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S M Russell

Publications and source records attributed to S M Russell.

At least 109 records · Page 6Linked to original sources
PubMed1984

Degradation of proteins in rat liver mitochondrial outer membrane transplanted into different cell types. Evidence for alternative processing.

The degradation of proteins in reductively [3H]methylated mitochondrial outer membrane (MOM) transplanted into cells by a poly(ethylene glycol)-mediated process has been studied. The average rate of degradation (t1/2 24-28 h) of MOM proteins transplanted into HTC cells was not the same as for endogenous MOM proteins (t1/2 56 h), mitoplast proteins (t1/2 120 h), plasma membrane proteins (t1/2 approx. 90 h) or cytosol proteins (t1/2 75 h). The degradation of transplanted MOM proteins was inhibited to the same extent (30-45%) as that of endogenous mitochondrial and plasma membrane proteins by leupeptin and NH4Cl. No inhibition of HTC cell cytosol protein degradation by NH4Cl was observed. NH4Cl differentially inhibited the degradation of endogenous MOM and mitoplast protein subunits as shown after sodium dodecyl sulphate/polyacrylamide-gel electrophoresis. Proteins in MOM transplanted into tissue culture cells were degraded either with t1/2 24-28 h (MRC-5, B82 and A549 cells) or with t1/2 55-70 h (CHO-K1 and 3T3-L1 cells) similar to that of proteins in MOM transplanted into rat hepatocytes [Evans & Mayer (1983) Biochem. J. 216, 151-161]. The data suggest that membrane protein destruction is but the end part of a fundamental intracellular membrane recognition process.

Ammonium Chloride↗
PubMed1984

Cross-protection in mice infected with influenza A virus by the respiratory route is correlated with local IgA antibody rather than serum antibody or cytotoxic T cell reactivity.

Mice previously infected with an aerosol of A/Rec 31 influenza virus were strongly protected against an aerosol challenge with A/Vic influenza as judged by lung virus titers recovered 2 days after the challenge infection. Such complete homotypic immunity was not achieved by priming with live Rec 31 virus injected i.v. or UV-inactivated Rec 31 virus administered s.c. together with Al(OH)3 and saponin. The reason for the superior protective effect of the natural infection was investigated. The protection induced by respiratory infection with Rec 31 virus was specific for influenza A viruses. It was not correlated with specific serum hemagglutination inhibition antibody titer or cross-reactive cytotoxic T (Tc) cell reactivity. Moreover, the transfer of splenic and lymphoid T cell populations with strong secondary Tc activity did not significantly reduce lung virus titers in recipient mice 3 days after infection. The protection however occurred in parallel with the presence of cross-reactive IgA antibody in the lung washings. It thus appears that local secretory IgA plays a causal role in the prevention of cross-infection by influenza A virus. Serum antibody and Tc cells, on the other hand, may be crucial for recovery from such infection. All mice primed with live Rec 31 virus, administered i.v. or by aerosol and expressing equally high levels of Tc reactivity, survived a lethal challenge with A/PR8 virus. The same challenge, however, killed half of the mice immunized s.c. with inactivated Rec 31 virus which induced only a low level of Tc reactivity.

Aerosols↗
PubMed1983

Degradation of transplanted rat liver mitochondrial-outer-membrane proteins in hepatoma cells.

Reductively [3H]methylated 3H mitochondrial-outer-membrane vesicles from rat liver and vesicles where monoamine oxidase has been derivatized irreversibly by [3H]-pargyline have been deliberately miscompartmentalized by heterologous transplantation into hepatoma (HTC) cells by poly(ethylene glycol)-mediated vesicle-cell fusion. Fluorescein-conjugated mitochondrial-outer-membrane vesicles have also been used to show that transplanted material is patched, capped and internalized. Reductively methylated outer-membrane proteins and monoamine oxidase are destroyed at the same rate (t1/2 24 h). Mitochondrial-outer-membrane proteins are not degraded at the same rate as HTC plasma-membrane proteins, endogenous cell protein, or endocytosed protein. Transplanted radiolabelled mitochondrial-outer-membrane proteins accumulate intracellularly in structures that are distinct from plasma membrane and lysosomes. However, when mitochondrial-outer-membrane vesicles derivatized with [14C]sucrose are transplanted, the acid-soluble degradation products accumulate in the lysosomal fraction. [14C]Sucrose-conjugated HTC cell plasma membrane accumulates in intracellular structures that are again distinct from plasma membrane and lysosomes. In contrast with the above observations, homologously transplanted mitochondrial-outer-membrane proteins from rat liver are destroyed in hepatocytes at rates that are remarkably similar (t1/2 60-70 h) to the rates in rat liver in vivo [Evans & Mayer (1982) Biochem. Biophys. Res. Commun. 107, 51-58].

Animals↗
PubMed1983

Study of heart-reactive antibody in antisera and hybridoma culture fluids against group A streptococci.

Heart-reactive antibody is known to be produced in animals immunized with group A streptococci. However, the detection and quantitation of these antibodies and their respective antigens have been limited to immunofluorescence or immunoprecipitation tests. In this study a more sensitive technique was used to detect heart-reactive antibody, i.e., the enzyme-linked immunosorbent assay (ELISA). Countercurrent immunoelectrophoresis and agar gel immunodiffusion were also used to confirm the reactivity of rabbit antisera to group A streptococci and human heart tissue. Human heart tissue antigen was prepared by Triton X-100 extraction, and checkerboard titrations of heart tissue antigen versus streptococcal antisera revealed optimal concentrations of each for the ELISA. When immune rabbit serum was reacted with heart tissue antigen, a 5- to 10-fold increase was observed over the reactions of preimmune sera controls. Streptococcal antiserum was found to have a six- to eightfold greater reactivity with heart tissue antigen than with similar concentrations of kidney and skeletal muscle antigens. Heart tissue antigen was partially purified by DEAE-cellulose chromatography, and quantities of greater than 10 to 100 ng (dry weight) were shown to react with streptococcal antisera in the ELISA. Heart, kidney, and skeletal muscle antigens were subjected to electrophoresis in polyacrylamide gel slabs and blotted onto a nitrocellulose filter. These filter blots reacted with streptococcal antisera and confirmed the tissue antigen specificity observed with the ELISA. In addition, the ELISA was found to be an effective method for the detection of heart-reactive antibodies produced by murine hybridomas that were producing antibody to group A streptococci.

Antibodies, Bacterial↗
PubMed1983

A transplant system for studying hormonal control of growth of fetal rat tissues: effects of hypophysectomy growth hormone, prolactin, and thyroxine.

Much uncertainty still exists about whether mammalian fetuses are dependent on and/or responsive to hormones that are growth promoting postnatally. To allow this problem to be investigated more meaningfully, a transplant system was developed. Paws from 14- to 15-day-old fetal rats were incubated under the kidney capsules of 28- to 30-day-old syngeneic female hosts for up to 11 days. After an initial lag period, the growth rate of the transplants was similar to that of in situ paws. The implants differentiated normally, and their histological structure as well as various biochemical indices were similar to those of in situ paws. Growth of paws in hypophysectomized (HX) hosts was reduced to 35% of that of transplants in intact hosts, but the HX hosts themselves showed total cessation of growth. Injections of T4 or PRL into HX hosts did not improve transplant growth, but GH restored paw growth almost completely. The combination of GH plus T4 was no more effective than GH alone. Doses of GH (in HX hosts) that restored growth of the fetal tissue to 80-95% of that of paws in intact hosts caused only a 20-60% restoration of growth of the HX hosts themselves. Our results indicate that the internal milieu of juvenile female rats is as suitable for the growth of fetal paws as the normal intrauterine environment. Furthermore, GH is needed to maintain that internal milieu for optimal growth of fetal tissue. Although the tissues of the fetal paw are less dependent on GH than are those of the juvenile hosts, they appear to be more responsive to the hormone.

Animals↗
PubMed1982

Protein degradation in rat liver. Evidence for populations of protein degradation rates in cellular organelles.

Protein degradation in liver subcellular and submitochondrial fractions from adult rats has been measured by a double isotope technique. Protein subunits have been resolved by two-dimensional polyacrylamide gel electrophoresis. No consistent relationship between subunit size or isoelectric point and degradation rate has been found in any fraction. Frequency analysis of isotope ratios for protein subunits in subcellular and submitochondrial fractions has been carried out. The analyses demonstrate that degradation rates of resolved protein subunits in organelles or organelle subcompartments can be grouped into populations. Resolved protein subunits in subcellular and submitochondrial fractions can be grouped into one, two or three populations. The results suggest limited heterogeneity of protein degradation rates within each subcellular organelle and support the notion that morphological subcompartment rather than molecular property may be the prime determinant of rates of degradation of individual proteins.

Animals↗
PubMed1981

Differential effects of somatostatin on the release of bioactive and immunoactive rat growth hormone in vitro.

The effects of linear (L) or cyclic (C) somatostatin (SRIF) on the release of growth hormone (GH) as measured both by bioassay and by radioimmunoassay (RIA) were studied in a series of incubation experiments with rat adenohypophyses. Although both forms of SRIF inhibited release of RIA-GH in all experiments, only C-SRIF appeared to inhibit release of bioactive GH. L-SRIF even enhanced release of bioassayable GH in one study. Addition of C-SRIF to medium containing secreted GH strongly inhibited the tibial growth response of the bioassay animals, while it had no effect on the measurement of GH by the RIA. Thus, the apparent inhibitory effect of C-SRIF on release of bioactive GH may be an artifact. The conclusion was supported by experiments in which the SRIF was not removed from the medium prior to assay by dialysis or by neutralization with anti-SRIF antiserum. After these manipulations, the inhibition by C-SRIF of the secretion of bioactive GH was eliminated, whereas the inhibitory effect on RIA-GH release was not affected. These results support other evidence for the differential release of rat GH with varying immuno-and bioactivities by different stimuli.

Animals↗
PubMed1981

A candidate reference method for determination of total protein in serum. II. Test for transferability.

The transferability of the candidate Reference Method for total serum protein was tested in eight laboratories in the United States and Europe. National Bureau of Standards SRM 927 (bovine serum albumin) was used in each analytical run as the calibration standard. The mean absorptivity value obtained for this material was 0.2983 L g-1 cm-1. Four serum pools prepared at the Centers for Disease Control were analyzed on each of 15 days. Within-run variation of the protein values (expressed as CV) in the eight laboratories ranged from 0.1 to 2.5% and day-to-day (total) variation in six of the laboratories ranged from 0.4 to 1%.

Biuret Reaction↗
PubMed1981

Characteristics of protein degradation in liver and mammary gland.

There is no correlation of protein degradation rate (measured by double isotope methods) with protein subunit molecular weight or isoelectric point in liver subcellular and suborganelle fractions and mammary cytosolic fractions. Most isotope ratios in each fraction fall in exponential distributions corresponding to populations of protein degradation rates; there is no statistically significant difference between protein degradation rates within several populations. The prime determinant for the degradation of proteins in these populations may be the morphological localization of the proteins. Pulse-chase labelling profiles indicate that a considerable proportion of newly-synthesised casein is rapidly degraded in mammary explants from mid-pregnant rabbits. This casein degradation is not co-translational; it appears to be a lysosomally-mediated event. In mammary tissue, the intracellular calcium concentration may acutely regulate synthesis and degradation of intracellular proteins, and the synthesis of casein.

Animals↗
PubMed1980

Protein degradation in rat liver during post-natal development.

Protein degradation rates for liver subcellular and submitochondrial fractions from neonatal (8-day), weanling (25-day) and adult rats were estimated by the double-isotope method with NaH14CO3 and [3H] arginine as the radiolabelled precursors [Dice, Walker, Byrne & Cardiel (1978) Proc. Natl. Acad. Sci. U.S.A. 75, 2093-2097]. Decreased protein degradation rates were found during post-natal development for homogenate, nuclear, mitochondrial, lysosomal and microsomal proteins. A decrease in degradation rates for the immunoisolated subunits of monoamine oxidase and pyruvate dehydrogenase was also observed in neonatal and weanling rats respectively. The results suggest coordinate degradation of the subunits of the multi-subunit enzyme pyruvate dehydrogenase. Pyruvate dehydrogenase has a faster rate of degradation in adult rat liver than does cytochrome oxidase. Data analysis suggests heterogeneity of protein degradation rates in the mitochondrial outer membrane and intermembrane space fractions at each developmental stage but not in the mitochondrial inner membrane or matrix fractions. Results obtained for protein degradation rates in adult rat liver by the method of Burgess, Walker & Mayer [(1978) Biochem. J. 176, 919-926] in general confirmed the results obtained for the adult rat liver by the above method. No evidence of a subunit-size relationship for protein degradation was found for proteins in any subcellular or submitochondrial fraction.

Animals↗
PubMed1980

Delayed-type hypersensitivity to influenza virus. Induction of antigen-specific suppressor T cells for delayed-type hypersensitivity to hemagglutinin during influenza virus infection in mice.

Mice infected with A/England/939/69 X A/Puerto Rico/8/34 (Rec 31) influenza virus by aerosol develop significantly lower levels of delayed-type hypersensitivity (DTH) to A/Hong Kong/1/68 X A/Puerto Rico/8/34/ (X31) virus compared to uninfected mice. The suppression of DTH to the hemagglutinin appears to be mediated by suppressor T cells which carry Lyt-1 membrane antigen marker, and not by sy serum antibody. The suppressor T cells for DTH induced by Rec 31 virus (H3N1) infection suppress the DTH response to the variants of the H3 subtype of influenza viruses, but have no effect on the DTH responses to A/Puerto Rico/8/34 virus (H0N1), a B influenza virus or the matrix protein of type A influenza virus. Suppressor T cells for DTH appear 2 wk after infection and are detectable in the spleen for at least 40 d thereafter. T-helper cells for antibody response to hemagglutinin are induced concomitantly with the T-suppressor cells for DTH. Possible implications of the present findings on the regulation of the immune response to viral infection are discussed.

Animals↗
PubMed1980

Cell cooperation in antibody responses to influenza virus. I. priming of helper t cells by internal components of virion.

T cells recognizing internal components of the influenza virion can cooperate with B cells recognizing hemagglutinin to enhance the hemagglutinin inhibition (HAI) antibody response. Cooperation occurs only when the internal proteins and hemagglutinin are subsequently presented in association. The effect enhances the production of both 2-mercaptoethanol-resistant and -sensitive antibodies. The cooperating cells express the Thy-1+, Ly-1+2- surface phenotype and thus are characteristic of helper T cells. Immunization of mice with the internal components of the virion increases survival after exposure to lethal influenza infection. Mice primed with purified matrix protein produce enhanced amounts of HAI antibody after infection with influenza. These results may help to explain reports on the effects of heterotypic infection on antibody production, and also heterotypic immunity.

Animals↗
PubMed1979

The vectorial orientation of human monoamine oxidase in the mitochondrial outer membrane.

1. The localization of monoamine oxidase in the mitochondrial outer membrane was studied in preparations of human liver mitochondrial and brain-cortex non-synaptosomal and synaptosomal mitochondria. 2. Immunochemical accessibility in iso-osmotic and hypo-osmotic mitochondrial preparations was used to localize the enzyme. 3. It was shown that the immunochemically accessible tyramine-oxidizing activity was distributed approximately equally on both surfaces of the membrane in human liver and brain-cortex non-synaptosomal mitochondria. However, the immunochemically accessible beta-phenethylamine-oxidizing activity was situated predominantly on the outer surface, and the immunochemically accessible 5-hydroxytryptamine-oxidizing activity was situated predominantly on the inner surface of the mitochondrial outer membrane in liver and brain-cortex non-synaptosomal mitochondrial preparations. 4. Considerable variation in the distribution of the enzyme in preparations of synaptosomal mitochondria was seen. 5. The simplest model consistent with our observations is that, in liver and brain-cortex non-synaptosomal mitochondria, the tyramine-oxidizing activity is distributed on both sides of the mitochondrial outer membrane, the beta-phenethylamine-oxidizing activity is located on the outer surface of the outer membrane and the 5-hydroxytryptamine-oxidizing activity is located on the inner surface of the mitochondria outer membrane.

Aged↗
PubMed1979

Immunochemical characterization of monoamine oxidase from human liver, placenta, platelets and brain cortex.

1. Antiserum raised to purified human liver monoamine oxidase was used to characterize the monoamine oxidase from human liver, brain cortex, placenta and platelets. 2. Antibodies to monoamine oxidase were purified by adsorption with a mitochondrial preparation. 3. Monoamine oxidase was present in liver particle-free supernatant as measured by enzyme activity and immunodiffusion. 4. Multiple precipitin lines were obtained on immunodiffusion analysis against the purified liver enzyme. It is proposed that this is due to either aggregation or to differential lipid binding. 5. The results suggest that the functionally different enzymes found in liver, brain cortex, platelets and placenta are immunochemically related and may be identical.

Antigens↗