong expression at 21 days. Expression of leukocyte adhesion molecules requires an allogeneic environment and may precede immune-mediated injury. Reduced expression of leukocyte adhesion molecules resulting from storage may predict a diminished immunologic response. Cryopreservation (-196 degrees C) causes the greatest delay and diminution of expression of leukocyte adhesion molecules.     

Specific pattern of circulating endothelial adhesion molecules in HIV-associated Kaposi''s sarcoma

BACKGROUND: Micrometastases within bone marrow have been shown to indicate a poor prognosis in patients with epithelial tumours. However, the degree to which micrometastases represent true residual disease or cell shedding and metastatic potential, is unclear. AIM: To explore whether micrometastases represent residual disease, bone marrow taken from carefully staged patients before and after (> 6 months) "curative" resection of a primary gastrointestinal cancer was studied prospectively. PATIENTS/METHODS: Seventy two consecutive patients were studied; the only exclusions were patients with known overt metastatic disease at the time of surgery. Micrometastatic cells were quantified per 10(5) marrow cells by flow cytometry after staining for contaminant cytokeratin-18 positive cells. RESULTS: Micrometastases were detected preoperatively in 22% (16/72) of all patients, comprising 11 (23%) of 48 with colorectal cancer, five (33%) of 15 with gastric adenocarcinoma and none (0%) of nine with oesophageal squamous cancer. Although fewer metastatic cells were detected in postoperative bone marrow, and clearance of marrow deposits was evident in most patients, the persistence of micrometastases in five of 16 patients after resection, without evidence of tumour recurrence, indicates a subset with true residual disease. Detection of micrometastases postoperatively (persistent or newly developed) was significantly associated with development of overt metastases during the subsequent 12-18 months of follow up (nine of 19 patients) when compared with patients testing negative for micrometastases (eight of 53; p < 0.01). CONCLUSIONS: Preoperative detection of micrometastases may reflect either transient shedding of cells, metastatic potential or residual disease, but postoperative micrometastases indicate minimal residual disease. Identification of these patients is important because they may benefit from adjuvant therapy.     

Differential expression and distribution of focal adhesion and cell adhesion molecules in rat hepatocyte differentiation

The present study has examined the distribution of axons of differing sizes in the optic pathway of the ground squirrel. Axon diameters were measured from electron micrographs at various locations across sections of the optic nerve and tract, and total distributions and numbers were estimated. In both the nerve and tract, roughly 1.2 million optic axons were present. The population of optic axons had a unimodal size distribution, peaking at 0.9 microm in diameter and having an extended tail toward larger diameters. Local axon diameter distributions in the optic tract indicated distinct (though partially overlapping) axon diameter classes, including one of fine sizes peaking at 0.8-0.9 microm, a second of medium sizes peaking around 1.7-1.8 microm, and a third composed of the larger fibers with diameters up to 4.8 microm. The fine-caliber axons were found at all locations in the tract, and were the only axons present immediately adjacent to the pia, while the medium- and coarse-caliber axons were found at deeper locations. Curiously, the larger axons were found primarily in the medial parts of the tract, where axons from the dorsal retina normally course. A similarly restricted distribution of the larger axons was observed in the dorsotemporal parts of the optic nerve, suggesting that this difference in the tract may relate to an asymmetric distribution of ganglion cells on the retina giving rise to these axons. Measurements of axonal size taken within the optic fiber layer in dorsal and ventral parts of the retina confirmed this asymmetry, consistent with previous demonstrations of soma size differences in the dorsal versus ventral retina. The partial segregation of axons by size in the optic tract of the ground squirrel then reflects both the asymmetric distribution of retinal ganglion cell classes and the chronotopic reordering of optic axons that occurs within the chiasmatic region.     

Increased expression of costimulatory molecules on peripheral blood monocytes in patients with Crohn's disease

BACKGROUND: Activation of T lymphocytes and monocytes/macrophages has been implicated in the pathogenesis of Crohn's disease (CD). Costimulatory molecules play important roles in optimal T-cell activation. METHODS: With flow cytometric analysis we have investigated the expression of the costimulatory molecules B7-1 (CD80), B7-2 (CD86), and CD18 and the intercellular adhesion molecule-1 (ICAM-1) on peripheral blood monocytes and the expression of the activation markers HLA-DR and IL-2R (CD25) on peripheral blood T lymphocytes from 31 CD patients, 17 ulcerative colitis (UC) patients, and 10 healthy controls. RESULTS: In CD patients the percentage of activated T cells (CD3+ HLA-DR+ and CD3+ IL-2R+) was significantly increased compared with those of controls and UC patients (P < 0.05). Most monocytes from all three groups expressed B7-2, CD18, and ICAM-1 molecules (all > 79%), but only a few positive cells expressed B7-1 molecules (< 5%). No significant differences were detected in the percentage positivity of all costimulatory molecules tested among CD, UC, and controls. The mean fluorescence intensity (MFI) of B7-1 in all three groups was very weak and not significantly different. However, in CD patients there was a significantly increased MFI of B7-2, CD18, and ICAM-1 molecules compared with UC and controls (P < 0.05). On the other hand, both the percentage positivity and MFI of HLA-DR molecules on monocytes of UC patients were significantly lower than those of CD patients and controls (P < 0.05). CONCLUSIONS: Expression of the costimulatory molecules B7-2, CD18, and ICAM-1 on peripheral blood monocytes of CD patients is increased. In CD patients activation of peripheral T lymphocytes may correlate with increased expression of these costimulatory molecules on peripheral blood monocytes.     

Lymphocyte subsets and adhesion molecules expression in heatstroke and heat stress

Adaptation of the cerebral circulation to microgravity was investigated in rat middle cerebral arteries after 20 days of hindlimb unweighting (HU). Myogenic responses were measured in isolated, pressurized arteries from HU and control animals. Maximal passive lumen diameters, obtained in the absence of extracellular Ca2+ plus EDTA, were not significantly different between groups (249 vs. 258 micrometer). In physiological salt solution, arteries from both HU and control animals maintained a constant lumen diameter when subjected to incremental increases in transmural pressure (20-80 mmHg). However, the diameter of arteries from HU animals was significantly smaller than that of arteries from control animals at all pressures; this difference could be eliminated by exposure to the nitric oxide synthase inhibitor NG-nitro-L-arginine methyl ester. After HU treatment, transient distensibility of the artery wall in response to pressure was also significantly decreased, whereas the frequency and amplitude of vasomotion were increased. The latter changes were not affected by NG-nitro-L-arginine methyl ester. Thus simulated microgravity increases cerebral artery myogenic tone through both nitric oxide synthase-dependent and -independent mechanisms.     

Leukocyte adhesion molecules in the liver and plasma cytokine levels in endotoxin-induced rat liver injury

BACKGROUND: The interactions between polymorphonuclear neutrophils (PMNs) and sinusoidal endothelial cells (SECs) have been known to be involved in the pathogenesis of acute liver injury. It has been also reported that tumor necrosis factor-alpha (TNF-alpha) up-regulates ICAM-1 expression on SECs and that interleukin-8 (IL-8) provokes rapid activation of CD11/CD18 on PMNs. These findings expand into the relationship between the expression of leukocyte adhesion molecules (ICAM-1, CD11a/CD18 and CD11b/CD18) in liver tissues and plasma TNF and IL-8 levels after lipopolysaccharide (LPS)-induced liver injury in rats. METHODS: Male Wistar rats weighing 200-250 g were treated with 2 mg LPS/kg intravenously in a 0.2- to 0.25-ml volume. Liver and blood samples were obtained at 1, 3, 8, and 12 h after LPS exposure. Plasma TNF and IL-8 levels were measured using bioassay and specific enzyme-linked immunosorbent assay, respectively. Liver samples were fixed and studied by immunohistochemistry using specific monoclonal antibodies against ICAM-1, CD11a, and CD11b. RESULTS: The TNF level showed a peak at 1 h (23.3 +/- 11.4 IU/ml), and the IL-8 level showed a peak at 3 h (343.1 +/- 110.5 ng/ml) after LPS exposure. An increase in the number of PMNs in the liver was observed as early as 1 h and continued until 12 h after LPS exposure. PMNs adhered to degenerated SECs and hepatocytes. ICAM-1 on SECs was diffusely and strongly expressed at 8 h, and PMNs adhered to SECs expressed both CD11a and CD11b. ICAM-1 was also observed on hepatocytes. CONCLUSION: These data suggest that PMN-SEC and PMN-hepatocyte interactions via leukocyte adhesion molecules, related to inflammatory cytokines such as TNF and IL-8, exist and play an important role in the pathogenesis of acute liver injury.     

Fibrolamellar carcinoma of the liver: composition of the extracellular matrix and expression of cell-matrix and cell-cell adhesion molecules

We have analyzed the composition of the tumor stroma and the expression of cell-matrix and cell-cell adhesion molecules in 11 cases of fibrolamellar carcinoma of the liver (FLC), in comparison with 34 cases of hepatocellular carcinoma and 8 cases of focal nodular hyperplasia. Fibrolamellar carcinoma was characterized by the presence of large amounts of tenascin in tumor stroma and by the scarce expression of basement membrane components at the contact of neoplastic clusters. Like normal hepatocytes, neoplastic cells constantly expressed the alpha1 integrin chain, lacked the beta4 integrin chain, and coexpressed E-cadherin and the hepatocyte N-related cadherin. Abnormalities in the expression of cell adhesion molecules, including altered cadherin expression, alphaV integrin chain induction, and CD44 expression, were detected in the majority of cases. The composition of the tumor stroma and the pattern of expression of cell adhesion molecules in fibrolamellar carcinoma were reminiscent of those observed in grade III and grade IV hepatocellular carcinomas. Our results therefore show that, despite its slow local growth and good prognosis, fibrolamellar carcinoma expresses many characteristics usually associated with clinically aggressive malignancies. Further studies are needed to identify the factors responsible for the apparent dissociation between clinical behavior and biological characteristics in this tumor.     

Comparison of the pattern of integrin expression between primary tumors and liver metastasis of gastric and colorectal cancers

To investigate the interrelationship between integrin VLA3 overexpression and liver metastasis, immunohistochemical studies of VLA3 were made in 73 cases of gastric cancer (66 cases without liver metastasis, 7 cases with liver metastasis) and 15 cases of colorectal cancer (3 cases without liver metastasis, 12 cases with liver metastasis). The rate of integrin VLA3 expression in 69 primary gastric and colorectal cancers without liver metastasis was 41%, that was higher than that (0%) in the 19 primary tumors of gastric and colorectal cancers with liver metastasis. In contrast, the positive rate for integrin VLA3 staining in 19 cases involving liver metastasis of gastric and colorectal cancers was 58% (11/19), which was higher than that (0%) in primary tumors. These findings suggest that VLA3 may play an important role in the process of liver metastasis of gastric and colorectal cancers.     

Effects of liposome-encapsulated hemoglobin on phorbol ester-induced superoxide production and expression of costimulatory molecules by monocytes in vitro

The effects of Neo Red Cell (NRC), a liposome-encapsulated hemoglobin (LEH), on the phorbol ester-induced superoxide production and the expression of costimulatory molecules by human peripheral monocytes were investigated. The treatment of human mononuclear cells with NRC caused the potentiation of superoxide production in response to PMA. The longer incubation (20 h) resulted in a decrease in the PMA-induced superoxide production, which was in parallel to a decrease in the viability of the monocytes. A flow cytometric analysis showed that a slight expression of CD80 (B7-1) on monocytes was induced by NRC treatment, whereas the constitutive expressions of CD86 (B7-2) and CD54 (ICAM-1) were unchanged. The activation of monocytes with interferon-gamma (IFN-gamma) induced the expressions of CD80, CD86, and CD54 under all conditions tested, but NRC treatment tended to decrease the IFN-gamma-induced expression of CD54 on monocytes. These results suggest that the administration of LEH may modify the functions of human monocytes.     

Inhibition of adhesion molecules markedly ameliorates cytokine-induced sustained myocardial dysfunction in dogs in vivo

Adhesion molecules are key molecules for inflammatory cardiovascular diseases and are known to be up-regulated by inflammatory cytokines. However, the role of adhesion molecules in the cytokine-induced myocardial dysfunction in vivo remains unclear. This role was examined in our novel canine model, in which chronic treatment of the heart with IL-1 beta-bound microspheres (MS), but not control MS, causes sustained myocardial dysfunction in vivo. The expression of P-selectin (mRNA and immunoreactivity) was more prominent in the IL-1 beta group than in the control group (treated with control MS alone) after MS injection. The extent of neutrophil infiltration and myocardial myeloperoxidase (MPO) activity were significantly increased in the IL-1 beta group (P < 0.01). Pre-treatment with SLeX-OS (a novel oligosaccharide analog of sialyl LewisX) or PB1.3 (a monoclonal antibody to P-selectin) prevented the myocardial dysfunction and significantly suppressed the neutrophil infiltration and the increase in myocardial MPO activity induced by IL-1 beta (P < 0.01 each). These results indicate that adhesion molecules play an important role in the pathogenesis of the cytokine-induced sustained myocardial dysfunction in dogs in vivo.