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L Orre

Publications and source records attributed to L Orre.

6 recordsLinked to original sources
PubMed2001

Functional and morphological differences between human alveolar and interstitial macrophages.

Macrophages play an essential role in pulmonary host defense. They are, however, a heterogeneous cell population located in different lung compartments. This study was designed to elucidate differences between two macrophage populations obtained from the human lung, i.e., alveolar macrophages (AM) and interstitial macrophages (IM). Macroscopically tumor-free lung segments from nine patients undergoing lobectomy or pulmectomy were studied. All patients had a diagnosis of primary lung cancer. AM were recovered by bronchoalveolar lavage and IM were isolated by mechanical fragmentation of the lavaged lung segments followed by enzymatic treatment. The cell fractions were analyzed with respect to morphology (transmission electron microscopy) and function (phagocytosis). The cells in the IM fraction were smaller (7.6 +/- 1.8 microm (mean +/- SD) compared with 16.0 +/- 4.1 microm) and morphologically more heterogeneous than those in the AM fraction. Interestingly, a considerable portion of the cells in the IM fraction had a typical AM-like appearance. Despite this, the AM fraction had a higher phagocytic activity compared to IM, with faster attachment and ingestion processes (P <0.001 for both). We conclude that the heterogeneity of human lung macrophages must be taken into consideration when their role in the inflammatory response is studied.

Aged↗
PubMed1998

Improved lung function and quality of life following increased elastic recoil after lung volume reduction surgery in emphysema.

Lung volume reduction surgery for severe emphysema with removal of 20-30% of the most destroyed parts of the lung parenchyma has been reported to improve lung function substantially. Increased elastic recoil has been suggested as one underlying mechanism for the improvement. Fourteen patients, seven men and seven women with a mean age of 62 years, who underwent bilateral lung volume reduction surgery have been followed up for 3 months. We here report the data on quality of life, lung function and elastic recoil. FEV1.0 increased by a mean of 26% from 0.581 to 0.731 (P < 0.01). The mean TLC was reduced by 16% from 8.91 to 7.51 (P < 0.001). The level of hyperinflation decreased as implied by a reduction in the ratio of RV to TLC from 0.70 to 0.60 (P < 0.001). The pulmonary elastic recoil improved, with an increase in the transpulmonary pressure at maximal inspiration (PelTLC) from 0.95 kPa to 1.35 kPa (P < 0.05) and an average increase in the coefficient of retraction PelTLC/TLC) from 0.12 kPa l-1 to 0.19 kPa l-1 (P < 0.01). The resting PaO2 increased from a mean of 8.7 kPa to 9.8 kPa (P < 0.01). The patients reported a high degree of subjective improvement according to the St. George's Respiratory Questionnaire and the working capacity on a bicycle increased by 26% from a mean of 38 W to 48 W (P < 0.01). The promising short-term results of lung volume reduction surgery for severe emphysema appear to be related to improved pulmonary elastic recoil.

Aged↗
PubMed1995

Immunogenicity and immunosensitivity of ex vivo human carcinomas: interferon gamma and tumour necrosis factor alpha treatment of tumour cells potentiates their interaction with autologous blood lymphocytes.

Human carcinoma cells vary appreciably in the expression of MHC class I, class II, ICAM-1 (CD54) and B7 (CD80) molecules. Short-term in vitro exposure of ex vivo carcinoma cells to interferon gamma and tumour necrosis factor alpha elevated/induced the surface expression of MHC class I, class II and ICAM-1, but only rarely of B7. We found that cytokine treatment elevated the cytotoxic susceptibility and the stimulatory potential of ex vivo tumour cells. This was demonstrated (a) by the increased frequency and elevated level of auto-tumour lysis and (b) by induction of DNA synthesis and generation of cytotoxic lymphocytes in autologous mixed lymphocyte/tumour cell culture (MLTC). The MHC class I and ICAM-1 molecules on the tumour cells were required for interaction with the lymphocytes as indicated by the inhibitory effect of specific mAb both in the stimulation and in the cytotoxic tests. While the cytokine-induced increases in MHC and ICAM-1 on the low-expression tumours were probably important for the modification of functional interaction with the autologous lymphocytes, it is likely that alterations in other properties of tumour cells were also induced which contributed to the phenomenon. This was indicated by the results obtained with several tumours, which expressed indigenously high levels of these molecules but activated the autologous lymphocytes only after cytokine treatment. In several experiments the untreated targets that did not activate the lymphocytes were sensitive to the cytotoxicity of the effectors activated in MLTC. The results show that the afferent and efferent arms of the immune response have different requirements for functional interactions between lymphocytes and tumour cells.

Antibodies, Neoplasm↗