Idiopathic pulmonary fibrosis (IPF) is a fatal disorder without an effective therapy to date. In a double-blind, randomized, placebo-controlled trial, 107 patients were prospectively evaluated for efficacy of a novel compound, pirfenidone. The difference in the change in the lowest oxygen saturation by pulse oximetry (SpO2) during a 6-minute exercise test, the primary endpoint, from baseline to 6 months was not significant between the two groups (p = 0.0722). In a prespecified subset of patients who maintained a SpO2 greater than 80% during a 6-minute exercise test at baseline, the lowest SpO2 improved during a 6-minute exercise test in the pirfenidone group at 6 and 9 months (p = 0.0069 and 0.0305, respectively). Positive treatment effect was demonstrated in secondary endpoints: (1) change in VC measurements at 9 months (p = 0.0366) and (2) episodes of acute exacerbation of IPF occurring exclusively in the placebo group during the 9 months (p = 0.0031). Significant adverse events were associated with pirfenidone; however, adherence to treatment regimen was similar between pirfenidone and placebo groups. In conclusion, treatment with pirfenidone improved VC and prevented acute exacerbation of IPF during the 9 months of follow-up. Future long-term studies are needed to clarify the overall safety and efficacy of pirfenidone in IPF.

Idiopathic pulmonary fibrosis (IPF) is a progressive, life-threatening, interstitial lung disease of unknown etiology. For optimal therapeutic management of IPF an accurate tool is required for discrimination between reversible and irreversible types of the disease. However, such noninvasive tools are few, and even with high-resolution computed tomography (HRCT), which is the most trusted method for doing so, the nature of the disease activity in IPF cannot always be accurately predicted. The aims of the present study were to assess the values of surfactant protein (SP)-A and SP-D in semiquantifying the extent of disease in IPF and in predicting deterioration in restrictive pulmonary function and survival over a follow-up period of 3-yr. SP-A and SP-D in sera were measured with enzyme-linked immunosorbent assays as previously described. Fifty-two IPF patients were studied to evaluate the association between serum SP-A and SP-D and disease extent on HRCT, deterioration in pulmonary function, and survival during 3 yr of follow-up. Both SP-A and SP-D concentrations were significantly correlated with the extent of alveolitis (a reversible change), whereas they did not correlate with the progression of fibrosis (an irreversible change). The SP-D concentration, unlike that of SP-A, was also related to the extent of parenchymal collapse and the rate of deterioration per year in pulmonary function. The concentrations of SP-A and SP-D in patients who died within 3 yr were significantly higher than in patients who were still alive after 3 yr. We propose that assays of SP-A and SP-D in sera from IPF patients are useful tools for understanding some pathologic characteristics of the disease, that SP-D may be a good predictive indicator of the rate of decline in pulmonary function, and that a combination of the assays for SP-A and SP-D may be helpful in predicting the outcome of patients with IPF.

Pulmonary surfactant protein D (SP-D) is a hydrophilic glycoprotein with a reduced molecular mass of 43 kDa and a member of the C-type lectin superfamily, along with mannose-binding proteins and surfactant protein A (SP-A). We have recently prepared monoclonal antibodies against human SP-D and developed an enzyme-linked immunosorbent assay (ELISA). In this study, the levels of SP-D in sera and bronchoalveolar lavage (BAL) fluids of patients with lung diseases were determined by ELISA, using human recombinant SP-D as a standard. We demonstrated that the concentrations of SP-D in sera are prominently increased in patients with idiopathic pulmonary fibrosis (IPF), interstitial pneumonia with collagen disease (IPCD), and pulmonary alveolar proteinosis (PAP). Patients with IPF, IPCD, and PAP exhibited levels of serum SP-D 5.1-fold, 7.2-fold, and 7.0-fold, respectively, of those in healthy volunteers; 91.5% of the patients with IPF, 81.3% with IPCD, and 100% with PAP exhibited serum SP-D levels that exceeded the cut-off value (mean + 2 SD of control value). Serum SP-D levels appeared to reflect the disease activity of IPF and IPCD and the disease severity of PAP. High levels of SP-D in BAL fluids were shown in patients with PAP, but not with IPF and IPCD. We conclude that measurement of SP-D in sera can provide an easily identifiable and useful clinical marker for the diagnosis of IPF, IPCD, and PAP, and can predict the disease activity of IPF and IPCD and the disease severity of PAP.

Cigarette smoking has diverse effects on the structure and function of the lung. Smoking appears to reduce the levels of Clara cell 10 kDa protein (CC10) in the alveolar lining fluid, but the influence of smoking serum on CC10 levels is still debated, and it has not been clear whether smoking reduces the number of CC10-producing lung cells. The aims of this study were to clarify the influence of smoking on CC10 levels in the alveolar lining fluid and bloodstream, and on the number of CC10-producing lung cells.CC10 concentrations were measured in sera and bronchoalveolar lavage (BAL) fluids, by means of enzyme-linked immunosorbent assay using monoclonal and polyclonal antibody, and the immunohistochemical expression of CC10 was examined in the lungs of nonsmokers and smokers using the monoclonal antibody, TY-5, against CC10/human urinary protein-1. CC10 concentrations in sera and in BAL fluids from healthy smokers were significantly lower than in healthy nonsmokers. Immunohistochemical expression of CC10 was found exclusively in nonciliated bronchiolar epithelial cells. As compared to that of nonsmokers, the mean percentage of CC10-positive bronchiolar epithelial cells was significantly decreased in lung tissue specimens obtained from smokers who had normal results in pulmonary function tests.It was concluded that smoking reduces the proportion of Clara cell 10 kDa protein-producing bronchiolar epithelial cells, resulting in decreased levels of Clara cell 10 kDa protein in the lower respiratory tract and in the bloodstream. The protein is a new blood biochemical and immunohistochemical marker, reflecting structural changes in peripheral airways induced by cigarette smoking.

Tumor growth and metastasis are angiogenesis-dependent processes initiated and regulated by a number of cytokines. Vascular endothelial growth factor (VEGF) is a potent angiogenic protein with a selective mitogenic effect on vascular endothelial cells. Osteopontin (OPN) induces endothelial cell migration and upregulates endothelial cell migration induced by VEGF. To clarify the cooperative role of VEGF and OPN in tumor angiogenesis, we stained VEGF, OPN, and CD34 immunohistochemically in 87 cases of stage I non-small cell lung cancer (adenocarcinoma, 55, and squamous cell carcinoma, 32). Of the 87 patients studied, 27 patients had postoperative relapse and 60 patients did not. VEGF was found in 34 of 55 cases of adenocarcinomas and 14 of 32 squamous cell carcinomas, and OPN was found in 30 of 55 adenocarcinomas and 10 of 32 squamous cell carcinomas. In adenocarcinoma, microvessel counts of VEGF-positive and OPN-positive tumors were significantly higher than VEGF-negative and OPN-negative tumors, respectively, whereas in squamous cell carcinoma they were not. More importantly, patients with VEGF- and OPN-positive stage I lung adenocarcinoma had significantly worse prognosis as compared with other groups. Cooperation of OPN is important in VEGF-mediated tumor angiogenesis in stage I lung adenocarcinoma.