Leishmania Amazonensis: Multiple Receptor-ligand Interactions Are Involved In Amastigote Infection Of Human Dendritic Cells

In their mammalian hosts, Leishmania are obligate intracellular parasites that reside in macrophages and dendritic cells (DCs). In the present study, we have investigated in vitro the mechanisms of entry into human DCs of Leishmania amazonensis amastigotes isolated from lesions in nude mice (Am nude). The DC infection rate with Am nude was approximately 36%, while opsonization of Am nude with normal human serum and infected human serum increased the DC infection rates to 60% and 62%, respectively. Heat inactivation and depletion of antibodies in sera brought the DC infection rate down to 40%. The DC infection rate was inhibited after pre-treatment of Am nude with heparin. We were unable to implicate mannose-fucose receptors in the uptake of Am nude by DCs. Our data suggest that the ability of L. amazonensis amastigotes to infect human DCs involves the participation of at least three multiple receptor-ligand interactions, antibodies/FcR, complement components/CR and proteoglycans/heparin-binding protein. © 2007 Elsevier Inc. All rights reserved.1163306310Arrais-Silva, W.W., Colhone, M.C., Ayres, D.C., Souto, P.C.S., Giorgio, S., Effects of hyperbaric oxygen on Leishmania amazonensis promastigotes and amastigotes (2005) Parasitology International, 54, pp. 1-7Avila, J.L., Rojas, M., Galili, U., Immunogenic Gal alpha 1-3Gal carbohydrate epitopes are present on pathogenic American Trypanosoma and Leishmania (1989) The Journal of Immunology, 142, pp. 2828-2834Barbieri, C.L., Giorgio, S., Merjan, A.J., Figueiredo, E.N., Glycosphingolipid antigens of Leishmania (Leishmania) amazonensis amastigotes identified by use of a monoclonal antibody (1993) Infection and Immunity, 61, pp. 2131-2137Blackwell, J.M., Ezekowitz, R.A., Roberts, M.B., Channon, J.Y., Sim, R.B., Gordon, S., Macrophage complement and lectin-like receptors bind Leishmania in the absence of serum (1985) The Journal of Experimental Medicine, 162, pp. 324-331Blank, C., Fuchs, H., Rappersberger, K., Rollinghoff, M., Moll, H., Parasitism of epidermal Langerhans cells in experimental cutaneous leishmaniasis with Leishmania major (1993) The Journal of Infectious Diseases, 167, pp. 418-425Brandonisio, O., Spinelli, R., Pepe, M., Dendritic cells in Leishmania infection (2004) Microbes and Infection, 6, pp. 1402-1409Butcher, B.A., Sklar, L.A., Seamer, L.C., Glew, R.H., Heparin enhances the interaction of infective Leishmania donovani promastigotes with mouse peritoneal macrophages. A fluorescence flow cytometric analysis (1992) The Journal of Immunology, 148, pp. 2879-2886Cantos, G., Barbieri, C.L., Iacomini, M., Gorin, P.A., Travassos, L.R., Synthesis of antimony complexes of yeast mannan and mannan derivatives and their effect on Leishmania-infected macrophages (1993) The Biochemical Journal, 289, pp. 155-160Chakraborty, P., Ghosh, D., Basu, M.K., Modulation of macrophage mannose receptor affects the uptake of virulent and avirulent Leishmania donovani promastigotes (2001) The Journal of Parasitology, 87, pp. 1023-1027Colmenares, M., Corbi, A.L., Turco, S.J., Rivas, L., The dendritic cell receptor DC-SIGN discriminates among species and life cycle forms of Leishmania (2004) The Journal of Immunology, 172, pp. 1186-1190Colmenares, M., Puig-Kroger, A., Pello, O.M., Corbi, A.L., Rivas, L., Dendritic cell (DC)-specific intercellular adhesion molecule 3 (ICAM-3)-grabbing nonintegrin (DC-SIGN, CD209), a C-type surface lectin in human DCs, is a receptor for Leishmania amastigotes (2002) The Journal of Biological Chemistry, 277, pp. 36766-36769Dominguez, M., Torano, A., Immune adherence-mediated opsonophagocytosis: the mechanism of Leishmania infection (1999) The Journal of Experimental Medicine, 189, pp. 25-35Grimaldi, G.R., Tesh, R.B., Leishmaniases of the New World: current concepts and implications for future research (1993) Clinical Microbiology Reviews, 6, pp. 230-250Guy, R.A., Belosevic, M., Comparison of receptors required for entry of Leishmania major amastigotes into macrophages (1993) Infection and Immunity, 61, pp. 1553-1558Handman, E., Cell biology of Leishmania (1999) Advances in Parasitology, 44, pp. 1-39Kima, P.E., Constant, S.L., Hannum, L., Colmenares, M., Lee, K.S., Haberman, A.M., Shlomchik, M.J., McMahon-Pratt, D., Internalization of Leishmania mexicana complex amastigotes via the Fc receptor is required to sustain infection in murine cutaneous leishmaniasis (2000) The Journal of Experimental Medicine, 191, pp. 1063-1067Kolb-Maurer, A., Pilgrim, S., Kampgen, E., McLellan, A.D., Brocker, E.B., Goebel, W., Gentschev, I., Antibodies against listerial protein 60 act as an opsonin for phagocytosis of Listeria monocytogenes by human dendritic cells (2001) Infection and Immunity, 69, pp. 3100-3109Laufs, H., Muller, K., Fleischer, J., Reiling, N., Jahnke, N., Jensenius, J.C., Solbach, W., Laskay, T., Intracellular survival of Leishmania major in neutrophil granulocytes after uptake in the absence of heat-labile serum factors (2002) Infection and Immunity, 70, pp. 826-835Love, D.C., Esko, J.D., Mosser, D.M., A heparin-binding activity on Leishmania amastigotes which mediates adhesion to cellular proteoglycans (1993) The Journal of Cell Biology, 123, pp. 759-766Mosser, D.M., Edelson, P.J., The mouse macrophage receptor for C3bi (CR3) is a major mechanism in the phagocytosis of Leishmania promastigotes (1985) The Journal of Immunology, 135, pp. 2785-2789Nair, S.K., Boczkowski, D., Morse, M., Cumming, R.I., Lyerly, H.K., Gilboa, E., Induction of primary carcinoembryonic antigen (CEA)-specific cytotoxic T lymphocytes in vitro using human dendritic cells transfected with RNA (1998) Nature Biotechnology, 16, pp. 364-369Navin, T.R., Krug, E.C., Pearson, R.D., Effect of immunoglobulin M from normal human serum on Leishmania donovani promastigote agglutination, complement-mediated killing, and phagocytosis by human monocytes (1989) Infection and Immunity, 57, pp. 1343-1346Peters, C., Aebischer, T., Stierhof, Y.D., Fuchs, M., Overath, P., The role of macrophage receptors in adhesion and uptake of Leishmania mexicana amastigotes (1995) Journal of Cell Science, 108, pp. 3715-3724Prina, E., Abdi, S.Z., Lebastard, M., Perret, E., Winter, N., Antoine, J.C., Dendritic cells as host cells for the promastigote and amastigote stages of Leishmania amazonensis: the role of opsonins in parasite uptake and dendritic cell maturation (2004) Journal of Cell Science, 117, pp. 315-325Wilson, M.E., Pearson, R.D., Evidence that Leishmania donovani utilizes a mannose receptor on human mononuclear phagocytes to establish intracellular parasitism (1986) The Journal of Immunology, 136, pp. 4681-4688Woelbing, F., Kostka, S.L., Moelle, K., Belkaid, Y., Sunderkoetter, C., Verbeek, S., Waisman, A., von Stebut, E., Uptake of Leishmania major by dendritic cells is mediated by Fcgamma receptors and facilitates acquisition of protective immunity (2006) The Journal of Experimental Medicine, 203, pp. 177-18

Presence of autoantibodies against HeLa small nuclear ribonucleoproteins in chagasic and non-chagasic cardiac patients

We detected anti-human small nuclear ribonucleoprotein (snRNP) autoantibodies in chagasic patients by different immunological methods using HeLa snRNPs. ELISA with Trypanosoma cruzi total lysate antigen or HeLa human U small nuclear ribonucleoproteins (UsnRNPs) followed by incubation with sera from chronic chagasic and non-chagasic cardiac patients was used to screen and compare serum reactivity. Western blot analysis using a T. cruzi total cell extract was also performed in order to select some sera for Western blot and immunoprecipitation assays with HeLa nuclear extract. ELISA showed that 73 and 95% of chronic chagasic sera reacted with HeLa UsnRNPs and T. cruzi antigens, respectively. The Western blot assay demonstrated that non-chagasic cardiac sera reacted with high molecular weight proteins present in T. cruzi total extract, probably explaining the 31% reactivity found by ELISA. However, these sera reacted weakly with HeLa UsnRNPs, in contrast to the chagasic sera, which showed autoantibodies with human Sm (from Stefanie Smith, the first patient in whom this activity was identified) proteins (B/B', D1, D2, D3, E, F, and G UsnRNP). Immunoprecipitation reactions using HeLa nuclear extracts confirmed the reactivity of chagasic sera and human UsnRNA/RNPs, while the other sera reacted weakly only with U1snRNP. These findings agree with previously reported data, thus supporting the idea of the presence of autoimmune antibodies in chagasic patients. Interestingly, non-chagasic cardiac sera also showed reactivity with T. cruzi antigen and HeLa UsnRNPs, which suggests that individuals with heart disease of unknown etiology may develop autoimmune antibodies at any time. The detection of UsnRNP autoantibodies in chagasic patients might contribute to our understanding of how they develop upon initial T. cruzi infection

Expression Of Hypoxia-inducible Factor 1α In Mononuclear Phagocytes Infected With Leishmania Amazonensis

Increasing evidence indicates that hypoxia-inducible factor 1α (HIF-1α) can be upregulated in different cell types by nonhypoxic stimuli such as growth factors, cytokines, nitric oxide, lipopolysaccharides and a range of infectious microorganisms. In this study, the ability of the following mononuclear phagocytes to express HIF-1α is reported: mouse macrophages (mMΦ), human macrophages (hMΦ) and human dendritic cells (DC), parasitized in vitro with Leishmania amazonensis; as assessed by immunofluorescence microscopy. A logical explanation for HIF-1α expression might be that the mononuclear phagocytes became hypoxic after L. amazonensis infection. Using the hypoxia marker pimonidazole, observation revealed that L. amazonensis-infected cells were not hypoxic. In addition, experiments using a HIF-1α inhibitor, CdCl2, to treat L. amazonensis-infected macrophage cultures showed reduced parasite survival. These studies indicated that HIF-1α could play a role in adaptative and immune responses of mononuclear phagocytes presenting infection by the parasite L. amazonensis. © 2007 Elsevier B.V. All rights reserved.1142119125Wang, G.L., Semenza, G.L., Purification and characterization of hypoxia-inducible factor 1 (1995) J Biol Chem, 270, pp. 1230-1237Semenza, G.L., Regulation of physiological responses to continuous and intermittent hypoxia by hypoxia-inducible factor 1 (2006) Exp Physiol, 1, pp. 803-806Salceda, S., Caro, J., Hypoxia-inducible factor 1α (HIF-1α) protein is rapidly degraded by the ubiquitin-proteasome system under normoxic conditions. 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Evidence for a role of hypoxia-inducible factor-1 in bacterial infections (2005) Circulation, 111, pp. 1054-1062Peyssonnaux, C., Datta, V., Cramer, T., Doedens, A., Theodorakis, E.A., Gallo, R.L., HIF-1alpha expression regulates the bactericidal capacity of phagocytes (2005) J Clin Invest, 115, pp. 1806-1815Spear, W., Chan, D., Coppens, I., Johnson, R.S., Giaccia, A., Blader, I.J., The host cell transcription factor hypoxia-inducible factor 1 is required for Toxoplasma gondii growth and survival at physiological oxygen levels (2006) Cell Microbiol, 8, pp. 339-352Rupp, J., Gieffers, J., Klinger, M., van Zandbergen, G., Wrase, R., Maass, M., Chlamydia pneumoniae directly interferes with HIF-1alpha stabilization in human host cells (2007) Cell Microbiol, 9, pp. 2181-2191Barbieri, C.L., Giorgio, S., Merjan, A.J., Figueiredo, E.N., Glycosphingolipid antigens of Leishmania (Leishmania) amazonensis amastigotes identified by use of a monoclonal antibody (1993) Infect Immun, 61, pp. 2131-2137Degrossoli, A., Colhone, M.C., Arrais-Silva, W.W., Giorgio, S., Hypoxia modulates expression of the 70-kD heat shock protein and reduces Leishmania infection in macrophages (2004) J Biomed Sci, 11, pp. 847-854Bosque, F., Saravia, N.G., Valderrama, L., Milon, G., Distinct innate and acquired immune responses to Leishmania in putative susceptible and resistant human populations endemically exposed to L. (Viannia) panamensis infection (2000) Scand J Immunol, 51, pp. 533-541Nair, S.K., Boczkowski, D., Morse, M., Cumming, R.I., Lyerly, H.K., Gilboa, E., Induction of primary carcinoembryonic antigen (CEA)-specific cytotoxic T lymphocytes in vitro using human dendritic cells transfected with RNA (1998) Nat Biotechnol, 16, pp. 364-369Bosetto, M.C., Giorgio, S., Leishmania amazonensis: multiple receptor-ligand interactions are involved in amastigote infection of human dendritic cells (2007) Exp Parasitol, 116, pp. 306-310Degrossoli, A., Giorgio, S., Functional alterations in macrophages after hypoxia selection (2007) Exp Biol Med (Maywood), 232, pp. 88-95Colhone, M.C., Arrais-Silva, W.W., Picoli, C., Giorgio, S., Effect of hypoxia on macrophage infection by Leishmania amazonensis (2004) J Parasitol, 90, pp. 510-515Chun, Y.S., Choi, E., Kim, G.T., Choi, H., Kim, C.H., Lee, M.J., Cadmium blocks hypoxia-inducible factor (HIF)-1-mediated response to hypoxia by stimulating the proteasome-dependent degradation of HIF-1alpha (2000) Eur J Biochem, 267, pp. 4198-4204Mikami, M., Sadahira, Y., Haga, A., Otsuki, T., Wada, H., Sugihara, T., Hypoxia-inducible factor-1 drives the motility of the erythroid progenitor cell line, UT-7/Epo, via autocrine motility factor (2005) Exp Hematol, 33, pp. 531-541Chapman, J.D., Franko, A.J., Sharplin, J., A marker for hypoxic cells in tumours with potential clinical applicability (1981) Br J Cancer, 43, pp. 546-550Raleigh, J.A., Chou, S.C., Arteel, G.E., Horsman, M.R., Comparisons among pimonidazole binding, oxygen electrode measurements, and radiation response in C3H mouse tumors (1999) Radiat Res, 151, pp. 580-589Doege, K., Heine, S., Jensen, I., Jelkmann, W., Metzen, E., Inhibition of mitochondrial respiration elevates oxygen concentration but leaves regulation of hypoxia-inducible factor (HIF) intact (2005) Blood, 106, pp. 2311-2317Tanaka, H., Yamamoto, M., Hashimoto, N., Miyakoshi, M., Tamakawa, S., Yoshie, M., Hypoxia-independent overexpression of hypoxia-inducible factor 1alpha as an early change in mouse hepatocarcinogenesis (2006) Cancer Res, 66, pp. 11263-11270Sandau, K.B., Fandrey, J., Brune, B., Accumulation of HIF-1alpha under the influence of nitric oxide (2001) Blood, 97, pp. 1009-1015Chavez, J.C., LaManna, J.C., Activation of hypoxia-inducible factor-1 in the rat cerebral cortex after transient global ischemia: potential role of insulin-like growth factor-1 (2002) J Neurosci, 22, pp. 8922-8931Mateo, J., Garcia-Lecea, M., Cadenas, S., Hernandez, C., Moncada, S., Regulation of hypoxia-inducible factor-1alpha by nitric oxide through mitochondria-dependent and -independent pathways (2003) Biochem J, 376, pp. 537-544Blouin, C.C., Page, E.L., Soucy, G.M., Richard, D.E., Hypoxic gene activation by lipopolysaccharide in macrophages: implication of hypoxia-inducible factor 1alpha (2004) Blood, 103, pp. 1124-1130Zarember, K.A., Malech, H.L., HIF-1alpha: a master regulator of innate host defenses? 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Molecular Differentiation Of Leishmania Protozoarium Using Cds Quantum Dots As Biolabels

In this work we applied core-shell CdS/Cd(OH)2 quantum dots (QDs) as fluorescent labels in the Leishmania amazonensis protozoarium. The nanocrystals (8-9 nm) are obtained via colloidal synthesis in aqueous medium, with final pH=7 using sodium polyphosphate as the stabilizing agent. The surface of the particles is passivated with a cadmium hydroxide shell and the particle surface is functionalized with glutaraldehyde. The functionalized and non-functionalized particles were conjugated to Leishmania organisms in the promastigote form. The marked live organisms were visualized using confocal microscopy. The systems exhibit a differentiation of the emission color for the functionalized and non-functionalized particles suggesting different chemical interactions with the promastigote moieties. Two photon emision spectra (λexc=795nm) were obtained for the promastigotes labeled with the functionalized QDs showing a significant spectral change compared to the original QDs suspension. These spectral changes are discussed in terms of the possible energy deactivation processes.6097Medinitz, I.L., Tetsuo Uyeda, H., Goldman, E.R., Mattoussi, H., Quantum dot bioconjugates for imaging, labeling and sensing (2005) Nature Materials, 4, pp. 435-446Chen, F., Gerion, D., Fluorescent CdSe/ZnS nanocrystal-peptide conjugates for long-term, nontoxic imaging and nuclear targeting in living cells (2004) Nano Letters, 4 (10), pp. 27-1832Alivisatos, A.P., Semiconductor clusters, nanocrystals, and quantum dots (1996) Science, 271, pp. 933-937Medintz, I.L., Konnert, J.H., Clapp, A.R., Stanish, I., Twigg, M.E., Mattoussi, H., A fluorescence resonance energy transfer-derived structure of a quantum dot-protein bioconjugate nanoassembly PNAS, 101 (26), pp. 9612-9617Mamedova, N.N., Kotov, N.A., Rogach, A.L., Studer, J., Albumin-CdTe nanoparticle bioconjugates: Preparation, structure, and interunit energy transfer with antenna effect (2001) Nano Lett., 1, pp. 281-286Farias, P.M.A., Santos, B.S., De Menezes, F.D., Ferreira, R.C., Barjas-Castro, M.L., Castro, V., Moura Lima, P.R., Cesar, C.L., Investigation of red blood cell antigens with highly fluorescent and stable semiconductor quantum dots (2005) Journal of Biomedical Optics, 10 (4), pp. 440231-1044234Farias, P.M.A., Santos, B.S., De Menezes, F.D., Ferreira, R.C., Barjas-Castro, M.L., Castro, V., Moura Lima, P.R., Cesar, C.L., Core-shell CdS/Cd(OH)2 quantum dots: Synthesis and bioconjugation to target red cells antigens (2005) Journal of Microscopy, 219 (3), pp. 103-108Petrov, D.V., Santos, B.S., Pereira, G.A.L., Donegá, C.M., Size and band-gap dependences of the hiperpolarizability of CdxZnl-xS nanocrystals (2002) J. Phys. Chem. B, 106, pp. 5325-5334Santos, B.S., (2002) Obtenção de Nanopartículas de CdS em Sistemas Amorfos e a Investigação de suas Propriedades Ópticas Não-lineares em Meio Aquoso, , Doctoral Thesis, Recife, BrazilSolomons, G., Fhryle, C., (2004) Organic Chemistry, 7th Ed., , Wiley, New YorkGao, X.M., Rhodes, J., An essential role for constitutive Schiff base-forming ligands in antigen presentation to murine T cell clones (1990) The Journal of Immunology, 144 (8), pp. 2883-2890Silveira, T.G.V., Arraes, S.M.A.A., Bertolini, D.A., Teodora, U., Lonardoni, M.V.C., Roberto, A.C.B.S., Sobrinho, M.R., Shaw, J., Observações sobre o diagnóstico laboratorial e a epidemiologia da leishmaniose tegumentar no Estado do Paraná, sul do Brasil (1999) Revista da Sociedade Brasileira de Medicina Tropical, 32 (4), pp. 413-42