bluuebunny/crossref_metadata_2025 huggingface dataset:
Regulation of cytokine expression in macrophages and the Langerhans cell-like line XS52 by calcitonin gene-related peptide
Authors: Torii Hideshi , Hosoi Junichi , Beissert Stefan , Xu Shan , Fox Floyd E , Asahina Akihiko , Takashima Akira , Rook Alain H , Granstein Richard D
Published: January 2018

Calcitonin gene-related peptide (CGRP) inhibits antigen presentation by Langerhans cells (LC) and macrophages, and LC are anatomically associated with CGRP-containing epidermal nerves. To determine whether CGRP may produce some of its functional effects through regulation of cytokine expression, we utilized enzyme-linked immunosorbent assay (ELISA) of conditioned supernatants to examine production of interleukin (IL)-10 and IL-1β protein in the LC-like cell line XS52 as well as the reverse transcriptase-polymerase chain reaction (RT-PCR) to examine levels of mRNA for IL-10, IL-1β, and the 40-kDa subunit (p40) of IL-12. CGRP augmented the lipopotysaccharide (LPS) and granulocyte-macrophage colony-stimulating factor (GM-CSF) -induced release of IL-10 protein and the induced expression of IL-10 mRNA in these cells. However, it suppressed the induction of release of IL-1β protein and the induction of mRNA for IL-12 p40 and IL-1β by LPS and GM-CSF. Regulation of cytokine expression in peritoneal macrophages was also examined. By ELISA, the LPS-induced expression of IL-10 was augmented by CGRP, whereas the induction of IL-1β was suppressed. Northern analysis demonstrated augmentation of LPS-induced IL-10 mRNA levels and inhibition of LPS-induced IL-1β mRNA by CGRP. CGRP inhibited the LPS-induced induction of IL-12 mRNA as assessed by RT-PCR. Up-regulation of B7-2 expression by LPS and GM-CSF was suppressed by CGRP in both XS52 cells and macrophages, as previously reported. This suppression, however, could be abrogated by co-culture with neutralizing antibodies to IL-10. Furthermore, the presence of neutralizing antibodies to IL-10 during exposure of epidermal cells (EC) to CGRP prevented the CGRP-mediated suppression of EC presentation of tumor-associated antigens (from the S1509a spindle cell carcinoma) for elicitation of delayed-type hypersensitivity in S1509a-immune mice. These data suggest that suppression of antigen-presenting function by CGRP is mediated, at least in part, by changes in cytokine expression that favor less robust antigen presentation for cell-mediated immunity.
Immunosuppressive retroviral peptides: Immunopathological implications for immunosuppressive influences of retroviral infections
Authors: Haraguchi Soichi , Good Robert A , Cianciolo George J , Engelman Robert W , Day Noorbibi K
Published: January 2018

Studies of the effects of retroviruses on the immune system, which date back through thirty years of investigations, are reviewed. In the earliest published studies in the 1960s, it was demonstrated that mice infected with oncogenic viruses were immunosuppressed. Since then, numerous articles have been published describing profound immunodeficiencies observed in vivo in humans infected with human immunodeficiency virus and in animals such as cats infected with the feline immunodeficiency virus. In vitro investigations have shown that inactivated retroviruses or transmembrane envelope protein pl5E as well as a synthetic 17-amino acid peptide (CKS-17) impressively conserved within the transmembrane envelope protein of several animal or human retroviruses are highly immunosuppressive. More recently, dysfunction of cytokines produced by CKS-17 at both a cellular and molecular level have been found to mimic influences observed in vivo in patients infected with the human immunodeficiency virus. CKS-17 has also been shown to induce cAMP in vitro. The significance of these observations to understanding the immunological disturbances observed in malignancy, cytokine biosynthesis, and modulations of immune functions through cAMP is discussed.
IL-13 acts on macrophages to block the completion of reverse transcription, inhibit virus production, and reduce virus infectivity
Authors: Montaner Luis J , Bailer Robert T , Gordon Siamon
Published: January 2018

An understanding of the immune suppression of HIV-1 replication in macrophages continues to be a major goal of AIDS research due to the central role this cell type has in AIDS pathogenesis. We have previously discussed the potential clinical benefits of the anti-inflammatory cytokine interleukin-13 (IL-13), which, unlike IL-4 or IL-10, has limited effects on T cell functions. In this report we extend our observations on the effects of IL-13 on HIV-1 replication in monocyte-derived macrophages (MDM) and show redundancy with IL-4. IL-13 or IL-4 have similar effects on HIV-1 replication in MDM when added at different times after infection, with the ability to decrease infectious virus release when added for up to 7 days after infection. Removal of IL-13 from MDM revealed a reduction of infection by 16- to 81-fold based on the absence of viral re-emergence from lower multiplicity of infection (m.o.i.). The reduction of HIV-1 infectivity in MDM caused by IL-13 was further characterized by studies on the formation of viral DNA over a range of m.o.i. IL-13 increased the formation of LTR DNA at the lowest m.o.i. of 0.007 while concurrently inhibiting the formation of gag DNA, a later reverse transcription product, at the highest m.o.i. tested, 0.62. Overall, our data indicate that IL-13 can act on macrophages before and after HIV-1 infection by blocking the completion of reverse transcription, decreasing virus production, and reducing the infectivity of the progeny virions.
Macrophage tropism: fact or fiction?
Authors: Stent Gianna , Joø Gun-Britt , Kierulf Peter , Åsjö Birgitta
Published: January 2018

Primary HIV-1 isolates can be distinguished by phenotypic qualities such as the ability to productively infect cells of established CD4-positive lines and to induce syncytia in MT-2 cells. Such viral phenotypes have also been reported to confer host cell specificity. It is perceived that primary isolates with the syncytium-inducing phenotype (SI or rapid/high) are T cell tropic and are therefore unable to infect primary cells of the monocyte/macrophage lineage. However, we have consistently found that these isolates are as capable of establishing infection in monocyte-derived macrophages (MDM) as the monocytotropic, non-syncytium-inducing variants (NSI or slow/low). It is known that differentiation, activation, and proliferation of human monocytes are affected by both isolation methods and culture conditions. Therefore, to test whether our inability to discriminate macrophage tropic HIV-1 isolates could be explained by differences in culturing techniques, we isolated monocytes by elutriation or short-term adherence and allowed the cells to mature and differentiate in either the presence or absence of autologous lymphocytes. After removal of nonadherent cells, MDM were infected with a panel of SI and NSI primary HIV-1 isolates. MDM were susceptible to infection by the SI as well as the NSI isolates, regardless of whether or not the cells were allowed to mature in the presence of autologous lymphocytes. However, MDM matured in the presence of autologous lymphocytes replicated HIV-1 isolates (both NSI and SI) to a higher titre than MDM matured in the absence of lymphocytes. In light of these findings and recently published reports on HIV-1 phenotype and chemokine receptor usage we believe that the term macrophage-tropic strains of HIV-1 is no longer appropriate.
Mechanisms of loss of functional dendritic cells in HIV-1 infection
Authors: Knight Stella C , Elsley William , Wang Hong
Published: January 2018

Dendritic cells (DC) are lost from blood and skin during infection with HIV-1; those remaining show a reduced capacity to stimulate T cell proliferation [S. C. Knight, AIDS 10, 807–817]. Our recent studies investigate mechanisms underlying these effects. DC exposed to HIV-1 in vitro can act as targets for cytotoxic T cells, although optimal killing was not obtained until DC were exposed to HIV-1 for 3 days. This cytotoxicity may provide a feedback mechanism by which DC that have presented antigens are removed. However, this effect could also contribute to the reduction in DC during persistent infection. We have also investigated the effect of exposure to HIV-1 on DC function. DC exposed to HIV-1IIIB virus for 2 h stimulated primary proliferative and cytotoxic T cell responses in vitro; these effects may be similar to those occurring during the early activation of protective antiviral immunity in vivo. After exposure of DC to virus for 5 days, stimulation of allogeneic T cells was reduced. However, a different situation applied when using DC developed from CD34+ cord blood stem cells under the influence of granulocyte-macrophage colony-stimulating factor and tumor necrosis factor a that were exposed at 24 h to the same virus. These DC showed low levels of infection similar to peripheral blood DC but in contrast stimulated normal allogeneic T cell proliferation. The capacity of DC exposed to HIV-1 to stimulate T cell proliferation or to show a blocked stimulatory capacity may thus depend not only on the length of the exposure to virus but also on the maturational state of the DC. Loss in DC numbers and function on exposure to HIV-1 may result in lower levels of stimulation of T cells, which in turn may be instrumental in reduction of T cell numbers.
HIV-1 viral protein R (Vpr) regulates viral replication and cellular proliferation in T cells and monocytoid cells in vitro
Authors: Ayyavoo Velpandi , Mahalingam S , Rafaeli Yosef , Kudchodkar Sagar , Chang David , Nagashunmugam T , Williams William V , Weiner David B
Published: January 2018

Among the putative accessory genes of HIV-1, the 96-amino-acid virion-associated vpr gene product has been described to have several novel biological activities. These include cytoplasmic-to-nuclear translocation, which empowers HIV to infect and replicate in non-dividing cells and to increase viral replication, particularly in macrophages. Along with these viral effects, we found that HIV-1 Vpr induces dramatic biological changes in the target cells of HIV infection, including induction of changes in transcriptional patterns, morphological changes, and complete inhibition of proliferation, which collectively was termed differentiation. These changes occur in the absence of other viral gene products, suggesting that Vpr mediates its proviral effects partially or perhaps solely through modulation of the state of the target cell rather than directly on the virus. The inhibition of proliferation in T cell lines has been extended by several groups to demonstrate that the inhibition of proliferation is through G2 cell cycle arrest, further supporting the idea that Vpr acts directly on cellular targets. We have recently described a role for Vpr in modulating the glucocorticoid pathway, which is involved in the regulation of the state of the cell, in cytoplasmic-to-nuclear translocation, and in modulation of host cell transcription. It is important to note that certain anti-glucocorticoid compounds modulate Vpr activity in vitro. These results support the idea that the host cell contains specific receptor molecule(s) through which Vpr mediates its activity. Consequently, Vpr represents a unique target for anti-HIV drug development and has significance for HIV-1 disease progression.
Tumor site-selective localization of an adoptively transferred T cell line expressing a macrophage lectin
Authors: Ichii Shinji , Imai Yasuyuki , Irimura Tatsuro
Published: January 2018

CTLL-2 cells were transfected with an expression vector that contained cDNA of a mouse macrophage galactose/N-acetylgalactosamine-specific calcium-type lectin (MMGL) and a stable transfectant (CTL-ML) was established. These cells and mock transfectant cells (CTL-CEP) were labeled with a long-term fluorescent cell tracer, DiI. The labeled cells were intravenously injected into mice that contained established lung metastases produced by OV2944-HM-1 ovarian tumor cells. Analyses with fluorescence microscopy of a series of frozen lung sections from the recipient mice revealed that CTL-ML preferentially accumulated in the lung metastatic nodules, whereas CTL-CEP did not Time course studies showed that the preferential accumulation was evident 3 days after adoptive transfer. We also found that OV2944-HM-1 cells bound peanut agglutinin and Vicia villosaagglutinin B4, whose sugar specificity overlaps with the specificity of MMGL. These results suggested that MMGL molecules expressed on CTLL-2 cells contributed to their selective trafficking or retention in tumor foci possibly through recognition of tumor-associated cell surface carbohydrate antigens. These results also suggested that MMGL could be used for the selective targeting of effector cells in adoptive immunotherapy.
Menstrual- and gender-dependent variations in circulating IL-1 agonists, antagonists, and binding proteins
Authors: Cannon Joseph G , Abad Leslie W , Vannier Edouard , Lynch Elizabeth A
Published: January 2018

This study tested the hypotheses that sex-related differences in circulating binding proteins for interleukin-1 β (IL-1 β) exist and that these binding proteins affect immunoassays for IL-1 β and IL-1Ra. 125I-labeled IL-1 β was added to human plasma samples, then chromatographed. The percentages of total radioactivity eluting in a high-molecular-weight peak were 21.0 + 0.8 for men (n = 6), 19.1 ± 0.9 for follicular phase women (n = 6), and 18.0 ± 0.8 in luteal phase women (n = 6; men vs. women, P = 0.032; follicular vs. luteal, P = 0.035), and correlated with plasma sIL-1RII concentrations (r = 0.647, P = 0.007). Plasma IL-1 β immunoreactivity did not correspond to concurrent cellular secretion rates due, in part, to interference in the IL-1 β assay by sIL-1RII. Correspondence between plasma IL-1Ra levels and cellular secretion rates was observed only after serial dilutions of the samples. These results indicate that plasma IL-1 β binding capacity differs between men and women and that sIL-1RII is a major contributing factor. Furthermore, relating plasma IL-1 isoform immunoreactivity to functional measures (tracer binding) or concurrent release by isolated cells can lead to insights about assay interferences that may exist in plasma.
Nω-nitro-L-arginine methyl ester inhibits inflammatory liver injury induced by interleukin-2
Authors: Lentsch Alex B , Edwards Michael J , Sims David E , Miller Frederick N
Published: January 2018

Administration of interleukin-2 (IL-2) for treatment of metastatic disease often results in inflammatory liver injury. Previous studies have implicated increased leukocyte and platelet adhesion and enhanced nitric oxide production as causative factors in the development of IL-2-induced hepatic injury. This study investigated the capacity of Nω-nitro-L-arginine methyl ester (L-NAME), a nitric oxide synthesis inhibitor, to limit IL-2-induced hepatic edema and hepatocellular damage in mice. Using hepatic intravital microscopy, we also examined the effects of L-NAME on IL-2-induced increases in leukocyte and platelet adhesion. Administration of IL-2 increased leukocyte and platelet adhesion in postsinusoidal venules and decreased hepatic perfusion. Cotreatment with L-NAME had no effect on leukocyte adhesion but increased platelet-endothelial adhesion and microvascular thrombosis. Chronic IL-2 treatment induced hepatic edema and hepatocellular injury. However, coadministration of L-NAME attenuated IL-2-induced edema and completely inhibited hepatocellular damage. These findings suggest that nitric oxide may play a central role in IL-2-induced inflammatory liver injury.
Oxidant inhibition of αLβ2 integrin adhesion: evidence for coordinate effects on conformation and cytoskeleton linkage
Authors: Edwards Bruce S , Southon Eileen A , Curry Mark S , Salazar Francisco , Gale James M , Robinson Martyn K , Graf Lloyd H , Born Jerry L
Published: January 2018

Dithiothreitol (DTT) and other dithiol antioxidants with closely spaced thiol pairs strongly activate leukocyte function antigen-1 (LFA-1, αLβ2 integrin) to bind intercellular adhesion molecule-1 (ICAM-1). Because direct biochemical modification of LFA-1 by DTT is not apparently involved, we investigated the possible role of a reduction-oxidation (redox)-sensitive adhesion-regulatory pathway. Phenylarsine oxide (PAO), an oxidant selectively reactive with closely spaced pairs of thiol groups, inhibited LFA-1-dependent adhesion of human natural killer and HSB2 T leukemia cells to murine cells expressing human ICAM-1. PAO also induced disappearance of a conformation-sensitive LFA-1 epitope recognized by KIM127 antibodies and promoted an increase in total apparent cytoskeleton-linked LFA-1 in which a novel cytochalasin D-resistant linkage was involved. Exposure of PAO-pretreated cells to DTT caused a decline in LFA-1/cytoskeleton linkages in conjunction with rapid restoration of KIM127 epitope expression and LFA-1 adhesive function. Implicating an intracellular site of action were findings that (1) an epitope-tagged PAO probe bound predominantly to intracellular proteins but not detectably to immunoprecipitation-purified LFA-1 chains, and (2) membrane permeant but not impermeant dithiol antioxidants reversed PAO adhesion-inhibitory effects. These results support the concept of a reversible redox-sensitive linkage between LFA-1 and cytoskeleton by which oxidants and antioxidants may exert profound opposing effects on LFA-1 conformation and adhesive function.
Collagenase expression by normal human eosinophils
Authors: Shlopov Boris V , Hasty Karen A
Published: January 2018

Collagenolytic activity was detected in extracts from human blood eosinophilic granulocytes. To characterize this collagenase, we compared extracts from isolated populations of eosinophils and neutrophils. Significant collagenase activity against type I and II collagens was present in extracts from both cell populations. Although collagenase activity was present in eosinophils, the cells did not stain with antibodies specific for fibroblast, neutrophil collagenase, or collagenase-3. In contrast, neutrophils immunostained positively with antibody to neutrophil collagenase. Western blot analysis confirmed the presence of immunoreactive protein in neutrophil extracts but not in the eosinophil extracts. Reverse transcription-polymerase chain reaction using primers specific for all three known collagenases of an eosinophil cell suspension from peripheral blood that had 3% contamination with immature neutrophils showed a polymerase chain reaction product only with neutrophil collagenase oligonucleotide primers, but not with fibroblast collagenase or collagenase-3 primers. Eosinophil collagenase would appear to have a unique antigenic structure and may represent a new enzyme.
Modulation of neutrophil adherence to endothelial cells by platelet-derived adherence-inhibiting factor through interactions with selectin molecules
Authors: Iwabuchi Kazuhisa , Nagaoka Isao , Yamashita Tatsuhisa
Published: January 2018

Platelet-derived adherence-inhibiting factor (AIF) has been demonstrated to regulate the neutrophil binding to type IV collagen. In this study, we have examined the effect of AIF on neutrophil adherence to confluently cultured human umbilical vein endothelial cells (EC). AIF inhibited neutrophil adherence to thrombin- or tumor necrosis factor α (TNF-α)-stimulated EC by 75 or 43%, respectively, but hardly affected neutrophil adherence to resting EC. It is interesting to note that the inhibitory activity of AIF was reduced by N-formyl-methionyl-leucyl-phenylalanine (fMLP) stimulation of neutrophils. Pretreatment of neutrophils or EC with AIF inhibited neutrophil adherence to thrombin- or TNF-α-stimulated EC, suggesting that neutrophils and EC have AIF-binding proteins. Using AIF-Sepharose affinity chromatography, AIF-binding proteins containing L-selectin were isolated from 125I-labeled resting neutrophils. However, L-selectin was markedly decreased in the AIF-binding fraction from fMLP-stimulated neutrophils. With the use of AIF-affinity chromatography, P- and E-selectins were obtained in the AIF-binding fractions from resting, thrombin-, and TNF-α-stimulated EC. It is important to note that P- and E-selectin were greatly increased in the AIF-binding fractions from thrombin- and TNF-α-stimulated EC, respectively. Furthermore, AIF was able to bind to L-selectin-IgG chimeric protein and inhibit the binding of chimeric protein to thrombin- or TNF-α-stimulated EC. In addition, AIF inhibited the binding of anti-P- or anti-E-selectin monoclonal antibody to the lysates of thrombin- or TNF-α-stimulated EC. Together these observations indicate that AIF could recognize L-, P-, and E-selectins, and modulate neutrophil adherence to EC through interactions with selectin molecules.
Monoclonal antibodies to the common γ-chain as cytokine receptor antagonists in vivo: effect on intrathymic and intestinal intraepithelial T lymphocyte development
Authors: Malek Thomas R , Levy Robert B , Adkins Becky , He You-Wen
Published: January 2018

Mice lacking a functional γc subunit of cytokine receptors exhibit profound defects in the development of multiple lymphoid lineages. To investigate the role of γc-dependent cytokines in T cell development, the phenotype of developing T cells was compared in interleukin (IL)-7Rα-deficient mice and anti-γc mAb-treated chimeric mice reconstituted with adult bone marrow cells or subsets of pro-T cells. These studies indicate that γc contributes to T cell development at multiple stages of pro-T cell maturation and that IL-7/IL-7R is the primary cytokine for thymic-dependent T cell development. However, our data also implicate other γc-dependent cytokines during thymic T cell development. By contrast, substantial intestinal intraepithelial lymphocytes (IEL) development was observed in the intestinal intraepithelium in both types of mice. Analysis of IL-7Rα-deficient mice indicates that the IL-7/IL-7R system is critical only for the development of TCR γδ+ IEL. However, the inhibitory activity of the anti-γc mAb in the chimeric mouse model suggests that additional γc-utilizing cytokines regulate the development of the remaining subsets of IEL.
Superoxide production by phagocytosing macrophages in relation to the intracellular distribution of oxygen
Authors: James Philip E , Grinberg Oleg Y , Swartz Harold M
Published: January 2018

We simultaneously measured the concentration of oxygen ([O2]) within the phagosomal and extracellular compartments of macrophages. By combining electron paramagnetic resonance (EPR) oximetry techniques with that of spin-trapping, we found that a significant difference in oxygen concentration ([O2]) exists between these two compartments and we were able to monitor (1) how [O2] in the extracellular compartment and the rate of mitochondrial consumption affected this difference in [O2], and (2) to what extent this gradient of [O2] influenced production of reactive oxygen species by phagosomes. Under conditions where the [O2] in the inflowing gas was high (210 μM; air), the [O2] in the extracellular and phagosomal compartments was 180 and 141 μM, respectively. This was sufficient to maintain maximum superoxide production in these cells. When extracellular [O2] was reduced to 84 or 36 μM, the [O2] in phagosomes within the cells (31.7 and 7.7 μM, respectively) was too low to maintain superoxide production by the NADPH-oxidase system within the phagosomes. The [O2] in the extracellular compartments of these samples, however, was always sufficient to maintain superoxide production by phagosomes at the cell surface. Our findings suggest that the distribution of oxygen surrounding and within macrophages can influence their ability to perform microbicidal and tumoricidal functions, even at an [O2] in the media that appears to be adequate. J. Leukoc. Biol. 64: 78–84; 1998.
Resident mast cells are important for eotaxin-induced eosinophil accumulation in vivo
Authors: Das Anuk M , Flower Roderick J , Perretti Mauro
Published: January 2018

Eotaxin administration intraperitoneally, but not into dorsal air-pouches, of ovalbumin-sensitized mice exhibiting blood eosinophilia induced a threefold increase in eosinophil (Eφs) infiltration. Transfer of 1 × 106 mixed peritoneal cavity cells (PCC), containing 3.5 to 4.5 × 104 mast cells (MC), from donor mice to air-pouches of sensitized (but not unsensitized) recipient mice, established an Eφ infiltration to eotaxin (vehicle, 0.86 ± 0.27 × 106; eotaxin, 1.63 ± 0.16 × 106 Eφs/air-pouch). Neutrophil numbers were also increased. When MC-depleted (−93%) PCC were injected into air-pouches of recipient animals, Eφ infiltration was not supported (−52%). Injection of macrophage-depleted (−99%) PCC into air-pouches elicited a full Eφ response to eotaxin but not neutrophil infiltration (−81%). Systemic dexamethasone treatment of recipient mice reduced Eφ accumulation; treatment of donor mice only reduced neutrophil accumulation. Our study points to a crucial role for MC in Eφ recruitment by eotaxin. J. Leukoc. Biol. 64: 156162; 1998.
In vivo regulation of PECAM-1 activity during acute endothelial dysfunction in the rat mesenteric microvasculature
Authors: Scalia Rosario , Lefer Allan M
Published: January 2018

The relationship between acute endothelial dysfunction and the extravasation of leukocytes was studied in vivo with intravital microscopy of the rat mesenteric microvasculature. Acute endothelial dysfunction of the rat mesenteric microvasculature was induced in vivo by superfusing the mesentery for 90 min with one of three different stimulating agents: NG-nitro-L-arginine methyl ester (l-NAME, 50 μM), thrombin (0.5 U/mL), or hydrogen peroxide (H2O2, 50 μM). All three agents induced a similar increase in leukocyte rolling and adherence, which was significantly greater than that observed in control rats superfused with Krebs-Henseleit solution (P < 0.01). Transendothelial migration of leukocytes into the perivascular space was also increased by superfusion with l-NAME, thrombin, or H2O2. However, there was a greater increase in the number of migrated leukocytes in the rat mesentery after l-NAME and H2O2 superfusion than that observed during thrombin superfusion. In vivo infusion of a neutralizing antibody against platelet-endothelial cell adhesion molecule-1 (PECAM-1) specifically inhibited l-NAME-induced and H2O2-induced migration of leukocytes but did not prevent extravasation of leukocytes induced by thrombin. In rat mesenteries superfused with the three different stimuli, immunohistochemical analysis of endothelial cell adhesion molecules expressed on the microvascular endothelium revealed a significant increase of ICAM-1, but not PECAM-1, endothelial cell surface expression (P < 0.01 and P > 0.05 vs. control rats, respectively). Our data confirm a key role for PECAM-1 acutely in leukocyte extravasation in vivo and indicate that the involvement of constitutively expressed PECAM-1 in leukocyte transendothelial migration is preferentially correlated to oxidative stress-related stimuli in the microvascular endothelium. J. Leukoc. Biol. 64: 163–169; 1998.
HIV load in highly purified CD8+ T cells retrieved from pulmonary and blood compartments
Authors: Semenzato Gianpietro , Agostini Carlo , Chieco-Bianchi Luigi , De Rossi Anita
Published: January 2018

The pulmonary microenvironment can be HIV infected from the asymptomatic period of HIV infection and it has been demonstrated that HIV presence elicits a discrete virus-specific CTL immune response in the lungs. In this study we analyzed T cell subsets and compared the proportion of CD8+ T cells harboring HIV in the lung and in the circulation of HIV-seropositive patients with T cell alveolitis. Proviral load was assessed using the DNA-polymerase chain reaction technique on highly purified CD8+ T cells isolated from peripheral blood and bronchoalveolar lavage. The proviral load of pulmonary CD8+ T cells showed an upward trend with respect to corresponding samples isolated from the peripheral blood of the same patients. J. Leukoc. Biol. 64: 298–301; 1998.
TNF and IL-6 mediate MIP-1α expression in bleomycin-induced lung injury
Authors: Smith Robert E , Strieter Robert M , Phan Sem H , Lukacs Nicholas , Kunkel Steven L
Published: January 2018

Previously, macrophage inflammatory protein-1α (MIP-1α), a member of the C-C chemokine family, has been implicated in bleomycin-induced pulmonary fibrosis, a model of the human disease idiopathic pulmonary fibrosis. Neutralization of MIP-1α protein with anti-MIP-1α antibodies significantly attenuated both mononuclear phagocyte recruitment and pulmonary fibrosis in bleomycin-challenged CBA/J mice. However, the specific stimuli for MIP-1α expression in the bleomycin-induced lesion have not been characterized. In this report, two mediators of the inflammatory response to bleomycin, tumor necrosis factor (TNF) and interleukin-6 (IL-6), were evaluated as putative stimuli for MIP-1α expression after bleomycin challenge in CBA/J mice. Elevated levels of bioactive TNF and IL-6 were detected in bronchoalveolar lavage (BAL) fluid and lung homogenates from bleomycin-treated CBA/J mice at time points post-bleomycin challenge, which precede MIP-1α protein expression. Treatment of bleomycin-challenged mice with soluble TNF receptor (sTNFr) or anti-IL-6 antibodies significantly decreased MIP-1α protein expression in the lungs. Furthermore, normal alveolar macrophages secreted elevated levels of MIP-1α protein in response to treatment with TNF plus IL-6 or bleomycin plus IL-6, but not TNF, bleomycin, or IL-6 alone. Finally, leukocytes recovered from the BAL fluid of bleomycin-challenged mice secreted higher levels of MIP-1α protein, compared to controls, when treated with TNF alone. Based on the data presented here, we propose that TNF and IL-6 are part of a cytokine network that modulates MIP-1α protein expression in the profibrotic inflammatory lesion during the response to intratracheal bleomycin challenge. J. Leukoc. Biol. 64: 528–536; 1998.
The significance of zinc for leukocyte biology
Authors: Wellinghausen Nele , Rink Lothar
Published: January 2018

Zinc is an essential element important for growth, the nervous system, and especially the immune system. Zinc deficiency as well as levels well above normal, due to high-dose treatment, showed an impaired immune function. This review summarizes the current status of zinc's significance for leukocyte biology and health. In detail, the physiology of zinc and the impaired immune functions in zinc deficiency syndromes are described. The regulation of innate immunity as well as the function and maturation of lymphocytes and monocytes is critically discussed as a system dependent on the zinc concentration in vivo and in vitro. Furthermore, the influence of zinc on experimental systems as well as on widely used immunostimulants is described, showing the importance of the knowledge of zinc concentration in in vitro leukocyte studies. The specific interactions of zinc with immunologically important serum proteins, signal transduction components, and membrane functions is summarized, showing the molecular basis of this interaction as known so far. Finally, the therapeutic use of zinc is critically discussed with new aspects also using the immunosuppressive effects of zinc. In conclusion, these data show that the zinc concentration should be taken into account whenever complex alterations of immune functions are observed. J. Leukoc. Biol. 64: 571–577; 1998.
Instillation of allogeneic lung macrophages and dendritic cells cause differential effects on local IFN-7 production, lymphocytic bronchitis, and vasculitis in recipient murine lungs
Authors: Wilkes David S , Thompson Linda K , Cummings Oscar W , Bragg Shanda , Heidler Kathleen M
Published: January 2018

Lung allograft rejection is believed to be initiated by donor lung accessory cells, namely macrophages and dendritic cells, interacting with recipient lymphocytes leading to up-regulated Th1 type (IFN-γ) cellular immunity culminating in graft destruction. The purpose of this study was to determine the individual role of donor lung macrophages and dendritic cells in the rejection response. Utilizing a murine model that reproduces the immunology and histology of acute rejection, C57BL/6 mouse (I-ab, H-2b) lung dendritic cells (DC-enriched lung cells), purified alveolar macrophages (I-a-negative macrophages), or various ratios of I-a-negative macrophages/DC were instilled into BALB/c mouse (I-ad, H-2d) lungs followed by an assessment of local IFN-γ production and grading of rejection pathology. The data show that DC, and not I-a-negative macrophages, induced IFN-γ production in recipient lungs. However, the local production of IFN-γ was not always associated with histological changes characteristic of rejection pathology. In contrast to either cell type alone, instillation of C57BL/6 I-a-negative macrophages and DC, together, were required to induce rejection pathology in BALB/c lungs. In addition, the rejection response was dependent on interactions between donor I-a-negative macrophages and DC. J. Leukoc. Biol. 64: 578–586; 1998.
The murine homolog of the HIN 200 family, Ifi 204, is constitutively expressed in myeloid cells and selectively induced in the monocyte/macrophage lineage
Authors: Gariglio Marisa , De Andrea, Marco , Lembo Marianna , Ravotto Monica , Zappador Claudio , Valente Guido , Landolfo Santo
Published: January 2018

To examine the expression of Ifi 200 genes in vivo and add new information about their function, polyclonal monospecific rabbit antibodies, designated N-term or C-term, were raised against both the N-terminus and C-terminus of the 204 protein (p204) respectively. Western blotting analysis demonstrated that p204 and D3, another member of the Ifi 200 gene family, are constitutively expressed, though at different degrees, in bone marrow, thymus and lymph nodes, and barely detectable in the spleen. Poly rI:rC treatment did not modulate their expression. Peritoneal resident macrophages (Mϕ) from untreated mice were negative, but displayed high levels of both p204 and D3 on poly rI:rC treatment. A significant increase of these proteins is also observed when Mϕ are cultured overnight in vitro with IFNs or LPS. Lung, kidney and brain were negative for p204 and D3 expression. These results, together with immunois-tochemical analysis, demonstrate that the 204 gene has an expression pattern restricted to cells of the myelomonocytic lineage similar to that observed for the human homolog, the myeloid nuclear differentiation antigen (MNDA) suggesting its potential involvement in the differentiation and maturation of this cell lineage. J. Leukoc. Biol. 64: 608–614; 1998.
Effects of platelet release products on neutrophilic Fcγ receptors
Authors: Sakamoto Noriko , Sakamoto Haruhiko , Tanaka Sumiko , Oryu Makoto , Ogawa Yoshitada
Published: January 2018

Large and small macromolecular activators of phagocytosis from platelets (l-MAPP and s-MAPP, respectively), which function via the neutrophilic Fcy receptors (FcγR) were refined from platelet release products by gel filtration and affinity chromatography with the use of an anti transferrin antibody column and the mechanism of phagocytosis activation was investigated. Flow cytometry revealed that l-MAPP and s-MAPP did not increase the expression of neutrophilic FcγRII (CD32) and FcγRIII (CD16) antigens, whereas rosette formation of neutrophils with rabbit IgG-sensitized sheep erythrocytes (EA) in the presence of anti FcγR antibodies suggested that both MAPPs increase the binding ability of FcγRII. On the other hand, the enhancing effect of l-MAPP and s-MAPP on neutrophilic phagocytosis disappeared with the increase in phagocytosis by the phosphate-buffered saline control neutrophils when they were centrifuged with EA before incubation for phagocytosis. The enhanced phagocytosis, both by the two MAPPs and centrifugation, was canceled by treatment of the neutrophils with anti-CD32 Fab. The phagocytosis activatory effects of MAPP on neutrophils were canceled by anti-CD71 monoclonal antibody but not by transferrin. J. Leukoc. Biol. 64: 631–635; 1998.
Signaling in neuropeptide-induced migration of human eosinophils
Authors: Dunzendorfer Stefan , Meierhofer Christian , Wiedermann Christian J
Published: January 2018

At inflammatory sites, leukocytes may confront multiple, competing chemoattractive signals. We compared the chemotactic potencies of several sensory neuropeptides with regard to signal transduction pathways in eosinophils. Eosinophils were enriched using magnetic cell sorting and migration was assayed in a Boyden microchemotaxis chamber. We found stimulatory effects of substance P, calcitonin gene-related peptide (CGRP), secretoneurin, vasoactive intestinal peptide (VIP), and secretin on eosinophil migration. Actions of VIP are predominantly mediated via VIP receptor type I. Migration toward secretoneurin, VIP, and secretin was blocked by a phosphodiesterase inhibitor, which, in contrast failed to affect substance P- and CGRP-induced eosinophil chemotaxis. Wortmannin blunted the migratory responses induced by all neuropeptides tested and substance P-induced effects on eosinophils were tyrphostin-23-sensitive. We conclude that substance P, CGRP, secretoneurin, and VIP/secretin stimulate eosinophil migration involving wortmannin-sensitive enzymes. Moreover, secretoneurin and VIP/secretin require additional activation of phosphodiesterases to stimulate eosinophil migration. J. Leukoc. Biol. 64:828–834; 1998.
Bacterial phagocytosis activates extracellular signal-regulated kinase and p38 mitogen-activated protein kinase cascades in human neutrophils
Authors: McLeish Kenneth R , Klein Jon B , Coxon Patricia Y , Head Kimberly Z , Ward Richard A
Published: January 2018

The hypothesis that bacterial phagocytosis by human polymorphonuclear neutrophils (PMNs) stimulates MAPK cascades that regulate respiratory burst activation was tested. Extracellular response kinase (ERK) and p38 kinase, but not c-Jun NH2-terminal kinase, activities were increased within 5 min of phagocytosis of plasma-opsonized Staphylococcus aureus (S-SA), reached maximum at 20–30 min, and remained elevated through 60 min. The role of Fcγ receptors was examined using gamma globulin-opsonized SA (IgG-SA), whereas CR3 receptors were activated by particulate β-glucan. IgG-SA stimulated a maximal ERK activity at 30 min, whereas p38 activity was maximal at 5 min. β-glucan stimulated maximal ERK activity at 5 min and maximal p38 activity at 2 min. Non-opsonized bacteria were ingested at 10% of the level of S-SA and stimulated a minimal increase in ERK and p38 activity at 60 min. S-SA stimulation of ERK was inhibited by wortmannin, LY294002, and genistein, but not calphostin C; whereas p38 stimulation was inhibited by calphostin C and genistein, but not wortmannin and LY294002. Simultaneous measurement of phagocytosis and H2O2 production by flow cytometry was used to assess the role of ERKs and p38 kinase in phagocytosis. The MEK inhibitor PD098059 had no significant effect on phagocytosis or H2O2 production. The p38 kinase inhibitor SB203580 significantly attenuated H2O2 production, whereas phagocytosis was unaffected. In conclusion, bacterial phagocytosis stimulates ERK and p38 activation by distinct signal transduction pathways. Phagocytosis-stimulated p38 kinase activity is necessary for optimal H2O2 production. J. Leukoc. Biol. 64: 835–844; 1998.
MIC-1 is a novel TGF-β superfamily cytokine associated with macrophage activation
Authors: Fairlie W D , Moore A G , Bauskin A R , Russell P K , Zhang H-P , Breit S N
Published: January 2018

As part of a study to identify novel genes associated with macrophage activation, we have cloned a new member of the transforming growth factor β (TGF-β) superfamily designated macrophage inhibitory cytokine 1 (MIC-1). MIC-1 is synthesized as a 62-kDa intracellular protein, which, after cleavage by a furin like protease, is secreted as a 25-kDa disulfide-linked dimeric protein. Sequence analysis indicates that it does not cluster within any existing TGF-β families, suggesting it may be the first member of a new grouping within the TGF-β superfamily. Tissue Northern blots show that MIC-1 transcripts are only found abundantly in placenta, although smaller amounts are seen in a limited number of other adult and fetal tissues. MIC-1 is not expressed in resting macrophages but is induced by a number of different activation agents, including phorbol myristate acetate, interleukin 1, tumor necrosis factor α, and macrophage colony-stimulating factor but not by lipopolysaccharide or interferon-γ. We have hypothesized that it may be an autocrine inhibitor of macrophage activation but its major biological role is still uncertain. J. Leukoc. Biol. 65: 2–5; 1999.
The cell biology of leukocyte-mediated proteolysis
Authors: Owen Caroline A , Campbell Edward J
Published: January 2018

Leukocyte-derived proteinases have the capacity to degrade every component of the extracellular matrix, and thereby play fundamental roles in physiological processes. However, if the activity of these proteinases is uncontrolled or dysregulated, they have the capacity to contribute to tissue injury that potentially affects every organ in the body. Although there is a substantial literature on structure and activity of these proteinases when they are free in solution, until recently there has been little information about the cell biology of proteinases and their inhibitors. Recent studies, however, have identified several mechanisms by which inflammatory cells can degrade extracellular proteins in a milieu that contains high-affinity proteinase inhibitors. J. Leukoc. Biol. 65: 137–150; 1999.
Selective antibody blockade of lymphocyte migration to mucosal sites and mast cell adhesion
Authors: Palecanda Aiyappa , Marshall Jean S , Li Xian , Briskin Michael J , Issekutz Thomas B
Published: January 2018

The integrins α4β7 and α4β1 mediate adhesion to the mucosal addressin cell adhesion molecule-1 (MAdCAM-1) and the vascular cell adhesion molecule-1 (VCAM-1) and are important in T cell and allergic inflammatory reactions in the rat. The relative contributions of α4β7 and α4β1 in these reactions is unknown. To examine the role of α4β7 in the rat a new mAb, TA-6, was developed. TA-6 inhibited adhesion to MAdCAM-1 but not to VCAM-1, a characteristic of α4β7 adhesion, and immunofluorescence and immunoprecipitation studies were compatible with binding to α4β7. TA-6 blocked rat lymphocyte adhesion to mesenteric lymph nodes and T cell migration to mucosal lymphoid tissues and it bound to rat mucosal mast cells. TA-6 did not inhibit lymphocyte adhesion to peripheral lymph nodes and T cell migration to peripheral lymphoid tissues or cutaneous inflammatory sites, and was not expressed on connective tissue mast cells. J. Leukoc. Biol. 65: 649–657; 1999.
MCP-1 is selectively expressed in the late phase by cytokine-stimulated human neutrophils: TNF-α plays a role in maximal MCP-1 mRNA expression
Authors: Yamashiro Shigeo , Kamohara Hidenobu , Yoshimura Teizo
Published: January 2018

Culture supernatants of phytohemagglutinin (PHA)-stimulated human peripheral blood mononuclear cells (PHA-sup) induced monocyte chemoattractant protein-1 (MCP-1) mRNA expression in human neutrophils. MCP-1 mRNA was first detected by Northern analysis at 8 h, and the peak level was detected at 16 h and sustained until 72 h. Cycloheximide and genistein, but not pertussis toxin, inhibited the expression of MCP-1 mRNA. Recombinant tumor necrosis factor α (TNF-α) induced a low level MCP-1 mRNA accumulation in neutrophils, and addition of anti-TNF-α IgG blocked 30–70% of MCP-1 mRNA expression induced with PHA-sup. PHA-sup-stimulated PMN synthesized and secreted 3.1 ± 1.3 ng/5 × 106 PMN MCP-1 within the first 24 h. Hybridization of 32P-labeled cDNA preparations to an array of human cytokine cDNAs further indicated that MCP-1 mRNA was selectively up-regulated in the late phase after stimulation with the PHA-sup. J. Leukoc. Biol. 65: 671–679; 1999.
Exposure of cultured murine peritoneal macrophages to low concentrations of beryllium induces increases in intracellular calcium concentrations and stimulates DNA synthesis
Authors: Misra Uma K , Gawdi G , Pizzo Salvatore V , Lewis James G
Published: January 2018

Exposure of humans to beryllium dusts can induce a specific form of chronic pneumonitis that consists mainly of noncaseating granulomas in the lungs. Multiple studies have documented both genetic and immune components of chronic berylliosis. Much work has focused on T cells and their reactivity in berylliosis, but less work has focused on the end effector cells in granulomatous inflammation, macrophages. Because macrophages must become activated to form granulomas, and they become activated by responding to numerous immunomodulatory signals, we investigated the effects of beryllium (BeCl2) on a central signal transduction pathway in macrophages, increases in intracellular calcium ([Ca2+]i). Exposure of cultured murine peritoneal macrophages to low, non-toxic concentrations induced successive spikes or oscillations in [Ca2+]i. Concentrations as low as 5 nM induced significant increases in [Ca2+]i. The source of the increased [Ca2+]i was exclusively extracellular in that increases in [Ca2+]i could be completely blocked by chelating extracellular Ca2+, were inhibited by the Ca2+ channel blocker verapamil, and exposure of macrophages to BeCl2 had no effect on IP3 concentrations. DNA synthesis, a Ca2+-sensitive function, was enhanced in dividing 1LN cells and induced de novo in quiescent macrophages. Furthermore, BeCl2 enhanced DNA synthesis in the absence of coexposure to the protein kinase C activator phorbol myristate acetate. These data support the hypothesis that beryllium toxicity is in part the result of altered Ca2+ metabolism in mononuclear phagocytes consequent to reversible opening of plasma membrane channels. J. Leukoc. Biol. 65: 786–791; 1999.
Aspirin-induced increases in soluble IL-1 receptor type II concentrations in vitro and in vivo
Authors: Daun Jane M , Ball Richard W , Burger Heather R , Cannon Joseph G
Published: January 2018

This study examined the influence of low-dose aspirin on interleukin (IL)-1β, IL-1 receptor antagonist (IL-1ra), and soluble receptor type II (sIL-1RII) secretion in vivo and in vitro. Blood mononuclear cells were isolated from healthy young men who ingested 81 mg of aspirin on alternate days for 2 weeks and from unmedicated controls. Aspirin had minor effects on ex vivo secretion of IL-1β and no influence on IL-1ra. In contrast, unstimulated ex vivo secretion of sIL-1RII was over twice as high by cells from aspirin-treated subjects (1115 ± 123 vs. 460 ± 77 pg/mL, P = 0.02). Lipopolysaccharide-stimulated sIL-1RII secretion was influenced similarly. Plasma sIL-1RII concentrations were 23% higher in aspirin-treated subjects (10.2 ± 0.6 vs. 8.4 ± 0.3 ng/mL, P = 0.03). In addition, cells from unmedicated subjects cultured in vitro with aspirin (10 μg/mL) secreted significantly greater amounts of sIL-1RII. Thus, low-dose aspirin therapy may prevent inflammation by increasing soluble receptor secretion, thereby preventing IL-1 from binding target cells. J. Leukoc. Biol. 65: 863–866; 1999.
Inhibitors of PI 3-kinase and MEK kinase differentially affect mediator secretion from immunologically activated human basophils
Authors: Gibbs Bernhard F , Grabbe Jurgen
Published: January 2018

Effects of inhibitors of PI 3-kinase and MEK kinases were investigated on histamine, leukotriene C4 (LTC4), and cytokine release from human basophils stimulated with anti-IgE. The PI 3-kinase antagonists wortmannin (> 10 nM) and LY 294002 (> 1 μM) strongly inhibited anti-IgE-induced release of all mediators by 40–100%. This was contrasted by the effects of the MEK kinase inhibitor PD 098059, which weakly inhibited histamine, interleukin (IL)-4, and IL-13 release but was substantially more efficacious at blocking LTC4 production (> 70% at 10 μM). Previous studies have shown that arachidonic acid synthesis is controlled by MEK kinases. We observed that wortmannin, LY 294002, and PD 098059 reduce basophil ERK-1,2 activation, thus implying that, with regard to arachidonic acid metabolism, MEK kinases are a downstream target for PI-3-kinase. Our results demonstrate a universal regulatory role played by PI 3-kinases in basophil mediator production and release, whereas MEK kinase signaling is largely limited to controlling arachidonic acid metabolism. J. Leukoc. Biol. 65: 883–890; 1999.