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1.
Pharmacogenomics J ; 6(2): 141-52, 2006.
Article in English | MEDLINE | ID: mdl-16402082

ABSTRACT

Accumulating evidence in animal models and human asthma support a central role for IL-13 signaling in disease pathogenesis. In order to identify asthma and therapy associated genes, global transcriptional changes were monitored in mouse lung following antigen challenge (ovalbumin (OVA)), either alone or in the presence of a soluble IL-13 antagonist. Changes in whole lung gene expression after instillation of mIL-13 were also measured both in wild type and STAT6 deficient mice. A striking overlap in the gene expression profiles induced by either OVA challenge or mIL-13 was observed, further strengthening the relationship of IL-13 signaling to asthma. Consistent with results from functional studies, a subset of the OVA-induced gene expression was significantly inhibited by a soluble IL-13 antagonist while IL-13-modulated gene expression was completely attenuated in the absence of STAT6-mediated signaling. Results from these experiments greatly expand our understanding of asthma and provide novel molecular targets for therapy and potential biomarkers of IL-13 antagonism.


Subject(s)
Asthma/genetics , Gene Expression , Lung/drug effects , Animals , Antigens/immunology , Antigens/pharmacology , Asthma/drug therapy , Asthma/immunology , Disease Models, Animal , Gene Expression/drug effects , Gene Expression/immunology , Gene Expression Profiling , Interleukin-13/antagonists & inhibitors , Interleukin-13/immunology , Interleukin-13/pharmacology , Lung/immunology , Lung/metabolism , Mice , Mice, Inbred BALB C , Mice, Knockout , Oligonucleotide Array Sequence Analysis , Ovalbumin/immunology , Ovalbumin/pharmacology , STAT6 Transcription Factor/genetics
2.
Shock ; 15(4): 285-90, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11303727

ABSTRACT

P-selectin is a major component in the early interaction between platelets, endothelial cells, and inflammatory cells in the initial phases of the innate immune response. The major ligand for P-selectin is P-selectin glycoprotein ligand-1 (PSGL-1) and this ligand is expressed on the surface of monocyte, lymphocyte, and neutrophil membranes. A truncated form of recombinant human P-selectin glycoprotein ligand-1 has been covalently linked to immunoglobulin G (rPSGL-Ig) and this fusion peptide functions as a competitive inhibitor of PSGL-1. As an inhibitor of neutrophil-endothelial cell adherence, rPSGL-Ig is in early clinical development for the treatment of ischemia reperfusion injury. To determine the potential for deleterious effects from inhibition in P-selectin-mediated neutrophil attachment in the presence of bacterial infection, the effects of therapeutic doses of rPSGL-Ig were tested in three standard laboratory sepsis models. The experimental models included: the murine systemic Listeria monocytogenes infection model, the Pseudomonas aeruginosa bacteremia model in neutropenic rats, and the cecal ligation and puncture (CLP)-induced peritonitis model in rats. Recombinant human PSGL-Ig had no adverse effects on mortality or immune clearance in systemic bacterial infection in any of the three infection models. The PSGL-1 inhibitor did significantly decrease local neutrophil infiltration and bacterial clearance in the peritoneum following CLP, but this did not increase the systemic levels of proinflammatory cytokines, the quantitative levels of bacteremia, or the overall mortality rate following CLP. The results indicate that rPSGL-Ig did not exacerbate infection in these experimental sepsis models.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Bacterial Infections/drug therapy , Chemotaxis, Leukocyte/drug effects , Immunoconjugates/therapeutic use , Membrane Glycoproteins/antagonists & inhibitors , Membrane Glycoproteins/therapeutic use , Animals , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Anti-Inflammatory Agents, Non-Steroidal/toxicity , Bacteremia/blood , Bacteremia/drug therapy , Bacteremia/immunology , Bacteremia/microbiology , Bacterial Infections/immunology , Cecum/injuries , Cell Adhesion/drug effects , Cytokines/blood , Depression, Chemical , Drug Evaluation, Preclinical , Female , Genes, Immunoglobulin , Humans , Immunoconjugates/pharmacology , Immunoconjugates/toxicity , Immunoglobulin Fc Fragments , Immunoglobulin G/genetics , Intestinal Perforation/complications , Listeriosis/drug therapy , Listeriosis/immunology , Membrane Glycoproteins/pharmacology , Membrane Glycoproteins/toxicity , Mice , Mice, Inbred C57BL , Neutropenia/chemically induced , Neutropenia/complications , Neutrophils/drug effects , Neutrophils/physiology , P-Selectin/physiology , Peritonitis/drug therapy , Peritonitis/immunology , Pseudomonas Infections/blood , Pseudomonas Infections/drug therapy , Pseudomonas Infections/immunology , Rats , Rats, Sprague-Dawley , Recombinant Fusion Proteins/pharmacology , Recombinant Fusion Proteins/therapeutic use , Recombinant Fusion Proteins/toxicity , Safety , Specific Pathogen-Free Organisms
3.
Parasite Immunol ; 23(2): 71-84, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11240898

ABSTRACT

Changes in gene expression and cellular distribution in the lymph node and at the site of infection, the footpad, during Leishmania major infection and/or IL-12 administration were evaluated. Otherwise susceptible BALB/c mice given IL-12 are able to resolve infection. Interestingly, iNOS was not induced in the lymph node by IL-12, yet, nitric oxide is critical in the control of leishmaniasis. However, we observed an increase in iNOS at the lesion site in response to IL-12. These results reflect the importance of examining the primary site of infection. We observed no changes in inflammation at the lesion site; however, IL-12 promoted an early inflammatory response in the lymph nodes. IL-12 administration differentially affected both the local and systemic immune response to invading leishmanial parasites. IL-12 induced iNOS at the lesion site and an early granulomatous inflammation in the lymph node; therefore, we hypothesize that these are key events responsible for the resolution of disease in BALB/c mice treated with IL-12.


Subject(s)
Interleukin-12/administration & dosage , Leishmania major , Leishmaniasis, Cutaneous/drug therapy , Lymph Nodes/immunology , Animals , Cytokines/analysis , Cytokines/genetics , Disease Models, Animal , Female , Foot , Histocytochemistry , Interleukins/genetics , Interleukins/isolation & purification , Leishmania major/immunology , Leishmania major/isolation & purification , Leishmaniasis, Cutaneous/immunology , Leishmaniasis, Cutaneous/parasitology , Lymph Nodes/metabolism , Lymph Nodes/pathology , Mice , Mice, Inbred BALB C , Nitric Oxide Synthase/analysis , Nitric Oxide Synthase/biosynthesis , Polymerase Chain Reaction/methods , RNA/genetics , RNA, Messenger/analysis , Staining and Labeling
4.
Am J Physiol Lung Cell Mol Physiol ; 280(4): L813-21, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11238023

ABSTRACT

Lymphocyte and/or eosinophil recruitment is dependent on the sequential interactions between adhesion molecules expressed on activated endothelial cells and both leukocyte subtypes. Endothelial P- and E-selectins mediate tethering and rolling of leukocytes through interactions with P-selectin glycoprotein ligand-1 (PSGL-1), and diapedesis subsequently occurs by engagement of endothelial vascular cell adhesion molecule-1 and CD49d (alpha(4)-integrins). The anti-inflammatory potential of interfering with these adhesive interactions was assessed with an ovalbumin challenge mouse model of asthma. Administration of a soluble form of PSGL-1 reduced eosinophils (80%) and lymphocytes (50%) in bronchoalveolar lavage fluid without affecting epithelial changes or airway hyperreactivity (AHR). In contrast, although administration of anti-CD49d monoclonal antibodies (PS/2) resulted in similar reductions in eosinophils (75%) and lymphocytes (50%), PS/2 reduced and abolished mucous cell metaplasia and AHR, respectively. Administration of both PSGL-1 and PS/2 had the additive effect of eliminating eosinophils from the airways (96% decrease), with few or no additional reductions (relative to PS/2 administration alone) in lymphocyte recruitment, mucous cell metaplasia, or AHR. These data show that eosinophils and lymphocytes differentially utilize adhesive interactions during recruitment and that the inhibition of AHR is independent of this recruitment.


Subject(s)
Antigens, CD/physiology , Hypersensitivity/complications , Leukocytes/drug effects , Leukocytes/physiology , Pneumonia/prevention & control , Animals , Antibodies, Monoclonal/pharmacology , Antigens, CD/drug effects , Antigens, CD/immunology , Blood Cells/pathology , Bronchial Hyperreactivity/prevention & control , Drug Combinations , Eosinophilia/pathology , Female , Integrin alpha4 , Lung/pathology , Membrane Glycoproteins/pharmacology , Mice , Mice, Inbred BALB C , Pneumonia/etiology , Pneumonia/pathology , Recombinant Proteins , Respiratory Mucosa/drug effects , Respiratory Mucosa/pathology , Solubility
5.
Invest Ophthalmol Vis Sci ; 41(12): 3856-61, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11053286

ABSTRACT

PURPOSE: A murine model of helminth-induced keratitis (river blindness) that is characterized by a biphasic recruitment of neutrophils (days 1-3) and eosinophils (days 3+) to the cornea has been developed. The purpose of this study was to determine the relative contribution of P- and E-selectin in recruitment of these inflammatory cells from limbal vessels to the corneal stroma. METHODS: P- and E-selectin gene knockout (-/-) mice were immunized with antigens extracted from the parasitic helminth Onchocerca volvulus. One week after the last immunization, parasite antigens were injected directly into the corneal stroma. Mice were killed on days 1 and 3 postchallenge, and eyes were immunostained with either anti-eosinophil major basic protein (MBP) or with anti-neutrophil Ab. The number of cells in the cornea was determined by direct counting. RESULTS: Recruitment of eosinophils to the cornea was significantly impaired in P-selectin(-/-) mice (63.9% fewer eosinophils on day 1 [P: = 0.0015], and 61% fewer on day 3 [P: < 0.0001]) compared with control C57BL/6 mice. In contrast, P-selectin deficiency had no effect on neutrophil recruitment to the cornea. There was no inhibition of eosinophil and neutrophil migration to the corneas of E-selectin(-/-) mice, indicating that there is no direct role for this adhesion molecule in helminth-induced keratitis. CONCLUSIONS: The present study demonstrates that P-selectin is an important mediator of eosinophil recruitment to the cornea. P-selectin interactions may therefore be potential targets for immunotherapy in eosinophil-mediated ocular inflammation.


Subject(s)
Chemotaxis, Leukocyte/immunology , Cornea/immunology , Eosinophils/immunology , Keratitis/immunology , Onchocerca volvulus/immunology , Onchocerciasis, Ocular/immunology , P-Selectin/physiology , Ribonucleases , Animals , Antigens, Helminth/immunology , Blood Proteins/immunology , Cornea/parasitology , Cornea/pathology , Disease Models, Animal , E-Selectin/genetics , E-Selectin/physiology , Enzyme-Linked Immunosorbent Assay , Eosinophil Granule Proteins , Fluorescent Antibody Technique, Indirect , Immunization , Immunoenzyme Techniques , Immunoglobulin E/analysis , Interleukin-5/metabolism , Keratitis/parasitology , Keratitis/pathology , Mice , Mice, Inbred C57BL , Mice, Knockout , Neutrophils/immunology , Onchocerciasis, Ocular/parasitology , Onchocerciasis, Ocular/pathology , P-Selectin/genetics , Spleen/cytology , Spleen/metabolism
6.
J Infect Dis ; 182(5): 1497-502, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11023473

ABSTRACT

In experimental visceral leishmaniasis, interleukin (IL)-12 initiates control over Leishmania donovani via Th1 cell activation, interferon (IFN)-gamma secretion, and granuloma formation. Because the leishmanicidal effect of conventional therapy, pentavalent antimony (Sb), also requires T cells and endogenous IFN-gamma, we tested IL-12 as a determinant of host responsiveness to chemotherapy. L. donovani-challenged IL-12p35 gene knockout (KO) mice permitted uncontrolled hepatic infection and failed to respond to Sb. In contrast, 96% of liver parasites in KO mice were killed by amphotericin B, which acts independently of immune responses. Exogenous IL-12 combined with Sb was tested in normal mice: low-dose Sb was converted from weakly to strongly leishmanicidal, and a no-effect Sb dose was converted to approximately 100% leishmanistatic. IL-12 plus Sb synergism in normal mice was IFN-gamma dependent; however, IL-12 also increased responsiveness to Sb in IFN-gamma KO mice. Thus, IL-12 regulates host IFN-gamma-dependent and -independent responses that permit and/or enhance the leishmanicidal activity of Sb.


Subject(s)
Interleukin-12/physiology , Leishmaniasis, Visceral/drug therapy , Animals , Antimony/therapeutic use , Interferon-gamma/physiology , Interleukin-4/physiology , Mice , Mice, Inbred BALB C , Mice, Knockout
7.
Eur J Immunol ; 30(7): 2083-91, 2000 Jul.
Article in English | MEDLINE | ID: mdl-10940898

ABSTRACT

Female IL-4 knockout (KO) mice on a C57BL/6 background (F4KOC57) are susceptible to infection with the cecal-dwelling nematode Trichuris muris whereas wild-type C57BL/6 mice are resistant and expel the parasite. In this study we show that in sharp contrast, female IL-4 KO mice on a BALB/c background (F4KOB/c) are resistant to infection as are wild-type BALB/c mice. Although susceptible F4KOC57 make negligible levels of all type 2 cytokines, resistant F4KOB/c were capable of producing significant levels of antigen-specific IL-13 (a cytokine shown to be critical in resistance to T. muris). To examine if the IL-13 in F4KOB/c mice was of functional importance, it was neutralized in vivo using a fusion protein, A25 (sIL-13 R.Fc). The results presented here clearly demonstrate that neutralization of IL-13 in vivo did indeed prevent T. muris expulsion in normally resistant F4KOB/c mice. In addition, administration of recombinant mouse IL-13 to normally susceptible male IL-4KO BALB/c mice (M4KOB/c) caused an 87.85 % reduction in worm burden. Collectively, these data show that IL-13 is important in the poorly understood effector mechanisms resulting in the expulsion of T. muris from the gut. Moreover, the present data highlight the functional importance of gender and background strain in interpretation of studies using gene-targeted animals.


Subject(s)
Interleukin-13/immunology , Interleukin-4/immunology , Intestinal Diseases, Parasitic/immunology , Trichuriasis/immunology , Animals , Antibodies, Helminth/blood , Disease Susceptibility , Female , Humans , Immunity, Innate , Immunoglobulin G/blood , Interferon-gamma/blood , Interleukin-13/biosynthesis , Interleukin-4/biosynthesis , Interleukin-4/genetics , Interleukin-5/biosynthesis , Interleukin-9/biosynthesis , Intestinal Diseases, Parasitic/parasitology , Male , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, Knockout , Neutralization Tests , Trichuriasis/parasitology , Trichuris/immunology
8.
J Immunol ; 163(10): 5257-64, 1999 Nov 15.
Article in English | MEDLINE | ID: mdl-10553047

ABSTRACT

The biological response to IL-12 is mediated through specific binding to a high affinity receptor complex composed of at least two subunits (designated IL-12Rbeta1 and IL-12Rbeta2) that are expressed on NK cells and activated T cells. The selective loss of IL-12Rbeta2 expression during Th2 T cell differentiation suggests that regulation of this receptor component may govern IL-12 responsiveness. In murine assays, down-regulation of IL-12Rbeta2 expression can be prevented by treatment with IFN-gamma, indicating that receptor expression and hence IL-12 responsiveness may be regulated, at least in part, by the local cytokine milieu. In this study, we report that cellular expression of both IL-12Rbeta1 and beta2 mRNA is increased in the lymph nodes of naive mice following systemic administration of murine rIL-12 (rmIL-12). Changes in IL-12R mRNA were associated with increased IFN-gamma secretion following ex vivo activation of lymph node cells with rmIL-12, indicating the presence of a functional receptor complex. Expression of IL-12R mRNA was not restricted to lymph node T cells, and its autocrine regulation was independent of secondary IFN-gamma secretion. Data from fractionated lymph node cells as well as rmIL-12-treated B cell-deficient mice suggest that IL-12-responsive B cells may represent an alternative cellular source for IFN-gamma production. However, the strength of the biological response to rmIL-12 is not governed solely by receptor expression, as rmIL-12-induced IFN-gamma secretion from cultured lymph node cells is accessory cell dependent and can be partially blocked by inhibition of B7 costimulation.


Subject(s)
Autocrine Communication/immunology , Interferon-gamma/metabolism , Interleukin-12/metabolism , Killer Cells, Natural/immunology , Receptors, Interleukin/biosynthesis , T-Lymphocytes/immunology , Animals , Antibodies, Blocking/pharmacology , Antigen-Presenting Cells/immunology , B7-1 Antigen/immunology , Female , Injections, Subcutaneous , Interferon-gamma/deficiency , Interferon-gamma/genetics , Interleukin-12/administration & dosage , Interleukin-12/genetics , Killer Cells, Natural/metabolism , Lymph Nodes/cytology , Lymph Nodes/immunology , Lymph Nodes/metabolism , Mice , Mice, Inbred C3H , Mice, Inbred C57BL , Mice, Knockout , Receptors, Interleukin/genetics , Receptors, Interleukin-12 , Recombinant Proteins/administration & dosage , T-Lymphocytes/metabolism
9.
Eur J Immunol ; 29(11): 3621-8, 1999 11.
Article in English | MEDLINE | ID: mdl-10556817

ABSTRACT

In this study we characterized Th2 responses in the absence of IL-4. We show that ST2L, a stable Th2 marker, is expressed at similar levels in Leishmania major-infected IL-4-deficient (IL-4(-/-)) and wild-type BALB/c (IL-4(+/+)) mice. Th2 cytokines are secreted by in vivo differentiated lymphocytes in response to specific activation in the absence of IL-4. Although IL-13 is produced, its neutralization did not alter the outcome of infection. Thus, we demonstrate that Th2 differentiation as assessed by the expression of ST2L and the production of Th2 cytokines can occur in vivo in the absence of IL-4.


Subject(s)
Cytokines/biosynthesis , Interleukin-4/immunology , Leishmania major/immunology , Leishmaniasis, Cutaneous/immunology , Membrane Proteins , Protein Biosynthesis , Th2 Cells/immunology , Animals , Antibodies, Monoclonal , Cricetinae , Disease Models, Animal , Interleukin-1 Receptor-Like 1 Protein , Interleukin-10/biosynthesis , Interleukin-13/biosynthesis , Interleukin-5/biosynthesis , Interleukin-6/biosynthesis , Mice , Mice, Inbred BALB C , Mice, Knockout , Neutralization Tests , Receptors, Interleukin
10.
J Immunol ; 163(8): 4481-8, 1999 Oct 15.
Article in English | MEDLINE | ID: mdl-10510390

ABSTRACT

Protection from cutaneous leishmaniasis, a chronic ulcerating skin lesion affecting millions, has been achieved historically using live virulent preparations of the parasite. Killed or recombinant Ags that could be safer as vaccines generally require an adjuvant for induction of a strong Th1 response in murine models. Murine rIL-12 as an adjuvant with soluble Leishmania Ag has been shown to protect susceptible mice. We used 48 rhesus macaques to assess the safety, immunogenicity, and efficacy of a vaccine combining heat-killed Leishmania amazonensis with human rIL-12 (rhIL-12) and alum (aluminum hydroxide gel) as adjuvants. The single s.c. vaccination was found to be safe and immunogenic, although a small transient s.c. nodule developed at the site. Groups receiving rhIL-12 had an augmented in vitro Ag-specific IFN-gamma response after vaccination, as well as increased production of IgG. No increase in IL-4 or IL-10 was found in cell culture supernatants from either control or experimental groups. Delayed hypersensitivity reactions were not predictive of protection. Intradermal forehead challenge infection with 107 metacyclic L. amazonensis promastigotes at 4 wk demonstrated protective immunity in all 12 monkeys receiving 2 microgram rhIL-12 with alum and Ag. Partial efficacy was seen with lower doses of rhIL-12 and in groups lacking either adjuvant. Thus, a single dose vaccine with killed Ag using rhIL-12 and alum as adjuvants was safe and fully effective in this primate model of cutaneous leishmaniasis. This study extends the murine data to primates, and provides a basis for further human trials.


Subject(s)
Adjuvants, Immunologic/administration & dosage , Alum Compounds/administration & dosage , Interleukin-12/immunology , Leishmaniasis, Cutaneous/immunology , Leishmaniasis, Cutaneous/prevention & control , Protozoan Vaccines/immunology , Vaccines, Synthetic/immunology , Animals , Disease Models, Animal , Dose-Response Relationship, Immunologic , Humans , Immunity, Active/genetics , Interferon-gamma/metabolism , Interleukin-12/genetics , Macaca mulatta , Protozoan Vaccines/adverse effects , Protozoan Vaccines/genetics , Vaccines, Synthetic/adverse effects
11.
Infect Immun ; 67(5): 2166-71, 1999 May.
Article in English | MEDLINE | ID: mdl-10225870

ABSTRACT

Previously we demonstrated that recombinant murine interleukin-12 (rmIL-12) administration can promote a primary Th1 response while suppressing the Th2 response in mice primed with 2,4, 6-trinitrophenyl-keyhole limpet hemocyanin (TNP-KLH). The present studies examined the capacity of rmIL-12 to drive a Th1 response to TNP-KLH in the presence of an ongoing Th2-mediated disease. To establish a distinct Th2 response, we used a murine model of leishmaniasis. Susceptible BALB/c mice produce a strong Th2 response when infected with Leishmania major and develop progressive visceral disease. On day 26 postinfection, when leishmaniasis was well established, groups of mice were immunized with TNP-KLH in the presence or absence of exogenous rmIL-12. Even in the presence of overt infection, TNP-KLH-plus-rmIL-12-immunized mice were still capable of generating KLH-specific gamma interferon (IFN-gamma) as well as corresponding TNP-specific immunoglobulin G2a (IgG2a) titers. In addition, the KLH-specific IL-4 was suppressed in infected mice immunized with rmIL-12. However, parasite-specific IL-4 and IgG1 production with a lack of parasite-specific IFN-gamma secretion were maintained in all infected groups of mice including those immunized with rmIL-12. These data show that despite the ongoing infection-driven Th2 response, rmIL-12 was capable of generating an antigen-specific Th1 response to an independent immunogen. Moreover, rmIL-12 administered with TNP-KLH late in infection did not alter the parasite-specific cytokine or antibody responses.


Subject(s)
Interleukin-12/pharmacology , Th1 Cells/immunology , Th2 Cells/immunology , Animals , Cytokines/biosynthesis , Female , Haptens , Hemocyanins/immunology , Immunoglobulin G/blood , Interferon-gamma/biosynthesis , Interleukin-4/biosynthesis , Leishmania major , Leishmaniasis, Cutaneous/immunology , Mice , Mice, Inbred BALB C , Recombinant Proteins/pharmacology
12.
J Immunol ; 160(1): 284-92, 1998 Jan 01.
Article in English | MEDLINE | ID: mdl-9551982

ABSTRACT

Studies on murine candidiasis suggest that resistance to disease is linked to a Th1 response and production of IFN-gamma, while failure to elicit protection is associated with a Th2 response and production of IL-4 and IL-10. Experimental infection of C57BL/6 mice, IL-12 treatment of these mice, or both infection and IL-12 treatment resulted in a characteristic Th1 cytokine mRNA profile as measured by quantitative competitive PCR. Specifically, little or no IL-4 transcripts were detected, while IFN-gamma message was elevated, particularly with IL-12 treatment. Despite its role in driving increased IFN-gamma expression and production, IL-12 treatment, paradoxically, promoted disease progression in our model. Therefore, we examined the effect of IFN-gamma neutralization on IL-12-induced susceptibility to infection. None of the systemically infected mice receiving IL-12 alone survived, while IL-12- and anti-IFN-gamma-treated mice had a 70% survival rate, similar to that after infection alone. These results suggested that IFN-gamma induced by IL-12 treatment contributed to lethality. However, in separate studies, IFN-gamma knockout mice were more susceptible to infection than their wild-type counterparts, suggesting that IFN-gamma is required for resistance. Nonetheless, infected IFN-gamma knockout mice treated with recombinant murine IL-12 exhibited enhanced resistance, suggesting that the toxicities observed with IL-12 are directly attributable to IFN-gamma and that an optimal immune response to Candida infections necessitates a finely tuned balance of IFN-gamma production. Thus, we propose that although IFN-gamma can drive resistance, the overproduction of IFN-gamma during candidiasis, mediated by IL-12 administration, leads to enhanced susceptibility.


Subject(s)
Candidiasis/immunology , Immunity, Cellular , Interferon-gamma/pharmacology , Interleukin-12/physiology , Animals , Candida albicans , DNA, Complementary/genetics , Female , Interleukin-10/metabolism , Interleukin-12/pharmacology , Interleukin-4/metabolism , Kidney/immunology , Mice , Mice, Inbred C57BL , Mice, Knockout , Recombinant Proteins , Spleen/immunology , Survival Analysis
13.
AIDS Res Hum Retroviruses ; 14(5): 393-9, 1998 Mar 20.
Article in English | MEDLINE | ID: mdl-9546798

ABSTRACT

With the demonstration that interleukin 12 can enhance natural killer (NK) cell activity and drive CD4+ lymphocytes toward T helper type 1 (Thl) responses, there is a strong rationale for exploring the use of this cytokine as an immunomodulatory therapy in HIV-1-infected individuals. To assess its potential safety and effects on both immune and virologic aspects of HIV-1 infection, recombinant human IL-12 (rhIL-12) was assessed in rhesus monkeys chronically infected with the simian immunodeficiency virus of macaques (SIVmac). The activity of rhIL-12 on rhesus monkey lymphocytes was confirmed with the demonstration that peripheral blood lymphocyte lysis of the NK-sensitive cell line Colo was enhanced by this recombinant cytokine. Further, rhIL-12 was shown to induce interferon-gamma production by rhesus monkey lymphocytes in vitro. Then, in separate studies, two treatment regimens of rhIL-12 were assessed in SIVmac-infected monkeys: a low-dose regimen (0.1 microg/kg, daily for 4 weeks) and a high-dose regimen (2.5 microg/kg, every 3-4 days, for 3 weeks). Both rhIL-12 treatment regimens were well tolerated by these virus-infected animals. The high-dose regimen of rhIL-12 induced transient decreases in circulating lymphocytes in the SIVmac-infected monkeys. Furthermore, no changes in lymphocyte-associated SIVmac DNA or SIVmac plasma RNA levels were seen in the treated monkeys. These studies indicate that short-term treatment with rhIL-12 is well tolerated and causes no measurable changes in virus load in chronically SIVmac-infected rhesus monkeys.


Subject(s)
Antiviral Agents/therapeutic use , Interleukin-12/therapeutic use , Simian Acquired Immunodeficiency Syndrome/drug therapy , Simian Immunodeficiency Virus/drug effects , Animals , Chronic Disease , Enzyme-Linked Immunosorbent Assay , Humans , Immunophenotyping , Interferon-gamma/biosynthesis , Killer Cells, Lymphokine-Activated/immunology , Lymphocytes/drug effects , Lymphocytes/metabolism , Lymphocytes/virology , Macaca mulatta , RNA, Viral/isolation & purification , Recombinant Proteins/therapeutic use , Simian Acquired Immunodeficiency Syndrome/immunology , Simian Acquired Immunodeficiency Syndrome/virology , Viral Load
14.
J Immunol ; 159(7): 3434-43, 1997 Oct 01.
Article in English | MEDLINE | ID: mdl-9317142

ABSTRACT

IL-4 drives polarized Th2 responses, and differentiating Th2 cells down-regulate their sensitivity to IL-12. Therefore, the failure of BALB/c mice to heal Leishmania major infection could be due to an IL-4-dependent biased Th2 response or to a reduced capacity of Leishmania-specific Th cells to respond to IL-12. We examined the ability of CD4+ Th cells from L. major-infected wild-type and IL-4-deficient BALB/c mice to respond to IL-12. We show that the inability of normal and IL-4-deficient BALB/c mice to heal L. major infections is due to their inability to generate effective Th1 responses and not to persistent IL-4-dominated Th2 responses. Redirection of immune responses in vivo by administration of IL-12 or anti-CD4 mAb treatment in the early phase of infection (+/-12 days) allows both normal and IL-4-deficient BALB/c mice to heal their lesions by allowing them to develop an efficient Th1 response regardless of the presence or the absence of IL-4. Finally, on a population level, Ag-specific Th cells from infected animals induced to heal display a strongly elevated response to IL-12.


Subject(s)
Interleukin-4/deficiency , Leishmania major/immunology , Leishmaniasis, Cutaneous/immunology , T-Lymphocyte Subsets/immunology , Adjuvants, Immunologic/administration & dosage , Animals , Antibodies, Monoclonal/administration & dosage , CD4 Antigens/immunology , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/metabolism , Cytokines/metabolism , Disease Susceptibility , Female , Immunophenotyping , Interleukin-12/pharmacology , Interleukin-12/therapeutic use , Interleukin-4/genetics , Leishmaniasis, Cutaneous/genetics , Leishmaniasis, Cutaneous/therapy , Male , Mice , Mice, Inbred BALB C , Mice, Knockout , T-Lymphocytes, Helper-Inducer/classification , T-Lymphocytes, Helper-Inducer/immunology
15.
Eur J Immunol ; 27(4): 866-70, 1997 Apr.
Article in English | MEDLINE | ID: mdl-9130637

ABSTRACT

Resistance and susceptibility to the intestinal parasite Trichuris muris has been shown to be due to a dominant T helper 2 (Th2) and a dominant Th1 response, respectively. The factors determining the initial polarization of the immune response remain largely unresolved, although the cytokine environment at the time of antigen presentation clearly plays an essential role. Interleukin (IL)-12, a cytokine produced mainly by macrophages, dendritic cells, and other monocytes has been shown to be important in driving a strong Th1 response by stimulating the production of interferon (IFN)-gamma from natural killer and Th0 cells and therefore forms a link between the innate and adaptive immune system. IL-12 has been shown to play an important role in resistance to a number of intracellular pathogens, including Listeria and Leishmania. It has also been proposed as an anti-tumor agent and for use in the treatment of HIV. Conversely, IL-12 has been shown to prolong the survival of Nippostrongylus brasiliensis and to accelerate autoimmunity. Our studies demonstrate that by driving a strong Th1 response, IL-12 promotes chronic T. muris infection when given to normally resistant BALB/K mice. Parasite-specific IgG2a, a Th1 parameter of infection, was greatly up-regulated, whereas some Th2 parameters of infection were down-regulated. IL-12 treatment could be delayed until 1 week after infection had started and still promote a strong Th1 response. The actions of IL-12 in promoting a chronic infection were IFN-gamma dependent as an anti-IFN-gamma mAb abrogated the effects of IL-12.


Subject(s)
Interleukin-12/physiology , Intestinal Diseases, Parasitic/etiology , Intestinal Diseases, Parasitic/immunology , Trichuriasis/etiology , Trichuriasis/immunology , Trichuris/immunology , Animals , Chronic Disease , Down-Regulation/immunology , Immunity, Innate/drug effects , Interferon-gamma/antagonists & inhibitors , Interleukin-12/antagonists & inhibitors , Intestinal Diseases, Parasitic/parasitology , Male , Mice , Mice, Inbred BALB C , Th1 Cells/immunology , Th2 Cells/immunology , Trichuriasis/parasitology , Up-Regulation/immunology
16.
Infect Immun ; 64(11): 4557-60, 1996 Nov.
Article in English | MEDLINE | ID: mdl-8890206

ABSTRACT

B-1 cells (CD5+ B220+) are a self-replenishing lineage of B cells which are autoreactive and capable of producing large amounts of interleukin-10 (IL-10). In mice experimentally infected with the human helminth parasite Schistosoma mansoni, expansion of B-1 cells is seen in the peritoneal cavity just prior to egg laying. In naive mice, B-1 cell expansion can be elicited by intraperitoneal injection of saline soluble egg antigens (SEA) or the polylactosamine sugar lacto-N-fucopentaose III (LNFPIII), which contains the Lewis-X trisaccharide. In this study, we demonstrate that LNFPIII is the major stimulus in SEA responsible for expansion of B-1 cells, since SEA-induced B-1 outgrowth is blocked by multiple injections of non-cross-linked free LNFPIII. IL-10 is an autocrine growth factor for B-1 cells, and we show that B-1 outgrowth after SEA and LNFPIII administration is inhibited by injection of anti-IL-10 antibodies. Furthermore, SEA- and LNFPIII-induced expansion of B-1 cells is inhibited by in vivo administration of recombinant murine IL-12 or recombinant gamma interferon. These data suggest that activation and expansion of IL-10-producing B-1 cells are governed via cross-regulatory cytokines.


Subject(s)
Antigens, Helminth/immunology , B-Lymphocytes/immunology , Cytokines/immunology , Oligosaccharides/immunology , Schistosoma mansoni/immunology , Animals , CD5 Antigens/analysis , Clone Cells , Interferon-gamma/immunology , Interferon-gamma/pharmacology , Interleukin-10/immunology , Interleukin-12/immunology , Leukocyte Common Antigens/analysis , Ligands , Male , Mice , Mice, Inbred CBA , Recombinant Proteins/pharmacology
18.
Anticancer Drugs ; 7(3): 275-80, 1996 May.
Article in English | MEDLINE | ID: mdl-8792000

ABSTRACT

Interleukin-12 (IL-12) has important immunomodulatory effects on T and natural killer (NK) cells that might be exploited in anticancer treatment. Murine IL-12 models have shown antimetastatic and antitumor effects against murine tumors in vivo. Data on the effects of human IL-12 on human tumors are confined to 51Cr-release assay studies showing that IL-12 increases NK activity against cancer cells. We used a human tumor cloning assay (HTCA) to investigate the effects of human IL-12 on solid tumors taken directly from patients. The HTCA is suitable to test direct, as well as immune-mediated, antitumor effects of cytokines on heterogeneous cell preparations derived from fresh tumors. Single cell suspensions prepared from 193 tumors were continuously exposed (14 days) to 10, 100 and 1000 ng/ml of human IL-12 in a capillary HTCA. Seventy-four (38%) specimens were evaluable. Inhibition of tumor growth was observed in 35 specimens (47%; concentration-related in 33 cases), including cancers of the ovary, lung, prostate, breast, colon and kidney, as well as melanoma. Antitumor effect was observed in 10 (14%), 18 (24%) and 32 (43%) tumors, at 10, 100 and 1000 ng/ml of IL-12, respectively. One specimen (1%), a melanoma, showed stimulation of tumor proliferation only at 100 mg/ml of IL-12. Our results show that IL-12 has substantial in vitro activity against a variety of solid tumors taken directly from patients. Clinical trials of IL-12 in patients with solid tumors are warranted.


Subject(s)
Interleukin-12/pharmacology , Colony-Forming Units Assay , Dose-Response Relationship, Drug , Humans , Recombinant Proteins/pharmacology , Tumor Cells, Cultured/drug effects
19.
J Immunol ; 155(5): 2515-24, 1995 Sep 01.
Article in English | MEDLINE | ID: mdl-7650381

ABSTRACT

IL-12, a cytokine produced by macrophages and B cells, has recently been found to exert pleiotropic effects on the immune system. When BALB/c mice, a strain highly susceptible to virulent Mycobacterium tuberculosis infection, were given IL-12 at the initiation of infection with M. tuberculosis, their mean survival time doubled from 58 to 112 days. IL-12-treated mice had diminished bacterial burdens, whereas treatment with exogenous IFN-gamma had no effect on survival or bacterial burden. IL-12 treatment also delayed lung pathology in BALB/c mice. In contrast with the findings in the BALB/c model, IL-12 did not increase survival of M. tuberculosis-infected gko mice, transgenic mice in which the IFN-gamma gene has been disrupted, indicating that IL-12 does not induce protection against tuberculosis in mice in the absence of IFN-gamma.


Subject(s)
Interleukin-12/pharmacology , Mice, Inbred BALB C/immunology , Tuberculosis/immunology , Animals , BCG Vaccine/therapeutic use , Female , Granuloma/pathology , Immunity, Innate , Interferon-gamma/pharmacology , Interferon-gamma/therapeutic use , Lymphokines/biosynthesis , Lymphokines/genetics , Major Histocompatibility Complex/physiology , Mice , Mice, Inbred C57BL , Mice, Inbred Strains , Mice, Mutant Strains , Mycobacterium tuberculosis/drug effects , Tuberculosis/prevention & control
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