摘要:

AbstractThe issue of whether or not phagocytizedHistoplasma capsulatumyeasts evade phagosome‐lysosome fusion (P‐LF) has been debated by several investigators. To resolve this problem, yet avoid drawbacks associated with the conventional assays of P‐LF (electron microscopy and the acridine orange assay), we used fluorescein isothiocyanate‐labeled dextran (FITC‐dextran) to monitor P‐LF in the macrophage‐like cell line P388D1.D2. Controls indicated that FITC‐dextran could be used to distinguish between evasion of P‐LF byToxoplasma gondiiand phagolysosome formation following ingestion ofSaccharomyces cerevisiae.Phagosomes containingH. capsulatumclearly fused with FITC‐dextran‐labeled lysosomes at a rate comparable to that observed forS. cerevisiae.This was true for several strains ofH. capsulatumincluding two avirulent strains derived in this laboratory. Varying the dose ofH. capsulatumdid not alter the percentage of phagolysosomes formed. Our results indicate thatH. capsulatumis one of a small number of organisms which is able to survive in phagolysosomes.

ISSN:0741-5400    

DOI:10.1002/jlb.43.6.483

出版商:Wiley    

年代:1988

数据来源: WILEY

摘要:

AbstractHigh numbers of large granular lymphocytes (LGL) accumulate in the livers and peritoneal cavities of mice during the course of viral infection. Accumulation of natural killer (NK) cells at day 3 postinfection (p.i.) was shown to be radiation‐sensitive, implying that proliferation was required for this response. Accumulation occurred in splenectomized mice, indicating that the spleen, known to be an organ for mature NK cell proliferation, was not the major source for liver and peritoneal NK/LGL.Significant percentages (>25%) of the LGL found in the liver and peritoneal cavity following viral infection or interferon induction with poly‐inosinic:pory‐cytidylic acid were defined morphologically as blasts (large cells with prominent nucleoli and intensely basophilic cytoplasms containing azurophilic granules). Most blast LGL at day 3 p.i. were sensitive to administration of anti‐asialo GM1serum in vivo, were Lyt‐2‐, and were enriched in populations that lysed NK cell‐sensitive targets in vitro, indicating that these were NK/LGL. At day 3 p.i., leukocytes from the liver and peritoneal cavity incorporated3H‐thymidine and bound to and killed NK cell‐sensitive targets in single‐cell cytotoxicity assays. These data suggest that NK/LGL undergo at least one round of division in the liver and peritoneal cavity during viral infection.In contrast, blast LGL at day 7 p.i. were resistant to in vivo treatments with anti‐asialo GM1serum, were Lyt‐2+, and were enriched in populations of cells that killed virus‐infected histocompatible targets, indicating that they were cytotoxic T lymphocytes (CTL). These results suggest that both NK/LGL and CTL/LGL are capable of blastogenesis and presumed proliferation at sites of virus infection, providing a means for the in situ augmentation of a host's cell‐mediated antiviral defenses.

ISSN:0741-5400    

DOI:10.1002/jlb.43.6.492

出版商:Wiley    

年代:1988

数据来源: WILEY

摘要:

AbstractThy‐1+dendritic epidermal cells (Tdec) are bone marrow‐derived cells of T‐cell lineage. In order to investigate the function of these cells, two interleukin 2‐dependent Tdec lines (AU4 and AU16) were established from ear skin of C3H/HeN (MTV‐) mice and examined for cytotoxicity against various murine tumor cells. The original phenotype of the Tdec, Thy‐1+, AsGM1+, T3+, Lyt‐1‐, Lyt‐2‐, Lyt‐5+, and L3T4‐, was maintained in the cell lines. The Tdec cell lines (AU4 and AU16) lysed a wide spectrum of tumor cell lines in a 4‐hr51Cr‐release assay. AU16 was more effective in killing a syngeneic UV‐induced skin tumor (UV‐2240) and an allogeneic, natural killer cell‐resistant tumor (EL‐4) than the YAC‐1 cell line, which is highly sensitive to natural killer cells. Neither syngeneic nor allogeneic lymphoblasts were killed by AU16. Cytotoxicity was blocked by fixation of AU16 with paraformaldehyde but not by pretreatment of the cells with puromycin or mitomycin C. The finding that two Thy‐1+cell lines derived independently from murine epidermis have unique cytotoxic activity against murine tumor cells suggests that Tdec could play a role in local immune surveillance against skin cancers.

ISSN:0741-5400    

DOI:10.1002/jlb.43.6.502

出版商:Wiley    

年代:1988

数据来源: WILEY

摘要:

AbstractDifferential expression of antibody dependent cellular cytotoxicity (ADCC) effectors was studied in normal Balb/cCrgl mice and those bearing a chemically induced 7, 12 dimethylbenzanthracene mammary adenocarcinoma. Depletion of macrophages from normal mouse splenocytes by Sephadex G‐10 columns resulted in elimination of ADCC. Further separation of the normal G‐10 nonadherent splenocytes on nylon wool columns did not result in any population with significant cytotoxicity. However, Balb/c mice bearing mammary tumors showed enhanced levels of ADCC which were not eliminated by macrophage removal. Lymphocytes from tumor bearers further separated on nylon wool yielded nonadherent and adherent populations both capable of effecting significant ADCC. Treatment of the nylon nonadherent cells of both normal and tumor bearing mice with anti‐asialo GM1(AGM1) and complement decreased the ADCC responses. The same treatment only marginally affected cytotoxic levels of nylon adherent cells from tumor bearers, indicating that these effectors are primarily of non‐NK lineage. In addition, G‐10 nonadherent, nylon adherent cells from tumor bearers separated on a fluorescence activated cell sorter based on the presence of surface immunoglobulins (slg) revealed that both the slg‐and slg+(98% pure) sorted cells were capable of functioning in ADCC. To determine whether in the tumor mice the 2% of slg‐cells present in the slg+sorted population were the ADCC effectors, mixing experiments were done in which up to 10% of slg‐cells from tumor bearers were added to nylon adherent cells from normal mice. No significant increases in ADCC levels were found over that of normal mice. These experiments indicate that the 2% slg‐cells were not the ADCC effectors nor were they inducing normal B cells to exert this type of cytotoxic reaction in vitro. To further substantiate the B cell lineage of the slg+ADCC effectors, surface immunoglobulins were removed with protease treatment. After a 36 hr incubation, 92% of the cells had regenerated their slg. The results presented in this paper demonstrate that various splenic lymphoreticular populations from tumor bearers possess an enhanced cytolytic activity against antibody coated target cells. Among these is a unique nylon adherent slg+cell that is capable of functioning as an ADCC effector.

ISSN:0741-5400    

DOI:10.1002/jlb.43.6.509

出版商:Wiley    

年代:1988

数据来源: WILEY

摘要:

AbstractPeripheral OKT4‐positive T lymphocytes from patients with hypereosinophilia spontaneously and selectively produced an eosinophil chemotactic factor (ECF) with chemokinetic activity. The molecular weight of the ECF was about 45,000 to 70,000. A possible mechanism of its spontaneous production by T lymphocytes was analyzed. Culture supernatants of blood monocytes from the patients showed little or no ECF activity, but they had a potency to induce the ECF production from T lymphocytes from normal donors when the cells were stimulated by the supernatants, which suggests that a monocyte‐derived soluble factor (MDF) stimulated T lymphocytes to produce an ECF resembling this spontaneously produced ECF from the patients. MDF seemed to be a synthesized protein by the cells. Gel filtration indicated that molecular weight of MDF ranged between 70,000 and 100,000. MDF activity was stable at 56° for 30 min but labile at 80° for 30 min. MDF failed to show detectable IL‐1 and IL‐2 activity. Furthermore, supernatants of stimulated monocytes by lipopolysacchride or silica particles failed to show ECF‐producing activity, whereas they showed evident lymphocyte‐activation activity. Neither recombinant IL‐1 nor IL‐2 had ECF and ECF‐producing activity. From the present experiments, it was suggested that MDF was at least partly involved in the induction of ECF production by OKT4‐positive T lymphocytes in patients with hypereosinophilia.

ISSN:0741-5400    

DOI:10.1002/jlb.43.6.520

出版商:Wiley    

年代:1988

数据来源: WILEY

摘要:

AbstractDelayed‐type hypersensitivity (DTH) responses were suppressed in female mice treated with diethylstilbesterol (DES), a synthetic nonsteroidal compound possessing estrogenic activity, but not in male mice. Upon analysis of this DTH‐suppression in DES‐treated female mice by use of the macrophage migration inhibition (MI) assay, an in vitro correlate of DTH, suppressor adherent cells (i.e., macrophages) in the peritoneal cavity were found to play an important role in this DTH suppression. On the other hand, DES‐induced suppression was observed in surgically castrated male mice with depressed plasma testosterone (TS) levels, but not in TS‐treated female mice or in castrated male mice, which suggests that TS inhibited the DES suppression. These results provide evidence that DTH response may be modulated by sex hormones.

ISSN:0741-5400    

DOI:10.1002/jlb.43.6.530

出版商:Wiley    

年代:1988

数据来源: WILEY

摘要:

AbstractMouse peritoneal macrophages formed attachments with β‐glucuronidase deficient human fibroblasts within an hour after co‐cultures were initiated. Some of these attachments were transitory, while in others macrophages remained in firm contact with fibroblasts for many hours. Attachment of one macrophage did not prevent attachment of others, since many fibroblasts made firm contact with four or five other cells. Not all macrophages, however, attached themselves to fibroblasts. Macrophages injected with Lucifer yellow did not transfer the dye to fibroblasts with which they had made contact, nor was there any reverse transfer from injected fibroblasts to macrophages. Lucifer yellow was, however, transferred rapidly from injected fibroblasts to other adjacent fibroblasts with which they had formed gap junctions. Macrophages whose lysosomes had been pre‐loaded with FITC‐dextran did transfer this ligand to recipient fibroblasts, where it became localised in a perinuclear pattern with many bright punctate patches adjacent to donor macrophages. Transfer of FITC‐dextran was blocked when cells were separated by nucleopore membranes in an analogous manner to transfer of endogenous lysosomal β‐glucurondiase.

ISSN:0741-5400    

DOI:10.1002/jlb.43.6.539

出版商:Wiley    

年代:1988

数据来源: WILEY

摘要:

AbstractBacterial lipopolysaccharide (LPS) has previously been shown to enhance a number of chemoattractant‐induced responses by human neutrophils. The possible role of elastase, a neutral protease with broad substrate specificity, in neutrophil‐mediated vascular injury of a variety of diseases prompted us to examine a) whether or not LPS enhances the direct chemoattractant‐induced secretion of elastase, b) the quantitative requirements of LPS and chemotactic factors, and c) some structural requirements of LPS for this effect. Our results show that LPS at 10 ng/ml and above, enhanced formyl‐methionyl‐leucyl‐phenylalanine‐induced neutrophil secretion of elastase, as well as secretion of myeloperoxidase and vitamin B12‐binding protein. This effect was independent of cytochalasins or surface stimulation, and thus may occur during chemotactic factor stimulation in vivo. LPS also enhanced neutrophil secretory responses to the complement fragments C5a, C5a des arg, and, to a lesser degree, to leukotriene B4and platelet‐activating factor. This enhancement effect appeared to require the presence of the lipid A moiety and/or parts of the core polysaccharide but not the O‐antigen portion of the LPS molecule. Our findings identify a possible LPS‐dependent mechanism of neutrophil elastase‐mediated tissue injury in Gram‐negative infections.

ISSN:0741-5400    

DOI:10.1002/jlb.43.6.547

出版商:Wiley    

年代:1988

数据来源: WILEY

摘要:

AbstractAttempts to analyze bone marrow‐derived macrophages (BMDM) by flow cytometry have been prohibited because of their high autofluorescence. Using an autofluorescence reduction method of Steinkamp and Stewart to reduce the autofluorescence of BMDM, we were able to examine several macrophage populations for their expression of I‐A, I‐J, and Mac‐1 cell surface determinants. Bone marrow cells examined immediately after removal from the femur contain 50–60% Mac 1‐positive cells (mainly granulocytes). During the next few days granulocytes and nonmacrophage precursor cells die, and the number of Mac 1‐positive cells decrease. Once the bone marrow cells have been maintained in L cell conditioned medium (LCM) for 2 to 3 days, the number of cells expressing Mac 1 increases rapidly from 20% to 98% during the next 3 to 4 days. Bone marrow cells grown in LCM do not express I‐J until these cells have been in culture 3 to 4 days, and the number of cells expressing I‐J (up to 90% positive) parallels the increase in macrophages. Bone marrow cells maintained in LCM did not express detectable I‐A during the 14 days these cells were examined. Two other macrophage populations often used in a variety of immunological studies were analyzed by flow cytometry. We found that the majority (up to 80%) of peritoneal cells expressed I‐A, and only 20% of peritoneal cells had I‐J cell surface determinants. On the other hand, peritoneal exudate cells collected 4 days after thioglycolate medium treatment were predominantly I‐J positive (up to 70%), and only about 30% of these cells expressed I‐A cell surface antigens.The binding of anti‐I‐J IgM antibody to BMDM was not to Fc receptors because pretreating these cells with up to 25 μg of an IgG2amyeloma protein did not block anti‐I‐J antibody binding. The addition of 25‐200 μg of monoclonal anti‐Fc receptor antibody was also ineffective in blocking the binding of a monoclonal anti‐I‐Jkantibody to BMDM. Pretreatment of BMDM with the IgM fraction of several control IgM antibody preparations did not block the specific binding of fluoresceinated anti‐I‐J IgM antibody.BMDM provide a pure population of macrophages that express a significant level of cell surface I‐J antigens. Bone marrow cells grown in LCM are essentially devoid of other contaminating cells, and the increase in the number of I‐J‐positive cells parallels the increase in macrophages in these cultures. Thus, the further study of BMDM may permit resolution of questions raised by molecular biologists and immunologists regarding the nature of the I‐J protein, the location of I‐J genes, and the role of I‐J in regulating immune responses.

ISSN:0741-5400    

DOI:10.1002/jlb.43.6.557

出版商:Wiley    

年代:1988

数据来源: WILEY

ISSN:0741-5400    

DOI:10.1002/jlb.43.6.567

出版商:Wiley    

年代:1988

数据来源: WILEY