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1.
The production of H2O2 by blood neutrophils of Syrian hamsters, bearing 10 different transplanted tumors was studied at different stages of tumor growth by the luminol-dependent chemiluminescence (CL) test. It was demonstrated that during the tumors growth, two types of the blood neutrophils CL reaction can be registered. The first type of reaction represents very early and significant decrease of spontaneous CL of blood neutrophils, already evident before the appearance of palpable tumor nodules in animals, bearing in vivo selected cell strains. Subsequent subcutaneous tumor appearance in the animals was followed by increased CL of neutrophils. The second type of reaction was characteristic for in vitro transformed cells never selected in vivo. In this case the increase of CL of blood neutrophils at early stages of tumor growth was followed with the decrease of this activity at the period of active tumor growth. Possible relation of this reactions to the survival and growth of different tumor cells in vivo is discussed.  相似文献   

2.
The luminol-dependent chemiluminescence (CL) activity of peritoneal exudate cells and blood neutrophils of Syrian hamsters inoculated intraperitoneally with heat-inactivated microbial particles of Candida albicans, (C. albicans), heated irradiated normal cells and native or heated irradiated malignant tumor cells was studied. The inoculation with particles of C. albicans and heated normal cells induced significant activation of CL of peritoneal exudate cells, but did not influence the CL reaction of blood neutrophils. The inoculation of animals with nonheated irradiated tumor cells led to increase of CL response of both peritoneal exudate cells and blood neutrophils. The inoculation with heated irradiated tumor cells did not activate CL of peritoneal exudate cells and led to slight, but long-lasting decrease of CL response of blood neutrophils.  相似文献   

3.
Most bacteria that enter the bloodstream are taken up by the liver. Previously, we reported that such organisms are initially bound extracellularly and subsequently killed by immigrating neutrophils, not Kupffer cells as widely presumed in the literature. Rather, the principal functions of Kupffer cells demonstrated herein are to clear bacteria from the peripheral blood and to promote accumulation of bactericidal neutrophils at the principal site of microbial deposition in the liver, i.e., the Kupffer cell surface. In a mouse model of listeriosis, uptake of bacteria by the liver at 10 min postinfection i.v. was reduced from approximately 60% of the inoculum in normal mice to approximately 15% in mice rendered Kupffer cell deficient. Immunocytochemical analysis of liver sections derived from normal animals at 2 h postinfection revealed the massive immigration of neutrophils and their colocalization with Kupffer cells. Photomicrographs of the purified nonparenchymal liver cell population derived from these infected mice demonstrated listeriae inside neutrophils and neutrophils within Kupffer cells. Complementary adhesion molecules promoted the interaction between these two cell populations. Pretreatment of mice with mAbs specific for CD11b/CD18 (type 3 complement receptor) or its counter-receptor, CD54, inhibited the accumulation of neutrophils in the liver and the elimination of listeriae. Complement was not a factor; complement depletion affected neither the clearance of listeriae by Kupffer cells nor the antimicrobial activity expressed by infiltrating neutrophils.  相似文献   

4.
Role of H2-calponin in regulating macrophage motility and phagocytosis   总被引:1,自引:0,他引:1  
The actin cytoskeleton plays a major role in cell motility that is essential for the function of phagocytes. Calponin is an actin-associated regulatory protein. Here we report the finding of significant levels of the h2 isoform of calponin in peripheral blood cells of myeloid lineage. To study the functional significance, h2-calponin gene (Cnn2) interrupted mice were constructed. Germ line transmission of the Cnn2-flox-neo allele was obtained in chimeras from two independent clones of targeted embryonic stem cells. The insertion of the neo(R) cassette into intron 2 of the Cnn2 gene resulted in a significant knockdown of h2-calponin expression. Removing the frt-flanked neo(R) cassette by FLP1 recombinase rescued the knockdown effect. Cre recombinase-induced deletion of the loxP-flanked exon 2 eliminated the expression of h2-calponin protein. H2-calponin-free mice showed reduced numbers of peripheral blood neutrophils and monocytes. H2-calponin-free macrophages demonstrated a higher rate of proliferation and faster migration than that of h2-calponin-positive cells, consistent with a faster diapedesis of peripheral monocytes and neutrophils. H2-calponin-free macrophages showed reduced spreading in adhesion culture together with decreased tropomyosin in the actin cytoskeleton. The lack of h2-calponin also significantly increased macrophage phagocytotic activity, suggesting a novel mechanism to regulate phagocyte functions.  相似文献   

5.
Recently it has been recognized that IL-1 plays an important role in hematopoietic regulation. Administration of 5-fluorouracil (5-FU) to mice causes prolonged neutropenia. rHIL-1 injected to mice after 5-FU, accelerated the recovery of hematopoietic progenitors and blood neutrophils. The combination of rhIL-1 and rhG-CSF reduced the neutropenic period significantly. Sublethal irradiation of mice induced profound neutropenia for 3 weeks which was associated with 80% mortality. Administration of rhIL-1 20 hours prior to or 2 hours post irradiation resulted in a significantly improved survival and rapid recovery of the neutrophil count. IL-1 administered alone or in combination with other colony stimulating factors to spontaneous breast tumor bearing mice following 5-FU therapy resulted in a rapid recovery of neutrophils, improved survival, and markedly reduced the tumor mass. Experiments in primates demonstrated that rhIL-1 administered to 5-FU treated animals shortened the neutropenic period from 30 to 17 days and increased the number of marrow progenitors responsive to other CSFs. Prolonged administration of IL-1 (14 days) to these animals resulted in a delayed neutrophil recovery as compared to animals receiving short courses of IL-1. rhIL-1 administered to primates receiving marrow grafts after lethal irradiation, did not result in rapid hematopoietic recovery. In humans, studies with CD-34 positive marrow cells showed that IL-1 had a radioprotective effect on a committed and early marrow progenitors. These data show the therapeutic potential of IL-1 in the treatment of chemoradiotherapy induced myelosuppression.  相似文献   

6.
In this study we tested the hypothesis that after administration of a single intraperitoneal dose of concanavalin A (Con-A) to mice, the proportion of neutrophils and macrophages in the peritoneal exudate and their phagocytic and candidacidal activities should change with time. The number of neutrophils in the peritoneal exudate was greatly increased 6 h after administration of Con-A, and those cells were able to kill both intracellular and extracellular yeast and germ tube forms of Candida albicans. Addition of catalase to the culture medium reduced the killing of C. albicans, suggesting that the candidacidal activity depended on the myeloperoxidase system. The survival of mice pretreated with Con-A and submitted to an inoculum of C. albicans 6 h afterwards was twice higher than that of controls, which suggests that neutrophils were able to clear the experimental infection. One day after the treatment, the population of neutrophils in the exudate was about 45%, but after 2 days it was reduced to only 5% and the candidacidal activity was also reduced. After 4 days the exudate contained over 95% of macrophages, the candidacidal activity reached a maximum, and the phagocytosis mediated by both complement receptors and mannose receptors was increased. Uptake of FITC-mannose-BSA by macrophages was maximal on about the 4th day and was inhibited by mannan, suggesting that treatment with Con-A increased the activity of mannose receptors. These results support the hypothesis that activation of cellular immunity by Con-A occurred in two phases, one dominated by neutrophils, and the other by macrophages expressing increased activity of mannose receptors.  相似文献   

7.
Tumor cells are surrounded by infiltrating inflammatory cells, such as lymphocytes, neutrophils, macrophages, and mast cells. A body of evidence indicates that mast cells are associated with various types of tumors. Although role of mast cells can be directly related to their granule content, their function in angiogenesis and tumor progression remains obscure. This study aims to understand the role of mast cells in these processes. Tumors were chemically induced in BALB/c mice and tumor progression was divided into Phases I, II and III. Phase I tumors exhibited a large number of mast cells, which increased in phase II and remained unchanged in phase III. The expression of mouse mast cell protease (mMCP)-4, mMCP-5, mMCP-6, mMCP-7, and carboxypeptidase A were analyzed at the 3 stages. Our results show that with the exception of mMCP-4 expression of these mast cell chymase (mMCP-5), tryptases (mMCP-6 and 7), and carboxypeptidase A (mMC-CPA) increased during tumor progression. Chymase and tryptase activity increased at all stages of tumor progression whereas the number of mast cells remained constant from phase II to III. The number of new blood vessels increased significantly in phase I, while in phases II and III an enlargement of existing blood vessels occurred. In vitro, mMCP-6 and 7 are able to induce vessel formation. The present study suggests that mast cells are involved in induction of angiogenesis in the early stages of tumor development and in modulating blood vessel growth in the later stages of tumor progression.  相似文献   

8.
Peripheral blood neutrophils of 123 patients in stage Ia of the endometrial cancer have been assayed. The receptor system and ability of neutrophils to form extracellular traps (NET activity) were assessed by fluorescence microscopy, and spontaneous production of IL-2, IFN-γ, matrix metalloproteinase (MMP), G-CSF was found to exist determined with enzyme-linked immunosorbent assay. Phagocytic and myeloperoxidase activity, the level of cationic proteins, and neutrophil activity were evaluated in an NBT test determining the oxygen-dependent bactericidal action of neutrophils. Topology and rigidity of neutrophil membranes were assessed using scanning probe microscopy. It was established that an increased number of neutrophils was accompanied by changes of their receptor system, aerobic and anaerobic cytotoxicity, enhanced phagocytic activity, and reduced NET activity. The secretory activity of neutrophils changed. An increased level of MMP-1, possibly by enhanced production of reactive oxygen species, reduced IL-2 level, and a drastic increase in G-CSF were observed. The architectonics of neutrophils at stage Ia of endometrial cancer was characterized by altered cell shape and granularity loss. The rigidity of the cell membrane decreased. The changes in neutrophil morphology and persistent hyperactivity suggest the existence of the equilibrium between the immune system and the tumor in stage Ia of endometrial cancer.  相似文献   

9.
The influence of the products secreted by activated neutrophils (neutrophilokins) of mice, both intact and infected with staphylococci, on the activity of mouse spleen cells in the graft-versus-host reaction, immune response to sheep red blood cells and the antigen-presenting function of peritoneal macrophages was studied. Neutrophilokins of intact mice stimulated the activity of immunocompetent cells. Neutrophilokins obtained from infected mice on day 3 after infection produced an immunosuppressing effect. On day 7 after infection the immunostimulating activity of neutrophils was restored and showed practically no difference from the normal level.  相似文献   

10.
Miao JF  Zhu YM  Gu BB  Wang XB  Zou SX  Deng YE 《Cytokine》2007,40(2):135-143
The aim of this study was to evaluate in rats, changes in peripheral blood immune cells and mammary tissue after an intramammary infusion of lipopolysaccharide (LPS). The results of the study showed that infusion of LPS induced a rapid migration of neutrophils (PMNs) from the blood to mammary alveoli, increased the activity of myeloperoxidase (MPO) and the concentration of tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), and interleukin-6 (IL-6) in mammary tissues, decreased the activity of myeloperoxidase in serum and reduced the CD4+/CD8+ ratio. This is the first report of changes in peripheral blood immune cells and mammary tissue in rat mastitis.  相似文献   

11.
Polymorphonuclear granulocytes (neutrophils) release the reactive oxygen species (ROS) for destruction of pathogens, providing quicker of an organism from infections and own defective of transformed cells. Reactive oxygen species are also potential carcinogens because they facilitate mutagenesis, tumor promotion and progression. Balance between these opposite influences is supported by coordinated interrelations in intracellular signaling systems. Tumor growth influence on the NADPH oxidase in peripheral innate immune cells is unclear. A solid cancer model was developed after an intramuscular injection of Ehrlich carcinoma cells into hind leg of NMRI strain mice. Intensity of the respiratory burst was estimated by luminol-dependent chemiluminescence technique. Transformation of inflammatory reaction was revealed during tumor growth: greater amounts of neutrophils were recruited into peritoneal cavity; sizes of the cells, their nuclei and granules were enlarged; the ratio of different cell types in peritoneal exudation was changed. The study revealed that tumor progression was accompanied by significant changes in functional activity of neutrophils. Dynamic increase in spontaneous level of ROS production and concentration-dependent change of intensity of the respiratory burst induced with chemotactic peptide N-formyl-Met-Leu-Phe (fMLF) was revealed in peripheral neutrophils under tumor growth conditions. It was found that effects of inhibitors of tyrosine protein kinases, protein kinase C, mitogen-activated protein kinase p38MAPK (p38MAPK) and phosphatidylinositol 3-kinase (PI3K) were altered in neutrophils from tumor-bearing mice in comparison with the cells of control mice. This indicates a change in the role of the enzymes in regulation of the neutrophil respiratory burst. Data obtained show that p38MAPK and PI3K entangle up- and down-regulation of NADPH oxidase in peripheral neutrophils during tumor growth.  相似文献   

12.
Experiments on noninbred white mice have revealed that in the animals infected with S. moscow secondary immunodeficiency develops, which is manifested by a significant decrease in the activity of the bactericidal system of peripheral blood granular leukocytes. Simultaneously, the content of myeloperoxidase in the blood neutrophils of infected mice decreases 1.4 times and the content of lysozyme in these neutrophils decreases 2 times. Such changes are the consequence of an increase in the secretory activity of cells, occurring in the process of the development of Salmonella infection.  相似文献   

13.
The mechanism of tissue injury at the cellular level by following the chemiluminescence response of various phagocytes in E. coli induced experimental pyelonephritis in mice was investigated. There was a marked increase in the capacity of various phagocytic cells viz; renal neutrophils and macrophages peritoneal macrophages, blood monocytes and neutrophils to produce reactive oxygens species through the respiratory burst activity as monitored by the chemiluminescence response. The chemiluminescence response was observed to be increased significantly (p less than 0.001) with increasing days post infection in all phagocytic cells. However, the quantity of total reactive oxygen species produced per million cells was much more in the renal and peritoneal macrophages as compared to blood monocytes and neutrophils. The peak chemiluminescence response time was observed to be decreased from 4 to 2 minutes with the progression of the diseases. The implications of these findings have been discussed.  相似文献   

14.
Chemokines are critical for the recruitment of effector immune cells to sites of infection. Mice lacking the chemokine receptor CCR1 have defects in neutrophil trafficking and proliferation. In the present study, we tested the susceptibility of CCR1 knockout mice to infection with the obligate intracellular protozoan parasite Toxoplasma gondii. In comparison with parental wild-type mice, CCR1(-/-) mice exhibited dramatically increased mortality to T. gondii in association with an increased tissue parasite load. No differences were observed in Ag-specific T cell proliferation or in cytokine responses between mutant and wild-type mice. However, the influx of PMNs to the peripheral blood and to the liver were reduced in CCR1(-/-) mice during early infection. Our results suggest that CCR1-dependent migration of neutrophils to the blood and tissues may have a significant impact in controlling parasite replication.  相似文献   

15.
The heterotransplantability of HOTHC line (human anaplastic thyroid carcinoma) into the subcutis of BALB/c nude mice and the biological properties of grafts were discussed. (1) The HOTHC line showed high transplantability, and 1 x 10(4) cells produced anaplastic carcinoma (giant cell type) containing the colloid-like substance. (2) The grafted tumors grew rapidly and the mice were dead within 2 months after transplantation. (3) The number of leukocytes (neutrophils) of mouse peripheral blood increased as the tumor size increased, and the leukocyte count returned to a normal value after removal of the tumor. (4) The conditioned media of HOTHC line formed colonies of granulocytes (neutrophils) on soft agar. These phenomena revealed that HOTHC is a granulocyte-colony stimulating factor-producing line. (5) The conditioned media of HOTHC line showed promoting-effect on neovascularization on the chorioallantoic membrane.  相似文献   

16.
CD95 (APO-/Fas) ligand (CD95L) is a member of the TNF family predominantly expressed by activated T and NK cells but also by tumors of diverse cellular origin. CD95L trimerizes surface CD95 expressed by target cells that subsequently undergo apoptosis. The role of the CD95/CD95L system in the down-regulation of an immune response (activation-induced cell death) is established. However, it is so far unclear why tumors express CD95L. To investigate whether tumors use the CD95L to down-regulate an anti-tumor immune response, we established a transgenic (tg) mouse model consisting of 1) apoptosis-resistant tumor cells, designated LKC-CD95L, which express functional CD95L and the model tumor Ag K(b); and 2) perforin knockout (PKO) anti-K(b) TCR tg mice. L1210-Fas antisense expressing K(b), crmA, and CD95L (LKC-CD95L) killed CD95(+) unrelated tumor targets and Con A-activated splenocytes from anti-K(b) TCR tg PKO mice by a CD95L-dependent mechanism in vitro. However, we could not detect any cytotoxic activity against anti-tumor (anti-K(b)) T cells in vivo. We also observed reduced growth of LKC-CD95L in nude mice and rapid rejection in anti-K(b) TCR tg PKO mice. Because the tumor cells are resistant to CD95L-, TNF-alpha-, and TNF-related apoptosis-inducing ligand-induced apoptosis and the mice used are perforin-deficient, the involvement of these four cytotoxicity mechanisms in tumor rejection can be excluded. The histological examination of tumors grown in nude mice showed infiltration of LKC-CD95L tumors by neutrophils, whereas L1210-Fas antisense expressing K(b) and crmA (LKC) tumor tissue was neutrophil-free. Chemotaxis experiments revealed that CD95L has no direct neutrophil-attractive activity. Therefore, we conclude that LKC-CD95L cells used an indirect mechanism to attract neutrophils that may cause tumor rejection.  相似文献   

17.
Neutrophils are the first infiltrating cell population to appear within the CNS during infection with the neurotropic JHM strain of mouse hepatitis virus (JHMV). To determine whether neutrophils play a role in limiting acute JHMV infection, mice were depleted of neutrophils. Infection of neutropenic animals resulted in increased levels of virus replication and mortality compared with control mice. Furthermore, neutropenia resulted in significantly reduced mononuclear leukocyte infiltration possibly due to reduced loss of blood brain barrier integrity during acute JHMV infection. These data suggest that infiltrating neutrophils are crucial for limiting virus replication during acute JHMV infection, contribute to the loss of blood brain barrier integrity and play a role in shaping adaptive immunity within the CNS.  相似文献   

18.
To address how FasL-expressing tumors induce neutrophil emigration and abrogate tumorigenicity, we investigated the behavior of FasLcDNA-transfected hepatoma MH134 (G2) cells injected into wild-type (+) mice, lpr(cg)/lpr(cg) (lpr(cg)) mice with death domain (DD)-mutated Fas, and gld/gld lpr/lpr (gld/lpr) mice with defects in FasL/Fas. G2 cells were eradicated after extensive infiltration of neutrophils around them in + mice but formed tumors without such infiltration in lpr(cg) and gld/lpr mice. Abundant cell debris suggestive of apoptosis of infiltrating neutrophils was found among G2 tumor cells in + mice but a few neutrophils infiltrating among G2 cells were intact in lpr(cg) and gld/lpr mice. Collectively, these results indicate the crucial role of Fas DD in Fas-mediated apoptosis of neutrophils and suggest that apoptosis of neutrophils with FasL-expressing tumors may trigger the extensive infiltration of neutrophils, resulting in violent inflammation and ultimately in the eradication of tumor cells.  相似文献   

19.
Relative contribution of LFA-1 and Mac-1 to neutrophil adhesion and migration.   总被引:29,自引:0,他引:29  
To differentiate the unique and overlapping functions of LFA-1 and Mac-1, LFA-1-deficient mice were developed by targeted homologous recombination in embryonic stem cells, and neutrophil function was compared in vitro and in vivo with Mac-1-deficient, CD18-deficient, and wild-type mice. LFA-1-deficient mice exhibit leukocytosis but do not develop spontaneous infections, in contrast to CD18-deficient mice. After zymosan-activated serum stimulation, LFA-1-deficient neutrophils demonstrated activation, evidenced by up-regulation of surface Mac-1, but did not show increased adhesion to purified ICAM-1 or endothelial cells, similar to CD18-deficient neutrophils. Adhesion of Mac-1-deficient neutrophils significantly increased with stimulation, although adhesion was lower than for wild-type neutrophils. Evaluation of the strength of adhesion through LFA-1, Mac-1, and CD18 indicated a marked reduction in firm attachment, with increasing shear stress in LFA-1-deficient neutrophils, similar to CD18-deficient neutrophils, and only a modest reduction in Mac-1-deficient neutrophils. Leukocyte influx in a subcutaneous air pouch in response to TNF-alpha was reduced by 67% and 59% in LFA-1- and CD18-deficient mice but increased by 198% in Mac-1-deficient mice. Genetic deficiencies demonstrate that both LFA-1 and Mac-1 contribute to adhesion of neutrophils to endothelial cells and ICAM-1, but adhesion through LFA-1 overshadows the contribution from Mac-1. Neutrophil extravasation in response to TNF-alpha in LFA-1-deficient mice dramatically decreased, whereas neutrophil extravasation in Mac-1-deficient mice markedly increased.  相似文献   

20.
In experiments on mice the authors studied the correlation of the levels of the activity of a number of enzymes (dehydrogenase and acid phosphatase) of lymphocytes and neutrophils at three levels of organization: subcellular--inside the lymphocytes and neutrophils; intercellular--coordination of the enzymatic activity of two types of blood cells; temporary--inter-conjunction of the levels of metabolism in the blood cells prior to and in dynamics after infection. R. P. Nartsissov's cytochemical method with the use of n-nitrotetrazolium was employed. Introduction of systemic conceptions into the cytochemical analysis of neutrophils and lymphocytes made it possible to reveal a peculiarity of the metabolic status of the blood cells involved into the inflammatory process and also to determine coadaptation elements of the two types of leukocytes.  相似文献   

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