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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.

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

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

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.