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PubMed1980

Reduction of suppressor cells in cancer patients treated with OK-432 immunotherapy.

OK-432, a streptococcal preparation, was intradermally injected daily into patients with advanced cancer of the stomach or lung for 4 weeks and the effects of OK-432 on the mitogenic responses of cancer patients were followed. The cells involved in the depression of the response of untreated cancer patients were characterized. The cells responsible for impaired responses were nylon wool non-adherent and suppressed the mitogen responses of autologous and allogeneic lymphocytes. These cells lost their suppressive activity during 7 days' culture in vitro. Following OK-432 immunotherapy, mononuclear cells from cancer patients showed increased responses to PHA and Con A, and nylon wool non-adherent cells did not inhibit the mitogen responses. These results suggest that the cells suppressing non-specific mitogen responses are sensitive to in vitro culture, belong to nylon wool non-adherent cells and are lost during 4 weeks of OK-432 therapy.

Adult↗

PubMed1996

Biopersistence of man-made vitreous fibers and crocidolite asbestos in the rat lung following inhalation.

This study investigated possible relationships between fiber bio-persistence in the lung and previously observed differences in pulmonary toxicity between asbestos and man-made vitreous fibers (MMVF) following inhalation exposure. Fischer 344/N rats were exposed nose only, 6 hr/day for 5 days to 30 mg/m3 MMVF (two fiberglass compositions, rock wool, or slag wool) or to 10 mg/m3 crocidolite asbestos. At eight time points up to 1 year postexposure, lung fiber burdens were analyzed for number/lung and bivariate dimensions using scanning electron microscopy (SEM) and for chemical composition using SEM energy dispersive spectroscopy. After 365 days, > 95% of long (> 20 microns) MMVFs had disappeared from the lung compared to only 17% of long crocidolite fibers. Longer MMVFs disappeared more rapidly than short MMVFs, suggesting that long fibers were dissolving or breaking. Mean diameters and lengths of the MMVFs decreased with time, while the mean diameter of crocidolite remained unchanged and its mean length showed an apparent increase, probably related to macrophage-mediated clearance of short fibers. Leaching of oxides occurred in the fibrous glasses and slag wool and correlated with morphological changes in the fibers over time. No chemical or morphological changes were observed in crocidolite fibers. These changes in MMVF number, chemistry, and morphology over time in lung tissue compared to crocidolite asbestos demonstrate the relatively low biological persistence of some MMVFs in the lung and may explain why these MMVFs are not tumorigenic in rats, even after chronic exposure at high concentrations.

Administration, Inhalation↗

PubMed1981

Regulation of the human allogeneic proliferative response in vitro.

We have investigated the glass-wool-adherent characteristics of human lymphocytes able to suppress allogeneic proliferation in vitro. We observed that: (1) Suppressor cells obtained after in vitro priming and their precursors are adherent to glass wool, whereas cytotoxic cells and their precursors are not; (2) primed cells adherent to glass wool are mainly HLA-DR positive, while nonadherent cells are HLA-DR negative or weakly positive; (3) the nonadherent, unprimed T cells used as responder cells in a primary MLR are more readily suppressed by suppressor cells than the same cells unfiltered. This may suggest an enrichment of 'acceptor' cells for suppression.

Cytotoxicity, Immunologic↗

PubMed1983

Human spleen cells mediating natural killing: altered natural cytotoxicity of spleen effector cells from patients with carcinoma.

Spleen cells from eight patients with abdominal carcinoma and six patients undergoing major surgery for a variety of disease entities were assayed for natural cytotoxicity towards 51Cr-labelled K 562 target cells. Patients with abdominal cancer were shown to have relatively weak splenic natural cytotoxicity compared with the reactivity of effector cells from non-carcinoma patients. Nylon wool non-adherent spleen effector cells from cancer patients showed reduced cytolytic capacity compared with effector cells prepared from the spleens of other patients or peripheral blood mononuclear cells (PBMC) obtained from healthy individuals, whereas the splenic reactivity of non-cancer patients showed the same nylon wool separation profile as PBMC, high cytolytic activity being associated with nylon wool non-adherent effector cells. Splenic effector cell cytotoxicity from cancer and non-cancer patients was enhanced following exposure to human interferon, and inhibited by treatment with cholera toxin and simple sugars. Furthermore, fractionation of spleen cells on Percoll discontinuous density gradients demonstrated natural cytotoxic activity to reside predominantly in the low density cell fractions, similar to that found with NK cells from peripheral blood. Thus the properties described here for human cytotoxic spleen cells are similar to those described for peripheral blood NK cells, suggesting these two effector cell populations to be closely related, if not identical.

Adult↗

PubMed1979

[Quantitative determination of protein, albumin, and antibiotics in nasal secretions of healthy probands (author's transl)].

This study on the pharmacokinetics of antibiotics in nasal secretions was carried out with two orally applicable penicillin derivatives which show different resorption patterns. Each of the antibiotics (Ampicillin and Bacampicillin) was given in equimolar doses to 20 healthy young volunteers, with normal mucosa, in a double blind cross over fashion. Nasal secretions were collected 1, 2, 3, 4, 6, and 8 h after the application of a single dose to the overnight fasted persons. In 10 of them blood was taken at 0.5, 1, 1.5, 2, 3, and 4 h after the administration. For the sampling of the nasal secretions cotton wool was weighed together with an airtight vial containing 300 microliter of phosphate buffered saline (PBS). The dry cotton wool stayed in the nasal cavity for 20 min, was then put into the PBS and weighed again. The difference determines the amount of secretions collected. After 30 min the soaked cotton wool was pressed out into a vial with a sterile syringe. One hundred microliters of this solution was taken to determine the antibiotic concentration by a micromodification of the agar diffusion technique. In the remaining fluid total protein and albumin were quantitatively determined. The amount of nasal secretions which have been collected are, on average, independent of the time (Fig. 1). With rising secretion the protein content decreases (Fig. 5) as is the case with the albumin concentration. Regarding all persons, the protein content and albumin (Fig. 4) remain constant during the experiment from 8 a.m. to 4 p.m. The differences between the values shown in the figures are not significant. Comparing the mean concentration for the antibiotic at different times after the application, it is obvious that the agents show different curves (Fig. 6). With ampicillin the maximum of 0.13 microgram/ml is reached at 2 h after the administration whereas with becampicillin the maximum of 0.84 microgram/ml is reached after 1 h. The concentrations in the nasal secretions are clearly dependent of the serum values. In the serum the maximum of the mean values plotted against the time of 2.7 microgram/ml is to be found at 2 h, if ampicillin is given, whereas the maximum of 9.3 microgram/ml is reached at 1 h after bacampicillin administration. In both cases in serum and nasal secretions the mean concentration maximum is about three times higher after bacampicillin as compared with ampicillin. As a reference for the concentration of the antibiotic the total protein content of the sample is more suitable as compared with sample volume and albumin because of its easy and exact determination. The results show that the nasal secretions can be used as a model to evaluate the pharmacokinetics in the mucosa of the upper respiratory tract if an adequate number of test persons is used.

Adult↗

PubMed1982

Modulation of antitumoral antibody-dependent cellular cytotoxicity and natural killer activity by Adriamycin and daunorubicin.

Mouse effector cells isolated from various anatomical sources failed to mediate antibody-dependent cellular cytotoxicity (ADCC) against alloantiserum-coated L1210 murine leukemia cell targets, whereas rat spleen cells appeared to be potent mediators of this activity. Following suppression of effector cell function 3 days after a single drug injection, the nylon wool non-adherent population of rat spleen cells from daunorubicin (DM)-treated rats demonstrated an increased ability to mediate ADCC compared to controls. Alternatively, although suppression occurred at day 7, no rebound enhancement was demonstrated by the same cell population isolated from Adriamycin (AM)-treated animals for as long as 12 days post-injection. Natural killer (NK) activity, measured as the ability of the nylon wool non-adherent rat spleen cell population to lyse uncoated L1210 cells, was modulated by drug treatment in a similar manner at each time point although the changes were not significant. In contrast to NK cells for which a substantial amount of activity remained adherent to nylon wool, all K cell activity was found in the non-adherent spleen cell population. The effector cell, in both cases, was not susceptible to antithymocyte serum plus complement treatment; however, NK activity appeared trypsin-sensitive whereas K cell activity did not. Therefore, AM and DM demonstrated different activities with regard to in vivo modulation of antitumoral ADCC.

Animals↗

PubMed2004

Utilization of microbial biofilms as monitors of bioremediation.

A down-well aquifer microbial sampling system was developed using glass wool or Bio-Sep beads as a solid-phase support matrix. Here we describe the use of these devices to monitor the groundwater microbial community dynamics during field bioremediation experiments at the U.S. Department of Energy Natural and Accelerated Bioremediation Research Program's Field Research Center at the Oak Ridge National Laboratory. During the 6-week deployment, microbial biofilms colonized glass wool and bead internal surfaces. Changes in viable biomass, community composition, metabolic status, and respiratory state were reflected in sampler composition, type of donor, and groundwater pH. Biofilms that formed on Bio-Sep beads had 2-13 times greater viable biomass; however, the bead communities were less metabolically active [higher cyclopropane/monoenoic phospholipid fatty acid (PLFA) ratios] and had a lower aerobic respiratory state (lower total respiratory quinone/ PLFA ratio and ubiquinone/menaquinone ratio) than the biofilms formed on glass wool. Anaerobic growth in these systems was characterized by plasmalogen phospholipids and was greater in the wells that received electron donor additions. Partial 16S rDNA sequences indicated that Geobacter and nitrate-reducing organisms were induced by the acetate, ethanol, or glucose additions. DNA and lipid biomarkers were extracted and recovered without the complications that commonly plague sediment samples due to the presence of clay or dissolved organic matter. Although microbial community composition in the groundwater or adjacent sediments may differ from those formed on down-well biofilm samplers, the metabolic activity responses of the biofilms to modifications in groundwater geochemistry record the responses of the microbial community to biostimulation while providing integrative sampling and ease of recovery for biomarker analysis.

Acetates↗

PubMed2001

Does ascorbic acid prevent retinopathy during interferon therapy in patients with chronic hepatitis C?

PURPOSE: Ascorbic acid was administered to patients with chronic hepatitis C to elucidate the mechanism of onset of retinopathy during interferon (IFN) therapy, and its prevention. METHODS: The subjects were 62 patients with chronic hepatitis C who had been admitted to our hospital. For the IFN therapy, 6 MIU of natural IFN-alpha, or 10 MIU of recombinant human IFN-alpha 2b was administered every day for the first 2 weeks, followed by administration three times a week for 22 weeks. The patients were randomly assigned to a group receiving 600 mg/day of ascorbic acid or a group not receiving ascorbic acid (control group). The optic fundi were examined by ophthalmologists before the IFN therapy began and subsequently at weeks 2 and 4 and then every 4 weeks during the IFN therapy. RESULTS: Retinopathy was found in 9 of the 31 patients (29%) in the ascorbic acid-treated group and in 11 of the 31 patients (35%) in the control group. The cumulative incidence of hemorrhage in the ascorbic acid-treated group was lower than that in the control group during the IFN therapy, but the difference between the two groups was not significant (P = 0.186). The cumulative incidence of cotton-wool spots in the ascorbic acid-treated group was almost same as that in the control group during the IFN therapy. The median platelet counts before the therapy was begun were 11.8 x 10(4)/mm2 in the group with hemorrhage and 16.6 x 10(4)/mm2 in the group without, and the lowest platelet counts during IFN therapy were 7.3 x 10(4)/mm3 in the group with hemorrhage and 9.5 x 10(4)/mm3 in the group without, indicating significantly lower values in the group with hemorrhage (P = 0.018 and P = 0.020, respectively). The lowest platelet counts during IFN therapy were 7.4 x 10(4)/mm3 in the group with cotton-wool spots and 9.7 x 10(4)/mm3 in the group without, indicating a significantly lower value in the group with cotton-wool spots (P = 0.036). CONCLUSIONS: Ascorbic acid was not considered to be useful for the prevention of the retinopathy associated with IFN therapy in patients with chronic hepatitis C.

Adult↗

PubMed1985

Retinopathy associated with acute pancreatitis.

Two patients (a 28-year-old woman and a 23-year-old man) with acute pancreatitis developed severe visual loss. The acute stage of retinopathy consisted of retinal edema, cotton-wool patches, and retinal hemorrhages, predominantly in the posterior pole of both eyes. During the five-year follow-up period, visual acuity improved and sequential fluorescein angiography of both patients demonstrated reperfusion of previously occluded retinal vessels. After resolution of the cotton-wool patches, the previously edematous areas were replaced by foci of retinal thinning which created irregularities in the internal limiting membrane light reflex. Visual fields demonstrated scotomas corresponding to the areas of the previous cotton-wool patches.

Acute Disease↗

PubMed1987

Antigen-specific augmentation factor involved in murine delayed-type footpad reaction. IV. Effect of delayed-type hypersensitivity augmentation factor on in vitro induction of DTH.

We found an antigen-specific factor capable of augmenting delayed-type hypersensitivity (DTH) in the serum of mice sensitized with heterologous erythrocytes to induce a delayed footpad reaction (DFR), or in the culture supernatant of the mixture of sensitized T cells and specific antigens. This factor (DTH augmentation factor; DAF) was confirmed to augment DTH in transferred recipients. In this paper, such an activity of DAF was further investigated using the system with in vitro induction and local transfer of DTH. DAF also augmented the primary in vitro induction of DTH, when spleen cells from mice transferred with the DAF-containing serum 12 hr previously or spleen cells incubated with the DAF-containing serum on ice for 2 hr were cultured with heterologous erythrocytes. DAF acted on the induction phase of DTH and augmented a typical DTH which was dependent on Thy-1-positive T cells. DAF showed antigen specificity, but was not assigned to conventional immunoglobulin. The activity of DAF was detected when nylon-wool nonadherent cells were incubated with DAF prior to the culture of those cells and antigens, but not detected when only nylon-wool adherent cells were incubated with DAF. Thus, DAF exerted its effect through binding to acceptor cells which were included in nylon-wool nonadherent spleen cells from normal mice.

Animals↗

PubMed1995

Kinetic disposition of an emulsifiable concentrate formulation of deltamethrin applied to sheep in a plunge-dip and its effect on lice.

An emulsifiable concentrate formulation of the synthetic pyrethroid insecticide deltamethrin was applied in a plunge dip, 3 weeks after shearing, to a group of 5 Merino sheep infested with sheep body lice, Bovicola ovis. Deltamethrin concentrations on the wool were measured at regular intervals between 1 and 98 days after treatment and were not significantly different (P > 0.05) between sites on the dorsal mid-line, upper or lower flank. Levels in the tip of the fleece were significantly greater than those in the base, indicating that there was little movement of deltamethrin down the staple as the wool grew. Most lice were killed after 20 h of exposure in vitro to wool samples collected between 1 and 28 days after treatment. However, many lice survived in samples containing a similar concentration of deltamethrin, but collected between 35 and 98 days after treatment. Numbers of lice surviving increased with the sampling time after treatment, suggesting that the bioavailability of the deltamethrin changed as the insecticide aged in the fleece. Some transfer of deltamethrin occurred from treated to untreated sheep. The levels of deltamethrin were higher in sheep placed in contact with the treated group at 14 days after treatment than in those which were in contact from 43 days after treatment.

Animals↗

PubMed1986

Generation of purified stromal cell cultures that support lymphoid and myeloid precursors.

Treatment of Dexter-type long-term bone marrow cultures with the antibiotic mycophenolic acid (MPA) eliminates all hemopoietic cells from the cultures, while a morphologically intact, adherent stromal cell layer is retained. The ability of these MPA treated stromal cell cultures to support long-term hemopoiesis was tested by seeding them with fresh bone marrow cells that had been passed through nylon wool. This procedure yields a relatively stromal cell depleted population of hemopoietic cells. An aliquot of 5 X 10(5) or 2.5 X 10(5) nylon wool passed bone marrow cells bearing the T6 chromosomal marker was seeded onto replicate MPA-treated stromal cell layers. The stromal cells stimulated the proliferation of the bone marrow cells, and nonadherent cells were present for up to 8 weeks of culture. Progenitors of granulocytes and macrophages (CFU-GM) were also present for this period of time despite weekly demi-depopulation, during culture feeding. Karyotypic analysis confirmed that the CFU-GM were derived from the reseeded population. Nylon wool-passed bone marrow cells seeded alone into empty flasks under identical conditions did not survive past 1 week. Cells from the reseeded cultures were also tested for early myeloid precursors (CFU-S) and injected into immunodeficient CBA/N mice to test for the presence of primitive B cell precursors. CFU-S were present in mice killed 11 days following injection of cells, and high levels of B cell colony-forming units (CFU-B) were present in mice 4 weeks post reconstitution. Further studies demonstrated that factors present in medium conditioned by the stromal cells could support the growth of CFU-GM. These data indicate that treatment of long-term bone marrow cultures with MPA results in a population of functional stromal cells.

Animals↗

PubMed1988

Enrichment of murine splenic natural killer (NK) cells by the sequential elimination of non-NK cells.

A simple and reliable three-step procedure to enrich for murine endogenous splenic NK cells is described. The method is based on the sequential elimination of non-NK cell subsets by standard and inexpensive techniques executed in a specific order. First, macrophages and other adherent cells are eliminated by incubation on plastic surface. Secondly, the T cells are excluded from the multicellular aggregates formed by agglutination of the remaining cells with wheat germ lectin. Thirdly, after dissociation of the aggregates with N-acetyl-D-glucosamine and osmotic lysis of erythrocytes, NK cells are separated from other nucleated cells by nylon wool filtration. C57BL/6 spleen cells were used to establish the enrichment procedure. Usually their NK cell activity is intermediate but occasionally either low or high NK cell activity was observed in input cell suspensions. The NK cell activity recovery and the degree of enrichment varied inversely with the initial NK cell activity level of the input cell suspension. When initial NK cell activity was intermediate, it was enriched 10-30-fold. Experiments were done to establish if suppressor cells, and nylon wool-adherent, naturally activated NK cells, putatively present in input cells, could have been responsible for the abnormal initial NK cell activity detected in some C57BL/6 spleen cell suspensions and for the variations in the degree of enrichment achieved by the method here described. Either no or negligeable suppressor cell activity was noted in the cell fractions normally discarded at each step of the procedure. On the other hand, nylon wool-adherent NK cells were eliminated during the fractionation of spleen cells with higher than average initial NK cell activity and would account for the lower NK cell enrichment obtained in these conditions.

Animals↗

PubMed1992

A rapid method for isolating murine intestine intraepithelial lymphocytes with high yield and purity.

Because murine intestine intraepithelial lymphocytes (IEL) are dispersed throughout the intestine epithelium, it is important that IEL extraction procedures result in lymphocyte preparations of sufficient purity for use in in vitro and in vivo experimental systems. Here, we describe an improved technique for isolating murine IEL consisting of a single 30 min extraction followed by multiple nylon wool filtrations and centrifugation through Percoll. This procedure yields a preparation of IEL with high overall recovery and purity yet takes only 2-2.5 h. Evaluation of individual steps in the extraction process indicated that nylon wool filtration, in particular multiple filtrations, and Percoll fractionation both were important for achieving highly-enriched IEL populations by removal of enterocytes and cellular debris, and demonstrated that multiple nylon wool filtration improved the overall IEL recovery. This procedure has several advantages for studies of murine IEL in that the resultant IEL population is ideal for phenotypic, functional, or molecular analyses. Moreover, this technique is effective for isolating IEL on a single-animal basis, thereby permitting analyses of IEL from individual mice rather than as pooled IEL obtained from several animals.

Animals↗

PubMed1990

Effect of pheromones from male goats on LH-secretion in anoestrous ewes.

Pheromones from ram's wool or buckhairs lead to an increase in the LH pulse frequency, thus inducing ovulations in seasonally anoestrous sheep and goats, respectively. Indications exist that pheromones from one species may be active in the other one. The changes of the LH secretion pattern were used as a bioassay to demonstrate such an interspecies effect of either ram's wool or buckhairs. A clear increase in the LH pulse frequency was obvious in ewes after stimulation with buckhairs (p less than or equal to 0.001, n = 11), but was absent in does after application of ram's wool or its extracts. Organic solvent extracts from buckhairs were split into a neutral (FN) and an acid fraction (FA). The latter one was further divided into two subfractions (FA-I, FA-II) according to the chain length of the fatty acids. The most pronounced effect was found after FN (p less than or equal to 0.001, n = 12), but FA still remained significantly active (p less than or equal to 0.05, n = 9). The subfractions FA-I and FA-II, however, had largely lost the pheromonal activity. It is concluded that buck pheromones are active in sheep. The neutral fraction is likely to contain the bulk of pheromonally active substances.

Animals↗

PubMedDate not supplied

Regulatory effects of thymus humoral factor on T cell growth factor in aging mice.

The effect of thymus humoral factor (THF) on T cell growth factor (TCGF) production by T cells and the association between splenic macrophages and T cells from young (2-3 months) and old (20-24 months) mice in this respect were studied. Splenocytes were divided into three groups: stimulated with concanavalin A (Con A); preincubated with THF and then stimulated with Con A; or stimulated with Con A and thereafter incubated with THF. These cells were then examined for production of TCGF. Cells treated with Con A and THF as described above were passed on nylon wool to enrich T cell populations and added to mitogen-sensitized (Con A or lipopolysaccharide) adherent splenocytes of old and young mice in the following combinations: young adherent and young T cells; young adherent and old T cells; old adherent and young T cells; and old adherent and old T cells. The results demonstrated that: (A) cells of old mice produced less TCGF than the young; (B) preincubation of splenocytes or nylon-wool enriched T cells with THF increased the production of TCGF consistently in young mice, whereas in the old a significant increase was observed only in some cases; (C) depressed TCGF activity was observed when treatment with THF to splenocytes or nylon-wool enriched T cells from young and old mice was performed after Con A stimulation, and this was also more pronounced in the young; (D) the reduced level of TCGF in the old seemed to be related to a lesion in the T cell compartment, since adherent cells from old and young mouse spleens could support TCGF production by T cells from young mice and not from old.

Aging↗

PubMed1993

Macrophages suppress lectin-induced proliferation of lymphocytes from aged rats.

Splenocytes from old rats exhibit a significant reduction in proliferative responses to Con A. This defect can be overcome by passing the cells over nylon wool, which suggests that nylon wool adherent cells contribute to the reduction in proliferation of mixed cell populations from aged rats. To examine the potential role of macrophages in this process, thioglycollate-elicited peritoneal macrophages were added to Con A-activated spleen cells from young and old rats. Addition of as few as 3% macrophages suppressed proliferation of Con-A-activated splenocytes and this inhibition was significantly greater if either the macrophages or spleen cells were derived from aged rats. Although prostaglandin E2 (PG-E2) inhibited the proliferation of splenocytes and nylon-wool enriched splenocytes from 3-month-old animals, its suppressive effects were much greater on Con A-activated lymphocytes derived from 24-month-old rats. Addition of catalase to deplete macrophage-derived H2O2 resulted in greater augmentation of Con-A-induced proliferative responses of splenocytes from old rats than those from young rats. TGF-beta 2, but not TNF-alpha, also significantly suppressed the proliferation of Con A-activated splenocytes to a greater degree in aged than in young rats. Since macrophages are known to release PG-E2, H2O2 and TGF-beta 2 after stimulation with Con A, these data support the idea that T cells within the splenocyte population become increasingly susceptible during aging to inhibitory products released by macrophages.

Aging↗

PubMed1986

Effects of nutritional environment and ram effect on breeding season in range sheep.

Effects of season, nutritional environment, and presence of rams on incidence and rate of ovulation in fine-wool sheep in southern New Mexico were investigated over 14 months (February 1983-March 1984). Number of corpora lutea (CL) were observed each month by laparoscopy in random samples from six ewes in each subgroup. Seasonality of ovulation in fine-wool sheep managed on range was much more marked than in animals managed on alfalfa hay in drylot. Incidence of ovulation approached zero in range-managed ewes during May, June, and July (8%, 0%, 4%) but was higher (P<0.05) in the alfalfa-drylot group (42%, 17%, 75%), respectively. Although the incidence remained lower (P<0.05) in August in range-managed than in drylot ewes (50% and 83%, respectively), both groups were ovulating at a high rate during September through January. Incidence of ovulation dropped dramatically both years in the range-managed group in February compared with that of the alfalfa-drylot group (48% and 36% vs 100% and 83%). Mean ovulation rate per ewe ovulating did not differ (P>0.10) between nutrition groups within the 14 months. Body weight was related to CL number during periods of seasonal transition only. Continuous or intermittent presence of a ram had no real effect on either incidence or rate of ovulation during the transitional months. Nutritional environment can affect seasonality of breeding in fine-wool range sheep. This effect may not be consistently modified by presence of rams.

Journal Article↗