Biomedical subjects

M Damon

Publications and source records attributed to M Damon.

70 records · Page 4Linked to original sources

PubMed1982

Functional assessment of alveolar macrophages: comparison of cells from asthmatics and normal subjects.

Alveolar macrophages (AM) were obtained by bronchoalveolar lavage (BAL) from seven healthy nonallergic, nonasthmatic donors, 15 patients with allergic bronchial asthma, and six patients with aspirin-sensitive asthma. AM were purified by adherence over 2 hr and cultured for an additional 24 hr. Functional assessment of viable cells was carried out for zymosan phagocytosis and for prostaglandin (PG) E2-PGF2 alpha and thromboxane (Tx) B2 release by resting and zymosan-stimulated AM. The eosinophil count in BAL fluid from allergic asthmatics was higher than that from control subjects (3.9% +/- 1.6% vs 0.4% +/- 0.3%, p less than 0.05) and still greater in BAL from patients with aspirin-sensitive asthma (21.7% +/- 9.0%, p less than 0.01). After the 24 hr of incubation, the AM viability was inversely correlated to the percentage of eosinophils in BAL fluid (r = -0.54, n = 21, p less than 0.02). Zymosan phagocytosis was significantly lower by viable cells from both allergic asthmatics and aspirin-sensitive patients as compared with cells from normal donors (p less than 0.05). Zymosan phagocytosis induced a twofold to threefold increase in the release of PGE2, PGF2 alpha, and TxB2 from AM of normal subjects (p less than 0.01) but only a onefold to twofold increase from AM of allergic asthmatic patients. The stimulated AM from aspirin-sensitive patients released smaller quantities of each product than AM from normal subjects or allergic asthmatic patients (p less than 0.05). We conclude that the viability and functional activity of AM are impaired in asthmatic patients and that these deficits correlate with the percent eosinophilia in the BAL; it is therefore suggested that they may be due to an interaction between eosinophils and AM in the bronchoalveolar lumen.

Asthma↗

PubMed1982

Mononuclear phagocytes, prostanoids and rheumatoid arthritis.

We describe a new, simple procedure for obtaining and studying mononuclear phagocytes from inflammatory synovial fluid. The viability and functional characteristics of these macrophages have been carefully checked. This technique has been used to evaluate the macrophagic synthesis of prostaglandins in 16 patients with evolutive rheumatoid arthritis. Significant amounts of prostaglandins, mainly PGE2 and TxB2, are released and increased after zymosan administration. The three tested prostaglandins (PGE2, PGF2 alpha and TxB2) responded in a similar manner. The in vitro PG biosynthesis and the number of harvested adherent cells are negatively correlated with the synovial fluid volume but positively correlated with the disease activity. In fact, we found an heterogeneity among the analyzed macrophages; these can be divided into two populations with marked differences in their PG biosynthesis. The one with the highest synthesis corresponded to the more severe disease.

Arthritis, Rheumatoid↗

PubMed1982

[Mononucleated phagocytes from rheumatoid synovial fluid. Synthesis of prostanoids and first pharmacological applications].

An original and easily reproducible technique for isolating and culturating mononucleated phagocytes from rheumatoid synovial fluid was used by the authors to study the synthesis of PGE2, PGF alpha 2 and TxB2 by macrophages taken from 16 patients with rheumatoid arthritis. The functional importance of these macrophages was evaluated by comparing their ratios of prostaglandin synthesis. PGE2 and TxB2 are released in large quantities and are increased after stimulation with zymosan. Two distinct cell populations having different biochemical characteristics were identified from these macrophages based on their capacity to synthesize prostaglandins. Prostaglandin synthesis was correlated with the clinical progression of rheumatoid arthritic disease as evaluated by Lee's index and the time required to loosen up morning joint stiffness in these patients. No correlation was found between prostaglandin synthesis and the quantity of synovial fluid in the affected joint. The first results of a pharmacological study evaluating the activity of non steroid anti-inflammatory drugs using this experimental model are presented here. The addition of indomethacin to culture medium produces dose-dependent inhibition of prostaglandin synthesis.

Adult↗

PubMed1981

[Alveolar macrophages in asthmatic patients: study of their phagocytic function].

Alveolar macrophages (AM) form the first line of defense against aggression in the lungs. The goal of the present study was to evaluate AM phagocytic function in two types of asthmatic patients: allergic asthma (14 patients) and asthma following ingestion of aspirin (6 patients). Macrophages obtained from bronchiolo-alveolar washings were isolated as a result of their adherence to glass and cultured for 24 hours. The results show that AM viability and phagocytosis of zymosan are reduced in the asthmatic patient. Decreased viability in patients sensitive to aspirin may be the result of alveolar eosinophilia, a quasiconstant finding in asthmatics. Although impaired phagocytosis of zymosan may be explained by the presence of surface IgE on AM of the allergic asthma patient, this is not the case for the aspirin sensitive patient.

Asthma↗

PubMed1980

[Effect of androgens on the growth of skin fibroblasts in culture].

The effect of DHT on skin fibroblasts proliferation was investigated by measurements of DNA concentrations and of 3H-thymidine incorporation variations. 1 nM DHT did not stimulate fibroblasts growth in either genital nor non genital skin fibroblasts. At higher concentrations, DHT inhibited cell proliferation. It can be concluded that in cell culture, fibroblasts growth is not dependent from androgen receptor content.

Adult↗

PubMed1980

[Technic for isolation and culture of macrophages from human synovial fluid].

Macrophages from synovial fluid were obtained by joint puncture of patients with rheumatoid arthritis or non-rheumatoid exudative arthropathies. This fluid was subsequently centrifuged and the resulting cell pellet was recovered and distributed for in vitro culture (Falcon Petri dishes: 60 x 15 or 35 x 10). Cells were washed after 4 hours in culture to eliminate non-macrophagic cells. A second cell wash was effected 24 hours later to eliminate non-adherent cells. The culture medium employed was fetal calf serum MMP 119 (Gibco). The macrophagic nature of the cultured cells was ascertained by non specific esterase determinations (Burstone method) and estimation of the phagocytic index (using zymosan). This technique permits the conservation of viable monocytes in culture thus facilitating investigation of their metabolic activity (for example: prostaglandins, prostanoids or fatty acids) and the effects of anti-inflammatory agents.

Arthritis, Rheumatoid↗

PubMed1978