BAL neopterin : a novel marker for cell-mediated immunity in patients with pulmonary tuberculosis and lung cancer.

BACKGROUND: Neopterin is derived from guanosine triphosphate and is produced by stimulated macrophages under the influence of gamma-interferon of lymphocyte origin. It has been suggested that it is an excellent marker for the activation of the monocyte/macrophage axis in some clinical situations. However, to our knowledge, the relationship of BAL neopterin levels to disease states has not been studied. AIM: To assess the usefulness of BAL neopterin levels as an index of disease activity in patients with pulmonary tuberculosis and lung cancer. METHODS: BAL and serum neopterin levels were evaluated in 20 patients with pulmonary tuberculosis, 20 patients with bronchogenic carcinoma, and 10 healthy individuals. The concentration of neopterin was evaluated by radioimmunoassay technique. The BAL level of neopterin was standardized using the BAL urea level. RESULTS: The neopterin levels (mean +/- SD) in the BAL and serum of tuberculous patients (88.6 +/- 27.4 nmol/L epithelial lining fluid [ELF], 61.3 +/- 29.4 nmol/L, respectively) were significantly higher when compared with those in lung cancer patients (40.7 +/- 16.6 nmol/L ELF, 26.8 +/- 6.58 nmol/L, respectively, p < 0.001) and when compared with those in control subjects (26.3 +/- 11.3 nmol/L ELF, 6.8 +/- 2.7 nmol/L, respectively, p < 0.001). In the tuberculous group, BAL and serum neopterin levels in patients with far-advanced disease were significantly higher when compared with those in patients with moderately and minimally advanced diseases (p < 0.001). BAL and serum neopterin levels were significantly higher in patients with small cell carcinoma than in those with adenocarcinoma (p < 0.05). BAL neopterin levels were significantly (p < 0.001) higher than serum levels in all patients and control groups. In addition, there were significant positive correlations between BAL and serum neopterin levels in tuberculous (r = 0.92, p < 0.001), lung cancer (r = 0.62, p < 0.001), and control groups (r = 0.93, p < 0.001). CONCLUSIONS: The levels of neopterin in BAL fluid may reflect the degree of disease activity in pulmonary tuberculous patients. In addition, BAL neopterin levels are elevated in patients with lung cancer, especially the small-cell carcinoma type.

Monoclonal anti-CEA antibodies in the discrimination between primary pulmonary adenocarcinoma and colon carcinoma metastatic to the lung.

Lung metastases from colon adenocarcinoma are often difficult to differentiate from primary lung adenocarcinoma. We studied the diagnostic value of a polyclonal anti-CEA antiserum and two monoclonal anti-CEA antibodies (B18, D14) which define antigens overexpressed in colon carcinoma. Autopsy material from 20 patients with colon carcinoma and lung metastases and 20 specimens from patients with primary lung adenocarcinoma were retrieved, stained, and interpreted without knowledge of the origin of the lung tumor. Colon carcinomas, lung metastases and lung primaries stained positively with polyclonal anti-CEA in 90-100% of cases. D14 stained 75% of colonic metastases and 70% of primary lung adenocarcinomas, whereas 95% of colon primaries were positive. Sixty-five percent of colon primaries and 50% of their metastases were positive with B18, whereas 45% of lung primaries were positive. The frequency of B18 positivity was significantly greater in those colon primaries that were surgically derived (7/9, 78%) compared with their autopsy-derived lung metastases (2/9, 22%) (P less than 0.05). Similarly, D14 staining in surgically derived colon primaries (9/9, 100%) was significantly greater than their autopsy-derived lung metastases (5/9, 56%) (P less than 0.05). In surgical/biopsy-derived tissues 9/9 colonic primaries were D14-positive, whereas only 1 of 6 lung primaries was positive (P = 0.002). We conclude that D14 and polyclonal anti-CEA both stain the majority of colon adenocarcinomas and that changes associated with prolonged fixation may reduce the positivity rate with both B18 and D14 monoclonal antibodies. All three antibodies stain autopsy-derived tissue from primary lung cancer to a significant degree.(ABSTRACT TRUNCATED AT 250 WORDS)