Isolation and characterization of an immunosuppressive acidic protein from ascitic fluids of cancer patients

Analytical isoelectric focusing in polyacrylamide gel at pH 2.5 to pH 5 was used successfully to detect an acidic protein which can be found in large quantities in the sera of cancer patients but in only small amounts in the sera of healthy persons. The main peak of this acidic protein when obtained from cancer patients revealed a pI of 3.0, while the pI of that obtained from normal subjects was 3.1. The results obtained also demonstrated that qualitative and quantitative differences of such serum acidic proteins discriminate between sera of normal persons and cancer patients. Purification of this acidic protein (pI 3.0) was attempted with cancer ascitic fluids by successive ammonium sulfate precipitation, diethylaminoethyl cellulose column chromatography, Sephadex G-100 gel filtration, and preparative isoelectric focusing. When the purified acidic protein was characterized for physicochemical properties, it was found to have an isoelectric point of 3.0, to have a molecular weight of 50,000, and to contain 31.5% carbohydrate. Its behavior in immunodiffusion and immunoelectrophoresis was indistinguishable from that of normal human alpha 1-acid glycoprotein. However, in gel isoelectric focusing, in molecular weight, and also in carbohydrate content, the acidic protein isolated from cancer ascitic fluid differed from normal alpha 1-acid glycoprotein. Furthermore, this acidic protein was found to suppress both phytohemagglutinin-induced lymphocyte blast formation and mixed-lymphocytes reaction in vitro. The acidic protein, which we called "immunosuppressive acidic protein," and its biological activities were discussed regarding its possible role in the impairment of the immunological surveillance mechanism in the tumor-bearing host.

An affinity adsorbent, 5'-adenylate-aminohexyl-sepharose. I. Purification and properties of two forms of RNase U2

An affinity adsorbent, 5'-adenylate-aminohexyl-Sepharose 4B, was prepared by the periodate oxidation of AMp followed by coupling and condensation with amino-hexyl-Sepharose 4B. RNase U2, a purine-specific RNase, was specifically bound to this adsorbent at pH 4.5 and eluted critically at pH 5.9 in the presence of 1 M NaCl, corresponding to the pH dependence of the binding of 2'-AMP to RNase U2. By using this affinity chromatography as a main tool, a simplified and effective purification method for RNase U2 was established with a high yield of 58%. Another form of RNase U2 with low specific activity, named RNase U2-B, was eluted at a slightly higher pH from this adsorbent. RNase U2-B was indistinguishable from the original enzyme (RNase U2-A) in base specificity, affinity for ApA, molecular weight and amino acid composition, but was clearly different in specific activity, molecular activity for ApA, isoelectric point and conformation of molecule. This affinity adsorbent is also effective for the detection or isolation of small amounts of base-specific RNases in crude cell extract.

Nonsteroidal antiinflammatory agents. 3. Synthesis of the positional isomers of 4'-chloro-5-methoxy-3-biphenylylacetic acid and their antiinflammatory and analgesic activities

The positional isomers 3a-i of 4'-chloro-5-methoxy-3-biphenylylacetic acid [1 (DKA-9), R = 4-ClPh; R' = MeO] which is a newly developed nonsteroidal antiinflammatory agent, have been prepared and evaluated for antiinflammatory and analgesic activities using both the carrageenan-induced rat paw edema and AcOH writhing assays. The 3- and 4-biphenylylacetic acids 3a,d, which closely resemble 1 (R = 4-ClPh, R' = MeO) structurally, showed, by far, excellent activities compared with the other isomers in these assays. However, none of the compounds tested was more active than 1 (R = 4-ClPh; R' = MeO). In this series of compounds, structural requirements for good antiinflammatory activity seemed to be parallel to those for analgesic activity.

The endocrine pancreas in pyridoxine deficient rats

Because the supplementation of pyridoxine (vitamin B6) improves the glucose tolerance in gestational diabetes and adult onset diabetes, pyridoxine deficiency has been considered to be one of the factors that cause diabetes mellitus. We produced pyridoxine deficient rats by giving pyridoxine-free food with deoxypyridoxine which competitively the activity of pyridoxal phosphate. In these pyridoxine deficient rats plasma insulin during the glucose tolerance test was significantly low as compared with controls. In vitro experiments of pancreas perfusion showed that secretion of insulin and glucagon was impaired in the pyridoxine deficiency. Since the restriction of diet-calorie caused a decrease in arginine-induced secretion of insulin and glucagon from the isolated pancreas, the impairment of the endocrine pancreas may depend on malnutrition. Pyridoxine deficiency is surely one of the factors that impair the endocrine pancreas by multifactorial derangement of metabolism besides the tryptophan-nicotinic acid pathway.

Nonsteroidal antiinflammatory agents. 2. Synthesis of 4',5-disubstituted 3-biphenylylacetic acids and their derivatives with antiinflammatory and analgesic activities

A series of 5',5-disubstituted 3-biphenylylacetic acids (5a-n) and several alpha-methyl derivatives (5o-v) were prepared as analogues of a newly developed nonsteroidal antiinflammatory agent, 5'-chloro-5-methoxy-3-biphenylylacetic acid [1 (DKA-9), R = 4-C1Ph; R' = Me], and evaluated for antiinflammatory and analgesic activities using both carrageenan rat paw edema and AcOH writhing assays. Among them, 5-fluoro-3-biphenylylacetic acid (5m) showed the highest antiinflammatory activity, while 2-(3-biphenylyl)propionic acid (5o) showed the highest analgesic activity. However, they were less potent than 1 (R = 4-C1Ph; R' = Me) in these assays.

Purification and properties of kynureninase from rat liver

Kynureninase [L-kynurenine hydrolase EC 3.7.1.3] has been purified 614-fold from rat liver cytosol. The purification procedure involved pH treatment, ammonium sulfate fractionation, Sephadex G-100 gel filtration, DEAE-Sepharose CL-6B chromatography, extraction with 40% saturated solution of ammonium sulfate and hydroxyapatite chromatography. The enzyme was found to be homogeneous by the criteria of disc gel electrophoresis. SDS-gel electrophoresis and sucrose gradient centrifugation. The enzyme was obtained as a holo-enzyme which showed an absorption maximum at 420 nm. In the absence of pyridoxal 5-phosphate (PLP) the enzyme was dissociated into an apoenzyme. The isoelectric points of holoenzyme and apoenzyme are 5.7 and 6.1. Sucrose gradient centrifugation and SDS-gel electrophoresis gave molecular weight estimates of 95,000 and 55,000, respectively. The optimum pH shifted to higher pH with increase in the concentration of PLP. The Michaelis constants were determined as follows: kynurenine, 240 microM; 3-hydroxykynurenine, 13 microM; PLP, 0.1-1.7 microM. The maximum velocity for 3-hydroxykynurenine was 11 times higher than that for kynurenine at pH 7.7. This enzyme can be regarded as a 3-hydroxykynureninase type enzyme.

Effect of 4'-chloro-5-methoxy-3-biphenylylacetic acid (DKA-9) on prostaglandin synthetase

4'-Chloro-5-methoxy-3-biphenylylacetic acid (DKA-9) was evaluated for its ability to inhibit the conversion of arachidonic acid into prostaglandin E2 and the oxygen uptake on arachidonic acid by sheep seminal vesicle microsomes. DKA-9 inhibited equally the formation of prostaglandin E2 and oxygen uptake at 20 mumol/l or more in a concentration-dependent manner, which suggests a blockade of prostaglandin endoperoxide formation. DKA-9 did not promote time-dependent inactivation of the enzyme and inhibited the enzyme competitively with respect to substrate. Thus, it behaved as a reversible and competitive inhibitor.

Inhibitory effect of cytokinins on PHA-induced human lymphocyte stimulation

The inhibitory effect of various purine derivatives on PHA-induced human lymphocyte blast formation was studied. Two nucleoside cytokinins, N6-benzyladenosine and N6-isopentenyladenosine, inhibited blast formation at concentrations as low as 10(-6) M. However, the other cytokinins, which lacked the ribosyl residue at N9 position, had to be at the higher molar concentration of 10(-4) before they could induce the same inhibitory effect.

Purification of L-kynurenine 3-hydroxylase by affinity chromatography

NADP immobilized on agarose is able to adsorb L-kynurenine 3-hydroxylase. The enzyme is released from the adsorbent by passage of a buffer containing 0.5 mM NADP through the column. L-Kynurenine 3-hydroxylase was purified 26-fold with a yield of 12% from mitochondrial outer membrane with a procedure involving DEAE-Sepharose CL-6B, Sephacryl S-200 chromatography and NADP-agarose affinity chromatography. This monooxygenase was a homogeneous protein, giving a monomeric molecular weight of 145,000, which had neither any significant NADPH diaphorase activity nor cytochrome b5-like haem protein. However, the enzyme did not show affinity for a column with L-kynurenine coupled to the gel with a suitable spacer group, and AMP did not serve as an effective ligand in an affinity resin.

Gap junctions in the cardiac muscle cells of the lamprey

Electron microscopy of both thin sections and freeze-fracture replicas has demonstrated the occurrence of gap junctions (nexuses) in the cardiac muscle cells of the lamprey. These gap junctions are identical in basic structure with those found in the mammalian heart. However, they are much smaller (less than 0.5 micron in diameter), and more irregularly distributed than the typical gap junction in the mammalian heart. These small gap junctions seem to provide a structural basis for the electrical coupling between cardiac muscle cells in the lower vertebrates. In addition, the well developed sarcoplasmic reticulum and subsurface cisternae, which contain an electron dense spheroidal cast, frequently observed in the cardiac muscles of the lamprey.

Fine structure and cytochemistry of specific granules in the lamprey atrium

Fine structural and cytochemical studies were performed to examine the nature of three types of specific granules found in the atrium of lamprey; specific granules of the atrial muscle cell (ASG), interstitial cell granules (ICG) and endocardial endothelial granules (ESG). Ultrastructurally, ASG and ICG appeared quite similar in size, shape and electron opacity, while ESG were much larger and less dense in opacity than the other two. None of the granules showed positive DAB reaction or acid phosphatase reaction. Only ICG revealed positive chromaffin reaction, which agreed with formaldehyde induced green fluorescence along the atrial lumen. Phosphotungstic acid at low pH stained ICG and ASG strongly positive, and ESG weakly positive. Pronase treatment in Epon sections for 24 h digested ASG alone, whereas in glycol-methacrylate embedded sections, ESG were digested first, ASG were digested thoroughly after 30 min, but ICG were not digested completely after 90 min. From these results it can be concluded that the three types of specific granules have different constituents. ESG consist of protein with some polysaccharides; ASG are composed of protein carbohydrate complexes and lack catecholamines; ICG contain catecholamine as well as protein carbohydrate complexes.

Kininase and anti-inflammatory activities of acid carboxypeptidase from Penicillium janthinellum

The acid carboxypeptidase from Penicillium janthinellum catalyzed the rapid release of arginine, and the slow release of phenylalanine, proline, serine and glycine from the carboxy-terminal of bradykinin at pH 4.15 to 4.8. Anti-inflammatory activity of the acid carboxypeptidase seems to suggest that the enzyme hydrolyzed bradykinin in vivo.

Induction of phage production in the lysogenic Escherichia coli by hydroxyurea

1) Hydroxyurea, a reversible DNA synthesis inhibitor, was used to study the mechanism of prophage lambda induction in Escherichia coli K12. Induction of prophage was judged on two criteria: increase of phage-producing cells and loss of colony-forming ability of the cells. 2) Hydroxyurea induced an increase of phage-producing cells only in lysogenic strains known to be inducible with ultraviolet irradiation for prophage development and not in strains such as E. coli K12 (lambdaind-) or E. coli K12 recA (lambda+). 3) When protein synthesis was inhibited, hydroxyurea did not increase phage-producing cells of lysogenic strains; it showed a bacteriocidal effect on lysogenic recA+ strains, but not on nonlysogenic strains. 4) The sensitivity of E. coli K12 recA to hydroxyurea was independent of whether or not the cells were lysogenic. 5) From the results it is suggested that certain steps leading to loss of colony-forming ability (i.e. prophage induction) do not require de novo protein synthesis but require the presence of the host recA+ gene.

Isolation of L-dynurenine 3-hydroxylase from the mitochondrial outer membrane of rat liver

Outer membrane preparations of rat liver mitochondria were isolated, after the mitochondria had been prepared by mild digitonin treatment under isotonic conditions. L-Kynurenine 3-hydroxylase [EC 1.14.13.9] was solubilized on a large scale from outer membrane by mixing with 1% digitonin or 1% Triton X-100, followed by fractionation into a minor fraction I and a major fraction II by DEAE-cellulose column chromatography. The distribution of total L-Dynurenine 3-hydroxylase was roughly 20 and 80% in fraction I and II, respectively. Fraction I consisted of crude enzyme loosely bound to anion exchanger. In the present investigation, fraction I was not used because of its low activity and rapid inactivation. In contrast, fraction II consisted of crude enzyme with high activity, excluded from DEAE-cellulose column chromatography in the presence of 1 M KC1. In addition, fraction II was purified by Sephadex G-200 gel filtration and DEAE-Sephadex A-50 column chromatography with linear gradient elution, adding 1 M KC1 and 1% Triton X-100 to 0.05 M Tris-acetate buffer, pH 8.1. After isoelectric focusing, the purified enzyme preparation was proved to be homogeneous, since the L-kynurenine 3-hydroxylase fraction gave a single band on disc gel electrophoresis. The molecular weight of this enzyme was estimated to be approximately 200,000 or more by SDS-polyacrylamide gel electrophoresis and from the elution pattern on Sephadex G-200 gel filtration. A 16-Fold increase of the enzyme activity was obtained compared with that of the mitochondrial outer membrane. The isoelectric point of the enzyme was determined to be pH 5.4 by Ampholine isoelectric focusing.