Clonality analysis of fibroblast proliferation in patients with idiopathic pulmonary fibrosis / 대한내과학회지

BACKGROUND/AIMS: Idiopathic pulmonary fibrosis (IPF) is defined pathologically by usual interstitial pneumonia (UIP), and contains characteristic discrete areas of fibroblasts, myofibroblasts, and newly formed collagen, termed "fibroblast foci". A new hypothesis postulates that IPF results from epithelial injury and abnormal wound repair without preceding chronic inflammation. We explored the hypothesis that fibroblasts in the fibroblast foci of IPF undergo neoplastic monoclonal proliferation rather than reactive polyclonal proliferation. METHODS: We obtained fibroblasts from 24 fibroblast foci in seven female patients with IPF, endothelial cells from ten plexiform lesions of two female patients with idiopathic pulmonary arterial hypertension (IPAH) as a positive control for monoclonality, and lung parenchymal cells by microdissection of each formalin-fixed paraffin-embedded block of lung. To analyze clonality, we performed the human androgen-receptor gene methylation assay (HUMARA). DNA released by protein K digestion was subjected to polymerase chain reaction (PCR) amplification with prior digestion with and without the methylation-sensitive restriction enzyme HhaI. Then, we calculated the clonality ratio after electrophoretic analysis of the PCR amplification product. A clonality ratio 0.25, suggesting polyclonality, whereas 7 of 10 plexiform lesions had clonality ratios <0.25 suggesting monoclonality. CONCLUSIONS: The polyclonality of the fibroblast foci in IPF suggests that the fibroblast proliferation in IPF is not neoplastic, but is reactive in nature

The Effects of Endothelin Receptor Antagonist on Hemodynamic and Respiratory Mechanics in Experimental Acute Pulmonary Thromboembolism / 결핵

BACKGROUND: Endothelin (ET) is the most potent vasoconstrictor and bronchoconstrictor. In patients with acute pulmonary thromboembolism (APTE), (delete) The plasma ET-1 level is elevated in patients with acute pulmonary thromboembolism (APTE). These findings suggest the possibility of ET-1 as an important mediator This finding suggest that ET-1 may be an important mediator in the cardiopulmonary derangement of APTE. But whether ET-1 is a pathogenic mediator or a simple marker of APTE is not known. We investigated the The role of ET-1 in the pathogenesis of cardiopulmonary dysfunction in APTE through evaluating (delete) was investigated through an evaluation of the effects of ETA-receptor antagonist on APTE. We also demonstrated that increased The increase in local levels of preproET-1 mRNA and ET-1 peptide in the embolized lung was also demonstrated. METHODS : In a canine autologous blood clot pulmonary embolism model, ETA-receptor antagonist (10 mg/kg intravenously, n = 6) was administered one hour after the onset of the embolism. Hemodynamic measurements, blood gas tensions and plasma levels of ET-1 immunoreactivity in this treatment group were compared with those in the control group (n = 5). After the experiment, preproET-1 mRNA expression (using Northern blot analysis) and the distribution of ET-1 (by immunohistochemical analysis) in the lung tissues were examined. RESULTS: Increase The increases in pulmonary arterial pressure and pulmonary vascular resistance were smaller in treatment group compared with of the treatment group were less than those of the control group. Decrease in cardiac output was also less in the treatment group. Complications such as systemic arterial hypotension and hypoxemia did not occur with the administration of ETA-receptor antagonist. While the The plasma level of ET-1 like (ED: what does 'like' mean?) immunoreactivity was increased after embolization in both the groups groups, it but was significantly higher in the treatment group. The preproET-1 mRNA and ET-1 peptide expressions were increased in the embolized lung. CONCLUSION: ET-1 synthesis increases with embolization in the lung and may plays play an important role in the pathophys iology of cardiopulmonary derangement of APTE. Also Furthermore, ETA-receptor antagonist attenuates cardiopulmonary alterations seen in APTE, suggesting a potentially beneficial effect a potential benefit of this therapy.

The Value of Interleukin-12 as an Activity Marker of Pulmonary Sarcoidosis / 결핵

BACKGROUND: Sarcoidosis is a chronic granulomatous inflammatory disease of unknown etiology often involving the lungs and intrathoracic lymph nodes. The natural course of sarcoidosis is variable from spontaneous remission to significant morbidity or death. But, the mechanisms causing the variable clinical outcomes or any single parameter to predict the prognosis was not known. In sarcoidosis, the number and the activity of CD4+ lymphocytes are significantly increased at the loci of disease and their oligoclonality suggests that the CD4+ lymphocytes hyperreactivity may be caused by persistent antigenic stimulus. Recently, it has been known that CD4+ lymphocytes can be subdivided into 2 distinct population(Th1 and Th2) defined by the spectrum of cytokines produced by these cells. Th1 cells promote cellular immunity associated with delayed type hypersensitivity reactions by generating IL-2 and IFN-gamma. Th2 cells play a role in allergic responses and immediate hypersensitivity reactions by secreting IL-4, IL-5, and IL-10. CD4+ lymphocytes in pulmonary sarcoidosis were reported to be mainly Th1 cells. IL-12 has been known to play an important role in differentiation of undifferentiated naive T cells to Th1 cells. And, Moller et al. observed increased IL-12 in BALF in patients with sarcoidosis. So it is possible that the elevated level of IL-12 is necessary for the continuous progression of the disease in active sarcoidosis. This study was performed to test the assumption that IL-12 can be a marker of active pulmonary sarcoidosis. METHODS : We measured the concentration of IL-12 in brochoalveolar lavage fluid(BALF) and in conditioned medium of alveolar macrophage(AM) using ELISA(enzyme-linked immunosorbent assay) method in 26 patients with pulmonary sarcoidosis (10 males, 16 females, mean age : 39.8 +/-2.1 years) and 11 normal control. Clinically, 14 patients had active sarcoidosis and 12 patients had inactive. RESULTS: Total cells counts, percentage and number of lymhocytes, number of AM and CD4/CD8 lymphocyte ratio in BALF were significantly higher in patients with sarcoidosis than in control group. But none of these parameters could differentiate active sarcoidosis from inactive disease. The concentration of IL-12 in BALF was significantly increased in sarcoidosis patients (49.3+/-9.2 pg/ml) than in normal control (2.5+/-0.4 pg/ml) (p<0.001). Moreover it was significantly higher in patients with active sarcoidosis (70.3+/-14.8 pg/ml) than in inactive disease (24.8+/-3.1 pg/ml) (p=0.001). Also, the concentration of IL-12 in BALF showed significant correlation with the percentage of AM(p<0.001), percentage(p<0.001) and number of lymphocyte (p<0.001) in BALF, suggesting the close relationship between the level of IL-12 in BALF and the inflammatory cell infiltration in the lungs. Furthermore, we found a significant correlation between the level of IL-12 and the concentration of soluble ICAM-1: in serum (p<0.001) and BALF (p=0.001), and also between IL-12 level and ICAM-1 expression of AM (p<0.001). The AM from patients with pulmonary sarcoidosis secreted significantly larger amount of IL-12 (206.2+/- 61.9 pg/ml) than those of control (68.3+/-43.7 pg/ml) (p<0.008), but, there was no difference between inactive and active disease group. CONCLUSION: Our data suggest that the BALF IL-12 level can be used as a marker of the activity of pulmonary sarcoidosis.

Study on the Clonality of Endothelial Cell Proliferation in Plexiform Lesions in Patients with Pulmonary Hypertension Associated with CREST Syndrome / 결핵

BACKGROUND: The CREST syndrome is an indolent form of progressive systemic sclerosis. Although its clinical progress is indolent, pulmonary hypertension(PH) associated with CREST syndrome have grave prognosis with over 40 percent mortality rate at 2 year follow-up. But the pathogenesis of pulmonary hypertension in this disease is not known, and classified as either primary or secondary PH. Clonality of endothelial cell proliferation in plexiform lesion is a molecular marker which allows distinction between primary and secondary PH. We performed this study to know whether the PH associated with CREST syndrome is a variant of primary PH or is a secondary PH. METHODS: We assessed the X-chromosome inactivation based on the methylation pattern of the human androgen-receptor gene by PCR(HUMARA). Endothelial cells in plexiform lesions from female patients(n=3) with PH associated with CREST syndrome were microdissected from paraffin blocks. Vascular smooth muscle cells and lung parenchyma were also microdissected for clonality studies. RESULTS: The proliferating endothelial cells in 14 plexiform lesions were all polyclonal. Similarly proliferated smooth muscle cells from 5 vessels with medial hypertrophy were also polyclonal. CONCLUSION: These results suggest that the pulmonary hypertension associated with CREST syndrome has different pathogenesis from primary PH and to be classified as secondary PH.