114 BOVINE EMBRYO-MATERNAL RECOGNITION MAY OCCUR EARLIER IN AI THAN IN EMBRYO TRANSFER (ET)

Embryo-maternal recognition is known to be mediated by the trophoblast and/or its secretory product during the preimplantation period. However, it was recently proposed that embryo-maternal recognition (along with the maternal immune system) could be activated by zona pellucida-degradation products including oligosaccharide chains from very early stage embryos (Fujiwara et al. 2009 J. Reprod. Immunol. 81, 1–8). If this is true, we predict that mammalian mothers recognise the presence of an embryo immediately after fertilization in vivo. The purpose of the present study was to compare the expressions of immune tolerance genes in bovine endometrial-luminal lymphoid (ELL) cells collected from animals after AI or embryo transfer (ET). ELL cells were collected from recipient cows inseminated with frozen–thawed semen on Day 0 (=oestrus, n = 8) and from cows that received a transferred embryo on Day 7 (n = 8) of the oestrous cycle. On Days 9 and 11, ELL cells ipsilateral to the corpus luteum were flushed non-surgically from four cows of each group using Ringer's solution (500 mL). To eliminate large cell clusters of endometrium and the embryo (blastocyst), the flushing medium was passed through an embryo collection filter (EmCon filter, 75 μm stainless steel screen). A single viable blastocyst was collected from each recipient cow. The recovered flushing medium containing ELL cells was centrifuged. The ELL cells were suspended in PBS and separated by Lympholyte-H (Cedarlane, Ontario, Canada) gradient centrifugation. Using RT-real-time PCR, transcripts for four immune tolerance genes in ELL cells from AI or ET examined were transforming growth factor-β (TGF-β), macrophage-colony stimulating factor (M-CSF), interleukin-10 (IL-10), and forkhead box P3 (Foxp3). Data were normalized to that of an endogenous control (glyceraldehyde-3-phosphate dehydrogenase) and analysed using ANOVA followed by Scheffe′s test. Transcripts for TGF-β, M-CSF, IL-10, and Foxp3 were detected in all RT-samples derived from ELL cells on Days 9 and 11 of the oestrous cycle. Transcript levels of TGF-β, M-CSF and IL-10 in the AI group were the same as those of the ET group (P > 0.05), although the transcript level of Foxp3, a master regulator of the function of regulatory T-cells, in the AI group was significantly higher than that of the ET group on Days 9 and 11 (P < 0.05). Furthermore, the transcript level of Foxp3 in the ET group on Day 11 was significantly higher than that of the ET group on Day 9 (P < 0.05). These results indicate that the embryo-maternal recognition in AI occurs earlier than in ET, and suggest that cows recognise an embryo earlier than those generally believed.

Anti-tumour effects of transcatheter arterial embolisation administered in combination with thalidomide in a rabbit VX2 liver tumour model

OBJECTIVE

Using a liver tumour model we investigated whether thalidomide enhances the anti-tumour effect of transcatheter arterial embolisation (TAE).

METHOD

First, the viability of VX2 tumour cells co-cultured with thalidomide in a 21% and 1% O(2) atmosphere was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Second, we randomly assigned 20 rabbits bearing VX2 liver tumours to 4 groups: Group 1 (thalidomide plus TAE), Group 2 (TAE only), Group 3 (thalidomide only) and Group 4 (control). Thalidomide was orally administered for 5 days. The anti-tumour effects were assessed by the tumour proliferation rate using MRI and by immunohistochemical analysis of the area of intratumoural vessels. Analysis of variance and Tukey's honestly significant difference test were used for statistical analysis.

RESULTS

The viability of cells grown under hypoxic and normal conditions was not significantly different, nor was there a difference among the four groups. The tumour size increased by 55.9±29.3% in Group 1, 250.6±73.3% in Group 2, 355.2±51.7% in Group 3 and 424.7±110.7% in Group 4; the difference between Group 1 and the other three groups was significant. The area of intratumour vessels in specimens was 0.22±0.28% in Group 1, 0.42±0.29% in Group 2, 1.44±1.00% in Group 3 and 6.00±2.17% in Group 4; the difference between Group 1 and the other groups was statistically significant, as was the difference between Groups 3 and 4.

CONCLUSION

Thalidomide used in combination with TAE enhanced anti-tumour effects in rabbits bearing VX2 liver tumours.

LTD₄ induces HB-EGF-dependent CXCL8 release through EGFR activation in human bronchial epithelial cells

Airway epithelial cells release proinflammatory mediators that may contribute to airway remodeling and leukocyte recruitment. We explored the hypothesis that leukotriene D₄ (LTD₄) may trigger the release of proremodeling factors through activation of the EGF receptor (EGFR). We particularly focused on the effects of LTD₄ on release of heparin-binding EGF-like factor (HB-EGF) and IL-8 (CXCL8), a potent neutrophil chemoattractant that may be released downstream of EGFR activation. To address this hypothesis, both primary (NHBE) and transformed bronchial human epithelial cells (BEAS-2B) were grown on an air-liquid interface and stimulated with LTD₄. HB-EGF and CXCL8 were evaluated by ELISA in cell culture supernatants. To explore the EGFR signaling pathway, we used a broad-spectrum matrix metalloproteinase (MMP) inhibitor, GM-6001, two selective EGFR tyrosine kinase inhibitors, AG-1478 and PD-153035, an HB-EGF neutralizing antibody, and a specific small interfering RNA (siRNA) against the EGFR. Expression of the CysLT₁ cysteinyl leukotriene receptor was demonstrated by RT-PCR and immunocytochemistry in both BEAS-2B and NHBE cells. Four hours after stimulation with LTD₄, HB-EGF and CXCL8 were significantly increased in cell culture supernatant. GM-6001 and montelukast, a specific CysLT₁ receptor antagonist, blocked the LTD₄-induced increase in HB-EGF. All inhibitors/antagonists decreased LTD₄-induced CXCL8 release. siRNA against EGFR abrogated CXCL8 release following stimulation with LTD₄ and exogenous HB-EGF. These findings suggest LTD₄ induced EGFR transactivation through the release of HB-EGF in human bronchial epithelial cells with downstream release of CXCL8. These effects may contribute to epithelial-mediated airway remodeling in asthma and other conditions associated with cysteinyl leukotriene release.

EGF receptor activation during allergic sensitization affects IL-6-induced T-cell influx to airways in a rat model of asthma

EGF receptor (EGFR) is involved in cell differentiation and proliferation in airways and may trigger cytokine production by T cells. We hypothesized that EGFR inhibition at the time of allergic sensitization may affect subsequent immune reactions. Brown Norway rats were sensitized with OVA, received the EGFR tyrosine kinase inhibitor, AG1478 from days 0 to 7 and OVA challenge on day 14. OVA-specific IgE in serum and cytokines and chemokines in BAL were measured 24 h after challenge. To evaluate effects on airway hyperresponsiveness (AHR), rats were sensitized, treated with AG1478, intranasally challenged, and then AHR was assessed. Furthermore chemotactic activity of BALF for CD4(+) T cells was examined. The eosinophils, neutrophils and lymphocytes in BAL were increased by OVA and only the lymphocytes were reduced by AG1478. OVA significantly enhanced IL-6 concentration in BAL, which was inhibited by AG1478. However AHR, OVA-specific IgE and IL-4 mRNA expression in CD4(+) T cells were not affected by AG1478. BALF from OVA-sensitized/challenged rats induced CD4(+) T-cell migration, which was inhibited by both AG1478 treatment in vivo and neutralization of IL-6 in vitro. EGFR activation during sensitization may affect the subsequent influx of CD4(+) T cells to airways, mainly mediated through IL-6.

Promotion of beta-cell differentiation by the alkaloid conophylline in porcine pancreatic endocrine cells

We previously found that conophylline, an alkaloid isolated from the leaves of Ervatamia microphylla, induced beta-cell differentiation in rat pancreatic acinar carcinoma cells and in cultured fetal rat pancreatic tissue and that it also decreased the blood glucose level in streptozotocin-treated fetal rats. In the present research, we looked into the effect of conophylline on the differentiation of newborn pig pancreatic endocrine cells into insulin-secreting cells. Conophylline potentiated the differentiation of monolayer cells into insulin-producing cells in the presence of nicotinamide in 3 weeks. Next we prepared islet-like cell clusters (ICC). Cononophylline together with nicotinamide also increased the number of insulin-producing cells and the insulin content in ICC in 3-6 weeks. The ICC thus prepared were sensitive to the glucose concentration for the insulin secretion. Conophylline increased the mRNA expression of PDX-1, neurogenin3, neuroD/Beta2, and insulin in ICC. Thus, the vinca alkaloid conophylline potentiated beta-cell differentiation in porcine pancreatic endocrine-rich cells in cluster cultures. Pig pancreatic cells are practical candidate for use in transplantation therapy. Conophylline may thus be useful for the large-scale preparation of porcine insulin-producing cells for the regeneration therapy of type-1 diabetes mellitus.

226 EFFECT OF AMMONIA IN BOVINE FOLLICULAR FLUID AND OOCYTE MORPHOLOGY DERIVED FROM ABATTOIR OVARIES

In cattle, high intake of crude protein elevates rumen ammonia and blood urea nitrogen and has been associated with decreased fertility. The aim of this study was to analyze the concentration of ammonia in bovine follicular fluid derived from abattoir ovaries and to examine the relation between ammonium concentration and morphology of oocytes from antral follicles. In the first experiment, follicular fluid was collected within 1 h of slaughter from 3919 small (2-5 mm in diameter), 366 medium (6-9 mm), and 159 large (10-20 mm) follicles from 203 ovaries. Ammonium concentration was analyzed in 6 batches pooled from follicular fluids of each size (derived from 15, 39, 7, 36, 81, and 25 ovaries, respectively). Ammonium concentration was measured by the microdiffusion method using an Ami Check Meter kit (Kyoto Daiichi Kagaku Co., Ltd., Japan). In the second experiment, follicular fluids were aspirated from small (2-5 mm) follicles of 38 cows to evaluate the relationship between ammonium concentration and oocyte morphology. Oocytes were classified into 4 morphological categories according to the surrounding cumulus cells (Konishi M et al. 1996 Theriogenology 45, 573-581): grade 1 (≥5 layers); grade 2 (3-4 layers); grade 3 (1-2 layers); and grade 4 (denuded, degenerated cumulus cell mass or ooplasm). The oocyte morphology for the low-ammonium group (<330 μmol, 239 oocytes from 19 cows) and high-ammonia group (≥330 μmol, 255 oocytes from 19 cows) was compared. Statistical significance was tested by chi-square test or t-test Ammonium con- centrations of small (281.8 ± 20.0 μM), medium (175.4 ± 15.8 μM), and large (96.3 ± 9.3 μM) follicles were significantly different (P < 0.0001). Ammonium concentrations in follicular fluid of the 38 cows ranged from 180.6 to 802.4 μM. In a comparison of oocyte morphology between the low- (263.8 ± 41.6 μM) and high-ammonium (423.0 ± 108.9 μM) groups, the number of grade 1, 2, 3, and 4 oocytes in the former (80, 68, 18, and 73, respectively) were not significantly different from the numbers in the latter (96, 61, 27, and 71, respectively; P = 0.30-0.99). These results indicate that, in follicles of different sizes derived from abattoir ovaries, the ammonium concentration was higher in small follicles than in the other sizes of follicles. However, there was no evidence that in vivo exposure of bovine oocytes to ammonium badly influenced oocyte morphology. Further studies are needed to examine the relationship between ammonium concentration and the developmental potential of oocytes.

SAR analysis of a re-entrant resonant cavity applicator for brain tumor hyperthermia treatment with a 3-D anatomical human head model

A re-entrant resonant cavity applicator system for non-invasive brain tumor hyperthermia treatments was presented. We have already confirmed the effectiveness of the heating properties of this heating system with cylindrical agar phantoms and with computer simulations.

277 EFFECTS OF ERYTHROCYTE AND ERYTHROCYTE HEMOLYSATE ON BOVINE PREIMPLANTATION EMBRYO DEVELOPMENT IN VITRO UNDER REACTIVE OXYGEN SPECIES CONDITION

Reactive oxygen species (ROS) damage preimplantation embryos by increasing DNA fragmentation, leading to early embryonic death. Erythrocytes have been shown to protect other cells and tissues against ROS. In mice, erythrocytes were recently found to improve the early development of embryos by their antioxidant effect. The purpose of the present study was to examine the effect of erythrocytes on the in vitro development of bovine IVF embryos in medium supplemented with ROS. COCs were aspirated from ovaries collected from a local slaughterhouse and were cultured for 22 h in TCM-199 containing 5% fetal bovine serum. IVF was performed using an IVF100 (Research Institute for the Functional Peptides, Yamagata, Japan) according to the manufacturer’s instructions. In experiment 1, IVF embryos were cultured in CR1aa medium supplemented with an oxidizing agent, 0.5 mM hypoxanthine and 0.01 U mL-1 xanthine oxidase (HX/XOD), in the presence and absence of erythrocytes (5 × 104, 5× 105, 5×106, and 5 × 107 erythrocytes mL-1). In experiments 2 and 3, the development of embryos under the condition without ROS was assessed in the presence and absence of erythrocytes (5 × 106 erythrocytes mL-1) or erythrocyte hemolysate (hemoglobin concentration of 1.9 g L-1), respectively. At 7 days after in vitro culture, the development to the blastocyst stage of IVF embryos was examined using a stereomicroscope. Data were analyzed using Fisher’s PLSD test and Student’s t-test In experiment 1, the presence of HX/XOD significantly inhibited embryo development to the blastocyst stage in vitro (P < 0.05). The addition of erythrocytes to medium supplemented with HX/XOD markedly improved preimplantation development (Table 1). In experiments 2 and 3, supplementation of erythrocytes or erythrocyte hemolysate promoted the development of embryos to the blastocyst stage (experiment 2: erythrocyte 42.4 ± 3.1%, control 28.5 ± 5.7%, P < 0.1; experiment 3: erythrocyte hemolysate 39.1 ± 3.3%, control 30.2 ± 1.0%, P < 0.1). In conclusion, we suggest that the addition of erythrocytes to culture medium can counteract the negative effects of ROS on embryo development and blastocyst formation. Table 1.Effect of HX/XOD and erythrocyte supplementation on embryo development to blastocyst stage

A combination of cisplatin-eluting gelatin microspheres and flavopiridol enhances anti-tumour effects in a rabbit VX2 liver tumour model

The aim of this study was to investigate whether the combination of cisplatin-eluting gelatin microspheres (GMSs) and flavopiridol enhances anti-tumour effects in a rabbit VX2 liver tumour model. Tumour-bearing rabbits (n = 21) were divided into five groups and infused from the proper hepatic artery. Group 1 (n = 5) received cisplatin-eluting GMSs (1 mg kg(-1)) and flavopiridol (3 mg kg(-1)), group 2 (n = 5) cisplatin-eluting GMSs alone (1 mg kg(-1)), Group 3 (n = 5) flavopiridol (3 mg kg(-1)), Group 4 (n = 3) GMSs alone (1 mg kg(-1)), and Group 5 (n = 3) was the control group receiving physiological saline (1 ml kg(-1)). On days 0 and 7 after procedures the liver tumour volume was measured using a horizontal open MRI system and the relative tumour volume growth rates for 7 days after treatment were calculated. On T(1) weighted images, the tumours were visualised as circular, low-intensity areas just below the liver surface. After treatment, the signals remained similar. The relative tumour volume growth rate for 7 days after treatment was 54.2+/-22.4% in Group 1, 134.1+/-40.1% in Group 2,166.7+/-48.1% in Group 3, 341.8+/-8.6% in Group 4 and 583.1+/-46.9% in Group 5; the growth rate was significantly lower in Group 1 than the other groups (p<0.05). We concluded that in our rabbit model of liver tumours the combination of cisplatin-eluting GMSs and flavopiridol was effective.

Heating properties of non-invasive hyperthermia treatment for abdominal deep tumors by 3-D FEM

This paper discusses the heating properties of a new type of hyperthermia system composed of a re-entrant type resonant cavity applicator for deep tumors of the abdominal region. In this method, a human body is placed in the gap of two inner electrodes and is non-invasively heated with electromagnetic fields stimulated in the cavity. Here, we calculated temperature distributions of a simple human abdominal phantom model that we constructed to examine the heating properties of the developed hyperthermia system. First, the proposed heating method and a simple abdominal model to calculate the temperature distribution are presented. Second, the computer simulation results of temperature distribution by 3-D FEM are presented. From these results, it was found that the proposed simple human abdominal phantom model composed of muscle, fat and lung was useful to test the heating properties of our heating method. Our heating method was also effective to non-invasively heat abdominal deep tumors.

The effects of repeated allergen challenge on airway smooth muscle structural and molecular remodeling in a rat model of allergic asthma

The effects of remodeling of airway smooth muscle (SM) by hyperplasia on airway SM contractility in vivo are poorly explored. The aim of this study was to investigate the relationship between allergen-induced airway SM hyperplasia and its contractile phenotype. Brown Norway rats were sensitized with ovalbumin (OVA) or saline on day 0 and then either OVA-challenged once on day 14 and killed 24 h later or OVA-challenged 3 times (on days 14, 19, and 24) and killed 2 or 7 days later. Changes in SM mass, expression of total myosin, SM myosin heavy chain fast isoform (SM-B) and myosin light chain kinase (MLCK), tracheal contractions ex vivo, and airway responsiveness to methacholine (MCh) in vivo were assessed. One day after a single OVA challenge, the number of SM cells positive for PCNA was greater than for control animals, whereas the SM mass, contractile phenotype, and tracheal contractility were unchanged. Two days after three challenges, SM mass and PCNA immunoreactive cells were increased (3- and 10-fold, respectively; P < 0.05), but airway responsiveness to MCh was unaffected. Lower expression in total myosin, SM-B, and MLCK was observed at the mRNA level (P < 0.05), and total myosin and MLCK expression were lower at the protein level (P < 0.05) after normalization for SM mass. Normalized tracheal SM force generation was also significantly lower 2 days after repeated challenges (P < 0.05). Seven days after repeated challenges, features of remodeling were restored toward control levels. Allergen-induced hyperplasia of SM cells was associated with a loss of contractile phenotype, which was offset by the increase in mass.