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Chemotactic chemokines can be released from lung fibroblasts in response to interleukin (IL)-1[beta] and tumor necrosis factor (TNF)-[alpha]. An imbalance between proteases and anti-proteases has been observed at inflammatory sites, and, therefore, protease inhibitors might modulate fibroblast release of chemotactic cytokines. To test this hypothesis, serine protease inhibitors (FK-706, [[alpha].sub.1]-antitrypsin, or N[alpha]-p-tosyl-L-lysine chloromethyl ketone) were evaluated for their capacity to attenuate the release of neutrophil chemotactic activity (NCA) or monocyte chemotactic activity (MCA) from human fetal lung fibroblasts (HFL-1). Similarly, the release of the chemoattractants IL-8, granulocyte colony-stimulating factor, monocyte chemoattractant protein-1, macrophage colony-stimulating factor, and granulocyte/macrophage colony-stimulating factor, from HFL-1, were evaluated in response to IL-1[beta] and TNF-[alpha]. NCA, MCA, and chemotactic cytokines were attenuated by FK-706. However, matrix metalloproteinase inhibitors were without effect, and cysteine protease inhibitors only slightly attenuated chemotactic or cytokine release. These data suggest that IL-1[beta] and TNF-[alpha] may stimulate lung fibroblasts to release NCA and MCA by a proteasedependent mechanism and that serine protease inhibitors may attenuate the release. neutrophil; monocyte; interleukin-8; monocyte chemoattractant protein-1; granulocyte/macrophage colony-stimulating factor

The potential of the A549 type II epithelial cell line to release granulocyte colony-stimulating factor (G-CSF) as neutrophil chemotactic activity (NCA) was evaluated. It was demonstrated that A549 cells released G-CSF as NCA in response to interleukin-1 beta, tumor necrosis factor-alpha, lipopolysaccharide and bradykinin. The expression of G-CSF mRNA was augmented in response to each stimulus. These suggested that alveolar type II cells may produce G-CSF as NCA and may participate in the regulation of neutrophil extravasation into the lung.

Experiments were performed to investigate the capacity of the human lung fibroblast (HLF) to induce monocyte chemokinetic activity (MCA) through the release of the transforming growth factor-beta, leukotriene B4 (LTB4) and the granulocyte-macrophage colony-stimulating factor. The attenuation of the MCA and its lowest molecular weight peak was attributed to an LTB4-receptor antagonist. These findings emphasize the role of HLFs as modulators of monocyte recruitment in the lungs.

A study was conducted to investigate the influence of acetylcholine (ACh) on alveolar macrophages (AM) in releasing inflammatory cell chemotactic activities. A Ficoll-Hypaque density centrifugation was utilized to separate red blood cells and neutrophils from mononuclear cells. Results showed that ACh plays a critical role in inflammatory cell recruitment and stimulates the release of lipoxygenase-based chemotactic activities.

The role of type II pneumocytes in the maintenance of host defense and alveolar immune environment was analyzed in A549 cell lines. Analysis of A549 cell supernatant fluids indicated the ability of type II pneumocytes to generate chemotactic factors that promote chemoattractant activity for monocytes in a time-dependent manner. Furthermore, the A549 supernatant contained transforming growth factor-beta, monocyte chemoattractant protein-1 and leukotriene B4.

The release of neutrophil and monocyte chemotactic activity (NCA and MCA) by bronchial epithelial cells may be stimulated by bradykinin (BK) and histamine. Histamine and BK may assist monocyte and neutrophil airway activity in asthmatics. In a study of cultured cow lung epithelial cells, BK had strongly stimulating effect, histamine had a weaker effect, and serotonin had no effect at all. Checkerboard analysis revealed a chemotactic response is shown by NCA and MCA to BK.

Cyclophosphamide is an alkylating antineoplastic agent used in several conditions. However, little is known about the mechanism of its pulmonary toxicity. In the present study, we determined that human lung fibroblasts release activity for neutrophils and monocytes in response to cyclophosphamide in a dose- and time-dependent manner. Checkerboard analysis revealed that both neutrophil and monocyte activities were chemotactic. The release of chemotactic activity was inhibited by lipoxygenase inhibitors and cycloheximide. Molecular-sieve column chromatography revealed that both neutrophil (NCA) and monocyte (MCA) chemotactic activities had multiple peaks. NCA was inhibited by a leukotriene [B.sub.4] receptor antagonist and anti-interleukin-8 and anti-granulocyte colony-stimulating factor antibodies. MCA was attenuated by a leukotriene [B.sub.4] receptor antagonist and anti-monocyte chemoattractant protein-1 and anti-granulocyte-macrophage colony-stimulating factor antibodies. The concentrations of interleukin-8, granulocyte colony-stimulating factor, monocyte chemoattractant protein-1, and granulocyte-macrophage colony-stimulating factor significantly increased in response to cyclophosphamide. These data suggest that lung fibroblasts may modulate inflammatory cell recruitment into the lung by releasing NCA and MCA in response to cyclophosphamide. interstitial lung disease; interleukin-8; granulocyte colony-stimulating factor; monocyte chemoattractant protein-1; granulocyte-macrophage colony-stimulating factor

Koyama, Sekiya, Etsuro Sato, Hiroshi Nomura, Keishi Kubo, Masakazu Miura, Tetsuji Yamashita, Sonoko Nagai, and Takateru Izumi. The potential of various lipopolysaccharides to release IL-8 and G-CSF. Am J Physiol Lung Cell Mol Physiol 278: L-658-L666, 2000.--Lipopolysaccharide (LPS) derived from Pseudomonas aeruginosa is less cytotoxic than that from Escherichia coli. But P. aeruginosa induces a prominent sustained lung inflammation as in cystic fibrosis and diffuse panbronchiolotis. The present study examined the potential for several LPSs obtained from E. coli and P. aeruginosa to release neutrophil chemotactic activity (NCA) from lung cells. LPSs differently stimulated A549 cells, BEAS-2B cells, and lung fibroblasts to release NCA [P. aeruginosa [is greater than] E. coli 0127:B8 (Difco) [is greater than] E. coli 055:B5 (Sigma) [is greater than] E. coli 026:B6 (Sigma)]. E. coli 0127;B8 (Sigma) and 0111:B4 (Sigma) did not stimulate these cells. NCA was chemotactic by checkerboard analysis. Molecular-sieve column chromatography revealed three chemotactic peaks. The release of NCA was inhibited by cycloheximide and lipoxygenase inhibitors. Experiments with blocking antibodies suggested that much of the NCA was secondary to the release of interleukin (IL)-8 and granulocyte colony-stimulating factor (G-CSF). Thus we examined the concentrations of IL-8 and G-CSF and found that the potency of the various LPSs to stimulate NCA closely paralleled the potency in releasing A549 cells was observed. Finally, the release of IL-6 showed similar results. These data suggest that P. aeruginosa LPS may stimulate lung cells to release more NCA than E. coli LPSs, leading to sustained lung inflammation. Pseudomonas aeruginosa; interleukin-8; granulocyte colony-stimulating factor; interleukin-6; A549 cells; BEAS-2B cells; fibroblasts.

Sato, Etsuro, Sekiya Koyama, Akemi Takamizawa, Takeshi Masubuchi, Keishi Kubo, Richard A. Robbins, Sonoko Nagai, and Takateru Izumi. Smoke extract stimulates lung fibroblasts to release neutrophil and monocyte chemotactic activities. Am. J. Physiol. 277 (Lung Cell. Mol. Physiol. 21): L1149-L1157, 1999.--Accumulation of monocytes and neutrophils and fibrous distortion of the airway are characteristics of airway disease secondary to smoking. The presence of inflammatory cells and fibrosis correlate, and, therefore, we postulated that lung fibroblasts might release chemotactic activity for neutrophils and monocytes in response to smoke extract. To test this hypothesis, human fetal lung (HFL1) fibroblasts were cultured, and the supernatant fluid was evaluated for neutrophil (NCA) and monocyte (MCA) chemotactic activities with a blind well chamber technique. HFL1 fibroblasts released chemotactic activity in response to smoke extract in a dose- and time-dependent manner (P [is less than] 0.05). Checkerboard analysis showed that the activity was predominantly chemotactic. Partial characterization of the released chemotactic activity revealed that the activity was partly heat labile, trypsin sensitive, and ethyl acetate extractable. Lipoxygenase inhibitors and cycloheximide inhibited the release of both NCA and MCA. Molecular-sieve chromatography revealed that NCA and MCA were heterogeneous. NCA was inhibited by anti-human interleukin (IL)-8 and anti-granulocyte colony-stimulating factor antibodies and a leukotriene (LT) [B.sub.4]-receptor antagonist. Anti-granulocyte-macrophage colony-stimulating factor (GM-CSF) and anti-monocyte chemoattractant protein (MCP)-1 antibodies and an [LTB.sub.4]-receptor antagonist inhibited MCA. Immunoreactive IL-8, granulocyte colony-stimulating factor, GM-CSF, and MCP-1 significantly increased in culture supernatant fluid in response to smoke extract. Finally, smoke extract augmented the expression of mRNAs of IL-8, GM-CSF, and MCP-1. These data demonstrate that lung fibroblasts release NCA and MCA in response to smoke extract and suggest that lung fibroblasts may modulate the inflammatory cell recruitment into the lung. interleukin-8; granulocyte colony-stimulating factor; monocyte chemoattractant protein-1; granulocyte-macrophage colony-stimulating factor; fibrosis; chemotaxis; smoking

Sato, Etsuro, Keith L. Simpson, Matthew B. Grisham, Sekiya Koyama, and Richard A. Robbins. Effects of reactive oxygen and nitrogen metabolites on MCP-1-induced monocyte chemotactic activity in vitro. Am. J. Physiol. 277 (Lung Cell. Mol. Physiol. 21): L543-L549, 1999.--Peroxynitrite, an oxidant generated by the interaction between superoxide and nitric oxide (NO), can nitrate tyrosine residues, resulting in compromised protein function. Monocyte chemoattractant protein-1 (MCP-1) is a chemokine that attracts, monocytes and has a tyrosine residue critical for function. We hypothesized that peroxynitrite would alter MCP-1 activity. Peroxynitrite attenuated MCP-1-induced monocyte chemotactic activity (MCA) in a dose-dependent manner (P [is less than] 0.05) but did not attenuate leukotriene [B.sub.4] or complement-activated serum MCA. The reducing agents dithionite, deferoxamine, and dithiothreitol reversed the MCA inhibition by peroxynitrite, and exogenous L-tyrosine abrogated the inhibition by peroxynitrite. PAPA-NONOate, an NO donor, or superoxide generated by xanthine and xanthine oxidase did not show an inhibitory effect on MCA induced by MCP-1. The peroxynitrite generator 3-morpholinosydnonimine caused a concentration-dependent inhibition of MCA by MCP-1. Peroxynitrite reduced MCP-1 binding to monocytes and resulted in nitrotyrosine formation. These findings are consistent with nitration of tyrosine by peroxynitrite, with subsequent inhibition of MCP-1 binding to monocytes, and suggest that peroxynitrite may play a role in regulation of MCP-1-induced monocyte chemotaxis. nitric oxide; monocyte migration; superoxide; nitrotyrosine; monocyte chemoattractant protein-1

A study has been conducted to investigate the side effects of the use bleomycin on cancer patients. To determine these effects, tests were done on harvested A549 cell supernatant fluid were evaluated for neutrophil and monocyte chemotactic activities. Findings have confirmed that bleomycin stimulates type II epithelial cells to release chemotactic activities and promote cell inflammation in the lungs, which could develop into diffuse interstitial lung fibrosis.

Methotrexate-induced pneumonitis has been reported as an infrequent but potentially serious complication of therapy in a variety of malignant and benign conditions. Because inflammatory cell infiltration is concerned with the development of methotrexate-induced pneumoinitis, and because airway epithelial cells participate in the orchestration of lung inflammation, the authors determined whether methotrexate might stimulate airway epithelial cells (A549 cells) to release neutrophil, monocyte, and eosinophil chemotactic activities (NCA, MCA, and ECA). A549 cells released NCA, MCA, and ECA in a dose- and time-dependent manner in response to methotrexate. Partial characterization revealed the heterogeneity of NCA, MCA, and ECA. The release of chemo-tactic activity was blocked by lipoxygenase inhibitors and cycloheximide. NCA was inhibited by leukotriene (LT) B[SUB4] receptor antagonist, and anti-interleukin (IL)-8 and granulocyte colony-stimulating factor (G-CSF) antibodies. MCA was attenuated by LTB[SUB4] receptor antagonist, and anti-monocyte chemoattractant protein (MCP)-1 and granulocyte-macrophage CSF (GM-CSF) (antibodies. ECA was attenuated by LTB[SUB4] receptor antagonist, and anti-IL-8 and GM-CSF antibodies. The release of IL-8, G-CSF, MCP-1, GM-CSF, and LTB[SUB4] from A549 cells significantly increased in response to methotrexate. The mRNA expression of IL-8 and MCP-1 was augmented by methotrexate stimulation. These data suggest that type II epithelial cells may modulate inflammatory cell recruitment into the lung by releasing NCA, MCA, and ECA in response to methotrexate. [ABSTRACT FROM AUTHOR]

Histamine and serotonin are important inflammatory mediators in the pathophysiology of asthma, and asthmatic patients have higher plasma histamine and serotonin levels than nonasthmatic control subjects. Eotaxin, a potent eosinophil-specific chemotactic factor, is increased in the lower respiratory tract of allergic patients. Recently, lung fibroblasts have been reported to produce eotaxin and are suggested to be the major cellular source of eotaxin. We postulated that lung fibroblasts might release eotaxin in response to histamine or serotonin. To test this hypothesis, we evaluated the potential of histamine or serotonin to induce the release of eotaxin by the human fetal lung fibroblast cell line, HFL-1. HFL-1 released eotaxin in response to histamine and serotonin in a dose- and time-dependent manner (p < 0.05). Histamine or serotonin treatment of HFL-1 augmented the expression of eotaxin mRNA. Eosinophil chemotactic activity by HFL-1 supernatant fluids was inhibited by anti-human eotaxin-neutralizing antibody. These findings lead to the hypothesis that lung-fibroblast-derived eotaxin may in part be responsible for the eosinophil infiltration observed in allergic disease of the airways.Copyright © 2002 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Growing evidence obtained from human genomic analysis and antigen-challenged transgenic mice suggests that interleukin-9 (IL-9) is a candidate factor in immunoglobulin E (IgE) production and thus is thought to be associated with bronchial inflammation and bronchial hyperresponsiveness (BHR). To evaluate the expression of the IL-9 receptor and its effect on the IL-9 human bronchial cell line BEAS-2B cells, reverse transcriptase-polymerase chain reaction (RT-PCR), immunohistochemical investigation, and chemotaxis assay were performed. The components of the IL-9 receptor, consisting of IL-9 receptor α (CD129) and IL-2 receptor γ (CD132), were expressed on BEAS-2B cells as determined by RT-PCR and flow cytometry. BEAS-2B cells exposed to IL-9 released neutrophil chemotactic activity (NCA) in a time- and dose-dependent manner, and the presence of granulocyte colony-stimulating factor (G-CSF) was also detected. This factor is primarily involved in NCA for the measurement of cytokines and in the inhibition assay of neutrophil chemotaxis. These findings suggest that bronchial epithelial cells may express IL-9 receptors, and that IL-9 may induce airway inflammation through the release of G-CSF from bronchial epithelial cells. [ABSTRACT FROM AUTHOR]

Background: Increasing evidence regarding asthma suggests that CD4+ cells are preferentially recruited to sites of bronchial inflammation. Interleukin (IL)-16 has been reported as playing an important role in the accumulation of CD4+ cells. We have shown that the CD4 molecule is expressed on normal human eosinophils by tumor necrosis factor (TNF)-α stimulation. Methods: We evaluated the effects of theophylline, KF19514 [a selective phosphodiesterase (PDE) IV inhibitor] and dexamethasone on CD4 expression on eosinophils and eosinophil migration in response to IL-16, a natural soluble ligand of the CD4 molecule. Results: The maximum eosinophil migration was observed when eosinophils were cultured with TNF-α at 10 ng/ml for 18 h and the concentration of IL-16 was 10 pg/ml. CD4+ eosinophil migration in response to IL-16 was mostly, if not fully, chemokinetic and this migration was significantly inhibited by Fab of anti-CD4 monoclonal antibody. Theophylline (10[sup –4] –10[sup –3] M), KF19514 (10[sup –7] –10[sup –6] M) and dexamethasone (10[sup –8] – 10[sup –6] M) significantly inhibited CD4 expression on eosinophils induced by TNF-α. Theophylline (10[sup –3] M) and KF19514 (10[sup –6] M) inhibited CD4+ eosinophil migratory responses induced by IL-16, but 10[sup –6] M dexamethasone did not. Theophylline and KF19514 augmented the intracellular adenosine-3′,5′-cyclic monophosphate (cAMP) concentration in eosinophils, suggesting modulation by cAMP of CD4 expression and eosinophil migration. Conclusions: These data suggest that TNF-α-induced CD4+ eosinophils may contribute to eosinophil migratory responses induced by IL-16. Theophylline and selective PDE IV inhibitor may prevent airway inflammation by downregulating CD4 expression on eosinophils and inhibiting eosinophil migration through CD4 and IL-16 interaction.Copyright © 2001 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Eotaxin, a potent eosinophil-specific chemotactic factor, is increased in the lower respiratory tract of asthma patients. Recently, lung fibroblasts have been reported to produce eotaxin and their activation can be modulated by inflammatory cytokines. To test the hypothesis that inflammatory cytokines modulate the eotaxin release from lung fibroblasts, we investigated the potential of interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), or interferon-γ (IFN-γ) to induce the release of eotaxin and eotaxin mRNA by the human fetal lung fibroblast cell line, HFL-1, was evaluated. HFL-1 released eotaxin constitutively without stimulation, but IL-1β or TNF-α stimulated eotaxin release in a dose- and time-dependent manner. IL-1β or TNF-α treatment of HFL-1 also resulted in the augmented expression of eotaxin mRNA. Although IFN-γ alone had negligible effect on eotaxin release and mRNA expression, IFN-γ induced a significant, concentration-dependent attenuation of eotaxin release and eotaxin mRNA expression from HFL1 stimulated with IL-1β or TNF-α . These findings are consistent with the concept that lung fibroblast-derived eotaxin may in part be responsible for the eosinophil infiltration observed in the airways ofasthmatic patients and that network ofcytokines may modulate the eosinophil recruitment to the airways by stimulation of fibroblasts to release eotaxin. [ABSTRACT FROM AUTHOR]

We reviewed the biological functions of CD4+ eosinophils, which are observed in peripheral blood, sputum and bronchoalveolar lavage fluid of various diseases. We have shown that CD4 molecules on human eosinophils are induced by tumor necrosis factor-alpha (TNF-α) stimulation. Interleukin-16 (IL-16) has been reported to bind a natural soluble ligand for the CD4 molecule. We reported that TNF-α-stimulated eosinophils migrate in a time- and dose-dependent manner against IL-16. Theophylline and dexamethasone significantly inhibited CD4 expression. Theophylline inhibited CD4+ eosinophil chemotaxis, but dexamethasone did not. Theophylline may prevent airway inflammation by downregulating the expression of CD4 molecule and CD4+ eosinophil migration. However, dexamethasone may inhibit airway inflammation through the downregulation of CD4 expression.Copyright © 2001 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]