Naomi Dobashi

Pathological and radiological changes in resected lung specimens in Mycobacterium avium intracellulare complex disease

The present study was designed to evaluate the pathological and immunohistochemical findings of Mycobacterium avium intracellulare complex (MAC) lung infection. A retrospective study was performed in five cases with positive cultures for MAC in whom lung resections were performed between January 1989 and December 1996. A determination of whether or not MAC caused pulmonary disease was made using the 1997 criteria defined by the American Thoracic Society. In addition, MAC was cultured from all of the five lung specimens. Pathological and immunohistochemical findings as well as chest computed tomography (CT) findings were evaluated in these five patients. Pathological findings of bronchiectasis, bronchiolitis, centrilobular lesion, consolidation, cavity wall and nodules were demonstrated, respectively, in relation to chest CT findings. Extensive granuloma formation throughout the airways was clearly demonstrated. Immunohistochemical staining demonstrated: 1) epithelioid cells and giant cells; 2) myofibroblasts extensively infiltrating the cavity wall; and 3) B-cells detected in aggregates in the vicinity of the epithelioid granulomas. This study identified pathological and immunohistochemical characteristics of Mycobacterium avium complex infection relative to chest computed tomography findings and allowed the conclusion that bronchiectasis and bronchiolitis were definitely caused by Mycobacterium avium complex infection.

The role of caspase 3 in producing cytokeratin 19 fragment (CYFRA21-1) in human lung cancer cell lines

The CYFRA 21‐1 assay, which detects cytokeratin 19 (CK19) fragment, is widely used as a tumor marker for lung cancer, particularly non‐small cell lung cancer. However, the reason that some lung cancer cell lines release CYFRA 21‐1 in culture supernatants and others do not remains unclear. We hypothesized that the release of CYFRA 21‐1 might be related to the expression of CK19 and caspase 3. In order to prove this, the quantities of mRNA for CK19 were evaluated by the competitive reverse transcriptase‐polymerase chain reaction (RT‐PCR). CK19 protein synthesis was also evaluated by Western blotting and immunohistochemistry, and the levels of CYFRA 21‐1 in the culture supernatant were measured by an immunoradiometric assay. The expression of mRNA for caspase 3 was evaluated by the RT‐PCR, and caspase 3 protein synthesis was also evaluated by immunohistochemistry. In 13 lung cancer cell lines, the amounts of mRNA for CK19 correlated with the levels of CYFRA 21‐1 in culture supernatants, results of Western blotting for CK19, and positivities of immunohistochemistry for CK19. In 5 cell lines that produced a significant amount of CYFRA 21‐1, the level of CYFRA 21‐1 correlated with the positivity of RT‐PCR for caspase 3 and immunohistochmistry for caspase 3. This suggests that caspase 3 played a role in the formation of CYFRA 21‐1. In addition, the specific inhibitor of caspase 3 significantly inhibited the release of CYFRA 21‐1 in culture supernatants. In conclusion, we demonstrate that caspase 3, which cleaves several intermediate filaments and carries out cell apoptosis, played an important role in producing CYFRA 21‐1 in human lung cancer cell lines.

Circulating Cytokeratin 8:Anti-Cytokeratin 8 Antibody Immune Complexes in Sera of Patients with Pulmonary Fibrosis

Background: It has been suggested that the humoral immune system plays a role in the pathogenesis of idiopathic pulmonary fibrosis (IPF) and pulmonary fibrosis associated with collagen vascular disorders (PF-CVD). Although circulating immune complexes in patients’ sera have been suggested, none of the antigens have been characterized. Objectives: The purpose of this study is to characterize the antigen of the immune complexes in patients’ sera of pulmonary fibrosis. Methods: As we previously established that one of the antibodies against A549 cells (lung alveolar type II cells) was anti-cytokeratin 8 (CK8), we confirmed the existence of anti-CK8 antibody in patients’ sera by Western immunoblot. In addition, we tried to demonstrate circulating CK8:anti-CK8 immune complexes in patients’ sera by Western immunoblot. Furthermore, we established an enzyme-linked immunosorbent assay to quantitate CK8:anti-CK8 immune complexes. Results: In patients with pulmonary fibrosis, anti-CK8 antibodies were clearly demonstrated in sera by Western immunoblot. In addition, circulating CK8:anti-CK8 immune complexes were also clearly demonstrated by Western immunoblot. It was possible to establish ELISA to quantitate CK8:anti-CK8 immune complexes. If the cutoff value, which was determined based on the highest value of normal volunteers, was introduced, high CK8:anti-CK8 antibody complexes were demonstrated in 9 of 31 patients (29.0%) with IPF and PF-CVD. Conclusions: This is the first study to clarify the antigen of the circulating immune complex in sera of patients with IPF. These results suggest that circulating CK8:anti-CK8 immune complexes may have played a role in the process of lung injury in pulmonary fibrosis.

Detection of anti-cytokeratin 8 antibody in the serum of patients with cryptogenic fibrosing alveolitis and pulmonary fibrosis associated with collagen vascular disorders

BACKGROUND It has been suggested that the humoral immune system plays a role in the pathogenesis of cryptogenic fibrosing alveolitis (CFA). Although circulating autoantibodies to lung protein(s) have been suggested, none of the lung proteins have been characterised. The purpose of this study was to determine the antigen to which the serum from patients with pulmonary fibrosis reacted. METHODS The anti-A549 cell antibody was characterised in a patient with CFA using Western immunoblotting and immunohistochemical staining of A549 cells. As we identified that one of the antibodies against A549 cells was anti-cytokeratin 8, the expression of mRNA of cytokeratin 8 in A549 cells was evaluated. In addition, we attempted to establish an enzyme linked immunosorbent assay to measure the levels of anti-cytokeratin 8 antibody in the serum of patients with CFA and pulmonary fibrosis associated with collagen vascular disorders (PF-CVD). RESULTS Initially two anti-A549 cell antibodies were detected in the serum of patients with pulmonary fibrosis, one of which was characterised as anti-cytokeratin 8 antibody by Western immunoblotting. We were able to establish an ELISA to measure anti-cytokeratin 8 antibody and found significantly higher levels in patients with CFA and PF-CVD than in normal volunteers, patients with sarcoidosis, pneumonia, and pulmonary emphysema. CONCLUSIONS One of the anti-A549 cell antibodies in the serum of patients with CFA was against cytokeratin 8. The serum levels of anti-cytokeratin 8 antibody were increased in patients with CFA and PF-CVD. These results suggest that anti-cytokeratin 8 antibody may be involved in the process of lung injury in pulmonary fibrosis.

Detection of anti-ADAM 10 antibody in serum of a patient with pulmonary fibrosis associated with dermatomyositis.

OBJECTIVES It has been suggested that the humoral immune system plays a part in the pathogenesis of pulmonary fibrosis. Although circulating autoantibodies to lung protein(s) have been suggested, few lung proteins have been characterised. The purpose of this study is to determine the antigen recognised by serum of a patient with pulmonary fibrosis associated with dermatomyositis. METHODS To accomplish this, anti-small airway epithelial cell (SAEC) antibody in a patients serum was evaluated using a western immunoblot. RESULTS An autoantibody against SAEC was found, and the antigen had a molecular weight of 62 kDa. Using the patients serum, clones from the normal lung cDNA library were screened and demonstrated that anti-SAEC antibody in the patients serum was against ADAM (A disintegrin and metalloprotease) 10. CONCLUSION This is the first report that demonstrates the existence of anti-ADAM 10 antibody in a patient with pulmonary fibrosis associated with dermatomyositis.

Expression of cytokeratin 19 mRNA in human lung cancer cell lines

The present study was designed to clarify the mechanism by which some lung cancer cell lines can produce cytokeratin 19 (CK19) fragment and others cannot. We hypothesized that some lung cancer cell lines which cannot release CK19 express an incomplete sequence of CK19 mRNA. Expression of mRNA was evaluated by RT‐PCR using several primer pairs for CK19. CK19 in the culture supernatant was measured by an immuno‐radiometric assay. CK19 protein synthesis was evaluated by Western immunoblot and immuno‐histochemistry. Among 16 lung cancer cell lines, 7 released significant amounts of CK19 in the supernatant. In some cell lines, expression of CK19 mRNA was observed only in some combinations of primers, suggesting that incomplete mRNA was expressed. 3′‐RACE analysis detected amplified products of a shorter size compared with normal amplified products in cell lines which expressed incomplete CK19 mRNA, suggesting that 3′‐ends of mRNA for CK19 were deleted. Results of Western immunoblot and immuno‐histochemical staining using anti‐human CK19 monoclonal antibody completely correlated with the results on CK19 levels in culture supernatants as well as with complete expression of mRNA. We conclude that levels of CK19 closely relate to the expression of complete mRNA for CK19. Int. J. Cancer 81:939–943, 1999.

Detection of large molecular weight cytokeratin 8 as carrier protein of CA19-9 in non-small-cell lung cancer cell lines.

It has been reported that cytokeratin 8 (CK8) is expressed in all non-small-cell lung cancers (NSCLC). We hypothesized that antigenic changes of CK8 may occur in some NSCLC cell lines. To prove this, Western immunoblot analysis using anti-human CK8 monoclonal antibodies as well as immunohistological staining of CK8 were performed in NSCLC cell lines. As a result, CK8 which had a higher molecular weight than recombinant CK8 was demonstrated in two of eight NSCLC cell lines. In addition, this CK8 contained antigenic epitopes of CA19–9. This CK8 with higher molecular weight, may have played a role in the process of invasion or metastasis of NSCLC.

Increased intensity of lung infiltrates at the side of lung cancer in patients with lung cancer associated with pulmonary fibrosis

It has been reported that lung cancer is frequently associated with idiopathic pulmonary fibrosis (IPF). The purpose of this study was to compare the intensity of lung infiltrates between the side associated with lung cancer and the side without lung cancer. Twenty-three patients (24 lung cancers) with primary lung cancer associated with pulmonary fibrosis were retrospectively evaluated. Chest CT findings were evaluated by three expert radiologists using the intensity scores. In 16 of the 23 patients, it was possible to compare the intensity of lung infiltrates between both sides of the lungs. As a result, increased intensity at the side in which lung cancer developed was demonstrated in 12 of 16 patients (75%). In the remaining four patients, intensity of lung infiltrates was the same in both lungs. In operated patients as well as autopsied patients, it was possible to evaluate the pathological findings of lung tissues around cancer cells. This study clearly demonstrates that the intensity of lung infiltrates increased at the side in which lung cancer developed.

Elevation of cytokeratin 19 fragment in serum in patients with hepatoma: its clinical significance.

Objectives Cytokeratin 19 fragment (CK19) levels in serum have already been documented as a useful tumour marker for lung cancer. In the present study, we hypothesize that CK19 may be increased in serum from patients with hepatoma. Methods We measured the CK19 levels in serum from patients with hepatoma and evaluated the correlation between CK19 level and each clinical parameter. We studied 70 patients diagnosed with hepatoma, and used 14 patients with chronic hepatitis C and 45 patients with liver cirrhosis as controls. Results In 33 of 70 patients (47.1%) with hepatoma, the serum CK19 level was elevated to above the normal range. CK19 levels in serum from patients with hepatoma were significantly correlated with levels of α-fetoprotein and prothrombin induced by vitamin K absence for factor II (PIVKA-II). In 57 patients with hepatoma in whom both CK19 and α-fetoprotein were measured, only CK19 was elevated in seven patients (12.3%). Immunohistochemical studies using hepatoma tissues demonstrated that hepatoma cells were stained by anti-human CK19 antibody. We also demonstrated that the HepG2 cell line expressed CK19. Conclusions Our data demonstrate that hepatomas aberrantly express CK19, and that measurement of CK19 might be a useful tumour marker in diagnosing hepatoma.