Effects of a new 12-lipoxygenase inhibitor, daphnodorin A, on angiotensin II-induced vascular contraction in hamster

We studied whether lipoxygenase inhibition suppressed angiotensin II-induced vascular contraction. In the present study, we used a new 12-lipoxygenase inhibitor, daphnodorin A, and an analogue of daphnodorin A, daphnodorin B, which has no inhibitory effects on 12-lipoxygenase. Daphnodorin A at 30 microM and 100 microM significantly suppressed the contractile responses induced by angiotensin 11 (3 x 10(-8) M) in isolated hamster aorta, while daphnodorin B up to 100 microM did not affect the responses. These results suggest that daphnodorin A, but not daphnodorin B, may suppress angiotensin II-induced vascular contractile responses through the inhibition of 12-lipoxygenase.

Transferrin synthesized in cultured human fibroblasts is associated with tubulins and has iron binding capacity

In a previous report (13), using immunocytochemical and fluorescence-labeling techniques, we demonstrated that transferrin is synthesized in cultured human fibroblasts and that it is associated with tubulins in the cells. These morphological findings led us to attempt to elaborate those issues in more detail by biochemical methods. In this report, we were able to prove the association of transferrin produced in cells with tubulins. In addition, the transferrin associated with tubulins was found to bind to iron. These results suggest that endogenous transferrin plays a role in preventing damage caused by free radicals which can be induced by the interaction of iron with the hydrogen peroxide produced in cells.

Development of a sensitive, specific reverse transcriptase polymerase chain reaction-based assay for epithelial tumour cells in effusions

We developed a sensitive and specific method for the detection of epithelial cancer cells in effusions with a two-stage molecular-based assay which combined enrichment for cancer cells by immunomagnetic bead selection and reverse transcriptase polymerase chain reaction (RT-PCR) detection of epithelial glycoprotein 2 (EGP-2) RNA. Preliminary experiments indicated that immunobead selection was essential to avoid occasional false-positive RT-PCR results, and this method detected ten breast cancer cells electively added to 10(7) cytologically negative effusion cells. We studied 110 cases of pleural (n = 68) and peritoneal (n = 42) effusions (30 from patients with known carcinoma and 80 from those without known carcinoma), and the results were compared with cytological findings. Of 18 effusions that were cytologically positive or suspicious for malignant cells, 17 (94%) were positive for EGP-2 RNA (the one negative sample was from a patient who recently received combination chemotherapy). Of 92 cytologically negative samples, 11 (12%) were positive for EGP-2, including six patients with a history of previous or current carcinoma. Our method appears to be highly specific and increases the sensitivity of detection of malignant cells; it may be a useful adjunct to routine cytopathological examination.

Parasite infection and Japanese cedar pollinosis in monkeys

To evaluate the relationship between helminthic parasite infection and sensitization to Japanese cedar (Cryptomeria japonica; CJ) pollen allergens in Japanese monkeys (Macaca fuscata), we examined the parasite infection, presence of anti-pollen allergen IgE and development of pollinosis. Serum samples and fecal specimens were taken from 169 monkeys in five troops, and the presence of IgE antibody for CJ pollen allergen and of helminthic parasite eggs in their feces was examined. Of the 169 monkeys, helminthic parasite eggs from 138 monkeys were detected. The frequency of anti-CJ IgE (19%) and the level of total IgE did not differ significantly between the monkeys with and without parasite eggs. We examined the presence of anti-CJ IgE and pollinosis symptoms in 31 monkeys of a troop; six of the monkeys demonstrated anti-CJ IgE and pollinosis symptoms. Five of these six monkeys had parasite eggs. We found that the monkeys that demonstrated anti-CJ IgE and pollinosis symptoms had helminthic parasite infections. These data suggest that helminthic parasite infection does not reduce the development of clinical signs of CJ pollinosis in Japanese monkeys.

Characterization of paired tumor and non-tumor cell lines established from patients with breast cancer

The goal of our study was to develop a panel of tumor cell lines along with paired non-malignant cell lines or strains collected from breast cancers, predominantly primary tumors. From a total of 189 breast tumor samples consisting of 177 primary tumors and 12 metastatic tissues, we established 21 human breast tumor cell lines that included 18 cell lines derived from primary tumors and 3 derived from metastatic lesions. Cell lines included those from patients with germline BRCA1 and FHIT gene mutations and others with possible genetic predisposition. For 19 tumor cell lines, we also established one or more corresponding non-malignant cell strains or B lymphoblastoid (BL) lines, which included 16 BL lines and 7 breast epithelial (2) or stromal (5) cell strains. The present report describes clinical, pathological and molecular information regarding the normal and tumor tissue sources along with relevant personal information and familial medical history. Analysis of the breast tumor cell lines indicated that most of the cell lines had the following features: they were derived from large tumors with or without axillary node metastases; were aneuploid and exhibited a moderate to poorly differentiated phenotype; were estrogen receptor (ER)- and progesterone receptor (PR)-negative; and overexpressed p53 and HER2/neu proteins. Of 13 patients with primary breast cancers receiving curative intent mastectomies, 7 were dead after a mean period of 10 months. Our panel of paired tumor and non-malignant cell lines should provide important new reagents for breast cancer research.

Oral administration of a dominant T-cell determinant peptide inhibits allergen-specific TH1 and TH2 cell responses in Cry j 2-primed mice

BACKGROUND

Oral immunotherapy with a peptide for allergic immune responses is theoretically a promising therapy but has not been established yet.

OBJECTIVE

To evaluate immune suppressive efficacy of oral administration of an immunodominant peptide, we investigated changes in T-cell proliferation, TH1 - and TH2 -cytokine production, and TH1 - and TH2 -mediated antibody production in mice after oral administration of a peptide.

METHODS

Peptide p246-259, containing a dominant T-cell determinant of Cry j 2, which is the major allergen in Japanese cedar pollen, was used in this study. Groups of mice received p246-259 or PBS alone before or after they were primed intranasally with Cry j 2 and cholera toxin. In another experiment mice were primed intraperitoneally with Cry j 2 and alum. Proliferative response and cytokine production by nasal-associated lymph node cells against Cry j 2 were investigated. Amounts of systemic anti-Cry j 2 IgE and IgG antibodies were also measured.

RESULTS

Oral administration of the peptide to mice before, or even after, the sensitization induced oral tolerance in T-cell responses against the allergen; the tolerance was associated with decreased production of TH1 (IFN-gamma and IL-2) and TH2 (IL-4) cytokines. Allergen-specific TH1 -mediated (IgG2a and IgG2b) and TH2 -mediated (IgG1 and IgE) antibody responses were also inhibited.

CONCLUSIONS

Oral administration of a dominant T-cell determinant peptide induces immunologic tolerance in both TH1 and TH2 cell responses against the whole protein allergen. Our study is the first, to our knowledge, to demonstrate the potential for peptide-based oral immunotherapy in order to treat allergic immune responses.

Identification of potential regulatory elements for the transport of Emp24p

To examine the possibility of active recycling of Emp24p between the endoplasmic reticulum (ER) and the Golgi, we sought to identify transport signal(s) in the carboxyl-terminal region of Emp24p. Reporter molecules were constructed by replacing parts of a control invertase-Wbp1p chimera with those of Emp24p, and their transport rates were assessed. The transport of the reporter was found to be accelerated by the presence of the cytoplasmic domain of Emp24p. Mutational analyses revealed that the two carboxyl-terminal residues, leucine and valine (LV), were necessary and sufficient to accelerate the transport. The acceleration was sequence specific, and the terminal valine appeared to be more important. The LV residues accelerated not only the overall transport to the vacuole but also the ER to cis-Golgi transport, suggesting its function in the ER export. Hence the LV residues are a novel anterograde transport signal. The double-phenylalanine residues did not affect the transport by itself but attenuated the effect of the anterograde transport signal. On the other hand, the transmembrane domain significantly slowed down the ER to cis-Golgi transport and effectively counteracted the anterograde transport signal at this step. It may also take part in the retrieval of the protein, because the overall transport to the vacuole was more evidently slowed down. Consistently, the mutation of a conserved glutamine residue in the transmembrane domain further slowed down the transport in a step after arriving at the cis-Golgi. Taken together, the existence of the anterograde transport signal and the elements that regulate its function support the active recycling of Emp24p.

Human perspiration measurement

We review various methods developed for human perspiration measurement and their physiological applications, with special reference to the performance and application of a new home-made ratemeter and instrumentation with a microscope. Many kinds of humidity sensor based on humidity-sensitive electrical properties have been investigated and placed on the market. Recently a capacitive thin-film humidity sensor was constructed and confirmed to be one of the best humidity sensors for accurately and quickly detecting changes in the relative humidity of gas-flow perfused through a ventilated chamber for human perspiration measurement. In this paper we also introduce a new home-made ratemeter with a capacitive humidity sensor, the electrical output of which is not disturbed by changes in ambient temperature, and new instrumentation for directly observing drops of sweat secreted from eccrine glands in human skin and simultaneously measuring the change in amount of perspiration at the same area of skin. Finally, we review physiological applications of the methods for measuring human palmar perspiration including emotional sweating.

ATP inhibition of proliferation of immortalized human fibroblasts is greater than that of normal human diploid fibroblasts

It is known that cancers develop by a multi-step process. Normal cells are first immortalized, and then transformed into tumorigenic cells. Normal human cells are very rarely immortalized, but once they are, they are relatively easily transformed into tumorigenic cells. This indicates that the immortalization step plays a critical part in the development of human cancers. Thus, elucidation of the mechanisms of this step would shed light on the process of carcinogenesis in human cells. To understand the causes of immortalization, it is important to determine the differences in cellular phenotype between immortalized and normal human cells. In this study, we found that immortalized human fibroblasts were more sensitive to the growth inhibitory effects of ATP than normal human fibroblasts. ADP was as effective as ATP, but AMP, adenosine, and phosphoric acid were not. These results indicate that a high-energy bound of ATP and ADP may contribute to the growth inhibition of the cells. When the immortalized cells were pulse-labeled with [32P]-ATP, 30-, 31-, 33- and 40-kDa membrane fraction proteins were more prominently labeled in the immortalized cells than in the normal cells. At present, the characteristics of these proteins are being investigated.

[An experience of treatment of double positive myeloperoxidase-antineutrophil cytoplasmic antibodies (MPO-ANCA) and anti-glomerular basement membrane antibodies in Goodpasture's syndrome onset of crescentic glomerulonephritis]

A 68-year-old woman was admitted to Kinki University Hospital because of progressive renal failure. She had been well until two months before admission. Laboratory data were as follows: serum creatinine 4.1 mg/dl, BUN 69 mg/dl, MPO-ANCA 33 EU, anti-glomerular basement membrane antibodies (AGBMA) 118 U. Histological findings showed cellular and fibrocellular crescents in many glomeruli. Therefore, we diagnosed rapidly progressive glomerulonephritis (RPGN) due to MPO-ANCA and anti-GBM associated renal disease. The patient was started on prednisolone and double filtration plasmapheresis (DFPP) therapy. Subsequently, the values of MPO-ANCA and AGBMA decreased. However, the patient's condition suddenly worsened and she died of interstitial pneumonia. Autopsy examination revealed crescentic glomerulonephritis and alveolar hemorrhage with linear deposition of IgG along the glomerular and alveolar capillary walls by immunofluorescence studies. We considered this to be a rare case of Goodpasture's syndrome associated with not only anti-GBM antibodies, but also MPO-ANCA.

Assessment of topogenic functions of anticipated transmembrane segments of human band 3

Band 3 protein is a typical multispanning membrane protein whose membrane topology has been extensively studied from various protein chemical approaches. To clarify the membrane topogenesis of this multispanning protein on the endoplasmic reticulum, the topogenic functions of the anticipated transmembrane segments were individually assessed in an in vitro system using two series of model proteins in which each segment was placed in either a "stop-transfer" context or a "translocation initiation" context. They were expressed in a cell-free system containing rough microsomal membranes, and their topologies were evaluated by taking advantage of either sensitivity to protease or accessibility to N-glycosylation. We found that some segments seem to possess insufficient topogenic functions for membrane integration: the second transmembrane segment (TM2) is insufficient for the stop-transfer sequence, and TM3, TM5, and TM7 are not sufficient for the translocation initiation. In contrast to these phenomena, we herein demonstrate that TM2 shows an efficient stop-transfer function when it is near the preceding TM1 and suggest that TM3, TM5, and TM7 are followed by TM segments with a strong topogenic function to form Nexo/Ccyt topology, via which the preceding segments are integrated into the membrane. From these results, we propose that the interactions between the TMs should be operative during membrane integration, and that the segments with a weak topogenic function are given a transmembrane orientation by their following TMs.

Forced transmembrane orientation of hydrophilic polypeptide segments in multispanning membrane proteins

In a current model of integration of multispanning membrane proteins into the endoplasmic reticulum, it is proposed that the transmembrane segments show alternating translocation initiation and stop-transfer functions. Here, we present evidence for a mode of cotranslational insertion in which an internal signal-anchor sequence with Nexo/Ccyt topology confers a transmembrane disposition onto a preceding hydrophilic segment, resulting in a topology where the hydrophilic segment apparently can slip back and forth across the membrane. Our results demonstrate that hydrophobicity is not, as hitherto thought, an absolute requirement for the formation of a transmembrane segment, and suggest that integral membrane proteins may contain hydrophilic transmembrane segments with a considerable freedom to move in relation to the membrane.

[Role of superoxide generation and degradation system of mast cells in allergic inflammation]

Rat peritoneal mast cells are stimulated to generate superoxide anion (O2) by the addition of compound 48/80 and A23187. Recently, we demonstrated by immunohistochemical and Western blot analysis that the mast cells contained the p47phox protein, which was one of cytosolic component of the NADPH oxidase system. In the present study, it was demonstrated that the mast cells contained the p47phox mRNA, much similar to that of mouse leukocyte. The permeabilized mast cells were stimulated to generate O2- by the addition of Ca2+, phospholipase A2 (PLA2) and arachidonic acid. Our data suggest the following:(1) cytosolic PLA2 may be activated by the elevation of [Ca2+]i; (2) the conjugation of membrane component with cytosolic component may be stimulated by the released arachidonic acid. The mast cell granules contained superoxide dismutase (SOD)-like enzyme, which degradated O2-, generated in xanthine-xanthinoxidase system. SOD-like enzyme was released from the granules by the treatment with Ca2+ and trapped by the treatment with heparin. In conclusion, our studies suggest that the disorder of the degradation system of O2- may contribute to the development of allergic inflammation.

Characterization of the initial steps of precursor import into rat liver mitoplasts

Mitochondria have two independent protein-import machineries, one in the outer membrane (the Tom system) and the other in the inner membrane (the Tim system). Here, we have characterized the initial steps of precursor import into rat liver mitoplasts. The import reaction was separated into two stages, consisting of precursor binding to the mitoplasts at 0-10 degreesC, and a subsequent chase reaction at 30 degreesC. This assay revealed four distinct precursor-import steps: DeltaPsi-dependent initial binding of the precursor, precursor transfer to the Tim23-Tim17 stage, DeltaPsi-dependent translocation of the presequence across the inner membrane, and the complete translocation of the mature portion of the precursor. Antibodies against the intermembrane space domain of Tim23 inhibited neither the precursor binding nor the subsequent translocation of the presequence across the inner membrane. In contrast, the antibodies inhibited the complete translocation of the mature domain of the precursor across the inner membrane. Immunoprecipitation with anti-Tim23 IgGs revealed that the precursor-Tim23 complex increased with time and temperature after the initial targeting of the precursor to the mitoplasts. These results suggest that the precursor is first targeted to the inner membrane component DeltaPsi-dependently, then transferred to the Tim system consisting of Tim23-Tim17, and finally imported into the matrix.

Beta-casomorphin-5 stimulates neurite outgrowth in a mouse neuroblastoma cell line (Neuro-2a)

We studied the effect of beta-casomorphin-5 (mu-acting opioid peptides derived from milk protein beta-casein) on neurite outgrowth of mouse neuroblastoma cell line, Neuro-2a. Beta-casomorphin-5 stimulated neurite outgrowth of Neuro-2a cells in a naloxone-reversible manner. The stimulating effect of beta-casomorphin-5 was observed even at picomolar concentrations. The selective mu-agonist, (D-Ala2, N-Me-Phe4, Gly5-ol)-enkephalin (DAMGO) exhibited the similar stimulating effect only at micromolar concentrations. On the other hand, (D-Pen(2,5))-enkephalin (DPDPE) (a delta-agonist), U-50,488 (a kappa-agonist), and endogenous opioid peptides, such as enkephalins and dynorphin A (1-13), showed no such stimulating effect. These results suggest that the neurite outgrowth-stimulating action of beta-casomorphin-5 may be mediated via a receptor which has mu-like characteristics and high sensitivity to beta-casomorphin-5, and that beta-casomorphins may play a role as a neurite elongation factor during the suckling period.

Characteristics of intracellular transferrin produced by human fibroblasts: its posttranscriptional regulation and association with tubulin

Transferrin (Tf), an iron-binding protein, was investigated in the cultured human fibroblast which is a major cell type in connective tissues. Tf is a major iron-transporting protein and has an important role in iron metabolism. Using two-dimensional gel electrophoresis, we demonstrated the eight subtypes of Tf produced by cultured normal human fibroblasts and their down-regulation after the immortalization of human cells, an essential early step of in vitro transformation. However, the amount of Tf mRNA in the immortalized cells was equal to that in the normal human fibroblasts, suggesting that the down-regulation occurred at the posttranscriptional level. The amount of Tf receptor increased in the immortalized cells in spite of a decrease in the amount of intracellular Tf. Interestingly the produced Tf associated with microtubules. These findings suggest a novel aspect of Tf characteristics in human fibroblasts.

Two-dimensional gel electrophoretic analysis of the changes after immortalization of human cells: decrease of intracellular alpha-2-macroglobulin fragment

To study the mechanisms of immortalization of human cells, an early step in cancer development, we compared the cellular proteins of normal and immortalized human fibroblasts. Two-dimensional gel electrophoresis showed that one spot with a molecular mass 20 kDa and an isoelectric point of 6.0, became significantly smaller after immortalization of human cells. Further, the spot was rarely observed in four human liver cancer cell lines. Investigation of the N-terminal amino acids revealed that the spot was a fragment of alpha-2-macroglobulin. Although the 20 kDa fragment contains methionine, the spot was not labeled with [35S]methionine. Thus we concluded that the spot might be derived from the culture medium. These results indicated that intracellular metabolism of a-2-macroglobulin, which is a multifunctional protease inhibitor, changed after the cells were transformed.

Cases of systemic immediate-type urticaria associated with acellular diphtheria-tetanus-pertussis vaccination

The authors found eight children who had systemic urticaria within 30 min after administration of acellular diphtheria-tetanus-pertussis (DTP) vaccines which contain gelatin as a stabilizer. The authors measured the specific IgE to gelatin and DTP toxoids in their sera, and found that none of the children had anti-gelatin IgE. Of the eight children, two had detectable levels of anti-toxoid IgE. As a negative control, of the 10 children who showed no allergic reaction to the acellular DTP vaccines, four also had detectable levels of anti-toxoid IgE. From these results, there was no obvious relationship between the specific IgE to the vaccine's component proteins and systemic urticaria to acellular DTP vaccines.

Cytokine production by T cells infiltrating in the eye of uveitis patients

The capacity of T cells to produce cytokines was investigated using T-cell clones (TCCs) established from infiltrating cells in the aqueous humor (AH) or peripheral blood mononuclear cells (PBMC) of patients with Vogt-Koyanagi-Harada (VKH) disease or sarcoidosis. The cytokines produced and tested in the study were interleukin (IL)-1alpha, IL-6, IL-8, interferon (IFN)-gamma, tumor necrosis factor (TNF)-alpha, and granulocyte monocyte colony stimulating factor (GM-CSF). All TCCs (n = 9) from AH of VKH patients spontaneously produced significantly larger amounts of IL-6, IL-8, and IFN-gamma than TCCs from healthy donor PBMC. All TCCs (n = 9) from AH of the sarcoidosis patient spontaneously produced significantly larger amounts of IL-1alpha, IL-6, and IL-8 than TCCs from healthy donor PBMC. In addition, the effects of antiinflammatory drugs on the cytokine production by the TCCs were investigated. Hydrocortisone significantly suppressed the production of IL-6, IL-8, and GM-CSF by TCCs from AH of VKH patients. Tacrolimus also significantly suppressed the production of IL-8 and GM-CSF by the TCCs. FTY720, an experimental drug, suppressed only GM-CSF production by TCCs from AH of VKH patients. Diclofenac failed to suppress the production of any cytokines by any TCCs. All tested drugs did not suppress the production of cytokines by TCCs from the sarcoidosis patient. These results thus suggest that cytokines produced by T cells infiltrating in the eye may play an important role in the pathogenesis of uveitis.

Thiol compounds rescue growth inhibition by retinoic acid on HTLV-I (+) T lymphocytes; possible mechanism of retinoic-acid-induced growth inhibition of adult T-cell leukemia cells

We demonstrated significant growth inhibition by retinoic acid (RA) of HTLV-I (+) T-cell lines (ATL-2 and HUT102), but not HTLV-I (-) T-cell lines (MOLT-4 and Jurkat). We hypothesized that the mechanism of growth inhibition by RA depends on an imbalance in redox potential. To examine the effect of exogenous thiol compounds for the growth of HTLV-I (+) T-cell lines by RA, HTLV-I (+) T-cell lines were cultured with several thiol compounds (thioredoxin, L-cystine, and GSH), following addition of 13-cis RA or ATRA, respectively, in cultured with thiol free medium. Unexpectedly, thiol compounds alone did not restore growth inhibition of HTLV-I (+) T-cell lines. However, when those cells were preincubated with thiol compounds for 24 hours, no growth inhibition by 13-cis RA or ATRA was observed. These results suggest that thiol compounds are associated strongly with sensitivity to RA of HTLV-I (+) T cells, but not of HTLV-I (-) T cells and that thiol compounds serve an important role on HTLV-I (+) T cells.

Existence of two isoforms of extracellular signal-regulated kinase in fish

Full-length cDNAs for extracellular signal-regulated kinases (ERK1 and ERK2) were isolated from a carp ovary cDNA library. The deduced amino acid sequences of carp ERK1 (cERK1) and ERK2 (cERK2) exhibited high degrees of homology to the known sequences of the ERK group. Northern blot analysis showed that cERK1 mRNA was not expressed in a tissue-specific manner, though the level of expression of cERK2 mRNA varied among tissues. Western blot analysis of the brain, kidney, and ovary confirmed the expression of cERK1 and cERK2 in carp. Our findings indicate that two isoforms of ERK, ERK1 and ERK2, exist in fish.