Serial Measurements of Plasma Hepatocyte Growth Factor in Patients with Pneumonia Following Cancer Chemotherapy

Hepatocyte growth factor levels in Legionella pneumonia: a retrospective study

BACKGROUND

Hepatocyte growth factor (HGF) is known to be involved in the resolution of pulmonary inflammation and repair of acute lung injury. Legionella pneumonia is sometimes complicated by acute lung injury. Our study aimed to determine the role of serum HGF levels in Legionella pneumonia.

METHODS

Sera from patients with Legionella pneumonia (42 cases), other bacterial pneumonia (33 cases), pulmonary tuberculosis (19 cases), and normal controls (29 cases) were collected. The serum HGF levels for each serum sample were determined by sandwich ELISA. Clinical and laboratory data were collected by reviewing the medical charts.

RESULTS

Serum HGF levels were higher in patients with Legionella pneumonia than in those with other bacterial pneumonia, pulmonary tuberculosis, and controls. The HGF levels were compared with white blood cell counts, C-reactive protein, Alanine amino-transferase, and lactate dehydrogenase (LDH). The HGF levels were correlated to serum LDH levels. Moreover, serum HGF levels were significantly higher in non-survivors than in survivors.

CONCLUSIONS

HGF levels increased in severer pneumonia caused by Legionella, suggesting that HGF might play a significant role in the Legionella pneumonia.

Measurement of hepatocyte growth factor in serum and bronchoalveolar lavage fluid in patients with pulmonary fibrosis

The present study evaluated the clinical significance of hepatocyte growth factor (HGF) in patients with pulmonary fibrosis. Twenty-one patients with a diagnosis of pulmonary fibrosis [14 with idiopathic pulmonary fibrosis (IPF) and seven with pulmonary fibrosis associated with a collagen vascular disorder (PF-CVD]) and 21 normal subjects as control were studied. HGF levels in sera of patients with pulmonary fibrosis (0.34 +/- 0.02 ng ml-1) were elevated significantly as compared with normal subjects (0.21 +/- 0.01 ng ml-1) (P < 0.0001). HGF/albumin levels in broncho-alveolar lavage fluid (BALF) of patients with pulmonary fibrosis (72 +/- 17 ng g-1 albumin) were also significantly elevated as compared with normal subjects (under the detection limit) (P < 0.01). HGF levels in sera correlated significantly with elastase levels in sera and C-reactive protein, and correlated negatively with PaO2. HGF levels in sera were significantly higher in smokers with pulmonary fibrosis (0.42 +/- 0.03 ng ml-1) as compared with non-smokers with pulmonary fibrosis (0.29 +/- 0.03 ng ml-1) (P < 0.005). HGF/albumin levels in BALF correlated significantly with elastase/albumin levels in BALF, lactate dehydrogenase/albumin in BALF, Immunoglobulin A/albumin in BALF, total cell count/albumin in BALF, total number of alveolar macrophage/albumin in BALF, total number of neutrophil/albumin in BALF, CEA/albumin in BALF, CA19-9/albumin in BALF, and SCC/albumin in BALF. These results suggest that following lung injury, HGF may be a mediator involved in the repair which leads to pulmonary fibrosis.

Hepatocyte growth factor and neutrophil elastase in idiopathic pulmonary fibrosis

It has been hypothesized that hepatocyte growth factor (HGF) may play an important role in regulating the growth of lung epithelium and in the regeneration of the lung as a paracrine or endocrine factor in idiopathic pulmonary fibrosis (IPF). Based on this background, serum HGF was measured in 31 IPF patients (21 male/10 female, median age 60 years). Fifteen age-matched normal non-smokers served as the control. Hepatocyte growth factor was measured by enzyme-linked immunosorbent assay with monoclonal and polyclonal antibodies against human HGF (Otsuka Assay Laboratories, Tokushima, Japan). Elastase: alpha 1-proteinase complex was also measured by enzyme-linked immunosorbent assay. No patients had significant liver or renal dysfunction. As a result, mean (standard error) serum HGF concentration of the patients with IPF was 0.384 (0.022) ng ml-1, which was significantly high compared to normal non-smokers [0.213 (0.012) ng ml-1, P < 0.001, 95% confidence interval was between 0.104 and 0.238]. Serum HGF values correlated strongly with the plasma elastase: alpha 1 proteinase inhibitor complex (R = 0.679, P < 0.001). Immunohistochemical staining of lung tissue with anti-human neutrophil elastase showed scattered immunopositive cells mainly in interstitium. Immunohistochemical staining with mouse anti-human HGF antibody showed that HGF was distributed to the lung epithelial cells in IPF lung specimens obtained by open lung biopsy. These results suggest that HGF may play an important role in the pathogenesis of IPF.