Phagocytic Function Of Macrophages Research Articles

Chemical Composition and Immunomodulatory Activity of Mycelia of the Hairy Bracket Mushroom, Trametes hirsuta (Higher Basidiomycetes).

Trametes hirsuta is a medicinal mushroom that produces laccase. Its mycelium is a by-product when this species is used for laccase production. Aiming to develop its potential medicinal value, we investigated the chemical composition and immunomodulatory activity of T. hirsuta mycelia (THM). Dried THM contained 26.06% protein, 1.15% fat, 57.87% carbohydrates, and 5.47% ash. Sixteen free amino acids (2.63% total content) and 6 5'-nucleotides (adenosine 5'-monophosphate, cytidine 5'-monophosphate, guanosine 5'-monophosphate, uridine 5'-monophosphate, xanthosine 5'-monophosphate, and inosine 5'-monophosphate) constituting 0.275% were detected. Dominant sugars and polyols were fructose (2.47%), mannitol (2.03%), and glucose (1.8%); trehalose and arabinose contents were less than 0.10%. Evaluation of immunomodulatory activity in mice showed that THM could improve macrophage phagocytic function and serum hemolysin concentrations, but only the low-dose group significantly enhanced the natural killer cell activity and increased the spleen index, and only the middle-dose group remarkably increased the thymus index. Therefore, T. hirsuta mycelia could enhance immune function in mice and have immunomodulatory activity.

In Vitro Macrophage Phagocytosis Assay.

The key roles of macrophages in atherosclerosis include the phagocytosis of apoptotic and necrotic cells and cell debris, whose accumulation in atherosclerotic lesions exacerbates inflammation and promotes plaque vulnerability. Evidence is accumulating that macrophage phagocytic functions peak at the early stages of atherosclerosis and that the reduced phagocytosis at the late stages of disease leads to the generation of necrotic cores and a defective resolution of inflammation, which in turn promotes plaque rupture, thrombus formation, and life-threatening acute ischemic events (myocardial infarction and stroke). The impaired resolution of inflammation in advanced lesions featuring loss of macrophage phagocytic activity may be in part due to an imbalance between M1 and M2 subsets of polarized macrophages. A better understanding of the mechanisms that regulate macrophage phagocytic activity in the context of atherosclerosis may therefore help identify novel therapeutic targets. This chapter presents a protocol for establishing primary mouse macrophage cultures, a method for polarizing macrophages to the M1 and M2 states, and a method for the in vitro study of macrophage phagocytosis of IgG-opsonized or IgM/complement component 3-opsonized erythrocytes.

Phagocytic Function of Macrophages Is Impaired By Chronic Lymphocytic Leukemia and high–grade Lymphoma Progression and Can be Highly Effectively Restored for Chemo-Immunotherapy

Macrophage polarity has recently been shown to play a pivotal role in progression and prognosis of human malignancies. In CLL the high dependence of the malignant cell to the tumor microenvironment has revealed macrophages as major mediators of leukemia cell survival. In contrast, macrophage activation also offers novel therapeutic strategies for leukemia cell targeting. Here we analyze the reciprocal relationship of leukemia cells and macrophages and the specific functional impact of phagocytosis in leukemia progression and therapy.We employed the humanized hMB-Lymphoma and the Eµ-TCL1 CLL mouse model. Thioglycollate-induced macrophages, bone marrow derived murine macrophages and human monocyte derived macrophages were used for in vitroevaluation of phagocytosis either by bead based approaches or by ADCC.Applying gene-expression profiling of macrophages in Eµ-TCL1 mice we could identify profound transcriptional alterations indicating a re-programming during leukemogenesis. Functional genomic analysis particularly revealed impaired phagocytic function induced during leukemia onset. In vivo and ex vivo phagocytosis assays of primary macrophages showed a significant reduced phagocytic activity during CLL progression. Human macrophages in co-culture with CLL cells in vitro compared to healthy B-cells similarly showed defects in phagocytosis. In the humanized leukemia model we similarly observed impaired phagocytosis resulting in resistance towards therapeutic antibody/macrophage mediated therapy. Resistance was actively induced by increasing leukemia cell infiltration in the bone marrow. Impaired macrophage function could be identified being mediated by secretory crosstalk such as release of PGE2 by leukemia cells and Cholecalciferol. We could restore phagocytic function by combination regimens involving therapeutic antibodies and chemotherapy. Specifically, an acute secretory activating phenotype (ASAP), releasing cytokines from leukemia cells induces macrophage infiltration and phagocytic activity in the bone marrow. Thus, malignant cells can be effectively targeted by modulation of macrophage polarization and function.In conclusion, we have identified decreased phagocytic activity of macrophages as key functional aspect in leukemia and lymphoma associated macrophages. Inversely, enhancing phagocytosis rendered essential for the re-sensitization of refractory niches treatment towards monoclonal antibodies defined by macrophage polarity. Overall macrophage function represents a key therapeutic target in CLL and other B-cell malignancies. DisclosuresNo relevant conflicts of interest to declare.

Malondialdehyde-Acetaldehyde (MAA) adducted surfactant protein alters lung macrophage inflammatory and phagocytic functions

Malondialdehyde-Acetaldehyde (MAA) adducted surfactant protein alters lung macrophage inflammatory and phagocytic functions

Oxidative stress decreases functional airway mannose binding lectin in COPD.

We have previously established that a defect in the ability of alveolar macrophages (AM) to phagocytose apoptotic cells (efferocytosis) and pathogens is a potential therapeutic target in COPD. We further showed that levels of mannose binding lectin (MBL; required for effective macrophage phagocytic function) were reduced in the airways but not circulation of COPD patients. We hypothesized that increased oxidative stress in the airway could be a cause for such disturbances. We therefore studied the effects of oxidation on the structure of the MBL molecule and its functional interactions with macrophages. Oligomeric structure of plasma derived MBL (pdMBL) before and after oxidation (oxMBL) with 2,2′-azobis(2-methylpropionamidine)dihydrochroride (AAPH) was investigated by blue native PAGE. Macrophage function in the presence of pd/oxMBL was assessed by measuring efferocytosis, phagocytosis of non-typeable Haemophilus influenzae (NTHi) and expression of macrophage scavenger receptors. Oxidation disrupted higher order MBL oligomers. This was associated with changed macrophage function evident by a significantly reduced capacity to phagocytose apoptotic cells and NTHi in the presence of oxMBL vs pdMBL (eg, NTHi by 55.9 and 27.0% respectively). Interestingly, oxidation of MBL significantly reduced macrophage phagocytic ability to below control levels. Flow cytometry and immunofluorescence revealed a significant increase in expression of macrophage scavenger receptor (SRA1) in the presence of pdMBL that was abrogated in the presence of oxMBL. We show the pulmonary macrophage dysfunction in COPD may at least partially result from an oxidative stress-induced effect on MBL, and identify a further potential therapeutic strategy for this debilitating disease.

Identification of B7-H1 as a Novel Mediator of the Innate Immune/Proinflammatory Response as well as a Possible Myeloid Cell Prognostic Biomarker in Sepsis

Identifying relevant mediators responsible for the pathogenesis during sepsis may lead to finding novel diagnostic and therapeutic targets. Recent studies indicate programmed cell death receptor (PD)-1 plays a significant role in the development of immune suppression associated with sepsis. In this study, we determine whether B7-H1, the primary ligand of PD-1, contributes to the pathogenesis of sepsis. We report that B7-H1 is upregulated extensively on various immune cells during sepsis and B7-H1 gene deficiency protects mice from the lethality of sepsis. In terms of the histological development of multiple organ damage and inflammatory cytokine levels in circulation or at infectious site, B7-H1-deficient mice showed a remarkable reduction in these indices when compared with wild-type mice. However, B7-H1 gene-deficient mice did not exhibit a lower bacterial burden when compared with wild-type mice, although they recruited more macrophages and neutrophils into infectious site. In addition, we found that, during sepsis, whereas there were no marked differences affecting ex vivo macrophage cytokine productive capacity between PD-1 and B7-H1 gene-deficient mice, preservation of ex vivo macrophage phagocytic function was only seen in septic PD-1 knockout mouse cells. Finally, higher percentage B7-H1(+) neutrophils in peripheral blood correlated not only with higher levels of pro- and anti-inflammatory cytokines/chemokines (CCL2, IL-6, CXCL2, KC, TNF-α, and IL-10), but with lethal outcome as well. Together, these results indicate B7-H1 contributes to septic morbidity in fashion distinct from PD-1 and suggest B7-H1 expression on neutrophils could be used as a biomarker of septic severity.

Effects of pristane alone or combined with chloroquine on macrophage activation, oxidative stress, and TH1/TH2 skewness.

We investigated the protective role of chloroquine against pristane-induced macrophage activation, oxidative stress, and Th1/Th2 skewness in C57BL/6J mice. Those mice were treated with pristane alone or combined with chloroquine. Hematological and biochemical parameters, macrophage phagocytic function, the oxidant/antioxidant index, cytokine for IFN-γ, TNF-α, IL-4, and IL-6, and the isotypes of IgG2a and IgG1 were determined. And the expression of T-bet/GATA-3 and IL-12/IL-10 mRNA in spleen were analyzed by real-time PCR. We found that pristane treatment for a period of 12 or 24 weeks triggered macrophage activation syndrome, characterized by hemophagocytosis in spleen and peripheral blood, enhanced lipid phagocytosis by peritoneal macrophages in vitro, erythropenia and leucopenia, increased anti-Smith, lactic dehydrogenase, triglyceride, and ferritin, as well as hypercytokinemia of IFN-γ, TNF-α, IL-4, and IL-6. In parallel, a significant increase in lipid peroxidation and a decrease in superoxide dismutase, glutathione, and catalase activity, as well as a skewed Th1/Th2 balance in spleen, were observed. However, chloroquine supplementation showed a remarkable amelioration of these abnormalities. Our data indicate that pristane administration induces macrophage activation, oxidative stress, and Th1/Th2 skewness, which can be attenuated by chloroquine.

Inhibitive effect on phagocytosis of Candida albicans induced by pretreatment with quercetin via actin cytoskeleton interference

ObjectiveTo investigate the anti-inflammatory effect of pretreatment with quercetin on macrophages after Candida albicans infection. MethodsRAW 264.7 macrophages were used as a target cell line. Cell viability after treatment with quercetin at different time points was detected by Carboxyfluorescein diacetate, succinimidyl ester. Phagocytic function of macrophages was determined by a fluorometric assay. Cytokine tumor necrosis factor α (TNF-α) production was measured by enzyme-linked immunosorbent assay. F-actin cytoskeleton of L929 cells was stained by Alexa Fluor® 488-phalloidin. ResultsPretreatment with quercetin decreased cell viability only at the highest concentration of 37 µg/mL 2, 24, and 48 h after the treatment. The phagocytic efficiency of macrophages pretreated with quercetin was significantly decreased in a time- and dose-dependent manner. F-actin labeling showed that the actin cytoskeleton of the cells started to break down 2 h after treatment. Moreover, it notably inhibited cytokine TNF-α production after Candida albicans infection. ConclusionPretreatment with quercetin induced an anti-inflammatory effect against Candida albicans infection in macrophages.

Sterols and oxysterols in immune cell function

Intermediates in the cholesterol-biosynthetic pathway and oxysterol derivatives of cholesterol regulate diverse cellular processes. Recent studies have expanded the appreciation of their roles in controlling the functions of cells of the innate and adaptive immune systems. Here we review recent literature reporting on the biological functions of sterol intermediates and oxysterols, acting through transcription factors such as the liver X receptors (LXRs), sterol regulatory element-binding proteins (SREBPs) and the G protein-coupled receptor EBI2, in regulating the differentiation and population expansion of cells of the innate and adaptive immune systems, their responses to inflammatory mediators, their effects on the phagocytic functions of macrophages and their effects on antiviral activities and the migration of immune cells. Such findings have raised many new questions about the production of endogenous bioactive sterols and oxysterols and their mechanisms of action in the immune system.

Inflammatory Mechanisms in Sepsis

Invariant natural killer T cells (iNKT) cells are emerging as key mediators of innate immune cellular and inflammatory responses to sepsis and peritonitis. Invariant natural killer T cells mediate survival following murine septic shock. Macrophages are pivotal to survival following sepsis. Invariant natural killer T cells have been shown to modulate various mediators of the innate immune system, including macrophages. We demonstrate sepsis-inducing iNKT-cell exodus from the liver appearing in the peritoneal cavity, the source of the sepsis. This migration was affected by programmed death receptor 1. Programmed death receptor 1 is an inhibitory immune receptor, reported as ubiquitously expressed at low levels on iNKT cells. Programmed death receptor 1 has been associated with markers of human critical illness. Programmed death receptor 1-deficient iNKT cells failed to demonstrate similar migration. To the extent that iNKT cells affected peritoneal macrophage function, we assessed peritoneal macrophages' ability to phagocytose bacteria. Invariant natural killer T(-/-) mice displayed dysfunctional macrophage phagocytosis and altered peritoneal bacterial load. This dysfunction was reversed when peritoneal macrophages from iNKT(-/-) mice were cocultured with wild-type iNKT cells. Together, our results indicate that sepsis induces liver iNKT-cell exodus into the peritoneal cavity mediated by programmed death receptor 1, and these peritoneal iNKT cells appear critical to regulation of peritoneal macrophage phagocytic function. Invariant natural killer T cells offer therapeutic targets for modulating immune responses and detrimental effects of sepsis.

Crude Dietary Polysaccharide Fraction Isolated from Jackfruit Enhances Immune System Activity in Mice

Crude polysaccharides (PSs) were isolated from the fruit pulp of jackfruit, and their chemical composition determined and evaluated for an immune regulatory activity in mice. The PSs were isolated from water extracts of jackfruit pulp (JFP) using the ethanol precipitation method. The resulting precipitates were further purified by dialysis and protein depletion by the Sevage method. The phenol-sulfuric method was used to determine the content of the PSs. The composition of PSs was determined by the Sephadex-G200 column chromatography and high-performance liquid chromatography methods. The thymus index and macrophage phagocytic function methods in mice were used to evaluate the immune regulatory activity of JFP-PSs. The JFP-PSs content in jackfruit was about 21% (w/w) and the yield of crude PSs was 3.91%. The single molecular mass weight PS was the main constituent of JFP-PSs. The major monosaccharide residues were rhamnose, glucose, galactose, and arabinose. The JFP-PSs enhanced the thymus weight index and the phagocytic rate after 30 days of subchronic p.o. administration to mice at 4.5 mg/kg. The JFP contains single molecular PS and JFP-PS has immune-stimulating activities in mice. These data suggest that at least some of the traditional uses of JFP can be ascribed to its immunomodulatory effects.

Myeloid expression of co‐inhibitory receptor ligand, B7‐H1, as a novel biomarker/mediator of septic progression/ morbidity

Recent studies indicate programmed cell death receptor (PD)‐1 plays a significant role in the development of immune suppression associated with sepsis. However, while PD‐1 is reported to interact with two cell surface ligands B7‐H1 and B7‐DC, it is not clear what their role to septic morbidity may be. Here we determine if B7‐H1 contributes to the pathogenesis of sepsis. We report that B7‐H1 is up‐regulated extensively on various immune cells during sepsis and B7‐H1 gene deficiency protected mice from the lethality of sepsis. In terms of histological development of multiple organ damage and inflammatory cytokine levels in circulation or at infectious site, B7‐H1 deficient mice showed a reduction in these indices when compared with WT mice. However, B7‐H1 gene deficiency did not alter bacterial burden when compared to WT mice. In addition, we found that, during sepsis, while there were no marked differences affecting ex vivo macrophage cytokine productive capacity between PD‐1 and B7‐H1 gene deficient mice; preservation of ex vivo macrophage phagocytic function was only seen in septic PD‐1 knockout mice cells. Finally, higher % B7‐H1+ neutrophils in peripheral blood was correlated with lethal outcome. Together, these results indicate B7‐H1 expression contributes to septic morbidity and suggest B7‐H1 on neutrophils could be used as a biomarker to indicate the severity of sepsis.

The effect-enhancing and toxicity-reducing activity of Hypericum japonicum Thunb. extract in murine liver cancer chemotherapy

Chinese herbs are potential sources of antitumor drugs with immunoregulatory activity and few adverse effects. In the present study, we investigated whether the Hypericum japonicum Thunb. (HJT) extract enhanced the efficacy of 5-fluorouracil (5-FU) treatment in murine liver tumor xenografts and reduced toxicity of chemotherapy in hepatoma H22-bearing mice. Tumor weight and inhibition rate, thymus and spleen indices, as well as white blood cell (WBC) count were calculated. The phagocytic function of macrophages was assessed by observing peritoneal macrophages phagocytized chicken red blood cells (RBC). Body weight and toxic reactions of the chemotherapeutic and life prolongation rate were investigated in the mice. Results demonstrated that the HJT extract significantly enhanced the tumor inhibition rate of 5-FU, improved the immune function, reduced the toxic effects and prolonged the survival time in the tumor-bearing mice. Taken together, these results indicated that the HJT extract has a synergistic tumor-inhibiting effect with 5-FU, is able to reduce the toxic side effects and is likely to be safe and efficacious for use in antitumor therapy.

Syntaxin 11 is required for NK and CD8+ T‐cell cytotoxicity and neutrophil degranulation

Syntaxin 11 (STX11) controls vesicular trafficking and is a key player in exocytosis. Since Stx11 mutations are causally associated with a familial hemophagocytic lymphohistio-cytosis, we wanted to clarify whether STX11 is functionally important for key immune cell populations. This was studied in primary cells obtained from newly generated Stx11(-/-) mice. Our data revealed that STX11 is not only widely expressed in different immune cells, but also induced upon LPS or IFN-γ treatment. However, Stx11 deficiency does not affect macrophage phagocytic function and cytokine secretion, mast cell activation, or antigen presentation by DCs. Instead, STX11 selectively controls lymphocyte cytotoxicity in NK and activated CD8(+) T cells and degranulation in neutrophils. Stx11(-/-) NK cells and CTLs show impaired degranulation, despite a comparable activation, maturation and expression of the complex-forming partners MUNC18-2 and VTI1B. In addition, Stx11(-/-) CTLs and NK cells produce abnormal levels of IFN-γ. Since functional reconstitution rescues the defective phenotype of Stx11(-/-) CTLs, we suggest a direct, specific and key role of STX11 in controlling lymphocyte cytotoxicity, cytokine production and secretion. Finally, we show that these mice are a very useful tool for dissecting the role of STX11 in vesicular trafficking and secretion.

Immunomodulatory Effect of Ganoderma Lucidum Polysaccharides (GLP) on Long-Term Heavy-Load Exercising Mice

Long-term heavy-load exercise can lead to a decrease in the organism's immune response. In this study, we used 100 Kunming (KM) mice to investigate the immune-regulatory effects of Ganoderma lucidum polysaccharides (GLP) on long-term heavy-load exercising mice. Peripheral white blood cells (WBC), the absolute value of neutrophils (NEUT), the phagocytic function of macrophages, serum agglutination valence, and the number of plaque-forming cells (PFC) were evaluated 4 weeks after gavaging long-term heavy-load exercising mice with GLP. After exercise, the WBC count in peripheral blood, absolute neutrophil count, macrophage phagocytic index, serum agglutination valence, and the number of plaque-forming cells were significantly reduced in the mice not fed GLP. Both medium and high doses of GLP drastically increased peripheral WBC, absolute neutrophil count, macrophage phagocytic index, serum agglutination valence, and the number of plaque-forming cells in long-term heavy-load exercising mice. High doses of GLP increased peritoneal macrophage phagocytic rate considerably. With this study, we demonstrate that 4 weeks of heavy-load exercise can lead to exercise-induced immunosuppression in mice. A supplement of GLP fed to these mice improves both non-specific and specific immune responses among these mice. The effect for the high-dose GLP treatment is especially significant.

Ethanol (EtOH)‐Induced TGF‐β1 and Reactive Oxygen Species Production Are Necessary for EtOH‐Induced Alveolar Macrophage Dysfunction and Induction of Alternative Activation

Previous studies have shown that chronic ethanol (EtOH) ingestion results in impaired alveolar macrophage function, increased TGF-β(1) production, and decreased antioxidant availability. Similarly, alternative activation (M2 activation) of alveolar macrophages also induces TGF-β(1) production and impairs macrophage function. However, the potential links between EtOH-induced alveolar macrophage derangements, M2 activation, TGF-β(1) production signaling, and oxidant stress have yet to be examined. We hypothesized that EtOH-induced oxidant stress and induction of TGF-β(1) signaling result in alternative activation which subsequently impairs the phagocytic capacity of alveolar macrophages. Primary rat alveolar macrophages and the alveolar macrophages cell line NR8383 were treated with 0.08% EtOH±the antioxidant glutathione (GSH) or a TGF-β(1) neutralizing antibody for 5days. Outcome measures included TGF-β(1) production, reactive oxygen species (ROS) production, phagocytic capacity, and expression of markers of M2 activation. Chronic EtOH treatment greatly decreased alveolar macrophage phagocytic function, increased ROS production, increased TGF-β(1) , and increased expression of markers of M2 activation. GSH supplementation and inhibition of TGF-β(1) signaling during EtOH treatment prevented these alterations. EtOH treatment increased oxidant stress, TGF-β(1) production, and alternative activation in NR8383 cells. However, GSH supplementation and ablation of TGF-β(1) signaling prevented these effects. This suggested that the EtOH-induced switch to an M2 phenotype was a result of decreased antioxidant availability and increased TGF-β(1) signaling. Preventing EtOH-induced induction of alternative activation may improve alveolar macrophage function in alcoholic subjects and decrease the risk of respiratory infections.

Polysaccharide Extracted from Rheum Tanguticum Prevents Irradiation-induced Immune Damage in Mice

To investigate the protective effect of purified fraction 1 polysaccharide extracted from Rheum tanguticum RTP1 on irradiation-induced immune damage in mice. Kunming mice were randomly divided into five groups: normal group (NC), irradiation control group (IC), RTP1 low dose (200 mg/kg), middle dose (400 mg/kg) and high dose (800 mg/kg) groups. RTP1 was administered by the gastric route for 14 d, mice in the NC and IC groups being given by 0.9% sodium chloride solution in the same way. The mice in all groups except NC group were irradiated with 2.0 Gy⁶⁰Co γ-ray on the fourteenth day. Immune indives of non-specific immune function, cellular immunity and humoral immunity were assessed at the 24th hour after radiation. Compared with the IC group, the spleen index, thymus index, rate of carbon clearance, phagocytic function of macrophages, lymphocyte proliferation, hemolysin value of blood serum and NK activity were increased markedly (P < 0.05 or P < 0.05). RTP1 has an obvious protective effects on damage in γ-ray radiated mice.

A Non-invasive Technique to Measure Lipopolysaccharide (LPS)-Stimulated Macrophage Phagocytic Function

Introduction: Sepsis is the leading cause of death in critically ill patients in the United States. Clinical diagnosis of sepsis relies heavily on bacterial cultures and the manifestation of clinical signs. However, underlying biological changes of sepsis may occur hours to days before the clinical presentation of symptoms, therefore early detection of biological perturbations may provide crucial opportunities for early diagnosis and treatment of sepsis. Macrophages play a pivotal role in the early systemic response to infection by phagocytosis of microbes and augmentation of the host immune response, in liver and elsewhere.

Experiments on Antitumor Activity and Immunological Mechanisms of Scutellaria Barbata Polysaccharides

Abstract This research aimed at studying the antitumor activity and immunological mechanisms of Scutellaria barbata polysaccharides (SBPS). Hepatocarcinoma H22-bearing mice were randomly divided into negative control group, SPS group, and polyporus polysaccharide group. After the drug administration for 10 consecutive days, the inhibitory rate of tumors, thymus index, and spleen index, and the phagocytic function of macrophages were observed. ELISA method was used in the determination of the serum level of IL-2. The comparison was made among the groups. The results showed that SPS can effectively inhibit the growth of HepA. The inhibitory rate of tumors was 34.35%. The weight of immune organs was also increased among HepA-bearing mice. The serum level of IL-2 and the phagocytic function of macrophages were also increased. Thus, it can be concluded that SPS has obvious antitumor activity. The mechanism is due to the enhancement of the immune function.

Influence of joint exposure to diazinon, propoxur and bisphenol A on phagocytosis of RAW264.7 cell

To explore the toxicity of joint exposure to diazinon, propoxur and bisphenol A on phagocytosis. Flow cytometer was employed to detect the influence of diazinon and bisphenol A, propoxur and bisphenol A in mixture (mixed according to ratio of IC(50)) on mouse macrophage RAW264.7 cells' function to phagocyte fluorescent microspheres, adopting the percentage of phagocytic cells (PP) and the phagocytic index (PI) as measurement indicators. The final concentrations of mixture of diazinon and bisphenol A were (0.4 + 0.1), (3.6 + 0.7), (36.2 + 7.2), (43.4 + 8.7), (52.1 + 10.4), (62.5 + 12.5), (75.0 + 15.0) µg/ml; while those of mixture of propoxur and bisphenol A were (0.2 + 2.0 × 10(-2)), (2.4 + 0.2), (23.7 + 2.0), (35.6 + 3.0), (53.3 + 4.4), (80.0 + 6.7), (120.0 + 10.0) µg/ml. Then based on the dose-response relationship, a 2 × 2 factorial design was then carried out among different doses of mixture with statistical significance to statistically evaluate the interaction between diazinon and bisphenol A, propoxur and bisphenol A. After the joint exposure, compared to the control group (PP = (23.6 ± 2.2)%; PI = 0.36 ± 0.03), any dose of the mixture of diazinon and bisphenol A ((52.1 + 10.4), (62.5 + 12.5), (75.0 + 15.0) µg/ml) could significantly increase the levels of PP ((29.0 ± 1.4)%, t = 3.89, P < 0.05; (30.2 ± 2.3)%, t = 4.74, P < 0.05; (35.0 ± 3.4)%, t = 8.21, P < 0.05) and PI (0.43 ± 0.03, t = 3.86, P < 0.05; 0.41 ± 0.02, t = 2.95, P < 0.05; 0.46 ± 0.03, t = 5.34, P < 0.05); while that of propoxur and bisphenol A ((35.6 + 3.0), (53.3 + 4.4), (80.0 + 6.7), (120.0 + 10.0) µg/ml) reduced the levels of PP ((20.6 ± 1.1)%, t = -3.00, P < 0.05; (20.2 ± 1.0)%, t = -3.42, P < 0.05; (19.4 ± 1.3)%, t = -4.23, P < 0.05; (18.8 ± 2.1)%, t = -4.81, P < 0.05) and PI (0.31 ± 0.01, t = -4.75, P < 0.05; 0.31 ± 0.01, t = -4.58, P < 0.05; 0.30 ± 0.01, t = -4.92, P < 0.05; 0.27 ± 0.02, t = -7.80, P < 0.05) on the contrary. The 2 × 2 factorial design was carried out between the mixture of diazinon (60.0 µg/ml; PP = (28.5 ± 3.4)%; PI = 0.49 ± 0.07) and bisphenol A (12.0 µg/ml; PP = (35.7 ± 2.7)%; PI = 0.67 ± 0.07), and the mixture of propoxur (48.0 µg/ml ; PP = (28.1 ± 2.2)%; PI = 0.48 ± 0.04) and bisphenol A (4.0 µg/ml; PP = (34.4 ± 2.7)%; PI = 0.59 ± 0.07). The mixture of diazinon and bisphenol A (PP = (30.4 ± 1.4)%, F(interaction) = 6.22, P < 0.05; PI = 0.53 ± 0.03, F(interaction) = 7.35, P < 0.05) and the mixture of propoxur and bisphenol A (PP = (27.5 ± 4.1)%, F(interaction) = 4.56, P < 0.05; PI = 0.46 ± 0.08, F(interaction) = 11.13, P < 0.05) both showed a significant antagonistic interaction on phagocytosis of RAW264.7 cell. It is suggested that the interactions between diazinon & bisphenol A and propoxur & bisphenol A both played the antagonistic role on phagocytic function of macrophages in vitro.