In situ activation of caspases and serine proteases during apoptosis detected by affinity labeling their enzyme active centers with fluorochrome-tagged inhibitors

Activation of caspases is the key event of apoptosis. To detect this event in situ we applied fluorochrome-labeled inhibitors of caspases (FLICA) as affinity labels of active centers of these enzymes. The FLICA are fluorescein- or sulforhodamine-conjugated peptide-fluoromethyl ketones that covalently, with 1:1 stoichiometry, bind to enzymatic centers of caspases; the specificity is provided by the peptide sequence of amino acids. Similarly, we applied fluorescent inhibitors of serine proteases (FLISP) to detect active sites of the latter enzymes. Exposure of live cells to FLICA of FLISP led to uptake of these ligands and their binding to activated caspases or active sites of serine proteases; the unbound reagents were removed by cell rinse. Only cells undergoing apoptosis were labeled with FLISP or FLICA. Intracellular binding sites of FLICA are consistent with known localization of caspases. Covalent binding of FLICA or FLISP allowed us to identify the labeled proteins by immunoblotting: the proteins that bound individual FLICAs had molecular weight between 17 and 22 kDa, which corresponds to large subunits of the caspases; two proteins reacting with FLISP were about 57 and 60 kDa, which suggests that they are novel enzymes. Detection of caspases or serine proteases activation can be combined with other markers of apoptosis or cell cycle for multiparametric analysis by flow or laser scanning cytometry. Being caspase inhibitors, FLICA arrest the process of apoptosis and prevent cell disintegration. The stathmo-apoptotic assay was developed, therefore, to obtain cumulative apoptotic index over a long period of time and estimate a rate of cell entry into apoptosis for cell populations.

Urokinase plasminogen activator and its inhibitor, PAI-1, as prognostic markers in breast cancer: from pilot to level 1 evidence studies

BACKGROUND

For optimum management of patients with cancer, accurate assessment of prognosis is essential. The primary determinant of outcome in malignancy is the formation of distant metastases. Urokinase plasminogen activator (uPA) is a serine protease causally involved in invasion and metastasis.

CONTENT

Data from model systems show that uPA is unequivocally involved in cancer dissemination. Consistent with its role in metastasis, multiple independent groups have shown that high uPA concentrations in primary breast cancers correlate with poor prognosis. For determining outcome, the prognostic impact of uPA was both independent of traditionally used factors and prognostic in patients with axillary node-negative disease. Paradoxically, high concentrations of plasminogen activator inhibitor (PAI-1), an endogenous inhibitor of uPA, also correlate with poor prognosis in patients with breast cancer, including the subgroup with node-negative disease. The prognostic value of uPA/PAI-1 in axillary node-negative breast cancer patients was recently confirmed in both a prospective randomized trial and a pooled analysis, i.e., two different level 1 evidence (LOE-1) studies.

CONCLUSIONS

uPA and PAI-1 are among the first biological prognostic factors to have their clinical value validated using LOE-1 evidence studies. Determination of these analytes may help identify low-risk node-negative breast cancer patients for whom adjuvant chemotherapy is unnecessary.

[Determination of purity of different types of aprotinin by micellar electrokinetic capillary chromatography]

A sensitive and rapid method was developed for purity determination of different types of aprotinin by micellar electrokinetic capillary chromatography (MECC). MECC was performed with 80 mmol/L Na2HPO4-H3PO4(pH 7.00) buffer solution containing 4 mmol/L cetyltrimethyl ammonium bromide (CTAB) at an applied voltage of 15 kV. The electrophoresis was monitored at 277 nm, and completed in 6 minutes. The relative standard deviations of migration time and area for aprotinin were below 0.3% and below 5% respectively within 1 day (for 6 repetitive runs). The effect of high concentration of salt in the samples has been studied. The results obtained by capillary zone electrophoresis, MECC and high performance liquid chromatography were compared, and those of MECC were the best.

Prognostic value of the urokinase-type plasminogen activator, and its inhibitors and receptor in breast cancer patients

Urokinase-type plasminogen activator (uPA), its inhibitors (PAI-1 and PAI-2), and its receptor (uPAR) play a key role in tumor invasion and metastasis. This study was designed to evaluate the prognostic impact of uPA, PAI-1, PAI-2, and uPAR and the combination of these factors in a group of 460 primary breast cancer patients. Concentrations of all 4 components of the uPA system were measured in tumor extracts using enzyme-linked immunosorbent assays (American Diagnostica, Inc, Greenwich, CT). After a median follow-up of 33 months, 18.5% of the patients had relapsed. The Cox proportional hazards model was applied for both univariate and multivariate analyses of disease-free survival (DFS). PAI-1 and PAI-2 were shown to provide independent prognostic information in breast cancer. Patients with either low levels of PAI-1 or high levels of PAI-2 were found to have better DFS (relative risk was 2.08 and 1.78, respectively). The prognostic value could be even further improved by a combination of both inhibitors. Aside from the uPA inhibitors, only nodal status and hormonal receptor status retained independent prognostic value. The other 2 invasion markers, uPA and uPAR, showed no statistically significant impact on DFS. In our patients, who were mostly treated with adjuvant therapy, uPA was not found to be an independent prognostic marker for DFS; this could be a consequence of the predictive value of uPA for response to adjuvant therapy and should be further investigated.

Inhibitory function of secretory leukocyte proteinase inhibitor (SLPI) in human saliva is HIV-1 specific and varies with virus tropism

OBJECTIVE

Secretory leukocyte proteinase inhibitor (SLPI) is an endogenous mucosa associated protein that has been proposed to possess anti-human immunodeficiency virus type 1 (HIV-1) activity. The aim of this study was to investigate the biological function of SLPI in salivary mediated inhibition of HIV infection and in addition the inhibitory effect of SLPI using isolates of varied virus tropism.

MATERIAL AND METHODS

The inhibitory effect of HIV-1 infection in vitro, mediated by 60 different saliva samples was analyzed with respect to levels of SLPI. Salivary samples depleted from IgA and SLPI, respectively, were further analyzed for anti-HIV activity. The antiviral effect of recombinant SLPI was investigated within an in vitro system of HIV-1 infection of target cells using a panel of viral isolates with distinct coreceptor usage. Furthermore we tested a panel of overlapping synthetic peptides, representing the amino acids in SLPI, for their capacity to inhibit HIV-1 infection of human peripheral blood mononuclear cells (PBMCs).

RESULTS AND CONCLUSIONS

These experiments show that elevated levels of salivary SLPI can be associated with an increased inhibitory effect of the whole saliva sample, and that this inhibitory effect is decreased with broad coreceptor usage of the virus.

Plasminogen activating capacity in gingival fluid from deteriorating and stable periodontal pockets

The plasminogen activating system plays an important role in tissue proteolysis in physiological as well as pathological processes. Earlier studies have shown high concentrations of the plasminogen activator t-PA as well as its inhibitor PAI-2 in gingival crevicular fluid (GCF). In addition, gingival inflammatory reactions have been related to increases in t-PA and PAI-2. In order to explore the potential role of the plasminogen activating system for the development of destructive periodontal disease, the aim of this study was to assess the balance of the activator t-PA to the inhibitor PAI-2 in GCF from patients, clinically defined to represent different periodontal conditions. The Progression Group consisted of 12 periodontitis patients with 1 or more sites having shown an increased pocket depth of > or = 3 mm during the last 2 years of maintenance care and with > or = 8 unchanged or improving sites during the period. The Non Progression Group consisted of patients who had shown a decreased or unchanged pocket depth of all sites during the last 3 years of maintenance care. Sampling of GCF was done with small disks of Millipore-filter, and t-PA and PAI-2 were analyzed with ELISAs. There was no difference in the t-PA/PAI-2 ratio between the two groups. However, an intra-individual comparison within the Progression Group showed a higher ratio at the deteriorating sites than at the stable sites. Even though no difference was found between the groups, the higher t-PA/PAI-2 ratio at the deteriorating sites in the Progression Group suggests an involvement of the plasminogen activating system in the proteolytic events leading to breakdown of the tooth supporting tissues.

Increased concentration of fecal α1 -antitrypsin is associated with cow's milk allergy in infants with atopic eczema

BACKGROUND

The use of fecal alpha1-antitrypsin in the monitoring of intestinal inflammation in infants with atopic eczema and food allergy was evaluated.

METHODS

The study material comprised 26 atopic infants with confirmed food allergy. Fecal samples were collected before an elimination diet and 3 months later for the determination of alpha1-antitrypsin.

RESULTS

Nine (35%) of the 26 patients demonstrated an increased fecal concentration of alpha1-antitrypsin (median 3 mg/g; range 2.8-6.4 mg/g). In all nine patients (100%) the oral cow's milk challenge was positive as opposed to only six (35%) in those with normal alpha1-antitrypsin concentration (P = 0.0024). No further connections between alpha1-antitrypsin and other food allergies were detected. As a result of an adequate elimination diet, the fecal concentration of alpha1-antitrypsin was normalized in seven patients, with a favourable clinical response in atopic eczema in six and no improvement in one patient.

CONCLUSIONS

Our results indicate that serial determinations of fecal alpha1-antitrypsin provide a useful non-invasive tool for the detection and follow-up of intestinal inflammation in a certain group of atopic infants with cow's milk allergy and severe inflammation of the gut.

[Plasminogen activators of urokinase and tissue types and their inhibitor (PAI-1) in cytosol fraction in thyroid diseases]

Enzyme immunoassay (ELISA) was used to estimate the levels of plasminogen activators of urokinase (uPA) and tissue (tPA) types and one of their inhibitors (PAI-I) in the cytosolic fraction of the thyroid in 129 patients with malignant and benign tumors and various non-cancer diseases of the gland. Tumors from patients with thyroid cancer displayed the lowest levels of tPA and the highest levels of uPA and PAI-I, while those from patients with benign thyroid diseases, including adenoma, had high concentrations of tPA and relatively low levels of uPA and PAI-I in the tissue of the diseased organ. At the same time, the lowest levels of uPA and PAI-I were found in patients suffering from toxic goiter with and without adenomatosis. In terms of uPA and PAI-I levels, patients with nodular colloidal goiter were intermediate between those with toxic goiter and adenoma, on the one hand, and those with thyroid cancer, on the other.

Development of an assay for label-free high-throughput screening of thrombin inhibitors by use of reflectometric interference spectroscopy

We describe the development of, and analytical conditions used for, parallel affinity assay for thrombin inhibitors adapted to the first label-free optical screening HTS detection set-up fully integrable into a screening platform. To achieve compatibility with pharmaceutical libraries, an HTS-transducer was realized by gluing the bottomless scaffolds of 96- and 384-well plastic microplates on to transducer slides. The transducer are coated with a dextran, to ensure biocompatibility and functionality, and a known thrombin inhibitor was attached covalently to it. By adapting reflectometric interference spectroscopy for simultaneous reading of the whole transducer plate we were able to detect the binding of thrombin in all the wells of the microplates on-line, in parallel, and time resolved. By using an inhibition assay, the screening of 384 substances for thrombin activity can be performed within an assay time of less than 15 min. We also show that the data quality is high enough for parallel quantification of the IC 50 values of the library substances.

Decline in the expression of the serine proteinase inhibitor maspin is associated with tumour progression in ductal carcinomas of the breast

Maspin is an inhibitor of serine proteinases with tumour suppressor activity. Its expression appears to be reduced in advanced stages of breast cancer. A large series of archival breast tissue specimens has been examined, including normal glands (n=7), fibrocystic change (n=22), ductal carcinoma in situ (DCIS, n=12), infiltrating carcinomas (n=128) and their lymph node metastases (n=65), using a specific monoclonal antibody. Myoepithelium invariably showed strong maspin expression. In epithelial cells, the strongest expression was found in normal breast and fibrocystic change. A significant stepwise decrease in maspin expression (p<0.0001) occurred in the sequence DCIS - invasive cancer - lymph node metastasis. However, a subset of infiltrating carcinomas showed strong maspin expression, significantly associated with a lower rate of lymph node metastasis at the time of diagnosis (p<0.01). This was independent of tumour size and grade. The in vivo observations presented here are in keeping with data obtained in prior in vitro experiments. Maspin emerges as an indicator of tumour progression and metastatic potential, and might be exploited to predict breast cancer prognosis. According to in vitro data, its tumour suppressor activity is likely to involve both the modulation of cell motility/invasiveness and the inhibition of angiogenesis.

Identification of a serine protease inhibitor homologue in Bird's Nest by an integrated proteomics approach

For centuries, the edible nests of Collocalia spp. ("Bird's Nests") have been used as a Chinese delicacy that had been claimed to be an effective health-giving tonic. However, clinical studies indicated that in Singapore, Bird's Nest is the most common cause of food-induced anaphylaxis in children, which could lead to potentially life-threatening allergenic reactions. The purpose of this study was to characterize the major allergens in Bird's Nest by using the combined technologies of two-dimensional gel electrophoresis (2-DE), immunochemistry, N-terminal protein sequencing, and mass spectrometry. Results from the immunostaining of the Western blots of the Bird's Nest 2-DE separated proteins with the sera from allergic patients indicated the presence of a major allergen of 66 kDa. Initial searches of the matrix assisted laser desorption/ionization--time of flight--mass spectrometry (MALDI-TOF-MS) tryptic peptide masses of the allergen in the SWISS-PROT and NCBI nonredundant databases revealed that this protein was novel. Based on the partial protein sequence information obtained from N-terminal microsequencing and nanoelectrospray-tandem MS, the 66 kDa immunoreactive allergen was found to be homologous to ovoinhibitor, a Kazal-type serine protease inhibitor, which is one of the dominant allergens found in chicken egg white.

The trimannosyl cores of N-glycans are important for the procoagulant protease-inhibitory activity of urinary protein C inhibitor

We investigated the relationship between the procoagulant protease-inhibitory activity and the N-glycan structures in urinary protein C inhibitor (uPCI) by sequential exoglycosidase digestions based on the N-glycan structures elucidated in this report. uPCI was glycosylated on the three potential N-glycosylation sites, asparagines 230, 243 and 319 (N230, N243 and N319) in the molecule and had four biantennary complex type sugar chains. The inhibitory activities of uPCI toward thrombin and plasma kallikrein were little changed by the sequential removal of N-acetylneuraminic acid and galactose residues from the termini and N-acetylglucosamine residues from the branches of the N-glycans. However, the inhibitory activities were markedly decreased by further removing alpha-mannose residues from the trimannosyl cores of the N-glycans. These results suggest that the trimannosyl cores of N-glycans are important for uPCI to inhibit the procoagulant protease.

The expression of plasminogen activator system in a rat model of periodontal wound healing

BACKGROUND

The plasminogen activator system has been proposed to play a role in proteolytic degradation of extracellular matrices in tissue remodeling, including wound healing. The aim of this study was to elucidate the presence of components of the plasminogen activator system during different stages of periodontal wound healing.

METHODS

Periodontal wounds were created around the molars of adult rats and healing was followed for 28 days. Immunohistochemical analyses of the healing tissues and an analysis of the periodontal wound healing fluid by ELISA were carried out for the detection of tissue-type plasminogen activator (t-PA), urokinase-type plasminogen activator (u-PA), and 2 plasminogen activator inhibitors (PAI-1 and PAI-2).

RESULTS

During the early stages (days 1 to 3) of periodontal wound healing, PAI-1 and PAI-2 were found to be closely associated with the deposition of a fibrin clot in the gingival sulcus. These components were strongly associated with the infiltrating inflammatory cells around the fibrin clot. During days 3 to 7, u-PA, PAI-1, and PAI-2 were associated with cells (particularly monocytes/macrophages, fibroblasts, and endothelial cells) in the newly formed granulation tissue. During days 7 to 14, a new attachment apparatus was formed during which PAI-1, PAI-2, and u-PA were localized in both periodontal ligament fibroblasts (PDL) and epithelial cells at sites where these cells were attaching to the root surface. In the periodontal wound healing fluid, the concentration for t-PA increased and peaked during the first week. PAI-2 had a similar expression to t-PA, but at a lower level over the entire wound-healing period.

CONCLUSIONS

These findings indicate that the plasminogen activator system is involved in the entire process of periodontal wound healing, in particular with the formation of fibrin matrix on the root surface and its replacement by granulation tissue, as well as the subsequent formation of the attachment of soft tissue to the root surface during the later stages of wound repair.

Use of a fixed activated partial thromboplastin time ratio to establish a therapeutic range for unfractionated heparin

BACKGROUND

The commonly recommended therapeutic range for patients receiving unfractionated heparin of 1.5 to 2.5 times the control activated partial thromboplastin time (aPTT) is not universally applicable. It has been suggested that the therapeutic range for each aPTT reagent should be based on plasma heparin levels. We sought to identify an aPTT ratio that corresponds to therapeutic anti--factor Xa heparin levels for combinations of several reagents and coagulometers that are commonly used.

METHODS

Citrated plasma was collected from 126 unselected patients receiving unfractionated heparin. Four automated coagulometers and 6 commercial aPTT reagents were used to measure the aPTT. Plasma anti--factor Xa levels were measured by means of a commercially available assay. The relationship between the aPTT results and anti-factor Xa heparin levels for each reagent-coagulometer combination was determined by linear regression analysis, and the aPTT results corresponding to therapeutic anti--factor Xa heparin levels were calculated.

RESULTS

For all reagent-coagulometer combinations studied, an aPTT ratio of 1.5 resulted in anti--factor Xa heparin levels considerably below the lower limit of the therapeutic range. When the aPTT was performed on any of the coagulometers assessed with the use of Actin (Dade Diagnostics, Aguada, Puerto Rico) and IL Test (Instrumentation Laboratories, Fisher Scientific, Unionville, Ontario) reagents, aPTT ratios necessary to achieve therapeutic anti--factor Xa heparin levels approximated 2.0 to 3.5.

CONCLUSION

For laboratories that cannot perform heparin levels, the use of less responsive reagents and any of the coagulometers studied, along with target aPTT ratio between 2.0 and 3.5, appears to be a reasonable alternative.

Alpha-1-antichymotrypsin and oxidative stress in the peripheral blood from patients with probable Alzheimer disease: a short-term longitudinal study

To evaluate the stability and reproducibility of selected peripheral oxidative stress markers and their possible relation to cognitive performance, three different blood samples were taken at 7- to 10-day intervals from 11 patients with probable Alzheimer disease (AD) and 11 nondemented controls. Blood samples were also collected once from 6 patients with vascular dementia (VD). Alpha-1-antichymotrypsin (ACT), C-reactive protein (CRP), glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), lactoferrin (LTF), and total lipid peroxidation (LPO) were then measured. Blood levels of ACT and GSH-Px were increased in AD patients but not in patients with VD. Levels of LTF, CRP, and LPO were comparable between AD patients and controls. Erythrocyte SOD activity was increased in AD patients. Blood levels of ACT negatively correlated with LPO levels and positively correlated with scores of the Global Deterioration Scale of AD patients. ACT might be implicated in controlling oxidative damage of blood lipids and their turnover during the progression of AD.

Molecular forms of prostate-specific antigen and human kallikrein 2 as promising tools for early diagnosis of prostate cancer

Prostate-specific antigen (PSA) is the most useful marker in the early detection of prostate cancer and for the monitoring of patients with this diagnosis. Molecular forms of PSA and also human kallikrein 2 have been used to discriminate between benign prostatic hyperplasia and prostate cancer as well as for the detection of prostate cancer within the gray zone of PSA. In this respect, a literature survey on the diagnostic validity of free PSA (fPSA) related to total PSA (tPSA), PSA bound to alpha1-antichymotrypsin (ACT-PSA), and complexed PSA is given together with our results. The ratio of fPSA:tPSA has been shown to improve the specificity of prostate cancer diagnosis on the basis of tPSA measurements. Unnecessary biopsies can be reduced by about 19-64% in the total PSA range of 4-10 microg/liter while only missing 5-10% of cancers. Furthermore, carcinomas in patients with PSA values <4 microg/liter can be detected, indicating an improved sensitivity because of the percent fPSA at low PSA values. ACT-PSA or complexed PSA alone and the calculated derivatives are not superior in their discriminatory power compared with the percent fPSA. The diagnostic significance of the other molecular PSA forms and human kallikrein 2 needs to be evaluated in more extensive clinical trials.

Increased secretory leukoprotease inhibitor in patients with nonsmall cell lung carcinoma

BACKGROUND

It is well known that acute pulmonary inflammation, such as that observed in pneumonia, elevates secretory leukoprotease inhibitor (SLPI) levels in serum. A previous report indicated that serum SLPI levels in lung carcinoma patients with concurrent pneumonia were significantly higher than in those in patients whose disease was unaccompanied by pneumonia or in healthy subjects. The authors hypothesized that serum SLPI may increase in patients with lung carcinoma, even carcinoma occurring without pneumonia, and that cells in lung carcinoma might produce SLPI.

METHODS

Serum SLPI levels in 58 patients with primary lung carcinoma unaccompanied by pneumonia and in 42 healthy subjects were measured by an enzyme immunoassay. Twenty-four specimens from 24 of the patients with primary lung carcinoma also were examined immunohistochemically using the rabbit antihuman SLPI antibody.

RESULTS

The results of the current study confirmed that the serum levels of SLPI in patients with primary lung carcinoma were higher than those in healthy subjects, and further found there was no significant correlation between serum SLPI levels and C-reactive protein in lung carcinoma patients without pneumonia. When classifying primary lung carcinoma by its histology, SLPI levels in patients with adenocarcinoma and squamous cell carcinoma were significantly higher than in those in patients with small cell lung carcinoma (SCLC). In patients with nonsmall cell lung carcinoma (NSCLC), the SLPI levels in the advanced group (International Union Against Cancer Stages III and IV disease; n = 35) were significantly elevated compared with the nonadvanced group (Stages I and II disease; n = 12), and such elevated SLPI levels were reduced in some cases by an efficient response to surgical therapy or chemotherapy. Immunohistochemical studies showed that all the NSCLC tissues were stained with anti-human SLPI antibody, whereas staining was not noted in any of the SCLC tissues.

CONCLUSIONS

The authors believe that the findings of the current study demonstrate that cells of NSCLC produce SLPI. Furthermore, they suggest that serum SLPI levels in serum may be a helpful marker in patients with NSCLC unaccompanied by pneumonia, and that SLPI also could be used as an immunohistochemical marker to distinguish between NSCLC and SCLC.

Increased concentrations of secretory leukocyte protease inhibitor in peritoneal fluid of women with endometriosis

Secretory leukocyte protease inhibitor (SLPI) is a potent inhibitor of human leukocyte elastase. We investigated whether SLPI was present in the peritoneal fluid of women with endometriosis and to clarify the role of SLPI in the pathogenesis of endometriosis. Western blot analyses revealed that SLPI protein was detected as a 12 kDa band in peritoneal fluid. The peritoneal fluid concentrations of SLPI, elastase and interleukin-6 were assayed by enzyme-linked immunosorbent assays (ELISA). SLPI concentrations and the SLPI/elastase ratio in the peritoneal fluid of women with endometriosis were higher than in samples from women without endometriosis. There was no significant correlation between concentrations of SLPI and interleukin-6 in the peritoneal fluid. Immunohistochemistry using an anti-SLPI polyclonal antibody revealed positive staining in peritoneal macrophages, but not lymphocytes. The present findings suggest that SLPI found in the peritoneal fluid of patients with endometriosis may contribute to the pathogenesis of endometriosis.

Immunolocalisation of BPTI-like serine proteinase inhibitory proteins in mast cells, chondrocytes and intervertebral disc fibrochondrocytes of ovine and bovine connective tissues. An immunohistochemical and biochemical study

A polyclonal anti-bovine pancreatic trypsin inhibitor (BPTI) IgY was raised in chickens immunised with aprotinin. The anti-BPTI IgY was subsequently isolated from egg yolks and purified to homogeneity by affinity chromatography on immobilised aprotinin and by Superose 6 size exclusion fast protein liquid chromatography (FPLC). Immunoblotting with the chicken IgY demonstrated its specificity for BPTI; 3.9 ng BPTI could be detected by this technique. There was no crossreactivity against alpha1-proteinase inhibitor (human and sheep), inter-alpha-trypsin inhibitor (human and sheep), secretory leucocyte proteinase inhibitor or a range of serine proteinase inhibitory proteins (SPIs) isolated from plant sources (soybean and lima bean trypsin inhibitor, potato trypsin and chymotrypsin inhibitors) or serum SPIs (antithrombin-III, alpha2-macroglobulin). Immunoblotting using the anti-BPTI IgY identified the 6- to 12- and 58-kDa forms of endogenous ovine cartilage SPIs in cartilage extracts, confirming the interrelationship of the ovine cartilage SPIs with BPTI. BPTI-domain SPIs were immunolocalised within mast cells of ovine and bovine duodenum, lung and pancreas, and in ovine and bovine bronchial cartilage chondrocytes, chondrocytes of the superficial and intermediate zones of articular cartilage and in the fibrochondrocytes/chondrocytes of the nucleus

Elastosis in lung carcinoma: immunohistochemical, ultrastructural and clinical studies

Elastosis is the pathological finding of focal deposits of elastic fibers in abnormal amounts within tissue. It is well described in the case of infiltrating carcinoma of the breast, but elastosis in lung carcinoma has not been previously documented in detail. We investigated the characteristics of elastosis in lung carcinoma with light and electron microscopies, and immunohistochemistry for alpha-1-antitrypsin. A total of 184 surgically resected primary lung carcinomas were studied. Elastosis was detected in adenocarcinomas (85/106), squamous cell carcinomas (11/60) and adenosquamous carcinomas (5/7), but not in small-cell carcinomas (n = 4) or large-cell carcinomas (n = 5). The degree of elastosis in each case was divided into one of five grades, graded as 3+ to 1-. The score of elastosis was significantly higher in adenocarcinoma than that in squamous-cell carcinoma (P<0.01). In the cases of adenocarcinoma, the mean score of elastosis in the well-differentiated type (WD n = 43) was higher than that in the moderately differentiated (MD) (n = 39; P = 0.012) and poorly differentiated (PD) types (n = 24; P<0.01). The mean score of elastosis in MD adenocarcinoma was also higher than that in the PD type (P<0.01). Light- and electron-microscopic analyses revealed that these elastic fibers in elastosis were composed of aggregates of thick mature and fine immature elastic fibers, and were positive for alpha-1-antitrypsin. It is suggested that both degraded elastic fibers and newly synthesized fibers are contained in the elastosis of lung carcinoma. Although no significant evidence was detected to suggest any correlation between elastosis and the degree of tumor invasion, the survival curves of adenocarcinomas with elastosis showed a significantly improved prognosis than of those without elastosis in the cases of stages IA and IB (n = 52; P = 0.026).

Localization of porcine trappin-2 (SKALP/elafin) in trachea and large intestine by in situ hybridization and immunohistochemistry

Trappin-2 (SKALP/elafin), an elastase inhibitor, belongs to a unique family of proteinase inhibitors that are covalently anchored at the site of action through their transglutaminase substrate domain and are collectively called trappins. The transglutaminase substrate domain is therefore called "cementoin moiety". Currently, human, porcine, and bovine trappin-2 (SKALP/elafin) have been characterized. Previously, we showed that porcine trappin-2 (SKALP/elafin) occurs mainly in the trachea and large intestine. To determine the localization of trappin-2 (SKALP/elafin) at the cellular level, we carried out in situ hybridization and immunohistochemistry using the porcine trachea and large intestine and found that trappin-2 (SKALP/elafin) is produced in the goblet cells of the tracheal epithelium and of the large intestinal crypts. These locations suggest that trappin-2 (SKALP/elafin) is secreted onto the luminal surface of the trachea and crypts of Lieberkuhn and plays a protective role against destructive bacterial proteinases.

Peptide exosite inhibitors of factor VIIa as anticoagulants

Potent anticoagulants have been derived by targeting the tissue factor-factor VIIa complex with naive peptide libraries displayed on M13 phage. The peptides specifically block the activation of factor X with a median inhibitory concentration of 1 nM and selectively inhibit tissue-factor-dependent clotting. The peptides do not bind to the active site of factor VIIa; rather, they work by binding to an exosite on the factor VIIa protease domain, and non-competitively inhibit activation of factor X and amidolytic activity. One such peptide (E-76) has a well defined structure in solution determined by NMR spectroscopy that is similar to the X-ray crystal structure when complexed with factor VIIa. These structural and functional studies indicate an allosteric 'switch' mechanism of inhibition involving an activation loop of factor VIIa and represent a new framework for developing inhibitors of serine proteases.

Immunoelectronmicroscopic imaging of spermadhesin AWN epitopes on boar spermatozoa bound in vivo to the zona pellucida

Spermadhesin AWN is a major protein of boar seminal plasma and a sperm surface-associated lectin. AWN binds to beta-galactosides and to porcine zona pellucida glycoproteins, suggesting a role for this protein in primary gamete interaction. However, because capacitation induces remodelling of the sperm surface and AWN is peripherally bound to the plasma membrane, the present study sought to investigate whether AWN is present or absent in the subpopulation of spermatozoa that reaches the ovulated oocyte at the period of fertilization in vivo. Therefore, tubal tissues and oocytes from sows mated with a fertile boar were collected 6-8 h after ovulation. Tissues and oocyte sperm complexes were fixed, immunolabelled with anti-AWN monoclonal antibodies, and examined by means of light and scanning electron microscopy. The results show that spermadhesin AWN is present in spermatozoa seen along the genital tract of the natural mated sow as well as on plasmalemmal remnants of spermatozoa bound to the zona pellucida in vivo.

Evidence for excessive bronchial inflammation during an acute exacerbation of chronic obstructive pulmonary disease in patients with alpha(1)-antitrypsin deficiency (PiZ)

Patients with homozygous (PiZ) alpha(1)-antitrypsin (AAT) deficiency have not only low baseline serum AAT levels (approximately 10 to 15% normal) but also an attenuated acute phase response. They are susceptible to the development of premature emphysema but may also be particularly susceptible to lung damage during bacterial exacerbations when there will be a significant neutrophil influx. The purposes of the present study were to assess the inflammatory nature of acute bacterial exacerbations of chronic obstructive pulmonary disease (COPD) in subjects with AAT deficiency, to compare this with COPD patients without deficiency, and to monitor the inflammatory process and its resolution following appropriate antibacterial therapy. At the start of the exacerbation, patients with AAT deficiency had lower sputum AAT (p < 0.001) and secretory leukoprotease inhibitor (SLPI; p = 0.02) with higher elastase activity (p = 0.02) compared with COPD patients without deficiency. Both groups had a comparable acute phase response as assessed by C-reactive protein (CRP) but the AAT-deficient patients had a minimal rise in serum AAT (to < 6 microM). After treatment with antibiotics, in patients with AAT deficiency, there were significant changes in many sputum proteins including a rise in SLPI levels, and a reduction in myeloperoxidase (MPO) and elastase activity (p < 0. 005 for all measures); the sputum chemoattractants interleukin-8 (IL-8) and leukotriene B(4) (LTB(4)) fell (p < 0.01), and protein leak (sputum/serum albumin ratio) became lower (p < 0.01). The changes were rapid and within 3 d of the commencement of antibiotic therapy the biochemical markers had decreased significantly, but took a variable time thereafter to return to baseline values. In conclusion, patients with AAT deficiency had evidence of increased elastase activity at the start of the exacerbation when compared with nondeficient COPD patients which probably reflects a deficient antiproteinase screen (lower sputum AAT and SLPI). The increased bronchial inflammation at presentation resolved rapidly with 14 d of antibiotic therapy.