Sperm-activating proteins obtained from the herring eggs are homologous to trypsin inhibitors and synthesized in follicle cells

The activation of sperm motility by the egg is an ubiquitous phenomenon in the animal kingdom, but the molecules by which the egg activates sperm motility have been clarified in only a few invertebrate species. In the Pacific herring, Clupea pallasii, mature unfertilized eggs release the sperm-activating proteins which are prerequisite to successful fertilization. Complementary DNA clones encoding herring sperm-activating proteins were isolated from a herring ovarian complementary DNA library and amino acid sequences were deduced. The herring sperm-activating protein(s) is a secretory product(s) with a strong homology to Kazal-type trypsin inhibitors, such as mammalian acrosin inhibitors. The sperm-activating proteins were globally distributed in the outermost layer of the egg chorion and its gene was found to be expressed in the follicle cells which surround developing oocytes. These results suggest that in the Pacific herring, trypsin inhibitor-like proteins are synthesized in the follicle cells, secreted, accumulated in the egg chorion during oocyte development, and released into the milieu at spawning to activate the motility of spermatozoa at the time of gamete interaction.

[Clinical effect of high-flow pulsatile cardiopulmonary bypass in coronary artery bypass grafting]

The effect of high-flow pulsatile cardiopulmonary bypass was evaluated in 36 patients undergoing coronary artery bypass grafting in our unit. The patients were divided into two groups, based on cardiopulmonary bypass (CPB) flow; high (3.0 +/- 0.2 l/min/m2), or moderate (2.4 +/- 0.2 l/min/m2). Multidose cold crystalloid cardioplegia was administered for myocardial protection. Pulsatile flow during CPB was used and systemic perfusion pressure was maintained between 50 and 80 mmHg. Preoperatively, there were no differences between groups in left ventricular ejection fraction or extent of coronary artery disease. The times required for CPB and weaning from CPB were significantly shorter in high-flow group than moderate-flow group. The urinary output during CPB was significantly higher in high-flow group than moderate-flow group. Postoperatively, there were no significant differences in the incidence of myocardial infarction, stroke, or 30-day mortality between groups. In conclusion, high-flow pulsatile CPB shortens the length of CPB and does not differ significantly from moderate-flow with respect to mortality and morbidity.

Production of granulocyte/macrophage and macrophage colony-stimulating factors by human thyrocytes in culture

Monocytes/macrophages can be activated by the colony-stimulating factors (CSFs), granulocyte/macrophage CSF and macrophage CSF, and play a pivotal role in immune and inflammatory responses. We examined whether human thyrocytes can produce these CSFs. Interleukin-1 (IL-1) strongly up-regulated the gene and protein expression of the two CSFs. Interferon-gamma stimulated M-CSF expression but inversely suppressed GM-CSF expression in either basal or IL-1-stimulated condition. Thyrocytes prepared from Graves' thyroid tissues produced relatively larger amounts of GM-CSF in response to IL-1 and M-CSF in both basal and IL-1-stimulated conditions when compared to those obtained from normal and adenomatous goiter thyroid tissues. Thyrotropin attenuated M-CSF, but not GM-CSF, production. The present finding indicates that human thyrocytes themselves produce both GM-CSF and M-CSF, and thus may participate in immune and inflammatory responses through these CSFs production.

Decreased sulfhydryl groups in the reperfused myocardial tissue of a rat model of myocardial infarction

The aim of this study was to determine whether myocardial injury resulting from temporary ischemia followed by reperfusion can be measured by assaying sulfhydryl groups in the affected tissue of a rat model of myocardial infarction. We studied 3 groups: a control group (n = 6), which underwent surgery without left coronary artery (LCA) ligation; group NoR (n = 9), in which the LCA was ligated for 3 h; and group I + R (n = 7), in which 30 min LCA ligation was followed by 3 h reperfusion. The sulfhydryl group content of myocardial tissue was assayed by measuring the fluorescence produced by incubating heart sections with N-(7-dimethylamino-4-methyl-3-coumarinyl) maleimide (DACM), which binds sulfhydryl groups. The fluorescence intensity (FI) of normal and infarcted myocardium was quantified by our computerized system of microscopic fluorophotometry. Indices such as sulfhydryl group content, the size of the low-FI area [% AREA(lower FI)] and the relative decrease in FI [%FI(decrease)]) in the infarct zone were calculated. Both %AREA(lower FI) and %FI(decrease) were significantly higher in the infarcted zone of animals in NoR and I + R groups than in control animals. Both indices were higher in infarct tissue from animals in the I + R group than in the NoR group. These changes suggest that sulfhydryl group content is significantly reduced in tissue that has been subjected to ischemia-reperfusion. Microscopic fluorophotometry, as defined by DACM staining of myocardial tissue, may help to delineate areas of myocardial reperfusion injury.

Eosinophil peroxidase stimulates the release of granulocyte-macrophage colony-stimulating factor from bronchial epithelial cells

BACKGROUND

Asthma is characterized by an accumulation of activated eosinophils in the airway. Eosinophil viability-enhancing activity is present in the sputum of patients with asthma, largely because of granulocyte-macrophage colony-stimulating factor (GM-CSF). Bronchial epithelial cells have been shown to release cytokines including GM-CSF when stimulated with IL-1 beta or tumor necrosis factor-alpha.

OBJECTIVE

The study was designed to determine whether eosinophil peroxidase (EPO) stimulates the release of GM-CSF from bronchial epithelial cells.

METHODS

Epithelial cells (BEAS-2B) were cultured in serum free HD-F12 medium in a 24-well tissue culture plate until they became confluent. The cells were then exposed to EPO (5.9 x 10(-8) to 5.9 x 10(-7) mol/L) for 15 minutes, washed twice, and cultured in 1 ml of HD-F12. The supernatants were harvested at 3, 6, or 24 hours, and GM-CSF concentration was measured by ELISA. BEAS-2B cells were also treated with a system comprising EPO (1.9 x 10(-9) to 5.9 x 10(-8) mol/L) + 10(-5) mol/L H2O2 + 10(-4) mol/L Br for 24 hours.

RESULTS

The GM-CSF concentration in the supernatant pretreated with EPO increased in a time- and concentration-dependent manner compared with control. The release of GM-CSF was not inhibited by catalase but was inhibited by cyclohexamide and by mixing of EPO with heparin, suggesting that the action is due to the cationic property of EPO. When EPO was combined with H2O2 and Br, 5.9 x 10(-9) mol/L EPO + 10(-5) mol/L H2O2 released two times more GM-CSF into the supernatants compared with control.

CONCLUSION

These results suggest that EPO stimulates epithelial cells to release GM-CSF and forms a self-stimulatory cycle.

Expression of monocyte chemoattractant protein-1 mRNA and protein in cultured human thyrocytes

Monocytes as well as lymphocytes infiltrate in the stroma of thyroid tissue in autoimmune and destructive thyroiditis. Monocyte chemoattractant protein-1 (MCP-1) is a cytokine that attracts T-lymphocytes as well as monocytes. Using human thyrocytes in primary cultures, we show that expression of MCP-1 mRNA and protein is remarkably stimulated by both interleukin-1 (IL-1) and tumor necrosis factor-alpha (TNF-alpha), and also that interferon-gamma (IFN-gamma) by itself is a weak stimulant but has a synergistic activity with either IL-1 or TNF-alpha. The finding indicates that MCP-1 can be produced by thyrocytes themselves, suggesting a possible role of thyrocytes on accumulation of monocytes and T-lymphocytes to the tissue from the blood in autoimmune and destructive thyroiditis.

Regulation of inducible nitric oxide production by cytokines in human thyrocytes in culture

We now report on the induction and modulation of NO production by cytokines in primary cultures of human thyrocytes and the effect of NO on iodine organification by human open thyroid follicles in the process of thyroid hormone biosynthesis. Although unstimulated thyrocytes produced little NO (measured as nitrite), interleukin-1 alpha or beta (IL-1 alpha/beta) substantially increased NO formation. Interferon-gamma (IFN-gamma) by itself failed to stimulate NO formation but markedly increased the IL-1-stimulated NO production. Tumor necrosis factor-alpha alone did not induce NO production but did so slightly in the presence of IFN-gamma. Induction of NO formation by thyrocytes upon stimulation with IL-1 alpha + IFN-gamma was accompanied by the synthesis of tetrahydrobiopterin (BH4), an obligatory cofactor of NOS. Coinduction of NO and BH4 synthesis in thyrocytes was preceded by coexpression of messenger RNAs for NOS and GTP cyclohydrolase I (GTPCH), the rate-limiting enzyme for de novo synthesis of BH4. NO synthesis was prevented by an inhibitor of GTPCH, 2,4-diamino-6-hydroxypyrimidine, and this inhibition was completely reversed by administration of sepiapterin, a substrate for BH4 synthesis via pterin salvage pathway. In contrast to IFN-gamma, some cytokines such as interferon-alpha, IL-4, and transforming growth factor-beta 1 inhibited the IL-1-induced NO production. Finally, a possible role of NO on thyroid hormone synthesis was investigated. Iodine organification by human open thyroid follicles was inhibited by two kinds of NO donor but not by cell permeable cyclicGMP analog. Thus, cytokines such as IL-1, IL-1/IFN-gamma, and tumor necrosis factor-alpha/IFN-gamma stimulate human thyrocytes to produce NO; this process can be modulated by other cytokines and coregulated with a cofactor BH4 biosynthesis, and resulting NO may affect cell function including thyroid hormone synthesis.

Role of platelet-activating factor in the release of neutrophil and eosinophil chemotactic attractants from cultured guinea-pig tracheal epithelial cells

Platelet-activating factor (PAF) has been implicated in the pathogenesis of allergic disease, particularly bronchial asthma, by recruitment and activation of inflammatory cells. In an effort to further elucidate this function of PAF, guinea-pig tracheal mucosa was cultured in the presence of PAF in vitro, and culture supernatants were injected intradermally into normal guinea-pigs. After 6 h, recruitment of the inflammatory cells in the tissue was evaluated as a marker of chemotactic activity. Neutrophil and eosinophil recruitment increased significantly 1 h after PAF stimulation, the latter more than the former. After fractionation of the culture supernatant using molecular sieve filters, the fraction of 10-30 kDa showed greater chemotactic activity than the fractions of below 10 kDA or greater than 30 kDA. This activity was inhibited in a dose-dependent manner (over about 1-100 mg/ml) by treatment with anti-granulocyte-macrophage colony-stimulating factor (GM-CSF) antibody. These results suggest that PAF induces the release of chemotactic factors for neutrophils and eosinophils from guinea-pig tracheal epithelial cells, and one of these factors may be GM-CSF.

Monoclonal antibodies against the protein complex that contains the flagellar movement-initiating phosphoprotein of Oncorhynchus keta

We isolated and characterized several monoclonal antibodies against a protein complex containing the flagellar movement-initiating phosphoprotein (MIPP) that appears to play a crucial role in the initiation of flagellar movement in quiescent spermatozoa of Salmonid fish. The effects of the antibodies on the phosphorylation of MIPP, as well as on the initiation of movement, in model sperm cells were studied. Three monoclonal antibodies, namely, FMI7, FMI18, and FMI27, were found specifically to inhibit both the initiation of flagellar movement and the phosphorylation of MIPP. These antibodies did not recognize denatured MIPP; they only recognized the native antigen. FMI7 exclusively recognized the denatured form of a 38-kDa protein, which may possibly be a protein kinase responsible for the phosphorylation of MIPP. Immunofluorescence analysis in situ of model sperm cells with the antibodies showed that the antigen was localized predominantly in the basal structure of the spermatozoon. Thus, the results clearly demonstrate the involvement of MIPP in the initiation of flagellar movement and the control of flagellar motility.

Detailed characterization of a high-molecular-weight glycoprotein secreted by lung cancer cells

A cancer-associated, high-molecular-weight glycoprotein antigen (6B3.Ag) recognized by monoclonal antibody 6B3 was purified from culture medium of human large cell lung carcinoma cell line (HLC-2) and characterized biochemically and immunochemically. The 6B3.Ag was purified more than 1,200-fold with a yield of 30% by salting out, precipitation by acidification at pH 4.5, and chromatographies on Sepharose 4B and concanavalin A-Sepharose. The molecular weight of 6B3.Ag is approximately 1,000,000 and the molecule is a homodecamer of 94,000 subunits. The 6B3.Ag is a glycoprotein containing 22.9% sugars, consisting of both N- and O-glycoside chains. The N-terminal 19 amino acids were determined and only 4 out of 19 amino acid residues were different from those of an antigen, L3, secreted by lung carcinoma cell line Calu-1. The serum level of 6B3.Ag was determined in normal adults as well as patients with various diseases by enzyme-linked immunosorbent assay. The mean serum level of 6B3.Ag was 3.1 micrograms/ml, ranging from 1.6 to 6.2 micrograms/ml in 131 healthy adults. When the cut-off value was set at 6.2 micrograms/ml, the incidence of positive values in the sera was elevated not only in malignant diseases such as hepatoma (73%) and leukemia (62%), but also in benign diseases such as chronic hepatitis (42%) and liver cirrhosis (63%). While the incidence of positive values was elevated in advanced liver diseases, namely, chronic hepatitis, liver cirrhosis and hepatoma, the cancer specificity of 6B3.Ag did not appear to be high.

Effect of needle puncture and intradermal fluid injection on epidermal cell kinetics of albino guinea-pig skin

The flanks of male albino guinea pigs were used to study the effect of needle puncture with or without intradermal (id) injection of 0.1 ml fluid. The center of the raised bleb was marked and biopsies taken 1,4,8,24,50 and 72 hrs after needle puncture and 1 hr after intraperitoneal (ip) injection of tritiated thymidine (3H-TdR). There were no significant differences in labeling index (LI) or mitotic index (MI) 1 hr after id, ip, or subcutaneous (sc) injection nor in percent labeled mitoses, 7 hrs after id or ip injection. The earliest increase in LI (180% above control) occurred 12 hrs after needle puncture, peaked at 24 hrs (ca. 3X control), and returned to control level by 50 hrs. The area affected had a radius of about 5 mm from the point of needle entry or center of the bleb. Within 12 hrs after needle puncture, there was an increase in labeled cells primarily at the periphery of the bleb area, about 4 mm from the point of needle entry. By 24 hrs, the distribution of labeled cells had moved toward the bleb center (LI = 65%). The first increase in mitoses (MI = 2.5%) was seen 24 hrs after needle puncture. It is concluded that id injection introduces no significant error in LI or MI to 8 hrs after needle puncture. It does, however, trigger many noncycling basal cells into DNA synthesis after 8 hrs, and this may increase the rate of transit of these cells to the granular layer.