Plaque-forming Cells Research Articles

The influence of opioids on the humoral and cell-mediated immune responses in mice. The role of macrophages

BackgroundOur experiments were aimed to test the influence of treatment with different opioids (morphine, fentanyl, methadone) on the humoral and cell-mediated immune responses. MethodsMice were treated intraperitoneally (ip) with opioids for several days and next either immunized with sheep red blood cells (SRBC) to test the antibody production or skin-sensitized with hapten picryl chloride (PCL) to induce contact hypersensitivity (CHS). In addition, the effects of opioids on the production of reactive oxygen intermediates (ROIs) and cytokines by peritoneal macrophages (Mf) and on the expression of surface markers on these cells and blood leukocytes were estimated. ResultsOpioids caused an enhancement of ROIs and cytokines production when macrophages were stimulated with zymosan or lipopolysaccharide (LPS) and reduced the expression of antigen presentation markers on Mf. Numbers of anti-SRBC plaque forming cells (PFC) and antibodies titres were lower in mice treated with all tested opioids. Depending on the use of particular opioid and the phase of allergic reaction, effects of the treatment on CHS were diverse. While morphine decreased the early and late phases of induction of CHS responses, methadone increased both reactions. In case of the effector phase of CHS, morphine and fentanyl increased both its early and late stages, while methadone decreased the late reaction. Treatment of recipients with opioids had diverse influence on the passive transfer of CHS in these animals. ConclusionsOur experiments show that the action of opioids on the immune system is a complex phenomenon dependent on such variables as type of opioid, character of response (humoral versus cellular) and types of cells involved. Here Mf seem to play a significant role.

Fermented milk supplemented with probiotics and prebiotics can effectively alter the intestinal microbiota and immunity of host animals

Fermented milk supplemented with 2 probiotic strains, Bifidobacterium lactis Bi-07 and Lactobacillus acidophilus NCFM, and a prebiotic, isomaltooligosaccharide, was orally administered to 100 healthy adults at 480g/d for 2 wk in a randomized controlled trial. The fecal bacterial compositions of these subjects were examined by culture before and after the intervention. The same fermented milk was also orally fed to BALB/c mice, and immune as well as fecal bacteria analyses were conducted using the same culturing methods. After the intervention, increases in fecal bifidobacteria and lactobacilli were observed among the subjects compared with the subjects in the control group. In contrast, after the intervention, fecal enterobacilli were significantly decreased in the test group compared with the control group. The same effects on the composition of the intestinal microbiota were observed in mice. Furthermore, the tested mice were found to have significantly increased delayed-type hypersensitivity, plaque-forming cells, and half-hemolysis values after the intervention with the fermented milk. In summary, the synbiotic fermented milk containing probiotics and a prebiotic may contribute to improve intestinal health and may have a positive effect on the humoral and cell-mediated immunity of host animals.

Immunotoxicologic assessment of genetically modified drought-resistant wheat T349 with GmDREB1

To assess the immunotoxicologic effects of genetically modified drought resistant wheat T349 with GmDREB1 gene. A total of 250 female BALB/c mice (6-8 week-old, weight 18-22 g) were divided into five large groups (50 mice for each large group) by body weight randomly. In each large group, the mice were divided into five groups (10 mice for each group) by body weight randomly, which were set as negative control group, common wheat group, parental wheat group, genetically modified wheat group and cyclophosphamide positive control group, respectively. Mice in negative control and positive control group were fed with feedstuff AIN-93G, mice in common wheat group, non-genetically modified parental wheat group and genetically modified wheat group were fed with feedstuffs added corresponding wheat (proportion up to 76%) for 30 days, then body weight, organ coefficient of spleen and thymus, peripheral blood lymphocytes phenotyping, serum cytokine, serum immunoglobulin, antibody plaque-forming cell (PFC), serum 50% hemolytic value (HC50), mitogen-induced splenocyte proliferation, delayed-type hypersensitivity (DTH) reaction and phagocytic activities of phagocytes were detected respectively. After 30 days raise, among negative control group, common wheat group, non-genetically modified parental wheat group, genetically modified wheat group and cyclophosphamide positive control group, mice body weight were (21.0±0.3), (20.4±0.7), (21.1±1.0), (21.1±1.0), (19.4±1.0) g, respectively (F=7.47, P<0.01); organ coefficient of spleen were (0.407±0.047)%, (0.390±0.028)%, (0.402±0.042)%, (0.421±0.041)%, (0.304±0.048)%, respectively (F=12.41, P<0.01); organ coefficient of thymus were (0.234±0.032)%, (0.246±0.028)%, (0.249±0.040)%, (0.234±0.034)%, (0.185±0.039)%, respectively (F=5.58, P<0.01); the percentage of T cell in peripheral blood were (70.43±4.44)%, (68.33±5.37)%, (73.04±2.68)%, (74.42±2.86)%, (90.42±1.66)%, respectively (F=57.51, P<0.01); the percentage of B cell were (13.89±3.19)%, (15.34±4.84)%, (13.06±4.22)%, (12.93±2.36)%, (3.01±0.96)%, respectively (F=12.79, P<0.01); the percentage of Th cell were (55.87±3.80)%, (55.24±4.60)%, (57.92±3.70)%, (59.57±2.54)%, (77.37±2.31)%, respectively (F=68.58, P<0.01);the Th/Ts ratio were 4.16±0.29, 4.73±0.96, 4.19±0.78, 4.52±0.40, 6.34±0.73, respectively (F=17.57, P<0.01);the serum IgG were (1046.38±210.67), (1065.49±297.22), (1517.73±299.52), (1576.67±241.92), (1155.88±167.05) µg/ml, respectively (F=10.53, P<0.01); the serum IgM were (333.83±18.97), (327.73±27.72), (367.47±27.18), (363.42±46.14), (278.71±24.42) µg/ml, respectively (F=12.11, P<0.01); the serum IgA were (51.69±10.10), (42.40 ± 8.35), (32.11±4.22), (37.12±4.90), (41.45±8.89) µg/ml, respectively (F=8.25, P<0.01); the PFC were (29.2±14.6), (28.0±20.0), (34.8±30.9), (33.2±25.1), (4.8±5.3) per 10(6) splenocyte, respectively (F=3.33, P<0.05); the HC50 were 82.3±6.5, 79.7±4.6, 75.8±4.1, 74.9±3.6, 70.8±2.1, respectively (F=9.99, P<0.01);the LPS-induced splenocyte proliferation were 0.21±0.10, 0.21±0.14, 0.26±0.12, 0.25±0.14, 0.07±0.06, respectively (F=4.18, P<0.05). The genetically modified drought-resistant wheat T349 was substantially equivalent to parental wheat in the effects on immune organs and immunologic functions of mice, and it didn't show immunotoxicity.

Evaluation of immunomodulatory activity of Glycyrhiza glabra L roots in combination with zing

ObjectiveTo determine the immunomodulatory properties of roots of Glycyrrhiza glabra (G. glabra) L. (Liquorice), and also to check whether significant potentiation in immunomodulation occurs or not with the combination of zinc. MethodsImmunomodulatory potential of aqueous liquorice extract (ALE) 0.75 and 1.5 g/kg BW and its combination with zinc (45 mg/kg BW) were determined by the effect on leukocyte count and spleen weight, In vivo phagocytosis (carbon clearance method), determination of cellular immune response, haemagglutination antibody titre and plaque forming cell (PFC) assay using sheep red blood cells (SRBC). In addition, the effect of the extract on Systemic Anaphylactic reaction was also measured. ResultsLeukocyte count and phagocytic index (carbon clearance) was increased significantly with the treatment of ALE (1.5 g/kg) compared to control (P <0.05). Zinc (45 mg/kg) in combination with ALE (0.75 g/kg) showed highly significant increase of leukocyte count and phagocytic index compared to control (P <0.01). Same groups also showed positive significant action on spleen weight. In cellular immune response study, an enhancement in foot pad thickness was observed when compared to control group. Neither of the two doses of ALE showed significant increase in HA titre value and antibody secreting cells of mouse spleen. However, combination of zinc (45 mg/kg) and ALE (0.750 g/kg) showed significant increase (P <0.05) in HA titre and antibody secreting cells of mouse spleen value compared to vehicle control. In systemic anaphylaxis reaction test, results indicate a positive effect on anaphylaxis with the treatment of ALE in both doses and in combination with zinc. ConclusionsThe present study has shown the immunomodulatory activity of aqueous root extract of G. glabra L. at the dose 1.5 g/kg BW. G. glabra L. in combination with zinc has shown potentiation of immunomodulatory activity in all aspects of the study.

Influence of betulinic acid on lymphocyte subsets and humoral immune response in mice

Betulinic acid is a pentacyclic triterpene found in many plant species, among others, in the bark of white birch Betula alba. Betulinic acid was reported to display a wide range of biological effects, including antiviral, antiparasitic, antibacterial, anticancer and anti-inflammatory activities. The effects of betulinic acid (50, 5, 0.5 mg/kg) administered orally five times at 24 hours intervals to non-immunized and red blood cells (SRBC)-immunized mice were determined. The present study examined the total number of lymphocytes in the thymus, spleen and mesenteric lymph nodes, and the percentage of subsets of T cells (CD4+CD8+, CD4CD8, CD4+, CD8+) in thymus,T (CD3+, CD4+, CD8+) and B (CD19+) lymphocytes in the spleen and mesenteric lymph nodes, as well as white blood cell (WBC) and differential leukocyte counts in non-immunized mice, and humoral immune response in SRBC-immunized mice. SRBC was injected 24 hours after administration of the last dose of betulinic acid. It was found that betulinic acid administered orally five times at the dose of 0.5 mg/kg increased the total number of thymocytes, splenocytes, lymphocytes of mesenteric lymph node cells, and the weight ratio of the spleen and mesenteric lymph nodes in non-immunized mice. Betulinic acid also changed the percentage of T cell subsets in the thymus and T and B lymphocytes in peripheral lymphatic organs. The effects of betulinic acid on T and B cell subpopulations depended on the dose applied. The strongest stimulating effect of betulinic acid was observed when the drug was administered at the dose of 0.5 mg/kg. Five exposures to betulinic acid (0.5 mg/kg) decreased the percentage of immature CD4+CD8+ thymic cells with corresponding increases in the percentage and absolute count of mature, single-positive CD4+ thymocytes and decreased the percentage and total count of CD3+ splenocytes and mesenteric lymph node cells with corresponding decreases in the percentage and absolute count of CD4+ and CD8+ cells. Multiple administration of betulinic acid at the investigated doses augmented the percentage and absolute count of CD19+ cells in the peripheral lymphatic organs. Moreover, betulinic acid at the dose of 5 mg/kg administered prior to SRBC immunization increased the number of plaque forming cells (PFC) but decreased the production of anti-SRBC antibodies on day 4 after priming. Thus, betulinic acid is a potential biological response modifier and may strengthen the immune response of its host.

Immunomodulatory Activities of Different Solvent Extracts from Tricholoma matsutake (S. Ito et S. Imai) Singer (Higher Basidiomycetes) on Normal Mice

The immunomodulatory activities of different solvent extracts from the culinary-medicinal mushroom Tricholoma matsutake were studied in vivo in normal mice. The extracts were prepared using different solvents in an order of increasing polarity. The immunomodulatory activities were investigated by measuring the thymus and spleen index, phagocytic rate of macrophage phagocytosis, delayed-type hypersensitivity, plaque-forming cell, and proliferation of splenocytes. Results demonstrated that water extract (WE) and n-butyl alcohol extract (BAE) of T. matsutake could enhance the immunity of mice significantly compared with the control group. Main components of WE and BAE were polysaccharides, proteins, and flavonoids; we presume that these may be the main immunomodulating and immuno-enhancing agents in T. matsutake.

Influence of peroral application of a herbal immunomodulator on the antibody production of Peyer's patches cells.

The influence of the peroral administration of the macromolecular components of a herbal immunomodulator isolated from an aqueous-ethanolic extract of the mixed herbal drugs Thujae summitates, Baptisiae tinctoriae radix, Echinaceae purpureae radix and Echinaceae pallidae radix on the function of Peyer's patches cells was investigated in mice. Peyer's patches cells isolated from mice which had received oral administration of the macromolecular fraction of the plant extract developed a significantly enhanced plaque-forming cell (PFC) response to sheep red blood cells after incubation with these cells in the presence of lipopolysaccharide or the extract fraction for 7 days in vitro. These results show that after oral administration of the herbal immunomodulator, the immunologically active macromolecules can contact the cells of the gut-associated lymphoid tissue and modulate the mucosal immune response.

Effects of Brx-019 (Acetic Acid 3,6a,9-triacetoxy-6,6a,7,11b-tetrahydro-indeno [2,1-c]chromen-10-yl Ester), a Brazilin Derivative, on T Cell-mediated Immune Responses in Multiple Low Dose Streptozo-tocin-induced Diabetic C57BL/6 Male Mice

Brx-019 (acetic acid 3,6a,9-triacetoxy-6, 6a,7,11b-tetrahydro-indeno [2,1-c] chromen-10-yl ester) was derived from brazilin (CAS 474-07-7) during a trial designed to search for immunomodulators with lower toxicity and more effective immunomodulating activities than brazilin. Brx-019 was selected as a potential immunomodulator based on its effects on Concanavalin A (Con A)-induced proliferation of splenocytes and the 3-[14,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay. Intraperitoneally administered Brx-019 significantly improved delayed type hypersensitivity and increased immunoglobulin M (IgM) plaque forming cells (PFCs) in multiple low dose streptozotocin-induced diabetic mice (MLDS-diabetic mice). This finding suggests that Brx-019 may increase suppressed humoral and cell-mediated immunity in type 1 diabetes. Brx-019 also significantly increased Con A- or alloantigen-induced proliferation of splenocytes, Con A-induced interleukin 2 (IL-2) production from splenocytes, and IL-2-induced proliferation of Con A-activated splenocytes in MLDS-diabetic mice. These results suggest that Brx-019 might improve immunity in diabetic mice by increasing IL-2 production in splenocytes and responsiveness of splenocytes to IL-2, which were suppressed in MLDS-diabetes.

Modulation of humoral immune responses and inhibition of proinflammatory cytokines and nitric oxide production by 10-methoxycanthin-6-one

Plant-derived natural products such as alkaloids, flavonoids, terpenoids, and polysaccharides have received considerable attention in recent years due to their diverse pharmacological properties such as immunomodulatory, anti-inflammatory, cytotoxic, cancer chemopreventive effects, and so on. 10-Methoxycanthin-6-one, a β-carboline alkaloid from the medicinal plant Aerva lanata, was assessed for immunomodulatory activity in Balb/c mice. Intraperitoneal administration of five doses of the compound at 0.5 mg/kg body weight was found to enhance the total WBC count (13,975.50 ± 324.27 cells/mm3 on the 12th day), bone marrow cellularity (23.08 ± 0.86 × 106 cells/femur), and number of α-esterase-positive cells (1283.16 ± 21.10 cells/4000 cells). Treatment with the compound along with the antigen, sheep red blood cells, produced an enhancement in the circulating antibody titer (1024 on Days 12 and 15) and the number of plaque-forming cells (PFC) in the spleen. In treated group, maximum number of PFC (264.83 PFC/106 spleen cells) was observed on the sixth day after antigen administration. At the same time, administration of 10-methoxycanthin-6-one could significantly reduce the elevated levels of proinflammatory cytokines and nitric oxide production by lipopolysaccharide (LPS)-stimulated macrophages. There was also a significant reduction in the mRNA levels of inducible nitric oxide synthase, cyclooxygenase 2, tumor necrosis factor alpha (TNF)-α, and interleukin (IL)-1β and IL-6 in LPS-stimulated macrophages after treatment with 10-methoxycanthin-6-one.

Germinal Center Texture Entropy as Possible Indicator of Humoral Immune Response: Immunophysiology Viewpoint

In this article, we present the results indicating that spleen germinal center (GC) texture entropy determined by gray-level co-occurrence matrix (GLCM) method is related to humoral immune response. Spleen tissue was obtained from eight outbred male short-haired guinea pigs previously immunized by sheep red blood cells (SRBC). A total of 312 images from 39 germinal centers (156 GC light zone images and 156 GC dark zone images) were acquired and analyzed by GLCM method. Angular second moment, contrast, correlation, entropy, and inverse difference moment were calculated for each image. Humoral immune response to SRBC was measured using T cell-dependent antibody response (TDAR) assay. Statistically highly significant negative correlation was detected between light zone entropy and the number of TDAR plaque-forming cells (r (s) = -0.86, p < 0.01). The entropy decreased as the plaque-forming cells increased and vice versa. A statistically significant negative correlation was also detected between dark zone entropy values and the number of plaque-forming cells (r (s) = -0.69, p < 0.05). Germinal center texture entropy may be a powerful indicator of humoral immune response. This study is one of the first to point out the potential scientific value of GLCM image texture analysis in lymphoid tissue cytoarchitecture evaluation. Lymphoid tissue texture analysis could become an important and affordable addition to the conventional immunophysiology techniques.

Potential Immunotoxicological Health Effects Following Exposure to COREXIT 9500A during Cleanup of the Deepwater Horizon Oil Spill

Workers involved in the Deepwater Horizon oil spill cleanup efforts reported acute pulmonary and dermatological adverse health effects. These studies were undertaken to assess the immunotoxicity of COREXIT 9500A, the primary dispersant used in cleanup efforts, as a potential causative agent. COREXIT 9500A and one of its active ingredients, dioctyl sodium sulfosuccinate (DSS), were evaluated using murine models for hypersensitivity and immune suppression, including the local lymph node assay (LLNA), phenotypic analysis of draining lymph node cells (DLN), mouse ear swelling test (MEST), total serum immunoglobulin E (IgE), and the plaque-forming cell (PFC) assay. Dermal exposure to COREXIT 9500A and DSS induced dose-responsive increases in dermal irritation and lymphocyte proliferation. The EC3 values for COREXIT 9500A and DSS were 0.4% and 3.9%, respectively, resulting in a classification of COREXIT 9500A as a potent sensitizer and DSS as a moderate sensitizer. A T-cell-mediated mechanism underlying the LLNA was supported by positive responses in the MEST assay for COREXIT and DSS, indicated by a significant increase in ear swelling 48 h post challenge. There were no marked alterations in total serum IgE or B220+/IgE+ lymph-node cell populations following exposure to COREXIT 9500A. Significant elevations in interferon (IFN)-γ but not interleukin (IL)-4 protein were also observed in stimulated lymph node cells. The absence of increases in IgE and IL-4 in the presence of enhanced lymphocyte proliferation, positive MEST responses, and elevations in IFN-γ suggest a T-cell-mediated mechanism. COREXIT 9500A did not induce immunosuppression in the murine model.

Immunotoxicity of Copper Alginate Fibers in Guinea Pigs and Mice

The relation between copper alginate fibers and immunotoxicity in animals was studied by dividing guinea pigs and mice into control groups and experimental groups. Varied weights of fibers were subcutaneously embedded in the experimental groups, whereas the control groups were operated on simulatively. Morphology analysis, erythrocyte osmotic fragility (EOF) test, direct plaque-forming cell (PFC) assay, quantitative hemolysis spectrophotometry (QHS) assay, macrophages phagocytosis assay, and pathology analysis were used to examine morphology, microstructure, and immunotoxicity. With increasing doses of copper alginate fibers, the EOF of experimental groups increased in contrast with the control group. Moreover, the antibody level decreased based on the results of the PFC and QHS assays, and macrophages phagocytosis descended in relation to dose. However, the immune functions were weakened without time dependence. According to pathologic photographs, the partial organs were damaged, implying bad histocompatibility. Hence, copper alginate fiber is proved to be a harmful material for medical devices.

In vitro immunomodulation effects of the aqueous and protein extracts of Berberis hispanica Boiss and Reut. (Family Berberidaceae)

Immunomodulatory activities of aqueous and protein extracts of Berberis hispanica were evaluated in vitro. Both extracts at 1 mg/ml showed no cytotoxicity effect on thymocytes, splenocytes and macrophages cells. These extracts strongly inhibited in vitro the mitogen proliferative response of thymocyte and spleen cells. Humoral immunity measured by plaque-forming cell assay and evolution of complement activity showed an increase of plaque-forming cell formed and complement activity after addition of protein extract, where aqueous extract induced a significant diminution only in plaque-forming cell. In addition, the same extracts elicited a significant decrease in phagocytic capacity without affecting macrophage cells viability. In the allogenic mixed lymphocyte reaction test, plant extracts mainly increased lymphocyte cytotoxic activity towards chicken red bloods cells. The present data support that Berberis hispanica extracts showed an immunosuppressive action on proliferation and biological effects of T-cell and B-cell. This suggests a possible use of aqueous extract in auto-immune diseases therapy. However, the protein extract, highly stimulates allogenic mixed lymphocyte which suggest an interesting use in cancer therapy. Key words: Berberis hispanica, immunomodulation, plaque-forming cell, allogenic mixed lymphocyte phagocytosis.

Effect of chloroquine and some other antimalarials on the immune mechanism in experimental animals.

The effects of chloroquine and some other antimalarials on the immune responses in experimental animals have been examined. Chloroquine and quinine caused significant decrease of serum anti-SRBC haemagglutination titre. Chloroquine lowered the serum IgM level and also reduced plaque-forming cells in the spleen of mice. The delayed-type hypersensitivity responses to SRBC and the passive cutaneous anaphylaxis were also diminished in rats treated with chloroquine. Thus, the immunosuppressant activity of chloroquine may explain its efficacy in various types of immune disorders.

Alterations in immune function and CYP450 activity of adult male deer mice following exposure to either 7,12-dimethylbenz[a]anthracene or benzo[b]fluoranthene

Adult male deer mice were exposed every other day for a period of 11 days to either 7,12-dimethylbenzanthracene (DMBA; CAS# 57-97-6) or benzo[b]fluoranthene (BbF; CAS# 205-99-2) (0, 0.3, 1, 3, 10, or 30 mg kg−1). Immune endpoints assessed were lymphocyte proliferation, macrophage pinocytosis, and the antibody plaque-forming cell (PFC) response. Cytochrome P450 (CYP450) activity was assessed using ethoxyresorufin-O-deethylase (EROD) and pentoxyresorufin-O-deethylase (PROD). Macrophage pinocytosis was not altered by either compound. Both T- and B-cell proliferations were significantly increased by DMBA at 0.3 or 1 mg kg−1 and by BbF at 10 or 30 mg kg−1, but decreased by DMBA at 30 mg kg−1. Sheep red blood cell (SRBC)-specific-IgM production, as measured by the PFC response, was the most striking adverse immune effect observed and was significantly suppressed compared to control at all treatment concentrations for both compounds. EROD activity was markedly induced by DMBA at 30 mg kg−1, while BbF produced induction at 1, 10, or 30 mg kg−1. No marked effect on PROD activity was noted following DMBA treatment, but BbF-induced PROD activity at 1, 10, or 30 mg kg−1. Unexpectedly, four of six mice in the 30 mg DMBA kg−1 group did not survive to the end of the experiment, and one animal died in both the 3 and 10 mg kg−1 treatments. The calculated LD50 was 20.8 mg DMBA kg−1. The PFC response in deer mice was a more sensitive endpoint than CYP450 activity, suggesting that utilization of CYP450 endpoints in risk assessment without assessment of immune function, specifically antibody production, might possibly underestimate the risk to wild rodents environmentally exposed to polycyclic aromatic hydrocarbons.

Tributyltin chloride-induced immunotoxicity and thymocyte apoptosis are related to abnormal Fas expression

Tributyltin chloride (TBTC), a characteristic organotin compound, is widely used as an agricultural pesticide, as a stabiliser for polyvinyl-chloride plastics and in antifouling paints for ship hulls. Organotin compounds are known to produce toxicity in the immune system, but the mechanism underlying this immunotoxicity remains unclear. In this study, we evaluated the immunotoxic effect of TBTC on the acquired immune response, and we investigated the involvement of thymocyte apoptosis and Fas expression in the observed immunotoxicity of TBTC. Mice were randomly assigned to four groups (10 mice per group) and treated with TBTC at doses of 0, 0.5, 4 and 20 mg/kg by oral gavage for 28 days. Following TBTC administration, animals were sacrificed, and morphologic changes in the thymus and spleen were assessed. Atrophy in both the thymus and spleen was observed in all groups treated with TBTC, and the relative organ weight in the highest TBTC group (20 mg/kg) was significantly lower than that observed in the control group. We also conducted assays to assess the cellular and humoral functional responses such as plaque-forming cell assay (PFC), lymphocyte proliferation test and delayed-type hypersensitivity (DTH) response to SRBC. Our results indicate that at doses of 4 mg/kg and 20 mg/kg, TBTC could significantly suppress both the humoral and cellular immune responses when compared to the control group (p<0.05). In addition, immunohistochemical staining and flow cytometry analysis were carried out to measure the expression of Fas and thymocyte apoptosis, respectively. We observed a dose-dependent increase in thymocyte apoptosis and that Fas expression in the TBTC-treated groups (4 mg/kg and 20 mg/kg) was significantly enhanced when compared to the control group. Correlation analysis demonstrated a positive linear correlation between apoptosis and Fas expression, indicating that TBTC-induced thymocyte apoptosis may be mediated by Fas expression. Taken together, our data clearly demonstrate that TBTC-induced immunotoxicity is associated with thymocyte apoptosis and that this process is mediated by the Fas pathway.

The effects of florfenicol on lymphocyte subsets and humoral immune response in mice

Florfenicol is a broad-spectrum bacteriostatic antibiotic used in domestic animals. The aim of the study was to determine the effect of florfenicol on the total number of lymphocytes in the thymus, spleen and mesenteric lymph nodes and the percentage and the absolute number of T cell subsets (CD4+CD8+, CD4-CD8-, CD4+, CD8+) in the thymus and T (CD3+, CD4+, CD8+) and B (CD19+) lymphocytes in the peripheral lymphatic organs in non-immunized mice and humoral immune response in sheep red blood cells (SRBC)-immunized mice. Florfenicol was administered orally at a dose of 30 mg/kg six times at 24 h intervals to non-immunized mice and four or seven times at 24 h intervals to SRBC-immunized mice. SRBC was injected 2 hours prior to the first dose of the drug. Florfenicol increased the percentage of CD4CD8- thymocytes and the absolute number of CD4+ and CD8+ thymocytes on day 7. The increased percentage and absolute number of CD3+, CD4+ and CD8+ lymphocytes in mesenteric lymph nodes and decreased percentage of lymphocytes B were also observed 24 hours from the last administration of florfenicol. Florfenicol administered after SRBC immunization reduced the number of plaque forming cells (PFC) and the production of anti-SRBC antibodies on days 4 and 7 after priming.

Immunomodulatory and antitumor activity of Aerva lanata ethanolic extract

Cancer is responsible for millions of deaths each year worldwide. Pharmacological intervention with plant-derived products alone or in combination to reverse, suppress, or prevent the cancer progression plays a key role in the fight against this terrible disease. Aerva lanata is an important medicinal plant widely used in traditional systems of medicine like ayurveda and siddha. Ethanolic extract of whole plant of A. lanata exhibited immunomodulatory and antitumor activity. Intraperitoneal administration of five doses of the extract (10 mg/kg body weight) was found to enhance the total WBC count (14,238 cells/mm3), bone marrow cellularity (22.33 × 106 cells/femur), and number of α-esterase-positive cells (1276 cells/4000 cells). Aerva treatment also showed enhanced proliferation of splenocytes, thymocytes, and bone marrow cells both in the presence and absence of specific mitogens in vitro and in vivo. The number of plaque-forming cells (PFC) in spleen (243.33 PFC/106 spleen cells) and circulating antibody titer were also increased (P < 0.001). The extract was 100% cytotoxic to Dalton’s lymphoma ascites (DLA) and Ehrlich ascites carcinoma (EAC) cells at a concentration of 500 µg/mL. It was also found to be cytotoxic toward L929 and HELA cells at higher concentrations, whereas the nontoxic concentrations produced a reduction in the rate of proliferation. Simultaneous administration of five doses of A. lanata extract could produce significant inhibition in DLA-induced solid tumor development in mice and increase the life span of mice-bearing EAC tumors by 53.47%.

Isolation, Characterization, and Immunological Effects of α-Galacto-oligosaccharides from a New Source, the Herb Lycopus lucidus Turcz.

This study was designed to isolate and characterize a mixture of alpha-galacto-oligosaccharides (GOS) from a new source, the roots of Lycopus lucidus Turcz. (RL), a traditional dietary treatment. In this study, the chemical components and immunological function of RL-GOS were investigated. HPLC analysis showed that the purified RL-GOS was a typical raffinose family oligosaccharide (RFO) with a high stachyose content of 51.8% (w/w), followed by 26.5% raffinose and 10.1% verbascose. Further functional evaluation showed that RL-GOS could elicit a significant increase (p < 0.05 vs control) in humoral immunity, as measured by plaque-forming cell (PFC) generation and serum hemolysin level in response to sheep red blood cells (SRBC) at all three tested doses of RL-GOS (0.75, 1.5, and 3.0 g/kg of BW) in mice. In addition, the cellular immune activity of RL-GOS was also demonstrated by enhancing in vivo delayed-type hypersensitivity (DTH) reaction to SRBC and spleenocyte proliferation response to concanavalin A (p < 0.05, compared with control group). Nevertheless, there were no significant differences in weight gain, lymphoid organ indices, and phagocytosis capacity following RL-GOS treatment. This study provides evidence for the discovery of a new GOS source (20% w/w GOS in fresh roots of L. lucidus Turcz.) and its potential application as an immune stimulant in functional foods.

Arctigenin, a phenylpropanoid dibenzylbutyrolactone lignan, inhibits type I–IV allergic inflammation and pro-inflammatory enzymes

We previously reported that arctigenin, a phenylpropanoid dibenzylbutyrolactone lignan isolated from Forsythia koreana, exhibits anti-inflammatory, antioxidant, and analgesic effects in animal models. In addition, arctigenin inhibited eosinophil peroxidase and activated myeloperoxidase in inflamed tissues. In this study, we tested the effects of arctigenin on type I-IV allergic inflammation and pro-inflammatory enzymes in vitro and in vivo. Arctigenin significantly inhibited the heterologous passive cutaneous anaphylaxis induced by ovalbumin in mice at 15 mg/kg, p.o., and compound 48/80-induced histamine release from rat peritoneal mast cells at 10 microM. Arctigenin (15 mg/kg, p.o.) significantly inhibited reversed cutaneous anaphylaxis. Further, arctigenin (15 mg/kg, p.o.) significantly inhibited the Arthus reaction to sheep's red blood cells, decreasing the hemolysis titer, the hemagglutination titer, and the plaque-forming cell number for SRBCs. In addition, arctigenin significantly inhibited delayed type hypersensitivity at 15 mg/kg, p.o. and the formation of rosette-forming cells at 45 mg/kg, p.o. Contact dermatitis induced by picrylchloride and dinitrofluorobenzene was significantly (p < 0.05) inhibited by surface treatment with arctigenin (0.3 mg/ear). Furthermore, arctigenin dose-dependently inhibited pro-inflammatory enzymes, such as cyclooxygenase-1 and 2, 5-lipoxygenase, phospholipase A2, and phosphodiesterase. Our results show that arctigenin significantly inhibited B- and T-cell mediated allergic inflammation as well as pro-inflammatory enzymes.