Induction of an endogenous tumor necrosis factor in mice by murine recombinant interferon-γ combined with a lipid A subunit analog (GLA-60) of low toxicity

Summary We have investigated the endogenous production of a serum cytotoxic factor when recombinant interferon- (rIFN-) is combined with synthetic lipid A subunit analogs of low toxicity (GLA compounds). The cytotoxic activity of the serum was measured by the crystal violet staining method with L929 cells as a target. Intravenous administration of rIFN- followed by intravenous administration of lipopolysaccharide induced the endogenous production of a cytotoxic factor in the serum. The priming effect of rIFN- appeared immediately and persisted for approximately 20 h after the injection. Administration of lipopolysaccharide as a trigger enhanced the production of the cytotoxic factor in the serum maximally 2 h after the injection. The cytotoxic activity in the serum was completely inhibited by anti-(mouse tumor necrosis factor) (TNF) antibody. A synthetic lipid A subunit analog (GLA-60), which is much less toxic in its endotoxin activities than lipopolysaccharide or synthetic lipid A (compound 506), induced the endogenous production of serum TNF in rIFN--primed mice. GLA-60 entrapped within liposomes induced the production of serum TNF in rIFN--primed mice more effectively than GLA-60 solubilized in phosphate-buffered saline. Intravenous or intranasal administrations of rIFN- followed by intranasal administration of GLA-60 produced TNF in the lung washing fluid but not in the serum, indicating that TNF production can be induced locally rather than systemically by the alteration of the administration route of the primer and trigger. These results indicate that GLA-60, a lipid A subunit analog of low toxicity, is a beneficial triggering agent in the production of endogenous TNF, as well as having other immunopharmacological properties, and may provide a basis for cancer (metastases) treatment as a result of its ability to induce endogenous TNF.     

Screening test for deodorizing substances from marine algae and identification of phlorotannins as the effective ingredients in Eisenia bicyclis

Aqueous extracts from 33 species of marine algae were assessed for their methyl mercaptan-trapping activity by gas chromatography to search for novel natural oral deodorants. Brown algae belonging to the Laminariales such as Eisenia bicyclis, Ecklonia cava and Ecklonia kurome were found to show remarkable deodorizing action against methyl mercaptan. The effective components in Eisenia bicyclis were identified as a phlorotannin, a group of molecules which are characteristic components of Laminariales. In addition phlorotannins extracted from E. bicyclis were more effective at reducing methyl mercaptan than conventional natural deodorants such as chlorophyll and sodium copper chlorophyllin.Author for Correspondence     

Regional localization of a trophoblast antigen-related sequence and 16 other sequences to human chromosomes 6q using somatic cell hybrids.

Using a panel of 13 hybrid cell lines, we have regionally localized 22 markers to the long arm of chromosome 6. Revised or new locations are provided for 17 of the markers, and preliminary assignments to chromosome 6 of 11 loci are confirmed. The location of NT5, previously determined by antigen expression in hybrids, has been confirmed at 6q14-q15 by using a cDNA probe. Other DNA probes include one new anonymous sequence, designated D6S130, that maps to 6q12 and 4 VNTR probes that map to the proterminal band, 6q27. Probe CRI-L1065 also maps to 6q21, CRI-994 maps to 6q21-qter, and CRI-L322 maps to 6q14-15, information that may assist the merging of physical and genetic maps.     

Melanin-concentrating hormone-like immunoreactive material in the rat hypothalamus; characterization and subcellular localization

Summary Melanin-concentrating hormone (MCH) is a neurosecretory peptide that induces melanin concentration within teleost melanophores. Here, we characterized MCH-like substance in the rat brain by both an in vitro fish-scale melanophore bioassay and a radioimmunoassay with a salmon MCH antiserum that is directed toward the carboxy-terminus and requires the cyclic configuration for recognition. Furthermore, subcellular localization of the MCH in the rat brain was examined by immunocytochemistry using electron microscopy. We confirmed that MCH-immunoreactivity and MCH-bioactivity were present together in the same effluent fractions of the rat hypothalamic extracts by reverse-phase high-performance liquid chromatography (HPLC). At electron microscopic level, MCH-immunoreactivity was located specifically in secretory granules in MCH-positive cell bodies confined to the hypothalamus with their neuronal processes projecting widely in the rat brain. Although full characterization of substance must await its isolation, our results strongly support the notion that rat MCH-like substance may be homologous but not identical to salmon MCH, and simultaneously may serve some neurotransmitter and/or neuromodulator role in the brain of the rat.     

Maple syrup urine disease: a possible biochemical basis for the clinical heterogeneity

Summary Nine patients with maple syrup urine disease (MSUD), of whom eight were detected by mass-screening of neonates for inherited metabolic desease, were studied to determine possible relationships between clinical features and properties of the branched-chain -keto acid dehydrogenase complex (BCKDH) in cultured lymphoblastoid cells. Based on their tolerance for leucine and on the clinical manifestations observed after 2 years of age, most could be classified into three types; classical (tolerate less than 600 mg of leucine per day, N=2), intermediate (N=3) and intermittent (N=3) types. In the other patient two of these three phenotypes were present. The BCKDH activities measured at a lower -ketoisovaleric acid concentration (0.054 mM) were 0.026±0.015 in classical, 0.118±0.016 in intermediate and 0.625±0.139 in intermittent types and 7.052±0.779 (nmol/h per milligram of protein) in two controls, respectively; the differences being statistically significant (P<0.01, classical vs intermediate types; P<0.01, intermediate vs intermittent types; P<0.01, intermittent vs control). Kinetic and immunochemical analyses of the BCKDH revealed that, although there are a few exceptions, classical, intermediate and intermittent types correspond to the enzyme properties of sigmoidal kinetics with E₁ subunit deficiency, near-sigmoidal kinetics with E₁ subunit deficiency and hyperbolic kinetics with E₂ subunit deficiency of the BCKDH, respectively.     

Endemic impact of human T cell leukemia virus type 1 screening in bone allografts

Allograft bone is a widely used as a convenient tool for reconstructing massive bone defects in orthopedic surgery. However, allografts are associated with the risk of viral disease transmission. One of the viruses transmitted in this manner is human T-lymphotropic virus type 1 (HTLV-1), which is found worldwide but is unevenly distributed. The southwestern parts of Japan are a highly endemic for HTLV-1. We investigated the HTLV-1 seroprevalence in candidate allograft donors at the regional bone bank in Kagoshima, Japan during its first 5 years of service. Between 2008 and 2012, we collected 282 femoral heads at the Kagoshima regional bone bank from living donors with osteoarthritis of the hip joint. Among the 282 candidate donors, 32 donors (11.3 %) were seropositive for anti-HTLV-1 antibody; notably, this prevalence is higher than that reported for blood donors in this area. Additionally, to determine if HTLV-1 genes are detectable after processing, we examined the bone marrow of the femoral heads from seropositive donors by conducting PCR assays. Our results confirm the existence of viral genes following the heat treatment processing of the femoral heads. Therefore, it is important to inactivate a virus completely by heat-treatment. Together, our findings highlight the importance of HTLV-1 screening at bone banks, particularly in HTLV-1-endemic areas such as southwest Japan.     

Ca2+ Regulation of Outward Rectifying K+ Channel in the Plasma Membrane of Tobacco Cultured Cells in Suspension: a Role of the K +Channel in Mitigation of Salt-Stress Effects by External Ca2+

The patch-clamp technique was used to study effect of the Ca²⁺on K⁺ channels in the plasma membrane of protoplasts isolatedfrom tobacco (Nicotiana tabacum L., cv. Bright Yellow) culturedcells in suspension. The outward rectifying whole-cell K⁺ currentswere not affected by in-tracellular Ca²⁺, but they were reducedwith increasing extracellular Ca²⁺. Neither extracellular norintracellular Ca²⁺ affected the permeability ratios (p_K+/P_Na+)of the plasma membrane. These results suggest that the inhibitionof outward-rectifying K⁺ channels by extracellular Ca²⁺may partiallycontribute towards the mitigation of detrimental effects ofsalinity on growth by extracellular Ca²⁺. (Received January 19, 1998; Accepted July 30, 1998)