How in vitro maturation changes the proteome of ovine cumulus-oocyte complexes?

The present study evaluated the effects of in vitro maturation (IVM) on the proteome of cumulus-oocyte complexes (COCs) from ewes. Extracted COC proteins were analyzed by LC-MS/MS. Differences in protein abundances (p < 0.05) and functional enrichments in immature versus in vitro-matured COCs were evaluated using bioinformatics tools. There were 2550 proteins identified in the COCs, with 89 and 87 proteins exclusive to immature and mature COCs, respectively. IVM caused downregulation of 84 and upregulation of 34 proteins. Major upregulated proteins in mature COCs were dopey_N domain-containing protein, structural maintenance of chromosomes protein, ubiquitin-like modifier-activating enzyme 2. Main downregulated proteins in mature COCs were immunoglobulin heavy constant mu, inter-alpha-trypsin inhibitor heavy chain 2, alpha-2-macroglobulin. Proteins exclusive to mature COCs and upregulated after IVM related to immune response, complement cascade, vesicle-mediated transport, cell cycle, and extracellular matrix organization. Proteins of immature COCs and downregulated after IVM were linked to metabolic processes, immune response, and complement cascade. KEGG pathways and miRNA-regulated genes attributed to downregulated and mature COC proteins related to complement and coagulation cascades, metabolism, humoral response, and B cell-mediated immunity. Thus, IVM influenced the ovine COC proteome. This knowledge supports the future development of efficient IVM protocols for Ovis aries.

The low density lipoprotein receptor-related protein contributes to selective uptake of high density lipoprotein cholesteryl esters by SW872 liposarcoma cells and primary human adipocytes.

The concept that selective transfer of high density lipoprotein (HDL)-derived cholesteryl esters (CE) does not require lipoprotein internalization has been challenged recently by evidence that implicates HDL recycling during the selective uptake process. This has prompted us to examine the role of the low density lipoprotein receptor-related protein (LRP) in selective uptake. LRP is an endocytic receptor for lipoprotein lipase (LpL) and apolipoprotein E (apoE) ligands that are able to mediate selective uptake. We report that molecules that interfere with ligand binding to LRP, such as the receptor-associated protein (RAP), suramin, alpha(2)-macroglobulin, or lactoferrin, inhibit HDL-CE selective uptake by human primary adipocytes and SW872 liposarcoma cells by 35-50%. This partial inhibition of selective uptake from total HDL was not due to preferential inhibition of the HDL(2) or HDL(3) subfractions. Selective uptake by the scavenger receptor BI was not inhibited by RAP, excluding its involvement. Furthermore, in SW872 cells in which LRP was reduced to 14% of control levels by stable antisense expression, selective uptake was attenuated by at least 33%, confirming a role for LRP in this process. RAP, alpha(2)-macroglobulin, lactoferrin, and suramin (individually or in paired combinations) also attenuated selective uptake of HDL-CE by primary human adipocytes by about 40%. On the other hand, human skin fibroblasts express LRP abundantly but lack the capacity for selective uptake, demonstrating that other molecules are required. In SW872 cells, exogenous apoE or LpL can facilitate selective uptake but only the apoE-enhanced uptake can be inhibited by RAP, implicating apoE as a likely co-mediator. We discuss the possible mechanisms by which the endocytic receptor, LRP, can mediate selective uptake.

Suppressive effects of Aspergillus fumigatus culture filtrates on human alveolar macrophages and polymorphonuclear leucocytes.

Aspergillus spp., especially A. fumigatus (Af) can colonize the airways and the lungs with localized underlying conditions and further invade the surrounding lung tissues, even in subjects without systemic predisposing factors, presumably by escaping the local host defences. To clarify the mechanisms of colonization and invasion of Af, we investigated the in vitro effects of Af culture filtrates (ACFs) on the functions of human alveolar macrophages (AMs), and polymorphonuclear leucocytes (PMNs). ACFs were obtained by culturing clinically isolated Af in Medium-199 at 37 degrees C for 5 days. In the study of phagocytosis of Af conidia by human AMs, 52% of AMs ingested conidia during a 60 min incubation period in Medium-199. However, the percentage decreased to 24% when incubated with a final concentration of 30% ACF in Medium-199. With respect to the antichemotactic activity on human PMNs, 3% ACF was sufficient for significant suppression, and 30% ACF completely inhibited the migration of PMNs. In addition, phorbol myristate acetate (PMA)-induced O2- release from PMNs was significantly suppressed in Medium-199 which included 12.5% ACF or more. The antichemotactic activity of ACF was partially abolished by trypsin or chicken egg ovomacroglobulin. When ACF was separated into two fractions (molecular weight > 10 and < 10 kDa) by dialysis and centrifugation through CL-LGC filters, both fractions retained the antichemotactic activity. We conclude that Af produce several antiphagocytic factors, which can be responsible for the colonization of Af in the bronchopulmonary tissues and allow this species to invade surrounding lung tissues in pulmonary aspergillosis by suppressing local host defences.

Role of bradykinin in microbial infection: enhancement of septicemia by microbial proteases and kinin.

Data presented herein will show that bradykinin, microbial proteases which activate the kinin generating cascade, and kininase inhibitors can enhance septicemia by approximately 10 to 100 fold in mice infected intraperitoneally (i.p.) with a strain of bacteria, Pseudomonas aeruginosa 621, which does not usually produce a kinin generating protease. Bacterial spreading was evaluated either in the blood or in the spleen by colony formation on agar plates. Using the P. aeruginosa kaguma strain which produces a large amount of proteases, further experiments were carried out. Results showed that two different protease inhibitors (ovomacroglobulin and a synthetic peptide inhibitor against pseudomonal elastase) as well as a kinin antagonist suppressed bacterial dissemination to 1/10-1/100 of control. Similar results were observed in experiments using Vibrio vulnificus. These data support the hypothesis that microbial proteases and especially bradykinin is responsible for facilitation of microbial dissemination in vivo.

The effects of ovomacroglobulin on gingival wound healing in rats.

The effects of ovomacroglobulin (OMG), an alpha 2-macroglobulin-like protease inhibitor, were tested on periodontal surgical would healing in 60 Wistar rats. The animals were divided into two groups, one receiving topical application of 0.1% wt/wt OMG ointment and the other receiving ointment base (base). Rats were killed at one, three and seven days after surgery for histological and immunohistochemical observation. Compared with base group samples, OMG samples displayed enhanced capillary formation on anti-laminin-stained sections from day-3 specimens and a greater quantity of collagen fibers on Azan-Mallory-stained sections from day-7 specimens. Results were quantified using an automatic computerized pixel image analyzer. Hematoxylin-eosin-stained sections revealed that the length of regenerated junctional epithelium was shorter in the OMG group than in the base group. The data indicate that the application of OMG to surgical wounds accelerated fibroblast growth, collagen deposition, and capillary formation in granulation tissue. Thus, OMG could be a useful healing promoter for flap surgery.

Effects of protease inhibitors on growth of Serratia marcescens and Pseudomonas aeruginosa.

The growth inhibitory effects of chicken egg white ovomacroglobulin (ovoM) on Serratia marcescens and Pseudomonas aeruginosa were studied. The growth of protease-producing strains was greater than that of the strains producing little protease, and was inhibited in a dose-dependent manner by ovoM, a potent protease inhibitor. Dose-dependent enhancement of growth of strains of S. marcescens and P. aeruginosa that produce little protease was observed with the medium treated with proteases. These results indicate that extracellular proteases produced by the organisms augment their growth and that inhibition of the proteases results in suppression of growth.

Inhibition of inflammatory proteinase, medullasin, by alpha 2-macroglobulin and ovomacroglobulin.

The in vitro activity of inflammatory proteinase, medullasin, was stoichiometrically inhibited by a serum proteinase inhibitor, alpha 2-macroglobulin, and its homolog, chicken ovomacroglobulin. The two inhibitors were cleaved by medullasin only in the bait region. The effectiveness of alpha 2-macroglobulin to inhibit medullasin in competition with alpha -1-proteinase inhibitor was measured under a simulated in vivo condition and an estimation was made that about 60-70% medullasin is inhibited by alpha-1-inhibitor and 30-40% by alpha 2-macroglobulin.

[The inhibitory effects of chicken ovomacroglobulin on collagenolytic activity in Bacteroides gingivalis culture supernatant, human PMN and human gingival crevicular fluid].

We examined in vitro the inhibitory effects of ovomacroglobulin on collagenolytic activity in Bacteroides gingivalis (B. gingivalis) culture supernatant, in human peripheral blood polymorphonuclear leucocytes (PMN), and in gingival crevicular fluid (GCF) from periodontitis patients. Measurement of collagenolytic activity was conducted with a CollagenoKit CLN-100 using FITC-conjugated type I collagen. The FITC-conjugated collagen was reacted with the sample in solution, and the residue was selectively degenerated at 35 degrees C and removed with ethanol. The fluorescence of the removed residue was then measured. The collagenolytic activity from B. gingivalis displayed dose dependent inhibition as high as 81.4% following addition of ovomacroglobulin at 224 micrograms/ml. The collagenolytic activity from human peripheral blood PMN showed, as a result of addition of 1,600 micrograms/ml of ovomacroglobulin, inhibition as high as 62.4%. The collagenolytic activity from human GCF, which was obtained from patients with different degrees of periodontal disease, exhibited as high as 71.0% inhibition after addition of 1,600 micrograms/ml ovomacroglobulin. Ovomacroglobulin showed almost the same level of inhibition obtained from alpha 2-macroglobulin, which was measured as a positive control. It was also recognized by SDS-PAGE that collagenolytic activity was inhibited after preincubation with added ovomacroglobulin. This collagenolytic activity, which dissolved the collagen substrate, was derived from B. gingivalis and human GCF. The above results demonstrate that ovomacroglobulin inhibits collagenolytic activity from B. gingivalis, human PMN, and human GCF.

Pathogenic capacity of proteases from Serratia marcescens and Pseudomonas aeruginosa and their suppression by chicken egg white ovomacroglobulin.

The pathogenicities of three proteases from Serratia marcescens, two proteases from Pseudomonas aeruginosa, and one thermolysin from Bacillus stearothermophilus were examined. All proteases tested caused acute liquefactive necrosis of the cornea and descemetocele formation in guinea pig eyes after intrastromal injection, with the exception of the 60-kilodalton protease from S. marcescens, which produced only an opaque lesion. When injected into guinea pig skin, the protease also enhanced vascular permeability, which was followed by edema formation. The permeability-enhancing activity of the proteases increased in parallel with the concentration of the enzymes. When tested in vitro for its effect on these bacterial proteases, chicken egg white ovomacroglobulin (ovoM) inhibited the enzymatic activity of all the proteases after a short incubation period at an enzyme/inhibitor ratio (molar) of 1:1 to 1:4 or at a lower concentration after a longer incubation period. Such treatment of the proteases with chicken egg white ovoM before injection intrastromally into the eyes or intradermally into the clipped flanks of guinea pigs protected the cornea from destruction or completely prevented the permeability reaction and edema formation. No inhibitory effects of plasma protease inhibitors against these bacterial proteases were noted. Since the proteases are critical in the pathogenic processes caused by the bacteria, these results suggest a beneficial effect of ovoM against bacterial infections.

Venom resistance in the hedgehog, Erinaceus europaeus: purification and identification of macroglobulin inhibitors as plasma antihemorrhagic factors.

Hedgehog (Erinaceus europaeus) plasma contains factor(s) which neutralize the hemorrhagic activity of European viper (Vipera berus) venom. These antihemorrhagic factor(s) were purified by gel filtration on Sephacryl S-200 and chromatography on Cibacron Blue Sepharose. The macroglobulin fraction obtained was characterized for proteinase inhibiting activity, molecular weight and purity by polyacrylamide gel electrophoresis and immunological cross-reactivity and was found to contain the three macroglobulin proteinase inhibitors--alpha 2-macroglobulin, alpha 2-beta-macroglobulin and beta-macroglobulin. The purified macroglobulins were totally able to neutralize Vipera berus venom hemorrhagic activity, but no distinction between them in this respect was possible.

Unusual properties of crocodilian ovomacroglobulin shown in its methylamine treatment and sulfhydryl titration.

The inhibitory activity of chicken and crocodilian ovomacroglobulins against trypsin was measured before and after their incubation with methylamine. The result for crocodilian ovomacroglobulin showed that methylamine treatment destroyed half of its activity, in unique contrast to human alpha 2-macroglobulin and chicken ovomacroglobulin for which methylamine either destroys the inhibitory activity of the former completely or does not affect that of the latter at all. Free sulfhydryl groups of chicken and crocodilian ovomacroglobulins were titrated with 5,5'-dithiobis(2-nitrobenzoic acid) before and after incubation with trypsin. Prior to the incubation with trypsin the chicken and crocodilian proteins respectively had 0 and 1 titratable sulfhydryl per molecule of Mr 720,000. After treatment with trypsin the crocodilian protein had 3.5-4 titratable sulfhydryls, whereas there were no titratable sulfhydryls in the chicken protein. After denaturation of the crocodilian protein in sodium dodecyl sulfate at 100 degrees C the number of titratable sulfhydryls was 4. Chicken ovomacroglobulin again did not have an appreciable number of titratable sulfhydryls under similar denaturing conditions. Incubation of crocodilian protein with [14C]methylamine showed an incorporation of at least 2 mol of methylamine per molecule. The result indicated the presence of three intramolecular thiol ester bonds in crocodilian ovomacroglobulin with differential stability against external perturbations.

Tumor-induced growth-inhibitory activity isolated from the Yoshida ascites fluid by extraction with methanol.

Growth-inhibitory activity was isolated from the Yoshida ascites fluid by sequential precipitation with polyethylene glycol, extraction with methanol, LH 20 Sephadex chromatography and preparative agarose gel electrophoresis. The cell non-specific activity was tumor-related as far as analogous fractions prepared from normal sera were inactive. Flow cytometric analysis indicates that the inhibition of cell growth was caused by blockage of the G1-S and possibly the G2-M phase transitions. The active component migrates electrophoretically associated to an unidentified alpha 1-antigen. In aqueous solution the molecular size of the inhibitor is ill defined, due to a tendency to autoaggregation and hydrophobic interaction with the chromatographic media. The molecular weight of the inhibitor as estimated by LH 20 Sephadex chromatography in methanol is approximately 350 daltons. This chromatographic fraction contains prostaglandin-E2 cross-reactive material in amounts suggesting the participation of a prostaglandin derivative in the observed growth-inhibitory activity.

Hen egg white ovomacroglobulin has a protease inhibitory activity.

Hen egg white ovomacroglobulin purified by Miller and Feeney without reference to its activity was shown to have a protease inhibitory activity towards trypsin, papain, and thermolysin. It has four subunits of equal molecular weight (175,000 by SDS-PAGE) and each two of which are disulfide bonded. Upon incubation with trypsin it yields a fragment of Mr = 80,000 plus smaller ones. The subunit composition, amino acid composition and a newly found protease inhibitory activity place ovomacroglobulin as a closely related protein to human serum alpha 2-macroglobulin.

Uptake of proteinase-alpha-macroglobulin complexes by macrophages.

Complexes of labelled proteinases (subtilopeptidase A, trypsin) with serum alpha 1-macroglobulin or alpha 2-macroglobulin are rapidly taken up in vitro by rabbit alveolar macrophages and peritoneal macrophages but not by mixed rabbit peripheral blood leukocytes. Enzyme, not bound to alpha 1- or alpha 2-macroglobulin, does not become associated with alveolar macrophages. Chemically inactivated subtilopeptidase A does not bind to alpha 1- or alpha 2-macroglobulin; chemically inactivated subtilopeptidase A in mixtures with alpha 1 - or alpha 2-microglobulin, does not interact with alveolar macrophages. Blocking experiments confirmed that the interaction of proteinase with alveolar macrophages is complex specific; uptake of labelled complex was prevented by the simultaneous addition of macroglobulin complexes formed with non-labelled subtilopeptidase A, subtilopeptidase B, trypsin or chymotrypsin but not by macroglobulin alone. The findings demonstrate a complex-specific interaction between proteinase-alpha-macroglobulin complexes and macrophages.

Enhancement of migration inhibitory factor activity by plasma esterase inhibitors.

The plasma esterase inhibitors alpha2-macroglobulin, alpha1-antitrypsin, C1-inhibitor, antithrombin-heparin cofactor, and, as previously described, soybean trypsin inhibitor (Kunitz) and diisopropylphosphorofluoridate (9) enhance the response of guinea pig macrophages to migration inhibitory factor. To obtain this effect, macrophages are incubated with inhibitors prior to assay. The data suggest that (a) the enhancement of migration inhibitory factor response is due to the inhibition of esterases associated with the macrophage through a distinct active site on the inhibitors, and (b) that the active sites of antithrombin-heparin cofactor and soybean trypsin inhibitor, which interact with the macrophage enzymes, are different from the active sites of these inhibitors which interact with thrombin and trypsin respectively. Chemical modification of the active site of antithrombin-heparin cofactor for thrombin and of soybean trypsin inhibitor for trypsin does not affect their capacity to enhance the migration inhibitory factor response. From studies with thrombin, it was known that antithrombin-heparin cofactor has a heparin binding site. Addition of heparin was found to prevent the migration inhibitory factor-enhancing effect of antithrombin-heparin cofactor. The present results suggest that plasma esterase inhibitors may play a regulatory role in the response of macrophages to mediators of cellular immunity.

On the inhibition of elastase by serum. Some distinguishing properties of alpha1-antitrypsin and alpha2-macroglobulin.

1. The influence of serum on the elastolytic and esterolytic activity of elastase has been studied. With both substrates the inhibition curves are linear. 1 ml of normal human serum inhibits the activity of 0.77 mg of pure porcine elastase. 2. Elastase binds faster with alpha2-macroglobulin (k = 3.4-10(6) M-1 S-1) than it does with alpha1-antitrypsin (k = 5-10(5) M-1 S-1). 3. The dissociation constant of the alpha-antitrypsin -elastase complex is much lower than that of the alpha2-macroglobulin-elastase complex but both complexes are very stable (Ki less than 10(-10) M). 4. Protein pi (inter-alpha-inhibitor) does not inhibit elastase.

Immunosuppresive effect of a human hepatic glycoferroprotein, alpha2H globulin. A study on the transformation of normal human lymphocytes.

A macroglycoferroprotein of hepatic orgin, alpah2H globulin, the serum level of which increases a few weeks or months before local recurrence of metastases, has been essayed for its immunosuppressive activity. The study was carried out using the lymphoblastic transformation test and was judged by tritiated thymidine incorporation and microscopic examination. PHA-induced blast transformation of 97 per cent of normal donor lymphocytes is inhibited by 100 mug/ml of alpha2H globulin. This inhibitory effect is proportional to the quantity of added alpha2H globulin. In is obvious with a concentration of 2-5 mug/ml, a frequently observed level in the serum of patient with tumours. Preincubation of lymphocytes with alpha2H globulin renders more effective the inhibitory action on PHA-induced transformation. A mechanism of competition between PHA and alpha2H globulin is suggested by preincubation and the inhibitory effect related to the doses. However, microscopic observation shows that alpha2H globulin acts on the earliest events occurring to the stimulated lymphocytes, by inhibiting cytoplasmic RNA and protein synthesis. The alpha2H globulin effect may not only have an immunosuppresive activity but it may have a more general effect, for example blocking or modifying cellular respiration.