Effect of simultaneous infusion of donor bone marrow on hamster-to-rat heart xenograft survival.
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Biomedical subjects
Publications and source records attributed to S Yoshioka.
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The protein stability of lyophilized serum gamma-globulin (BGG) formulations containing poly(vinyl alcohol) (PVA) and dextran was studied in relation to the molecular mobility as determined by proton NMR. The critical temperature, Tmc, at which the Lorentzian relaxation process due to liquid polymer protons appears in these lyophilized formulations was lower than the glass transition temperature, Tg. Above Tmc, protein aggregation in the formulations was related to the Tmc according to the Williams-Landel-Ferry equation by replacing Tg with Tmc. Protein aggregation appears to occur substantially in a "rubbery-like" state even below Tg, if the formulations become microscopically liquidized above Tmc. Lyophilized BGG formulations containing PVA with a lower water content were less stable than those containing dextran with a higher water content. The difference in stability can be explained by the difference in the Tmc of these formulations. Tmc that is determined by NMR relaxation measurement appears to be a useful parameter for the characterization of protein formulations, for which the Tg cannot generally be determined by standard calorimetric techniques. Furthermore, Tmc appears to be more closely related to protein stability than does Tg.
OBJECTIVE: To examine the expression of peroxisome proliferator-activated receptor gamma (PPARgamma) together with CCAAT/enhancer binding protein alpha (C/EBPalpha), lipoprotein lipase (LPL) and glucose transporter (GLUT4) mRNA in adipose tissue of rhesus monkeys in relation to obesity. DESIGN: Cloning of the PPARgamma1 and gamma2 cDNAs and analysis of PPARgamma, C/EBPalpha, LPL and GLUT4 mRNA levels in the adipose tissue of lean and obese monkeys. SUBJECTS: 28 rhesus monkeys (Macaca mulatta) with a wide range of body weights (9.2-22.6 kg) and with or without type 2 diabetes. MEASUREMENTS: Sequence of PPARgamma1 and gamma2. Tissue distribution of PPARgamma1 and gamma2. The mRNA levels of PPARgamma, C/EBPalpha, LPL and GLUT4 in adipose tissue. The ratio of PPARgamma2 mRNA to total PPARgamma mRNA. RESULTS: The monkey PPARgamma2 protein showed 99% identity with the human protein. PPARgamma1 mRNA was shown to be expressed in various tissues and most abundantly in adipose tissue. PPARgamma2 existed mainly in adipose tissue. A significant correlation between the ratio of PPARgamma2 mRNA to total PPARgamma mRNA and obesity was observed, whereas total PPARgamma mRNA levels showed no significant relationships to obesity. There was also a significant relationship between the ratio of PPARgamma2 mRNA to total PPARgamma mRNA and fasting plasma insulin concentration. The mRNA levels of C/EBPalpha, LPL and GLUT4 were highly correlated to that of total PPARgamma mRNA. They were also significantly correlated to the mRNA levels of PPARgamma1 and PPARgamma2. CONCLUSIONS: The ratio of PPARgamma2 mRNA to total PPARgamma mRNA is related to obesity in the rhesus monkey and mRNA expression of PPARgamma1, PPARgamma2, C/EBPalpha, LPL and GLUT4 appear to be coordinated in vivo.
The aim of this study was to further assess the role of pooled human immunoglobulin (PHIG) on cytokine production from PBMC stimulated with a bacterial superantigen. Human PBMC were cultured with Streptococcus pyrogenic exotoxin A (SPE-A) with or without PHIG and several proinflammatory cytokine levels of culture supernatants were measured. Serum cytokine levels of KD patients before and after PHIG therapy were also examined. PHIG greatly reduced the production of IL-12, interferon-gamma (IFN-gamma) and other cytokines from SPE-A-stimulated PBMC, while exogenous IL-12, but neither IL-1 nor tumour necrosis factor-alpha (TNF-alpha), restored IFN-gamma production inhibited by PHIG. Although PHIG partially adsorbed SPE-A, its inhibitory effect on cytokine production was not played by anti-SPE-A antibody. Although purified CD4+ T cells cultured with human HLA-DR-transfected mouse L cells and SPE-A could not effectively produce IFN-gamma, they produced large amounts of IFN-gamma if exogenous IL-12 was introduced. KD patients in the acute phase had higher levels of serum IFN-gamma than did controls and patients with bacterial infection. Although IL-12 levels of children with or without KD were not significantly different, IL-12 levels of children were much higher than those of adults. However, serum levels of IL-12 of KD patients were transiently but significantly decreased by PHIG therapy and IFN-gamma amounts subsequently reverted to basal levels thereafter. These findings indicate that PHIG inhibits IL-12 production of SPE-A-activated monocytes and thereby decreases IFN-gamma synthesis by T cells and suggest that inhibition of IL-12 and IFN-gamma production is an important part of the mechanisms underlying PHIG therapy on KD.
Human luteal cells have been reported to express human leukocyte antigen-DR and lymphocyte functional antigen-3 on the cell surface, suggesting physiological interaction between luteal cells and T-lymphocytes through the menstrual cycle into early pregnancy. To elucidate the role of peripheral lymphocytes on corpus luteum differentiation, the effect of peripheral blood mononuclear cells (PBMC) on steroidogenesis by luteal cells was investigated. The production of Th-2 cytokines such as interleukin (IL)-4 and IL-10 by the co-cultured cells was also examined, and the effects of these cytokines on progesterone production by luteal cells were investigated. Corpora lutea were obtained from eight non-pregnant women in the luteal phase and five women in early pregnancy for luteal cell culture. PBMC were isolated from unrelated women in the follicular phase, secretory phase, and early pregnancy. After coculture with allogenic PBMC for 48 h, progesterone production was significantly enhanced by PBMC from the secretory phase and early pregnancy in the non-pregnant luteal cell culture. In the pregnant luteal cell culture, a significant increase in progesterone production was also observed by the co-culture with PBMC from women in early pregnancy, showing that PBMC have a luteotrophic effect. The stimulatory effects of PBMC were also observed in co-culture conditions which prevented direct cell-to-cell interaction with luteal cells, showing the minor influence of mixed lymphocyte reaction. By co-culture with PBMC, the production of IL-10, but not IL-4, was significantly augmented in luteal cell culture derived from non-pregnant women, whereas the production of both IL-4 and IL-10 was significantly enhanced in the luteal cell culture derived from pregnant women. Moreover, IL-4 and IL-10 promoted progesterone production by cultured luteal cells, especially in the luteal cell culture derived from corpora lutea of early pregnancy. These findings indicate that PBMC stimulate progesterone production by luteal cells and suggest the involvement of PBMC in corpus luteum function and differentiation probably via the Th-2-type lymphocytes.
We have previously reported that membrane-bound aminopeptidases were expressed on human follicles and corpora lutea (CL) and we showed that these aminopeptidases are involved in follicular growth, probably by regulating extracellular peptide concentrations. In this study, the expression of membrane-bound carboxypeptidase-M (CP-M), which cleaves carboxyl-terminal amino acids from peptides extracellularly, on human follicles and CL was examined. In growing and pre-ovulatory follicles, CP-M was immunohistochemically detected with weak or moderate intensity on theca interna cells. Although CP-M was not detected on granulosa cells in growing and pre-ovulatory follicles, it was strongly detected on the cell surface of luteinizing granulosa cells isolated from patients undergoing in-vitro fertilization treatment, indicating that CP-M was rapidly expressed on granulosa cells during ovulation. In menstrual and pregnant CL, CP-M was clearly detected on luteal cells. In menstrual CL, the expression of CP-M mRNA was observed by reverse transcription-polymerase chain reaction (RT-PCR). Western blotting analysis revealed that the molecular mass of the CP-M extracted from mid-luteal CL was 62 kDa. These results indicate that CP-M is a cell surface differentiation-related molecule of human granulosa, theca, and luteal cells. The rapid expression on granulosa cells during ovulation strongly suggests the involvement of CP-M in the ovulation and CL formation processes.
Leukotriene (LT) A4 hydrolase (EC3.3.2.6) converts LTA4 to LTB4 which shows a chemotactic activity to leukocytes. To investigate the involvement of LTB4 in human corpus luteum (CL) function, the localization of LTA4 hydrolase in human ovarian tissues was examined by immunohistochemistry with a rabbit polyclonal antibody against LTA4 hydrolase. The enzyme was weakly expressed on granulosa cells of the follicles. After ovulation, the intensity of LTA4 hydrolase on large luteal cells increased and was highest in the midluteal phase. High expression was also observed in the CL of early pregnancy. In theca interna and small luteal cells, LTA4 hydrolase was weakly detected in all developmental stages. Immunoblot analysis demonstrated that the molecular mass of LTA4 hydrolase expressed in CL was 62 kDa, and confirmed that LTA4 hydrolase expression increased during CL formation and remained high in early pregnancy. The sequence encoding mRNA of LTA4 hydrolase, which was isolated from CL and amplified by polymerase chain reaction, was shown to be identical to the previously reported one. Immunocytochemistry showed that LTA4 hydrolase expression in cultured granulosa cells increased over 4 days in vitro and was enhanced by human chorionic gonadotrophin treatment. These expression profiles of LTA4 hydrolase suggest the involvement of LTB4 in luteal cell function during CL formation and early pregnancy.
Nucleotide sugar transporters are mainly located in the Golgi membranes and carry nucleotide sugars, that are produced outside the Golgi apparatus, into the organelle, where they serve as substrates for the elongation of carbohydrate chains by glycosyltransferases. They are thus indispensable for cellular glycoconjugate synthesis and, moreover, may have regulatory roles in producing the structural variety of cellular glycoconjugates. Their occurrence has long been well recognized, but studies on the molecular bases of their strict substrate specificities and modes of action have been hampered by the lack of information on their precise molecular structures. Complementary DNAs encoding several of these transporters were cloned recently, which represented a substantial step forward as to the above mentioned issues. The products of these cDNAs are mutually related hydrophobic proteins consisting of 320-400 amino acid residues with multiple putative transmembrane helix domains, and are located in the Golgi apparatus. This review briefly summarizes the present status of the field of nucleotide sugar transporter research, and also presents an outlook of the study in this field.
We describe the functional expression of the putative human Golgi UDP-galactose transporters (hUGT1 and hUGT2) in the yeast Saccharomyces cerevisiae. Both hUGT1 and hUGT2 were expressed under the control of the yeast constitutive GAPDH promoter. The expression level of hUGT1 seemed to be considerably lower than that of hUGT2, although hUGT1 has an amino acid sequence identical to that of hUGT2 except for 5 amino acid residues at the C-terminus. The hUGT product was expressed in the membranes of Golgi and other organellar compartments. The membrane vesicles prepared from the hUGT1- or the hUGT2-expressing yeast cells exhibited UDP-galactose specific transport activity. The apparent Km values of the yeast-expressed hUGT1 and hUGT2 for UDP-galactose were 1.2 and 2 microM, respectively, which were comparable with the Km obtained with mammalian Golgi vesicles. Transport was dependent on temperature and integrity of vesicles, and was inhibited by UMP, as observed with mammalian Golgi vesicles. Our results demonstrate that the previously described hUGT1 and hUGT2 encode the UDP-galactose transporters, rather than regulatory proteins. The development of a convenient yeast expression system should facilitate analysis of the structure-function relationships of the UDP-galactose transporters.
We recently described the cloning of putative human CMP-sialic acid transporter (hCST) cDNA [Ishida, N. et al. (1996) J. Biochem. 120, 1074-1078]. The hCST cDNA coded for a hydrophobic protein with an amino acid sequence showing a high degree of similarity (92% identity) to that of murine CMP-sialic acid transporter. In this report, we demonstrate that hCST corrects the CMP-sialic acid transporter-deficient phenotype of CHO-derived Lec2 cells, as judged from the recovery of WGA-sensitivity by transformants, and the recovery of CMP-sialic acid transporting ability by microsomal vesicles prepared from them. A peptide antibody against the C-terminus of the hCST protein detected the cDNA products expressed in the microsomes of the transformants. The subcellular localization of the hCST protein in the Golgi membrane was demonstrated by immunofluorescence microscopy, using the hCST-specific antibody. These results clearly indicate that hCST cDNA encodes the human CMP-sialic acid transporter protein. Plasma membrane-selective permeabilization combined with immunofluorescence microscopy provided strong evidence that the C-terminus of the human CMP-Sia transporter is exposed to the cytosol on the outer surface of the Golgi membrane.
Cerebral SPECT imaging has the potential to make important contributions in the follow-up care of patients with Alzheimer's disease. An unusual case of a patient who showed a follow-up cerebral blood flow pattern different from that routinely seen in Alzheimer's disease patients is reported here. Qualitative and voxel-based objective evaluation of follow-up scans revealed improvement in parietotemporal deficits that had been observed on a baseline study. This change was observed without significant further deterioration in ratings by dementia batteries. This case shows that a baseline regional cerebral blood flow study might be necessary for reference and comparison in the proper follow-up care of Alzheimer's disease patients.
(1 --> 3)-Beta-D-Glucan (beta-glucan) is a biological response modifier that regulates host immune response. However, the side effects of this drug have not been extensively examined. In this study, we found that the combination of a beta-glucan and a nonsteroidal anti-inflammatory drug, indomethacin, induced lethal toxicity in mice. Lethal toxicity of orally administered indomethacin (multiple administration to ICR mice; once a day for 2 weeks) was 0/8 (2.5 mg kg(-1)) and 5/8 (5 mg kg(-1)) (death/total) over 2 weeks. The toxicity was enhanced to 3/8 and 8/8 in mice treated with a clinical beta-glucan preparation, sonifilan (250 microg/mouse, single i.p. administration on day 0). A similar effect was observed for other beta-glucans, including SSG, grifolan, zymosan A and zymocel. Enhanced lethal toxicity resulted from a single p.o. administration of indomethacin on day 5 to day 9 after multiple beta-glucans administration. Interferon-gamma, interleukin-6 and colony stimulating factor concentrations in sera of indomethacin/beta-glucan-treated mice were significantly elevated. These results strongly suggest that indomethacin/beta-glucan treatment induces lethality in mice by maladjusting the cytokine network.
We have previously reported that membrane-bound amino- and carboxypeptidases were expressed on the human follicles and corpora lutea (CL), and we proposed that these peptidases are involved in ovarian functions, probably by regulating the extracellular peptide concentrations. In this study, we examined the expression of endothelin-converting enzyme-1 (ECE-1) on human follicles and CL, which is a membrane-bound endopeptidase and is known to convert big endothelin-1 to endothelin-1. In the preovulatory follicles, immunohistochemical study showed that ECE-1 was expressed, with moderate intensity, on the theca interna cells and weakly on the granulosa cells. In the menstrual and pregnant CL, ECE-1 was highly expressed on both large and small luteal cells, indicating that ECE-1 expression increases during luteinization. Western blotting analysis revealed that the molecular mass of the ECE-1 extracted from the menstrual CL was 130 kDa and that ECE-1 was more strongly expressed on the CL in early and midluteal phases than the CL in late luteal phases. In the isolated luteinizing granulosa cells obtained from patients undergoing in vitro fertilization, ECE-1 was immunohistochemically detected on their cell surface. The activity of ECE-1 was also detected on cultured luteinizing granulosa cells by measuring endothelin-1 production from its precursor. The activity of ECE-1 was significantly enhanced by the treatment of human CG (10 U/mL) and interleukin (IL)-1 (10 ng/mL) during 4-day culture, whereas no significant alteration was observed by IL-4 (10 ng/mL) and IL-10 (10 ng/mL) treatment. These results indicate that ECE-1 is a cell surface differentiation-related molecule of human granulosa and of theca interna cells and suggest that the expression of ECE-1 is regulated by LH/human CG and cytokines.
Crosslinked dextran hydrogels were prepared from glycidyl methacrylate (GMA)-derivatized dextran by gamma-irradiation initiation in the presence of insulin and lysozyme as model protein and peptide drugs. The diffusion coefficient of insulin and lysozyme in the hydrogels was determined successfully by a pulsed-field-gradient stimulated-echo method. A conventional NMR probe which can impose a relatively small magnetic field gradient (30 Gauss/cm) was used for the measurements. This method seems to be applicable to proteins and peptides with a molecular weight of about 10,000 or less. The diffusion coefficient determined by the NMR method almost agreed with that calculated from the drug release profiles, indicating the usefulness of the diffusion coefficient determined by the NMR method as a measure of the release rate from hydrogels.
The evgAS operon of Escherichia coli encodes the EvgA response regulator and the EvgS sensory kinase, which are members of one of the two-component signal transduction systems of Escherichia coli. In this study, we identified the evg promoter and the EvgA-responsive element. Primer extension analysis found two evg transcriptional initiation sites, designated P1 (+1) and P2 (-10), and placed them 114 bp and 124 bp upstream of evgA, respectively. A gel retardation assay demonstrated that EvgA specifically bound to an inverted repeat located between -102 and -128 counting from P1. We also did a beta-galactosidase induction experiment using a promoter-probing vector and found that the EvgA-binding sequence was important to stimulate the evg promoter. These results suggest that the expression of evgAS is positively regulated by its own product, EvgA.
We have isolated from Thermus aquaticus an insertion-sequence-like genetic element (ISLtaq1) that induces thermotolerance and has a high sequence similarity to IS150 belonging to the IS3 family. An open reading frame on ISLtaq1, termed ORF1, encodes the ORF1 protein, which carries a DNA-binding motif. In this study, we found an imperfect inverted repeat in ISLtaq1. We next overproduced and purified a His-tagged ORF1 protein. Gel retardation analysis demonstrated that this protein specifically bound to an DNA fragment containing the inverted repeat in ISLtaq1. These results suggest that ISLtaq1 and the ORF1 protein are an insertion sequence and part of the transposase encoded by ISLtaq1, respectively.
EvgA and EvgS constitute one two-component signal transduction system in Escherichia coli. Although probable signaling domains of these proteins have been estimated, the molecular mechanism of their interaction remains to be elucidated. Here, we investigated protein to protein interactions between EvgA and EvgS and also between the EvgAS system and other related signaling pathways by means of surface plasmon resonance. EvgA and EvgS interacted directly and inhibition of phosphorylation of their functional domains abolished formation of the EvgAS complex. No interaction was observed either between EvgA and Bordetella BvgS or BvgA and EvgS. OmpR, a response regulator for the osmoregulative gene expression of E. coli, had similar but not identical behavior towards EvgS to that of EvgA. These results indicate that interaction between the signaling proteins is closely related to phosphorylation of the functional domain of the proteins.