Airway mucus hyperconcentration in non–cystic fibrosis bronchiectasis

Rationale: Non–cystic fibrosis bronchiectasis is characterized by airway mucus accumulation and sputum production, but the role of mucus concentration in the pathogenesis of these abnormalities has not been characterized. Objectives: This study was designed to: 1) measure mucus concentration and biophysical properties of bronchiectasis mucus; 2) identify the secreted mucins contained in bronchiectasis mucus; 3) relate mucus properties to airway epithelial mucin RNA/protein expression; and 4) explore relationships between mucus hyperconcentration and disease severity. Methods: Sputum samples were collected from subjects with bronchiectasis, with and without chronic erythromycin administration, and healthy control subjects. Sputum percent solid concentrations, total and individual mucin concentrations, osmotic pressures, rheological properties, and inflammatory mediators were measured. Intracellular mucins were measured in endobronchial biopsies by immunohistochemistry and gene expression. MUC5B (mucin 5B) polymorphisms were identified by quantitative PCR. In a replication bronchiectasis cohort, spontaneously expectorated and hypertonic saline-induced sputa were collected, and mucus/mucin concentrations were measured. Measurements and Main Results: Bronchiectasis sputum exhibited increased percent solids, total and individual (MUC5B and MUC5AC) mucin concentrations, osmotic pressure, and elastic and viscous moduli compared with healthy sputum. Within subjects with bronchiectasis, sputum percent solids correlated inversely with FEV1 and positively with bronchiectasis extent, as measured by high-resolution computed tomography, and inflammatory mediators. No difference was detected in MUC5B rs35705950 SNP allele frequency between bronchiectasis and healthy individuals. Hypertonic saline inhalation acutely reduced non–cystic fibrosis bronchiectasis mucus concentration by 5%. Conclusions: Hyperconcentrated airway mucus is characteristic of subjects with bronchiectasis, likely contributes to disease pathophysiology, and may be a target for pharmacotherapy

Mating-associated peak in plasma testosterone concentration in wild male grey-headed flying foxes (Pteropus poliocephalus)

Plasma testosterone (T) concentrations, measured in wild bats of P. poliocephalus in Queensland in 1983-87, showed a peak during the mating season in March. Plasma androstenedione (A) concentrations changed less dramatically with season. Mean testicular concentration and total content of T and A was substantially greater in March than in regressed testes in July-October. Paired adrenal glands were heavier during February to April than during September to November. In the same wild population, throughout a single breeding season (1987), plasma T concentrations were significantly higher in mid-March than 3 weeks previously or 3 weeks later. Testicular T content rose as the breeding season progressed, being greatest during March, coinciding with the large rise in plasma T concentrations. Testicular T concentration and content were correlated significantly with plasma T concentrations. Adrenal glands contained T, but the absolute concentrations were much lower than in the testis. No significant changes in plasma, testicular or adrenal A concentrations were found as the breeding season progressed. The large increase in plasma T during the mating season appears to be due to increased testicular production

Effects of photoperiod on the reproductive physiology of male flying foxes, pteropus poliocephalus

Melatonion concentrations were determined in plasma pools obtained from adult male Pteropus poliocephalus (autumn mating season) at four times of the year. Melatonin levels increased within 3 h of sunset and remained elevated for the duration of the scotophase at all times of the year. Two photoperiod manipulation experiments were performed to examine the role of daylength in the regulation of the timing of the breeding season of this species. In Experiment 1, three adult males were transferred from natural short days to 16L:8D for 137 days and then photoperiod was progressively decreased over 120 days to 9L: 15D; this photoperiod was then maintained for 350 days. Testicular volume (TV) peaked during decreasing photoperiod well before the time of maximal size in natural conditions. During the period in extended short photoperiod these bats showed several cycles of TV change with a progressively decreasing interval between cycles. In Experiment 2, nine adult males were exposed to the same shift to 16L:8D as in Experiment 1, but were subsequently split into three groups: 8L:16D, progressive decrease to 8L: 16D and maintenance in 16L:8D. The 8L: 16D and decreasing photoperiod groups showed coincident premature increases in TV, as in Experiment 1, whereas in the 16L: 8D group TV increased at about the same time as in animals in natural photoperiod. Melatonin determination in the different experimental groups showed that duration of secretion was related to the length of the scotophase in all cases. These experiments demonstrate that regulation of the timing of reproduction in males of this species is influenced by changes in daylength

Expression of a polymorphic epithelial mucin antigen defined by the monoclonal antibody BC2 in ovarian carcinoma: Use of the BC2 antibody for the detection of micrometastases

The BC2 monoclonal antibody, which binds to an epitope on the peptide backbone of polymorphic epithelial mucin, was tested immunohistochemically for reactivity with epithelial ovarian carcinoma. This epitope was expressed in 90 of 91 malignant ovarian tumors; in 88% of these, more than 50% of the tumor cells expressed the epitope. In 94% of the positive tumors, the epitope was expressed on the cell membrane; in 56%, cytoplasmic expression was evident; and in 39%, secreted extracellular antigen was detected. Differences were not clearly discenible between dissimilar histotypes with respect to the percentage of cells expressing antigen and antigen localization. Thirteen of 19 benign ovarian cystadenomas also expressed the epitope, but staining was weak and restricted to the luminal surface of the cell membrane. A blind retrospective immunohistochemical analysis of all second-look laparotomy biopsy specimens from 20 patients also was performed. All four patients in whom microscopic disease was detected by standard pathologic assessment had BC2-positive metastases. Of seven patients in whom recurrent disease subsequently developed despite negative pathologic findings, four had biopsy specimens containing BC2 antigen-positive adenocarcinoma-like cells. Of the nine patients with negative results on operation and no recurrence, one had biopsy specimens containing BC2 antigen-positive adenocarcinoma-like cells. Mesothelial cells, although typically negative, expressed the epitope in one biopsy specimen, necessitating caution in the interpretation of positive cells. The BC2 antibody is reactive with most epithelial ovarian carcinomas and appears to be a useful tool for the detection of micrometastases

Heterogeneity in production, secretion and glycosylation of MUC1 epithelial mucin by primary cultures of ovarian carcinoma

The MUC1 mucin produced by many adenocarcinomas has functions that may be of biological significance and is of importance clinically as a serum tumour marker and as a candidate target for immunotherapy. Previous studies of MUC1 production by ovarian cancers have been limited to immunohistochemical studies of tumour specimens and in vitro studies using cell lines. In this study the biosynthesis secretion and glycosylation of MUC1 were studied in primary cultures of tumour cells obtained from 35 patients with stage 3 ovarian cancer. Although 34 of the 35 tumours produced MUC1 in vitro the concentrations of intracellular and secreted MUC1, as measured by an ELISA using core protein-reactive antibodies, varied over a wide range. In addition, the amount of secreted MUC1 as a proportion of the intracellular concentration varied between tumours. Pulse/chase amino acid labelling studies of MUC1 biosynthesis also demonstrated variation in secretion rates. Multivariate regression analysis showed that of the variables tumour size, histological type, grade, ploidy status and intracellular and secreted MUC1 concentrations in vitro, only mucin secretion rate was significantly associated with serum mucin concentrations (p < 0.001). Culture of tumour cells for 4 days in the presence or absence of a competitive inhibitor of O-glycosylation, BAG, showed that the degree of glycosylation of MUC1 varied between tumours and that under-glycosylation was not correlated with production or secretion rates. Our study has shown heterogeneity in the production, secretion and glycosylation of MUC1 and a strong correlation between the secretion rate in vitro and the concentration in the serum of patients. (C) 1995 Wiley-Liss, Inc

Effect of Interferon-γ and TNF-α on MUC1 Mucin Expression in Ovarian Carcinoma Cell Lines

In view of the potential uses of cell surface tumour associated antigens in novel anticancer treatment, a study was designed to investigate whether the biological response modifiers interferon-gamma (IFN-γ) and tumour necrosis factor-alpha (TNF-α) could effect the expression of an epitope on the tumour associated MUC1 epithelial mucin. Four ovarian carcinoma cell lines showing high (OAW42 and GG) and low (JAM and PEO1) basal expression of MUC1 were treated with 10-1000 U/mL of IFN-γ or TNF-α for one or five days. Changes in MUC1 expression in cells exposed to IFN-γ or TNF-α were monitored using an ELISA technique with the monoclonal antibody BC2 which reacts with a core protein epitope on the MUC1 mucin, and then corrected for the number of viable cells present. TNF-α had little effect on MUC1 expression, but one or five days exposure to IFN-γ significantly increased MUC1 expression (p < 0.01) in all cell lines including the two cell lines that initially showed little or no expression

Serum markers CASA and CA 15-3 in ovarian cancer: All MUC1 assays are not the same

The serum MUC1 markers CASA and CA 15-3 were compared with CA 125 in the serum of patients with ovarian cancer and in pregnant women. Used individually, CASA and CA 15-3 gave sensitivities of 54 and 56% in pre-operative ovarian carcinoma (n = 50), though these were lower than with CA 125 (84%). CASA levels were elevated in 3 women with a negative CA 125, while CA 15-3 was elevated in 2 of these women. The combined use of CA 125 with CASA or CA 15-3 led to the preclinical detection of recurrence in 4/5 patients, with mean lead times of 3.6 and 4.3 months, respectively. Of particular interest was the marked difference in reactivity observed with CASA and CA 15-3 in some patients, despite both assays utilising monoclonal antibodies (MAbs) that react with the MUC1 mucin. CA 15-3 and CASA showed a lower than expected correlation in patients with ovarian cancer (r = 0.70), with some patients having high concentrations of one mucin marker and low concentrations of another. Furthermore, different marker profiles were observed when monitoring the progress of patients with these markers. Marked differences between CA 15-3 and CASA were also observed in the serum of pregnant women (n = 10), where CASA showed marked elevation (mean 33.6 times cutpoint) and CA 15-3 did not (mean 0.88 times cutpoint). These data suggest that the specificities of the MAbs used in these assays affect the glycoform of MUC1 detected, and that it should not be assumed that all MUC1 assays will behave in the same manner

Expression of tumour markers CA125, CASA and OSA in minimal/mild endometriosis

Ovarian cancer associated antigens CA125, CASA and OSA were measured in serum from 23 patients with mild endometriosis before, during and after medical therapy. Pretreatment CA125 levels were elevated above 35 mu/ml in 4(17%), and above 25 mu/ml in 7 (30%) patients. Mean CA125 levels decreased during treatment, but in only 10 patients did levels reflect disease response. There was no correlation between CA125 levels and disease severity as measured by modified American Fertility Society Scoring. Neither CASA nor OSA were detected in these women