摘要:

AbstractThe present study demonstrates that with time in culture blood monocytes (MO) lose their ability to express procoagulant activity (PCA) and secrete tumor necrosis factor‐alpha (TNFα) in culture medium in response to lipopolysaccharide (LPS) stimulation. Thus, upon 10 μg/ml LPS stimulation for 4 hours 2‐day‐old MO produced lower levels of PCA and TNFα than fresh MO. The decrease in responsiveness was not caused by cell death, since in the case of TNFα it was fully reversible by interferon‐gamma (IFN‐γ). Compared with cells pre‐incubated in medium alone, the responsiveness of MO pre‐incubated in LPS was further decreased. Thus, in MO LPS pre‐incubation was followed by an LPS refractory state. It was expected that the decrease in responsiveness induced by cultivation in medium alone was mediated by LPS contamination of culture medium. However, as we were unable to prevent this decrease by neutralizing LPS contamination of the culture medium with polymyxin B, the loss in LPS‐induced activities of cultured MO is likely to be mediated by culture conditions other than LPS contamination. Taken together the present data demonstrate that LPS‐dependent as well as LPS‐independent pathways of MO desensitization to LPS exist.

ISSN:0741-5400    

DOI:10.1002/jlb.50.3.215

出版商:Wiley    

年代:1991

数据来源: WILEY

摘要:

AbstractIn this report we show that phagocytosis of yeast particles opsonized with IgG (Y‐IgG) by human polymorphonuclear cells (PMN) results in the selective induction of tumor necrosis factor (TNF‐α) messenger RNA (mRNA) and release of its mature protein. Lipopolysaccharide (LPS) was also found able to induce TNF‐α secretion by PMN, but was a less potent stimulus compared with Y‐lgG. There was no evidence of interleukin‐6 (IL‐6) gene expression in PMN after phagocytosis of Y‐lgG or in response to LPS, whereas IL‐6 mRNA expression and secretion were induced by either stimulus in monocytes. These findings demonstrate that a physiological function such as phagocytosis modulates the gene expression for a cytokine in PMN and shed new light on the understanding of the pathogenesis of the inflammatory process.

ISSN:0741-5400    

DOI:10.1002/jlb.50.3.223

出版商:Wiley    

年代:1991

数据来源: WILEY

摘要:

AbstractThe time course of phagocytosis and phagosome‐lysosome fusion (PLF) in lung and peritoneal macrophages (LMs and PMs) was measured. Lysosomes in unelicited hamster LMs and PMs were labeled with lucifer yellow. Macrophages then phagocytized heat‐killedSaccharomyces cerevisiae(yeast) and were evaluated at several time points for the degree to which yeast particles were adherent vs. internalized and for the presence or absence of PLF as based on the presence or absence of lucifer yellow in yeast‐containing phagosomes. A three‐compartment model (adherent, ingested, fused) of independent phagocytosis and PLF was developed; the number of yeast particles in each compartment was counted, and rate constants for ingestion and fusion were determined. Comparison of rate constants showed that ingestion was significantly faster in PMs (0.047 ± 0.005 min‐1) than in LMs (0.016 ± 0.005 min‐1) (mean ± pooled SEM;P<0.001). Similarly, PLF was significantly faster in PMs (0.109 ± 0.013 min‐1) than in LMs (0.046 ± 0.013 min‐1) (P<0.003).

ISSN:0741-5400    

DOI:10.1002/jlb.50.3.229

出版商:Wiley    

年代:1991

数据来源: WILEY

摘要:

AbstractThe motile and rheologic properties of hamster lung and peritoneal macrophages (LMs and PMs) were examined by following the motions of magnetizable iron oxide (γ‐Fe2O3) particles contained within phagolysosomes of these cells. As a measure of intracellular motility, γ‐Fe2O3particles in cells were magnetically aligned and the decay rate of the remanent magnetic field (RMF) in the direction of initial magnetization was monitored over time. Cytoplasmic rheology was measured by twisting the intracellular particles with a magnetic field (Btw) applied perpendicularly to the direction of initial magnetization. We measured changes in the RMF associated with application and removal of Btw. Intracellular motility in LMs and PMs was not significantly different (P>0.20); similarly, cytoplasmic viscosity was not significantly different in LMs and PMs (P>0.12); deformation on application of torque was significantly greater (P<0.0001) and elastic recoil on removal of torque was significantly smaller (P<0.0001) in PMs than in LMs; and by qualitative observation, the yield stress of cytoplasm (associated with a plastic, nonrecoverable deformation) was lower in PMs than in LMs. These results show that although cytoplasmic motion and viscosity are similar in the two cell types, PM cytoplasm is less stiff than LM cytoplasm as determined by yield stress.

ISSN:0741-5400    

DOI:10.1002/jlb.50.3.240

出版商:Wiley    

年代:1991

数据来源: WILEY

摘要:

AbstractThe concentration and distribution of F4‐80 positive cells (macrophages) and common leukocyte antigen (CLA) positive (bone marrow derived) cells were assessed in mouse uterus between days 1 and 8 of pregnancy. High numbers of polymorphonuclear leukocytes and lymphocytes were present on days 1 and 2, but not thereafter. Granulocytes were found both in the endometrium and within the luminal epithelium. The percentage of total cells contributed by macrophages was high on days 1 and 2. That percentage decreased significantly on day 3, then increased again on day 5 and remained high through day 8. Macrophages always were found in myometrial stroma. Macrophages were found throughout the endometrium on days 2 through 8. High numbers of macrophages were observed near epithelia, particularly on days 1,2,4, and 5. Few F4‐80+or CLA+cells were observed within the developing primary and secondary decidua. The results demonstrate that an inflammation‐like cellular response occurs in the uterus following mating and that macrophages are a major cellular component of the uterus during early pregnancy.

ISSN:0741-5400    

DOI:10.1002/jlb.50.3.252

出版商:Wiley    

年代:1991

数据来源: WILEY

摘要:

AbstractCongenic strains of mice susceptible (B10A.Begs) or resistant (B10A.Bcgr) to BCG were established. Here we describe the model system which has been established to analyze the functional activities of macrophages in the two strains. We have immortalized bone marrow macrophages from B10A.Bcgsand B10A.Bcgrcongenic strains of mice and derived cloned macrophage lines designated B10S and B10R, respectively. B10R and B10S cell lines exhibited surface markers and morphology typical of macrophages. B10S and B10R were similar in their phagocytic activity, in their level of c‐fms, in their transforming growth factor β (TGFβ) mRNAs expression, and in their expression of tumoricidal activity in response to interferon‐gamma (IFNγ) plus lipopolysaccharides (LPS). However, B10R macrophages expressed a higher level of la mRNA when activated with IFNγ compared with B10S macrophages. Analysis of the bacteriostatic activity of the two cell lines revealed that B10R macrophages were much more active in inhibitingMycobacterium smegmatisreplication than B10S. To measure the intracellular destruction of bacilli, a bactericidal assay based on hybridization with an oligonucleotide probe specific for mycobacterial ribosomal RNA was designed. The results demonstrated that B10R macrophages were endowed with enhanced constitutive bactericidal activity as compared with B10S.In conclusion we have obtained macrophage lines from bone marrow of B10A.Bcgsand B10A.Bcgrmice that express to a similar extent functional and phenotypic characteristics of macrophages. However, we demonstrate that relative to B10S macrophages, the B10R macrophages have higher expression of la mRNA and that they are constitutively more active in expressing mycobactericidal activity.

ISSN:0741-5400    

DOI:10.1002/jlb.50.3.263

出版商:Wiley    

年代:1991

数据来源: WILEY

摘要:

AbstractIn the present study we performed experiments to reveal the role off 5‐lipoxygenase products of arachidonic acid in cell‐to‐cell interaction between rat peritoneal macrophages and spleen natural killer (NK) cells. Peritoneal macrophages were found to significantly enhance NK cell activity. It was found that the enhancing activity of macrophages was significantly inhibited by the ingestion of highly purified eicosapentaenoic acid‐ethyl ester (EPA‐E). But direct cytotoxic action of macrophage on target cells (YAC‐1) was unchanged by the ingestion of EPA‐E. In addition, the depressed enhancing activity of EPA‐enriched macrophages (EPA macrophages) was partially, but significantly, restored by the addition of either 10‐10M leukotriene B4(LTB4) or 10‐12M 5‐hydroperoxyeicosatetraenoic acid (5‐HPETE). The partial restoring effect of 10‐10M LTB4was further significantly enhanced by the addition of 5‐HPETE. In contrast 5‐hydroxyeicosatetraenoic acid (5‐HETE) had no modulatory effect on the depressed activity of EPA macrophages. LTB4,5‐HPETE, and 5‐HETE had no direct effect on NK cell activity itself. Significantly less amounts of LTB4and 5‐HETE were produced in EPA macrophages as compared with that in control macrophages. The present study indicates that macrophage modulatory action on NK cells can be partly mediated by LTB4and 5‐HPETE, which are produced in macrophages.

ISSN:0741-5400    

DOI:10.1002/jlb.50.3.273

出版商:Wiley    

年代:1991

数据来源: WILEY

摘要:

AbstractThe stimulatory effects of neutrophil‐activating peptide 1 (NAP‐1), also termed interleukin 8 (IL‐8), neutrophil‐activating peptide 2 (NAP‐2), and melanoma growth‐stimulatory activity (gro/MGSA) on human neutrophils and monocytes were compared on the basis of two responses that can be assessed in real time, the changes in cytosolic free calcium and the respiratory burst. All three peptides induced a rapid and transient rise of cytosolic‐free calcium and the respiratory burst in neutrophils. Both responses were also obtained in monocytes on stimulation with NAP‐1/IL‐8 andgro/MGSA, but not with NAP‐2, which appeared to be more selective for neutrophils. Pretreatment with concanavalin A (ConA) enhanced several fold the rate and duration of the respiratory burst of neutrophils stimulated with all three peptides and of monocytes stimulated with NAP‐1/IL‐8 andgro/MGSA, but not with NAP‐2. Sequential stimulation showed mutual cross desensitization by NAP‐2 andgro/MGSA in neutrophils. In addition, desensitization of neutrophils toward NAP‐2 andgro/MGSA, and of monocytes towardgro/MGSA, was obtained by prestimulation with NAP‐1/IL‐8. Prestimulation with either NAP‐2 orgro/MGSA, however, did not desensitize the cells for NAP‐1/IL‐8.These results suggest that under conditions where multiple stimulatory agents are produced, neutrophil‐activating peptides may contribute to the formation of substantial amounts of oxygen‐derived radicals. In addition, the study shows that NAP‐1/IL‐8 andgro/MGSA, but not NAP‐2, have some stimulatory effects on monocytes as well.

ISSN:0741-5400    

DOI:10.1002/jlb.50.3.279

出版商:Wiley    

年代:1991

数据来源: WILEY

摘要:

AbstractThe accumulation of polymorphonuclear cells (PMN) in tissue is an essential element of the inflammatory response that is important in host defense. Adherence to endothelium constitutes the first step in PMN migration from the vascular compartment to the interstitium. We demonstrate that human peripheral blood mononuclear cells (PBMC) adherent to plastic can result in expression of interleukin‐8 (IL‐8), a potent PMN chemoattractant and activating cytokine. Northern blot analyses showed PBMC adherent to plastic expressed IL‐8 steady‐state mRNA levels by 30 min, peaked at 8 h, and then decreased over the next 16 h. In contrast, nonadherent PBMC (cultured in teflon chambers) expressed less than 25% of the maximal IL‐8 steady‐state mRNA levels as compared with adherent PBMC. Adherent PBMC‐associated IL‐8 determined by immunohistochemistry, supernatant chemotactic bioactivity, and extracellular antigenic IL‐8 paralleled IL‐8 mRNA expression. Antigenic and bioactive IL‐8 were significantly apparent by 4–8 h, respectively, and increased significantly to maximal levels by 24 h. Furthermore, adherent PBMC IL‐8 gene expression was suppressed by either concomitant treatment with actinomycin‐D or cycloheximide, yet specific neutralizing antibodies directed against either IL‐1β or tumor necrosis factor (TNF)‐α failed to alter adherence‐induced steady‐state IL‐8 mRNA levels. These data support the hypothesis that PBMC adherence is an important signal for the production of IL‐8, and may be essential to the development of the inflammatory response through the elicrtation of PMN.

ISSN:0741-5400    

DOI:10.1002/jlb.50.3.287

出版商:Wiley    

年代:1991

数据来源: WILEY

摘要:

AbstractInbred strains of mice, notably the susceptible C57BL/6 and the resistant A/J strains of mice, were infected with a strain ofMycobacterium avium.The infection in the visceral organs of mice was then studied, and the effect of colony‐stimulating factors, i.e., interleukin‐3 (IL‐3), granulocyte‐macrophage colony‐stimulating factor (GM‐CSF), and macrophage colony‐stimulating factor (CSF‐1) on the infectious process was evaluated. Infusion of GM‐CSF, CSF‐1, and IL‐3 led to a significant, albeit rather modest, increase in the mycobacterial resistance of A/J mice, as seen by a decrease in the number of colony‐forming units (CFU) in the organs. Conversely, these CSFs dramatically increased the susceptibility of C57BL/6 mice, as seen by increased bacterial numbers in the spleens and livers. In vitro studies demonstrated that resident peritoneal macrophages from susceptible mice were more permissive than cells from resistant mice for mycobacterial growth. Application of CSFs on peritoneal macrophage monolayers led to an increased growth in both A/J and C57BL/6 monolayers for IL‐3 and CSF‐1 and a small microbiostatic effect for GM‐CSF. Cytokine treatment did not, however, change the resistance/ susceptibility phenotype of isolated macrophages. Our results indicate that CSFs may exert beneficial or detrimental effects on resistance to mycobacteria depending on the host genetic make up.

ISSN:0741-5400    

DOI:10.1002/jlb.50.3.296

出版商:Wiley    

年代:1991

数据来源: WILEY