Changes in pulmonary histology and exfoliated bronchoalveolar cells induced by in vivo introduction of the tumor necrosis factor-alpha gene.

An inflammatory cytokine, tumor necrosis factor (TNF)-alpha, has been implicated in the pathogenesis of inflammatory lung diseases such as interstitial pneumonia (IP). To clarify the role of the inflammatory cytokine in the pathogenesis of lung inflammation, we introduced a murine TNF-alpha gene into murine lungs by the hemagglutinating virus of Japan (HVJ)-liposome method. Seven days after the TNF-alpha gene introduction resulted in marked cellular infiltration of alveoli, and mild histological change was observed 28 days after the gene introduction. Electron microscopic analysis revealed minimal deposition of collagen fibrils. Analysis of the BAL revealed that the total cell number was markedly increased 3 and 7 days after the gene introduction, and more than 90% of the cells were macrophages. The increase in the cell number was returned to below the normal level 28 days after the gene introduction. During the development of IP, TNF-alpha may regulate pathologic change of the pulmonary interstitium and alveolar cells.

In vivo gene transfer of an extracellular domain of platelet-derived growth factor beta receptor by the HVJ-liposome method ameliorates bleomycin-induced pulmonary fibrosis.

A number of investigators have reported augmented expression of PDGF in lungs with idiopathic pulmonary fibrosis (IPF) or with other types of pulmonary fibrosis. To accomplish such a regulation of PDGF activity, we constructed an expression plasmid of the extracellular domain of PDGF receptor beta chain (XR), which lacks intracellular tyrosine kinase domain and transmembrane portions, and estimated the therapeutic effects of XR gene transfer through the trachea on bleomycin-induced lung fibrosis of C57BL/6 mice using the hemagglutinating virus of Japan(HVJ)-liposome method. The XR gene transfer ameliorated the increases in the wet weight and hydroxyproline content and the histopathologic changes of the lung induced by bleomycin. These findings suggest that PDGF plays a crucial role in the pathogenesis of pulmonary fibrosis, and that XR gene transfer using the HVJ-liposome method may limit the progression of pulmonary fibrosis.

Introduction of plasmid DNA and oligonucleotides into lung epithelial cells by the hemagglutinating virus of Japan (HVJ)-liposome method.

The hemagglutinating virus of Japan (HVJ) fused with liposomes provides a unique transfection vehicle with characteristics of both virus vector and liposome. Here we investigate the efficiency and safety of the HVJ-liposome technique in delivering foreign genes and oligonucleotides into the lung of the Wistar rat. A plasmid vector containing the Escherichia coli beta-galactosidase (beta-gal) gene and the chicken beta-actin promoter was transfected via the trachea using the HVJ-liposome method. Cytochemical staining showed expression of exogenous beta-gal activity in airway epithelial cells, alveolar macrophages, and alveolar type II cells. This activity persisted at least 28 days after administration of the genes. FITC-labeled oligonucleotides also were introduced into the same types of lung cells as those expressing beta-gal. After instillation of HVJ-liposome, anti-HVJ antibodies were detected in the sera of the rats, but even after repeated administration of HVJ-liposome, no marked histopathologic change was observed while exogenous beta-gal expression was detected in pulmonary cells.

[Diffuse alveolar hemorrhage after allogeneic bone marrow transplantation].

A 34-year-old woman with chronic myeloid leukemia underwent allogeneic bone marrow transplantation (BMT) after receiving high-dose chemotherapy and total body irradiation. She experienced progressively dry cough 51 days after BMT, and chest X-ray films showed patchy infiltrations in the lower fields of both lungs on the 66th day after BMT. The symptoms of cough, fever, and hypoxemia worsened. The patchy infiltrations continued to spread and fuse. Diffuse alveolar hemorrhage (DAH) was diagnosed on the basis of high-resolution CT and bronchoalveolar lavage findings. Treatment with high-dose methyl prednisolone pulse therapy, antibiotics, and haptoglobin resolved the patient's DAH symptoms. DAH was thought to be secondary to thrombotic microangiopathy. The majority of patients who experience DAH after BMT eventually die. The remission observed in our case was rare, and illustrated that steroid therapy can be effective for DAH after BMT.

Interleukin-6 secreting phaeochromocytoma associated with clinical markers of inflammation.

Phaeochromocytomas have been shown to produce not only catecholamines but other neuropeptides and hormones, with a variety of clinical manifestations. We report a 70-year-old female patient with phaeochromocytoma exhibiting sustained hypertension, low-grade fever, thrombocytosis, and elevated levels of plasma fibrinogen and C-reactive protein. Serum interleukin (IL)-6 levels were significantly elevated, whereas serum IL-1 alpha and IL-1 beta were not detectable. After surgical removal of the tumour, hypertension and low-grade fever disappeared, and the laboratory finding including serum IL-6 concentrations became normal. Immunohistochemical study of the tumour showed positive staining for IL-6. Culture of the resected tumour revealed the production of large amounts of IL-6. It is suggested that IL-6 secreted by the tumour was responsible for some of the clinical manifestations in this patient.

[Effects of in vivo instillation of genes coding for cytokines on pulmonary fibrosis].

Interstitial pneumonia is characterized by alveolitis that results in interstitial fibrosis. To study the role of humoral factors in the pathogenesis of interstitial fibrosis, we introduced expression vectors into Wistar rats via the trachea, to cause local overexpression of these humoral factors in the lung. Genes for human interleukin (IL)-6 and for the IL-6 receptor caused lymphocytic alveolitis without marked proliferation of fibroblasts. In contrast, overexpression of the genes for human transforming growth factor (TGF)-beta 1 and for human platelet-derived growth factor (PDGF)-B caused only mild cellular infiltration in the alveoli. However, both caused marked proliferation of fibroblasts and deposition of collagen fibrils. Introducing an expression vector that coded for a mutant form of the PDGF beta receptor that lacks its cytoplasmic domain markedly alleviated the pathohistologic changes caused by bleomycin in murine lungs. These findings show that TGF- and PDGF-B may be closely related to fibrosis in the lung, and that artificial regulation of them may be effective for treatment of lung fibrosis.

Lung cancer producing interleukin-6.

A patient with complaints of high fever and left shoulder pain was found to have a large mass in the left upper lobe on chest roentgenogram. Laboratory evaluation revealed marked thrombocytosis, hypoalbuminemia, and increased serum concentrations of CRP, fibrinogen and interleukin-6 (IL-6). A transcutaneous biopsy specimen revealed large cell carcinoma. Tumor production of IL-6 was confirmed by immunohistochemical staining with an anti-human IL-6 monoclonal antibody (MH60).