Effect of interferon γ on the sensitivity of bovine-papilloma-virus(BPV1)-transformed cell lines to cell-mediated cytotoxicity

Summary The effect of interferon (IFN) on the immunogenicity and immunosensitivity of mouse cell lines transformed by bovine papillomavirus type 1 (BPV1) DNA was examined in a syngeneic mouse model. The overnight incubation of BPV1-transformed cell lines with 100 IU/ml IFN did not affect their ability to induce the generation of cytotoxic effector cells but it clearly increased their sensitivity to lysis by interleukin-2-induced lymphokine-activated killer (LAK) cells and by nonspecific LAK-type effector cells induced by BPV-1-transformed cell lines. The treatment of two allogeneic lymphoid tumour cell lines, P815X2 and YAC-1, with IFN either decreased or had no effect on their sensitivity to LAK-cell-mediated lysis.     

Clinical studies on cell-mediated immunity in patients with renal cell carcinoma: interleukin-2 and interferon-γ production of lymphocytes

Summary The authors examined interleukin-2 (IL-2) production and interferon (IFN) production of peripheral blood mononuclear cells in 28 patients with renal cell carcinoma and 17 control subjects. The peripheral blood was obtained prior to the initiation of therapeutic procedures. The patients were divided into two groups according to tumor size, 5 cm and >5 cm. The production of IL-2 and IFN was measured by immunoradiometric assay. As a result, in the patients with tumors >5 cm, IL-2 and IFN production was impaired. However, in the patients with tumors 5 cm, IFN production was enhanced, though IL-2 production was not significantly different from that of the control subjects. There was no significant correlation between IL-2 production and IFN production.     

Immunocytochemical localization of conglutin γ and legumin-like globulin in developing and mature seeds ofLupinus albus L.

Summary The distribution of two seed proteins, namely conglutin and a legumin-like globulin, in developing and mature seeds ofLupinus albus L. has been examined by immunocytochemistry and the concomitant modifications of their constituent polypeptides followed by SDS-PAGE. Both proteins were found within vacuolar protein bodies in various tissues of the cotyledons, although with some differences in the distribution patterns. The legumin-like protein was found to be deposited within the large storage parenchyma cells of the cotyledons in a manner similar to that reported for other storage proteins; little or no immunolabelling was associated with the cotyledonary epidermal and vascular parenchyma cells. In contrast conglutin was present in all cell types.A precursor of the legumin-like protein accumulated transiently in the developing cotyledon, but was subsequently modified by proteolytic cleavage. The onset of such modification was concomitant with a transition in the predominant vacuolar forms within the storage parenchyma cells. No precursor molecules of conglutin have been detected in this study, thus indicating that this protein is deposited in the protein bodies in its mature form.Abbreviations LM light microscopy - EM electron microscopy - DAF days after flowering - SDS-PAGE sodium dodecyl sulphate polyacrylamide gel electrophoresis - GAR goat antirabbit antiserum     

Limited DNA elimination from the irradiated potato parent in fusion products of albino Lycopersicon esculentum and Solanum tuberosum

Summary This paper describes the analysis of the elimination of potato DNA from potato-tomato somatic cell hybrids. The hybrids were obtained by fusion of protoplasts of a cytoplasmic albino tomato genotype with leaf mesophyll protoplasts of a potato genotype carrying the -glucuronidase (GUS) gene of Escherichia coli. The potato protoplasts were either isolated from unirradiated plants or from plants irradiated with 50 or 500 Gy of -rays. Green calli were selected as putative fusion products. The hybridity of these calli was confirmed by isoenzyme analysis. All of the green calli tested contained a potato-specific chloroplast DNA restriction fragment, and most of the calli analysed were positive for -glucuronidase activity. In 72 of the hybrid calli we determined the percentage of potato nuclear DNA using species-specific probes. All of the tested green calli contained a considerable amount of potato genomic DNA, irrespective of the dose of irradiation of the potato parent. The limited degree of potato DNA elimination and the absence of true cybrids are discussed.     

微波辐射对小鼠脑内乙酰胆碱含量及胆碱乙酸转移酶活性的影响

用频率为2450MHz功率密度为10mW/Cm~2(WBASAR约11.4W/kg)的微波(连续波)对置于微波暗室内的昆明种雄性小鼠急性全身照射1小时后,立即按常规方法断头,取脑,制成样品,然后用放射免疫测定法测量小鼠脑内乙酰胆碱(ACh)含量及胆碱乙酰转移酶(ChAT)活性。结果表明:照射组的ACh含量为11.6±1.4pmol/mg(脑鲜重),ChAT活性为45.4±8.7pmolACh/min.mg(脑鲜重);而对照组的分别为16.0±2.1pmol/mg和61.0±13.8pmolACh/min.mg。证明微波照射后可引起动物脑内ACh水平和ChAT活性下降,提示微波辐射对中枢胆碱能系统确有不利影响。     

Glutamic acid decarboxylase of embryonic avian retina cells in culture: Regulation byγ-aminobutyric acid (GABA)

1. Retina-cell aggregate cultures expressed glutamate decarboxylase activity (L-glutamate 1-carboxylase; EC 4.1.1.15) as a function of culture differentiation. 2. Glutamic acid decarboxylase (GAD) activity was low in the initial phases of culture and increased eight-fold until culture day 7, remaining high up to day 13 (last stage studied). 3. The addition of GABA to the culture medium 24 h after cell seeding almost totally prevented the expression of GAD activity. 4. In association with decreased enzyme activity, aggregates exposed to GABA did not display immunoreactivity for GAD, suggesting that GAD molecules were either lost from GABAergic neurons or significantly altered with GABA treatment. 5. Control, untreated aggregates showed intense GAD immunoreactivity in neurons. Positive cell bodies were characterized by a thin rim of labeled cytoplasm with thickest labeling at the emergence of the main neurite. 6. Heavily labeled patches were also observed throughout the aggregates, possibly reflecting regions enriched in neurites. 7. The GABA-mediated reduction of GAD immunoreactivity was a reversible phenomenon and could be prevented by picrotoxin.     

Phase I trial of intravenous infusion of ex-vivo-activated autologous blood-derived macrophages in patients with non-small-cell lung cancer: Toxicity and immunomodulatory effects

Summary The purpose of this phase I study was to evaluate the toxicity and biological activity of autologous blood-derived macrophages activated ex-vivo with recombinant human interferon (rhuIFN) [monokine-activated killer (MAK) cells] and administered intravenously to 11 lung cancer patients once a week for 6 consecutive weeks. Peripheral blood monocytes were collected by leukapheresis and then purified by counterflow elutriation. The MAK cells were generated by culturing the purified monocytes in Teflon bags for 7 days and adding rhuIFN to the cultured cells for the last 18 h. These MAK cells expressed differentiation-associated surface antigen MAX1, and were cytotoxic in vitro against tumour cell line U937. The MAK cells were infused at dose levels from 1 × 10⁷ to 5 × 10⁸ on an intrapatient dose-escalating schedule. No severe adverse side-effects occurred. Toxicity was mild to moderate [primarly fever (75%) and chills (32%)], non-dose-dependent, and non-cumulative. No consistent change in haemostatic function, or liver or renal function was observed. Dose-limiting toxicity was not reached at 5 × 10⁸ cells (optimal dose reproduced for each patient). The maximum tolerated dose was not determined. The immunomodulatory activity of i.v. infused MAK cells was demonstrated both in vivo by significant increases in granulocyte count and neopterin level in the patients' peripheral blood postinfusion and in vitro by secretory products (IL-1. TNF, neopterin, and thromboplastin-like substance) in the culture supernatants. The in vivo traffic patterns of autologous MAK cells labelled ex-vivo with¹¹¹In oxine were studied in 7 patients. Gamma imaging showed an immediate but transient lung uptake (<24 h), and a progressive uptake of radioactivity in the liver and spleen was seen from 6 h to 72 h post-infusion. Our results indicate that the preparation of high numbers of autologous, blood-derived MAK cells is a feasible procedure, and their transfusion is safe for patients. This immunotherapeutic approach seems to be encouraging from the point of view of establishing an adjuvant therapeutic modality in cancer patients with minimal residual disease.This work was supported in part by a grant 6911 from the Association pour la Recherche contre le Cancer (ARC), grants from the Ligue Nationale contre le cancer and the Ligues Regionales (Bas-Rhin, Haut-Rhin) contre le cancer, and contract 891013 from the Institut National pour la Santé et la Recherche Médicale (INSERM), France     

Stomatal closure by ultraviolet radiation

The effect of ultraviolet radiation (UV) (255–325 nm) on stomatal closure was investigated on tef [ Eragrostis tef (Zucc) Trotter] in the presence of white light (ca 50 ·mol m⁻² s⁻¹). The action spectrum showed that UV (ca 2 ·mol m⁻² s⁻¹, half band width about 10 nm) of 285 nm or shorter wavelengths was very efficient in causing stomatal closure. The effectiveness decreased sharply towards longer wavelengths. Radiation of 313 nm or longer wavelengths was practically without effect. Increasing UV intensity increased stomatal resistance. When stronger white light (5 to 9 times stronger than the one used during irradiation) was administered, stomates re-opened rapidly irrespective of whether the UV was on or off, although a subsequent gradual closing tendency was observed when the UV was on.     

Composite Technique for Regional Neurochemical Studies: Measurement of Energy and Neurotransmitter Metabolites in Single Tissue Sample

A combined method is described for the determination of various metabolites from a single tissue sample of the brain. It comprises a quick inactivation of cerebral enzymes by microwave irradiation, easy separation of the desired brain regions, and perchloric acid extraction of tissue substances, which are assayed either by specific enzymatic techniques or by HPLC with electrochemical detection. The obtained values of most energy and neurotransmitter metabolites in the brain are in agreement with those reported using other methods. However, this technique, in contrast to the brain freezing in vitro or freeze-blowing, provides a more efficient procedure for rapid arrest of cerebral metabolism even in the deep brain structures and is therefore suitable for detection of early changes particularly those occurring in experimental pathological conditions such as ischemia.