摘要:

AbstractThe use of palmitate‐derivatized antibodies (pal‐Ab) for “arming” macrophage (Mφ) effector cells for antibody‐dependent cellular cytotoxicity (ADCC) is described. Pal‐Ab were incorporated onto the Mφ plasma membranes by insertion of the palmitate hydrocarbon chains into the outer leaflet of the phospholipid bilayer. Mφ bearing pal‐Ab specific for chicken erythrocytes (CE) mediated efficient destruction of the CE targets. Neither non‐ADCC effector cell populations nor pal‐Ab consisting of antibody F(ab')2fragments effected significant CE lysis. Mφ bearing pal‐Ab that were not specific for CE did not mediate CE destruction, nor did anti‐CE pal‐Ab‐bearing Mφ lyse nonspecific human erythrocyte targets. In this system of effector cellarming, the palmitate anchor of pal‐Ab allows for the incorporation of large numbers of antibodies onto the effector cell surface, where they can promote efficient target cell capture and engage preexisting or newly expressed FcR on the effector cell surface. The results in this study, together with those from previous and ongoing investigations in which F(ab')2pal‐Ab were shown to mediate Fc receptor (FcR)‐independent cytotoxicity by natural killer (NK) cells and Mφ populations at appropriate states of activation, suggest that pal‐Ab, by directing both ADCC and FcR‐independent effector cell activity onto a specified target, offer important advantages over other methods of effector cellarming.

ISSN:0741-5400    

DOI:10.1002/jlb.49.1.1

出版商:Wiley    

年代:1991

数据来源: WILEY

摘要:

AbstractThe spontaneous tumoricidal abilities of alveolar and peritoneal macrophages from C57B1/6 mice bearing a metastatic or a nonmetastatic cloned variant of Lewis lung carcinoma (LLC) were measured. Cytotoxicity by alveolar macrophages was enhanced during the first few weeks after subcutaneous (s.c.) or intravenous (i.v.) injection of metastatic LLC‐C3 cells, but not after injection of nonmetastatic LLC‐C8 cells. Alveolar macrophages from mice with s.c.‐lnjected metastatic tumors, but not with nonmetastatic tumors, could be further activated in vitro, but not beyond the maximal level of spontaneous cytotoxicity. Late in tumor growth, the spontaneous cytotoxicity by alveolar macrophages of metastatic LLC‐C3 tumor bearers was suppressed and could not be increased by in vitro activation. The tumoricidal abilities of peritoneal macrophages from mice bearing either LLC‐C3 or LLC‐C8 tumors were modulated in a similar way, as were alveolar macrophages. The reduced cytotoxicity by alveolar macrophages from mice with nonmetastatic tumors or from mice bearing large metastatic tumors was not due to suppression by macrophage‐derived prostaglandins. The loss of tumoricidal capabilities by macrophages from mice with large metastatic LLC‐C3 tumors was not caused by elevated systemic prostaglandin E2(PGE2) levels. These results suggest that alveolar and peritoneal macrophages are activated to be cytotoxic during development of pulmonary metastases and do not need to be functionally depressed for successful establishment of metastases.

ISSN:0741-5400    

DOI:10.1002/jlb.49.1.8

出版商:Wiley    

年代:1991

数据来源: WILEY

摘要:

AbstractThere are conflicting data on the effect of bacterial lipopolysaccharides (LPS) on the function of human neutrophils. The present study was designed to examine the relationship between chemical composition and the modulatory effect of LPS on human neutrohpil function. LPS was extracted from five strains ofPseudomonas aeruginosaisolated from cystic fibrosis patients by the hot phenol–water method. Chemical characterization included neutral sugars, amino components, and fatty acids. Neutrophils isolated from peripheral blood of healthy individuals were preincubated with different concentrations of LPS. After preincubation, the chemotaxis and chemiluminescence of neutrophils to various stimuli were determined. It was shown that LPS from different strains did not exert the same degree of regulatory effect on neutrophil functions. LPS from strain 174‐O:9 exerted the most pronounced effect on neutrophil function seen as inhibition of neutrophil chemotaxis toward the chemotactic peptide f‐Met‐Leu‐Phe and zymosan‐activated serum (ZAS) and priming of the cells for ≤8‐fold enhancement of chemiluminescence response to f‐Met‐Leu‐Phe. Conversely, LPS from strain 1118‐O:3 had no effect on neutrophil chemotaxis and a slight effect on chemiluminescence. The major differences in chemical composition of the LPS from these two strains are in the rhamnose and heptose content of the O side chain and in the alanine content of the core region. These data indicate that chemical composition of the LPS molecule may play an important role in biological activity of LPS.

ISSN:0741-5400    

DOI:10.1002/jlb.49.1.15

出版商:Wiley    

年代:1991

数据来源: WILEY

摘要:

AbstractTumor necrosis factor‐α (TNFα) induces surface expression of class II major histocompatibility (MHC) molecules (la molecules) in many cells, including macrophage‐like cell lines. When we tested the effects of this cytokine on murine peritoneal macrophages, TNFα had little effect on surface expression of la. The strong expression of such molecules induced by interferon‐γ (IFN‐γ) was, however, suppressed moderately by TNFα. These effects were reflected at the level of specific messenger RNA (mRNA) as detected by Northern blot analysis. Furthermore, the locus of control appears to be transcriptional; in nuclear run‐on assays, TNFα suppressed the IFNγ‐induced enhancement of transcription for the murine β‐chain of l‐A (l‐Aβ.). Taken together the data suggest that TNFα has little effect on class II MHC genes and surface expression in murine peritoneal macrophages, that TNFα is a modest suppressant of such molecules when their levels are raised by IFNγ, and that these suppressive effects are mediated at the level of transcription.

ISSN:0741-5400    

DOI:10.1002/jlb.49.1.21

出版商:Wiley    

年代:1991

数据来源: WILEY

摘要:

AbstractPrevious studies of human basophil mediator release have noted that the bacterial peptide fmet‐leu‐phe and the anaphylatoxin C5a induce comparable levels of histamine release while only fmet peptide induces leukotriene release. Since 5‐lipoxygenase metabolism of arachidonic acid is calcium dependent, we examined the characteristics of the human basophil [Ca++]iresponse which follows its activation by either fmet peptide or C5a. While the peak [Ca++]iresponse was essentially identical for these two stimuli, fmet peptide induced a prolonged increase in [Ca++]iwhile C5a stimulated only a transient increase in [Ca++]ithat was essentially over within 2 minutes of adding the stimulus. Simultaneous addition of EDTA with fmet peptide revealed the two phases of the [Ca++]iresponse and demonstrated that leukotriene release was dependent on an elevated [Ca++]ilevel in the 2–5 minutes following challenge. Enhancement of leukotriene release induced by C5a by agents such as staurosporine and interieukin‐3 also produced a [Ca++]ikinetic curve which resembled fmet piptide. Single cell studies of the [Ca++]iresponse could detect no subpopulations of cells which responded preferentially to fmet peptide or C5a, eliminating the possibility that the ability of fmet peptide to induce leukotriene was a result of its action on a functionally distinct population of basophils.

ISSN:0741-5400    

DOI:10.1002/jlb.49.1.29

出版商:Wiley    

年代:1991

数据来源: WILEY

摘要:

AbstractThe capacity of alveolar macrophages (AM) obtained from smokers and nonsmokers to secrete cathepsin B and its inhibitor cystatin C was examined because of the concept that an imbalance in the production of proteolytic enzymes and/or their inhibitors could be responsible for the lung damage seen in smokers. Quantitation of immunoprecipitates on Western blots showed that the amount of total cystatin C secreted into the culture medium by AM of smokers was significantly greater than the amount secreted by cells obtained from nonsmokers, whereas the difference between the amount of cathepsin B secreted by the AM of smokers and that from nonsmokers did not appear significant. The cystatin C found in the medium conditioned by AM of nonsmokers appeared to be more heterogeneous in molecular size, presenting either as a single band of about 14 Kd or as a high‐molecular‐weight triplet of about 69 Kd, 63 Kd, and 57.3 Kd. Furthermore, in some cases there were single or doublet bands at 14 Kd as well as the high‐molecular‐weight triplets. In contrast, smokers AM‐conditioned medium uniformly possessed both the low‐and the high‐molecular‐weight cystatin C. Cathepsin B was not detected in Western blots at its reported molecular weights but was identified at the exact area occupied by the higher molecular weight cystatin C, i.e., at bands corresponding to 69 Kd, 63 Kd, and 57.3 Kd. Therefore, it is clear that in culture media of AM, cystatin C and cathepsin B are present as proteinase–antiproteinase complexes. The observation also suggests that in smokers an excess of cystatin C may be elaborated, which, if further substantiated, would show for the first time a likely role for this proteinase inhibitor in vivo.

ISSN:0741-5400    

DOI:10.1002/jlb.49.1.41

出版商:Wiley    

年代:1991

数据来源: WILEY

摘要:

AbstractSJL/J mice are a genetically low‐NK strain, and their cytotoxic activity cannot be augmented with conventional NK inducers. In contrast, effector cells taken from the lymphoid tissues of SJL mice bearing a syngeneic B cell lymphoma (RCS) show variable, but significant levels of cytotoxic activity against NK‐susceptible targets, such as YAC‐1. Previous results suggested that the RCS cells themselves contributed to this cytotoxicity. However, results presented here indicate that most, if not all of the activity present within the lymphoid tissues of RCS‐bearing mice is mediated by RCS‐activated, host NK cells. These results were confirmed by in vitro studies, which demonstrate that both gamma irradiated (γ‐) RCS cells and γ‐allogeneic spleen cells induce cytotoxic activity in SJL spleen cells against YAC targets. However, the cytotoxicity induced by γ‐allogeneic cells is mediated largely by lymphokine‐activated killer (LAK) cells, since these effectors also lyse NK‐resistant target cells, such as L1210. In contrast, the cytotoxic effector cells that are induced by syngeneic γ‐RCS cells cause lysis of YAC targets, but not L1210 target cells. These data indicate that the syngeneic B cell lymphomas of SJL mice are a unique stimulus for host NK cells in this strain. Since activated NK cells produce a variety of lymphokines, RCS stimulation of host NK cells in SJL mice may provide some of the growth‐promoting lymphokines that are known to be necessary for progressive growth of these lymphoma cells.

ISSN:0741-5400    

DOI:10.1002/jlb.49.1.48

出版商:Wiley    

年代:1991

数据来源: WILEY

摘要:

AbstractThe allergic mediator release inhibitor CI‐949 [5‐methoxy‐3‐(1‐methylethoxy)‐1‐phenyl‐N‐1H‐tetwol‐5‐yl‐1H‐indole‐2‐carboxamide, L‐arginine salt] was evaluated for its effects on human neutrophil functions. CI‐949 (100 μM) inhibited spontaneous migration and chemotaxis toward f‐met‐leu‐phe (FMLP) by 49.1% and 45.8%, respectively. At the same concentration, CI‐949 inhibited the phagocytosis of serum‐opsonized zymosan (SOZ) by 39.0%. CI‐949 inhibited leukotriene B4and thromboxane B2release in response to SOZ with IC50S of 2.0 μM and 3.3 μM, while inhibiting the response to FMLP with IC50s of 1.7 and 2.0 μM. CI‐949 also inhibited myeloperoxidase release from primary lysosomal granules in response to the following stimuli with the respective IC50s (μM): C5a (40.3); FMLP (34.4): SOZ (21.4); concanavalin A (Con A) (3.9); and calcium ionophore A23187 (91.2). In contrast, CI‐949 inhibited lysozyme release from secondary granules in response to SOZ and Con A with IC50S of 99.3 and 56.1 μM, while inhibiting the response to C5a, FMLP, and A23187 by 41.2%, 52.4%, and 10.0%, respectively, at 100 μM. CI‐949 (100 μM) had no inhibitory effect against lysozyme release in response to L‐α‐1,2 dioctanoylglycerol (DiC8), or phorbol 12‐myristate 13‐acetate (PMA). CI‐949 inhibited superoxide anion generation stimulated by FMLP and Con A with IC50S of 33.9 and 25.8 μM, while inhibiting the response to C5a, SOZ, and A23187 by 36.6%, 24.8%, and 14.1% and having no effect on the response to DIC8or PMA at 100 μM. These results demonstrate preferential inhibition of arachidonic acid metabolism and degranulation of primary lysosomal granules by CI‐949 with selectivity for stimuli which promote intracellular calcium mobilization or calcium influx.

ISSN:0741-5400    

DOI:10.1002/jlb.49.1.58

出版商:Wiley    

年代:1991

数据来源: WILEY

摘要:

AbstractThe ability of soluble factors to modulate the growth of a virulent strain ofMycobacterium aviumin murine peritoneal macrophages was studied. The virulent strain, TMC 702, grew progressively in the organs of susceptible BALB/C mice. In addition, this strain ofM. aviumgrew progressively in untreated peritoneal macrophages. Treatment of macrophage monolayers with interferon‐gamma (IFN‐γ) did not change significantly the intracellular growth ofM. avium.Addition of indomethacin to IFN‐γ‐treated macrophage monolayers rendered them significantly more bacteriostatic than macrophages treated with interferon alone, suggesting a role for prostaglandins in inducing unresponsiveness to IFN‐γ in infected cells. Additionally, treatment with tumour necrosis factor‐alpha led to a modest increase in bacteriostasis, as compared to untreated monolayers. Further experiments with recombinant interleukins showed that interleukin‐4 (IL‐4), on its own, could increase bacteriostatic activity againstM.aviumin a reproducible fashion. Experiments with interleukin combinations showed that IFN‐γ and IL‐4 treatment of macrophages rendered these cells almost fully bacteriostatic againstM.avium.Inclusion of scavengers of reactive oxygen species did not modify the beneficial effect of IFN‐γ and IL‐4. Overall, our results suggest an important role for interleukins in modulating the interaction between virulent mycobacteria and murine macrophages.

ISSN:0741-5400    

DOI:10.1002/jlb.49.1.65

出版商:Wiley    

年代:1991

数据来源: WILEY

摘要:

AbstractThe experiments described in this report were aimed at determining whether L‐arginine (L‐arg)‐derived nitrogen oxidation products (nitric oxide, nitrous acid, nitrites) are involved in the intracellular killing ofLeishmaniaparasites by activated murine macrophages in vitro. Peritoneal or bone marrow‐derived macrophages were infected withL. enriettiiorL. major, then activated by exposure to recombinant murine interferon‐gamma or to macrophage activating factor (MAF)‐rich media in the presence of li‐popolysaccharide. Activation of macrophages in regular (i.e., arginine‐containing) culture medium led to complete destruction of the microorganisms within 24 h (L. enriettii)or 48 h (L.major), concomitant with accumulation of nitrites (NO2‐) in the culture fluids. When macrophage activation was carried out in L‐arg‐free medium, however, neither parasite killing nor NO2‐production was obtained. A similar inhibition of macrophage leishmanicidal activity and of NO2‐release was observed using media treated with arginase (which converts L‐arg to urea and ornithine), or supplemented with NG‐monomethyl‐L‐arg or guanidine (which inhibit the conversion of L‐arg to nitrogen oxidation products). In all these situations, an excellent correlation between the levels of NO2‐production by macrophages and intracellular killing ofLeishmaniawas observed, whereas no strict correlation was detectable between leishmanicidal activity and superoxide production. Intracellular parasite killing by activated macrophages could be prevented by addition of iron salts to the incubation fluids. Incubation of free parasites with NaNO2at acid pH (which permits the production of nitrous acid) led to immobilisation, multiplication arrest, and morphological degeneration of the microorganisms. Similarly, exposure of infected cells to NaNO2led to killing of the intracellular parasite without affecting macrophage viability. These experiments strongly suggest that the leishmanicidal effect of activated murine macrophages involves the agency of L‐arg‐derived nitrogen oxidation products.

ISSN:0741-5400    

DOI:10.1002/jlb.49.1.73

出版商:Wiley    

年代:1991

数据来源: WILEY