The Cell Surface Receptor DC-SIGN Discriminates betweenMycobacterium Species through Selective Recognition of the Mannose Caps on Lipoarabinomannan

Abstract

Interactions between dendritic cells (DCs) and Mycobacterium tuberculosis, the etiological agent of tuberculosis, most likely play a key role in anti-mycobacterial immunity. We have recently shown that M. tuberculosis binds to and infects DCs through ligation of the DC-specific intercellular adhesion molecule-3-grabbing nonintegrin (DC-SIGN) and that M. tuberculosis mannose-capped lipoarabinomannan (ManLAM) inhibits binding of the bacilli to the lectin, suggesting that ManLAM might be a key DC-SIGN ligand. In the present study, we investigated the molecular basis of DC-SIGN ligation by LAM. Contrary to what was found for slow growing mycobacteria, such as M. tuberculosis and the vaccine strainMycobacterium bovis bacillus Calmette-Guérin, our data demonstrate that the fast growing saprophytic speciesMycobacterium smegmatis hardly binds to DC-SIGN. Consistent with the former finding, we show that M. smegmatis-derived lipoarabinomannan, which is capped by phosphoinositide residues (PILAM), exhibits a limited ability to inhibit M. tuberculosis binding to DC-SIGN. Moreover, using enzymatically demannosylated and chemically deacylated ManLAM molecules, we demonstrate that both the acyl chains on the ManLAM mannosylphosphatidylinositol anchor and the mannooligosaccharide caps play a critical role in DC-SIGN-ManLAM interaction. Finally, we report that DC-SIGN binds poorly to the PILAM and uncapped AraLAM-containing species Mycobacterium fortuitum and Mycobacterium chelonae, respectively. Interestingly, smooth colony-formingMycobacterium avium, in which ManLAM is capped with single mannose residues, was also poorly recognized by the lectin. Altogether, our results provide molecular insight into the mechanisms of mycobacteria-DC-SIGN interaction, and suggest that DC-SIGN may act as a pattern recognition receptor and discriminate between Mycobacterium species through selective recognition of the mannose caps on LAM molecules. Interactions between dendritic cells (DCs) and Mycobacterium tuberculosis, the etiological agent of tuberculosis, most likely play a key role in anti-mycobacterial immunity. We have recently shown that M. tuberculosis binds to and infects DCs through ligation of the DC-specific intercellular adhesion molecule-3-grabbing nonintegrin (DC-SIGN) and that M. tuberculosis mannose-capped lipoarabinomannan (ManLAM) inhibits binding of the bacilli to the lectin, suggesting that ManLAM might be a key DC-SIGN ligand. In the present study, we investigated the molecular basis of DC-SIGN ligation by LAM. Contrary to what was found for slow growing mycobacteria, such as M. tuberculosis and the vaccine strainMycobacterium bovis bacillus Calmette-Guérin, our data demonstrate that the fast growing saprophytic speciesMycobacterium smegmatis hardly binds to DC-SIGN. Consistent with the former finding, we show that M. smegmatis-derived lipoarabinomannan, which is capped by phosphoinositide residues (PILAM), exhibits a limited ability to inhibit M. tuberculosis binding to DC-SIGN. Moreover, using enzymatically demannosylated and chemically deacylated ManLAM molecules, we demonstrate that both the acyl chains on the ManLAM mannosylphosphatidylinositol anchor and the mannooligosaccharide caps play a critical role in DC-SIGN-ManLAM interaction. Finally, we report that DC-SIGN binds poorly to the PILAM and uncapped AraLAM-containing species Mycobacterium fortuitum and Mycobacterium chelonae, respectively. Interestingly, smooth colony-formingMycobacterium avium, in which ManLAM is capped with single mannose residues, was also poorly recognized by the lectin. Altogether, our results provide molecular insight into the mechanisms of mycobacteria-DC-SIGN interaction, and suggest that DC-SIGN may act as a pattern recognition receptor and discriminate between Mycobacterium species through selective recognition of the mannose caps on LAM molecules. The interaction between Mycobacterium tuberculosis and host dendritic cells (DCs) 1The abbreviations used are: DC, dendritic cell; DC-SIGN, DC-specific intercellular adhesion molecule-3-grabbing nonintegrin; BCG, bacillus Calmette-Guérin; ICAM, intercellular adhesion molecule; Mφ, macrophage; ManLAM, mannose-capped lipoarabinomannan; αManLAM, α-exomannosidase-treated ManLAM; dManLAM, deacylated ManLAM; PILAM, phosphoinositide-capped lipoarabinomannan; AraLAM, uncapped LAM; MPI, mannosylphosphatidylinositol; CE-LIF, capillary electrophoresis coupled to laser-induced fluorescence; APTS, 1-aminopyrene-3,6,8-trisulfonate; IL, interleukin; MR, mannose receptor; TLR, toll-like receptor is thought to be critical for mounting a protective anti-mycobacterial immune response and for determining the outcome of infection (1Inaba K. Inaba M. Naito M. Steinman R.M. J. Exp. Med. 1993; 178: 479-488Google Scholar, 2Demangel C. Bean A.G. Martin E. Feng C.G. Kamath A.T. Britton W.J. Eur. J. Immunol. 1999; 29: 1972-1979Google Scholar, 3Tascon R.E. Soares C.S. Ragno S. Stavropoulos E. Hirst E.M. Colston M.J. Immunology. 2000; 99: 473-480Google Scholar, 4Flynn J.L. Chan J. Annu. Rev. Immunol. 2001; 19: 93-129Google Scholar). However, the molecular bases of DC infection by mycobacteria remain poorly understood. We have recently shown that M. tuberculosis, as well as the vaccine strain Mycobacterium bovis bacillus Calmette-Guérin (BCG), use the DC-specific intercellular adhesion molecule-3 (ICAM-3)-grabbing nonintegrin (DC-SIGN) to bind to and enter human DCs (5Tailleux L. Schwartz O. Herrmann J.-L. Pivert E. Jackson M. Amara A. Legrés L. Dreher D. Nicod L.P. Gluckman J.C. Lagrange P.H. Gicquel B. Neyrolles O. J. Exp. Med. 2003; 197: 121-127Google Scholar), a feature that may allow the bacillus to persist within a unique immature compartment of the cells (6Tailleux L. Neyrolles O. Honoré-Bouakline S. Perret E. Sanchez F. Abastado J.-P. Lagrange P.H. Gluckman J.C. Rosenzwajg M. Herrmann J.-L. J. Immunol. 2003; (in press)Google Scholar). DC-SIGN/CD209 is a calcium-dependent (C-type) transmembrane lectin that contains a single carbohydrate recognition domain at its extracellular C-terminal end. It is expressed on DCs as well as on some macrophage (Mφ) subsets, including alveolar Mφs (7Lee B. Leslie G. Soilleux E. O'Doherty U. Baik S. Levroney E. Flummerfelt K. Swiggard W. Coleman N. Malim M. Doms R.W. J. Virol. 2001; 75: 12028-12038Google Scholar,8Soilleux E.J. Morris L.S. Leslie G. Chehimi J. Luo Q. Levroney E. Trowsdale J. Montaner L.J. Doms R.W. Weissman D. Coleman N. Lee B. J. Leukocyte Biol. 2002; 71: 445-457Google Scholar). DC-SIGN has been described initially as a receptor for ICAM-3 and ICAM-2, as well as for human and simian immunodeficiency viruses, enabling the trans infection of susceptible CD4+T lymphocytes by these viruses (9Geijtenbeek T.B. Engering A. Van Kooyk Y. J. Leukocyte Biol. 2002; 71: 921-931Google Scholar, 10Geijtenbeek T.B. Krooshoop D.J. Bleijs D.A. van Vliet S.J. van Duijnhoven G.C. Grabovsky V. Alon R. Figdor C.G. van Kooyk Y. Nat. Immunol. 2000; 1: 353-357Google Scholar, 11Curtis B.M. Scharnowske S. Watson A.J. Proc. Natl. Acad. Sci. U. S. A. 1992; 89: 8356-8360Google Scholar, 12Geijtenbeek T.B. Kwon D.S. Torensma R. van Vliet S.J. van Duijnhoven G.C. Middel J. Cornelissen I.L. Nottet H.S. KewalRamani V.N. Littman D.R. Figdor C.G. van Kooyk Y. Cell. 2000; 100: 587-597Google Scholar). Thereafter, it was shown to bind to other microbes, namely Ebola virus and Leishmania pifanoi (13Strohmeier G.R. Fenton M.J. Microbes Infect. 1999; 1: 709-717Google Scholar, 14Colmenares M. Puig-Kroger A. Pello O.M. Corbi A.L. Rivas L. J. Biol. Chem. 2002; 277: 36766-36769Google Scholar). The DC-SIGN carbohydrate recognition domain binds to mannose-rich glycoconjugates (15Feinberg H. Mitchell D.A. Drickamer K. Weis W.I. Science. 2001; 294: 2163-2166Google Scholar), a feature that is consistent with our finding that M. tuberculosis lipoarabinomannan (termed ManLAM; see below), a highly mannosylated surface lipoglycan, might be a key mycobacterial ligand for DC-SIGN (5Tailleux L. Schwartz O. Herrmann J.-L. Pivert E. Jackson M. Amara A. Legrés L. Dreher D. Nicod L.P. Gluckman J.C. Lagrange P.H. Gicquel B. Neyrolles O. J. Exp. Med. 2003; 197: 121-127Google Scholar). Indeed, purified M. tuberculosis-derived ManLAM was found to inhibit the binding ofM. tuberculosis to human monocyte-derived DCs, as well as to recombinant HeLa-derived cells expressing DC-SIGN. LAM is a major component of the mycobacterial cell wall. It contains a carbohydrate backbone composed of d-mannan andd-arabinan (Fig.1). The mannan core is attached to an acylated mannosylphosphatidylinositol (MPI) anchor at its reducing end; the arabinan domain is capped with either mannose residues in so-called ManLAMs or with phosphoinositide motifs in so-called PILAMs (16Chatterjee D. Khoo K.H. Glycobiology. 1998; 8: 113-120Google Scholar, 17Vercellone A. Nigou J. Puzo G. Front Biosci. 1998; 3: e149-e163Google Scholar), or uncapped in so-called AraLAM (40Guérardel Y. Maes E. Elass E. Leroy Y. Timmerman P. Besra G.S. Locht C. Strecker G. Kremer L. J. Biol. Chem. 2002; 277: 30635-30648Google Scholar). The caps of ManLAMs consist of mono-, α(1→2)-di-, and α(1→2)-tri-mannopyranosides, with dimannopyranosides being the most abundant motif (18Nigou J. Vercellone A. Puzo G. J. Mol. Biol. 2000; 299: 1353-1362Google Scholar, 19Nigou J. Gilleron M. Cahuzac B. Bounery J.D. Herold M. Thurnher M. Puzo G. J. Biol. Chem. 1997; 272: 23094-23103Google Scholar, 20Gilleron M. Bala L. Brando T. Vercellone A. Puzo G. J. Biol. Chem. 2000; 275: 677-684Google Scholar). So far, ManLAMs have been detected in slow growing mycobacteria only. These include various strains of M. tuberculosis,M. bovis BCG, the leprosy agentMycobacterium leprae, and the opportunistic species Mycobacterium avium (16Chatterjee D. Khoo K.H. Glycobiology. 1998; 8: 113-120Google Scholar, 17Vercellone A. Nigou J. Puzo G. Front Biosci. 1998; 3: e149-e163Google Scholar, 21Khoo K.H. Dell A. Morris H.R. Brennan P.J. Chatterjee D. J. Biol. Chem. 1995; 270: 12380-12389Google Scholar, 22Khoo K.H. Tang J.B. Chatterjee D. J. Biol. Chem. 2001; 276: 3863-3871Google Scholar). By contrast, PILAM or AraLAM expression seems to be fairly limited to fast growing mycobacteria, including nonpathogenic Mycobacterium smegmatis (16Chatterjee D. Khoo K.H. Glycobiology. 1998; 8: 113-120Google Scholar, 17Vercellone A. Nigou J. Puzo G. Front Biosci. 1998; 3: e149-e163Google Scholar, 21Khoo K.H. Dell A. Morris H.R. Brennan P.J. Chatterjee D. J. Biol. Chem. 1995; 270: 12380-12389Google Scholar, 23Gilleron M. Himoudi N. Adam O. Constant P. Venisse A. Riviere M. Puzo G. J. Biol. Chem. 1997; 272: 117-124Google Scholar), Mycobacterium chelonae(40Guérardel Y. Maes E. Elass E. Leroy Y. Timmerman P. Besra G.S. Locht C. Strecker G. Kremer L. J. Biol. Chem. 2002; 277: 30635-30648Google Scholar), and Mycobacterium fortuitum. 2L. Bala, M. Gilleron, M. Rivière, and G. Puzo, unpublished data. In addition to their structural role in organizing of the cell wall, LAMs are known to be potent inducers of various cytokines when in contact with mammalian phagocytic cells (24Nigou J. Gilleron M. Rojas M. Garcia L.F. Thurnher M. Puzo G. Microbes Infect. 2002; 4: 945-953Google Scholar). We have shown that the slow growing mycobacteria M. tuberculosis and M. bovis BCG, which express ManLAM, interact with human DCs through DC-SIGN and that purifiedM. tuberculosis-derived ManLAM inhibitsM. tuberculosis binding to recombinant HeLa-derived cells expressing DC-SIGN and to monocyte-derived DCs. The goal of the present report was to obtain a better understanding of the molecular determinants of the LAM molecule involved in binding to DC-SIGN. Using a DC-SIGN-expressing recombinant cell line as a readout, we first report that DC-SIGN binds poorly to the fast growing species M. smegmatis and that M. smegmatis-derived PILAM, which lacks mannose caps, exhibits a very limited ability to inhibit M. tuberculosis binding to the lectin. Using various chemically or enzymatically generated variants of the ManLAM molecule, we further demonstrate that both the acyl chains on the MPI anchor and the mannose-capping residues play a key role in the ManLAM-DC-SIGN ligation process. Moreover, we show that DC-SIGN does not bind to the PILAM- and AraLAM-containing species M. fortuitum and M. chelonae, respectively. Altogether, our findings provide evidences that DC-SIGN may discriminate between ManLAM-containing slow growers, such as M. tuberculosis, and nonpathogenic PILAM-containing fast growers, such as M. smegmatis, through a high affinity for mannose-capping residues on ManLAM. DC-SIGN+ HeLa (HeLa-DC) cells were obtained by transducing HeLa cells with the retroviral vector TRIP-ΔU3 encoding for human DC-SIGN (25Halary F. Amara A. Lortat-Jacob H. Messerle M. Delaunay T. Houlès C. Fieschi F. Arenzana-Seisdedos F. Moreau J.-F. Déchanet- Merville J. Immunity. 2002; 17: 653-664Google Scholar). HeLa and HeLa-DC cells were propagated in RPMI 1640 (Invitrogen) supplemented with 10% fetal calf serum (Dutscher, Brumath, France).M. tuberculosis H37Rv, M. smegmatismc2155, and clinical isolates of M. fortuitum,M. chelonae, and M. avium(smooth colony-forming) were propagated in 7H9 medium containing 10% albumin-dextrose-catalase supplement. ManLAM from M. bovis BCG Pasteur and PILAM from M. smegmatis were purified as described previously (19Nigou J. Gilleron M. Cahuzac B. Bounery J.D. Herold M. Thurnher M. Puzo G. J. Biol. Chem. 1997; 272: 23094-23103Google Scholar,23Gilleron M. Himoudi N. Adam O. Constant P. Venisse A. Riviere M. Puzo G. J. Biol. Chem. 1997; 272: 117-124Google Scholar, 26Nigou J. Gilleron M. Brando T. Vercellone A. Puzo G. Glycoconj. J. 1999; 16: 257-264Google Scholar). M. tuberculosis H37Rv-purified ManLAM was a kind gift from the Colorado State University. dManLAM was prepared by incubating ManLAM (200 μg) in 200 μl of NaOH 0.1 m for 2 h at 37 °C. After neutralization with 200 μl of HCl, 0.1m, the reaction products were dialyzed against water and freeze-dried. αManLAM was prepared by incubating ManLAM (200 μg) for 6 h at 37 °C in 30 μl of a jack beans α-mannosidase (Sigma) solution (2 mg/ml, 0.1 m sodium acetate buffer, pH 4.5, 1 mm ZnSO4). After a second addition of 50 μl of enzyme solution, the reaction was continued overnight. The reaction products were then dialyzed against 50 mmNH4CO3, pH 7.6. Elimination of α-mannosidase was achieved by denaturation (2 min at 110 °C) followed by overnight tryptic digestion (37 °C, 3.2 μg of trypsin). αManLAM was recovered after dialysis against water, freeze-dried, and analyzed for cap contents by CE-LIF as previously described (27Nigou J. Zelle-Rieser C. Gilleron M. Thurnher M. Puzo G. J. Immunol. 2001; 166: 7477-7485Google Scholar). Briefly, ManLAM or αManLAM (1 μg) was submitted to mild acidic hydrolysis (15 μl of HCl, 0.1 m, for 20 min at 110 °C) in the presence of mannoheptose (100 pmol) as the internal standard. The reaction products were then submitted to 1-aminopyrene-3,6,8-trisulfonate (APTS) tagging and subjected to CE-LIF analysis. Separations were performed using an uncoated, fused silica capillary column (50 μm internal diameter; 40 cm effective length; 47 cm total length; Sigma), and analyses were carried out at a temperature of 25 °C with an applied voltage of 20 kV using acetic acid 1% (w/v), triethylamine 30 mm in water, pH 3.5, as a running electrolyte. The amount of each cap motif was determined relative to the internal standard. Cells were infected at a multiplicity of infection of 1 bacterium/cell for 4 h at 4 °C in RPMI 1640, washed extensively in RPMI 1640, and analyzed by scoring colony-forming units after plating on agar and incubation at 37 °C. In binding inhibition experiments, cells were preincubated for 1 h at 4 °C with 10 μg/ml of the indicated components. These components were left in the culture medium during the infection process. Mycobacterial species can be divided into slow and fast growers. To a better understanding of the molecular basis of their ligation to DC-SIGN, we first the relative ability of the slow growing species M. tuberculosis the fast growing saprophytic species M. smegmatis to bind to the lectin. binding was performed on HeLa-derived cells expressing or not DC-SIGN and we tuberculosis was found to bind to HeLa-DC to HeLa cells and in a multiplicity of not smegmatis binding to HeLa-DC was found to be to HeLa cells 2 finding that M. tuberculosis ManLAM can inhibit M. tuberculosis binding to DC-SIGN that the ability of M. smegmatis to bind to HeLa-DC cells may be to the of M. smegmatis PILAM to bind to the lectin. To we performed a M. tuberculosis binding on HeLa-DC cells that been preincubated or not with LAM from various mycobacterial mannan and M. as well as M. bovis ManLAMs were found to inhibit mycobacterial binding to HeLa-DC cells by as as 2 By contrast, M. smegmatis-derived PILAM was found to inhibit poorly the binding of M. HeLa-DC Interestingly, PILAM was found to smegmatis binding to HeLa-DC cells not The that ManLAM inhibits M. tuberculosis binding to DC-SIGN as well as M. tuberculosis-derived ManLAM does is consistent with our that M. bovis BCG binds to DC-SIGN to the as M. tuberculosis and with the known structural between ManLAMs from M. bovis BCG tuberculosis (18Nigou J. Vercellone A. Puzo G. J. Mol. Biol. 2000; 299: 1353-1362Google Scholar). DC-SIGN is a lectin and PILAMs are of mannose caps we that the results described might that ManLAM residues may be the ManLAM recognized by the lectin. To we M. bovis ManLAM with to obtain ManLAM of mannose caps The reaction was by CE-LIF as previously described (18Nigou J. Vercellone A. Puzo G. J. Mol. Biol. 2000; 299: 1353-1362Google Scholar, J. Zelle-Rieser C. Gilleron M. Thurnher M. Puzo G. J. Immunol. 2001; 166: 7477-7485Google Scholar). obtained for αManLAM is in A. to mannooligosaccharide caps, α(1→2)-di-, and α(1→2)-tri-mannopyranosides, were indicated that of cap was The ability of αManLAM to tuberculosis binding to DC-SIGN was in binding In to ManLAM, αManLAM to inhibit mycobacterial binding to the lectin binding results were obtained when cells were with M. tuberculosis-derived αManLAM to the binding not These results that mannooligosaccharide caps are critical structural for inhibition of M. tuberculosis binding to DC-SIGN. MPI anchor has been shown previously to be involved in some of the of ManLAM, their binding to A. Puzo G. 1995; Scholar, S. Nigou J. Puzo G. Riviere M. J. Biol. Chem. 2000; 275: Scholar), we then the role of the acyl of the MPI anchor in ManLAM-DC-SIGN interaction. To M. bovis dManLAM was prepared by shown on dManLAM to inhibit M. tuberculosis binding to HeLa-DC that a acylated MPI anchor is for inhibition of mycobacterial binding to DC-SIGN. Finally, we to our finding was in species for which the LAM was In with what we the PILAM- and AraLAM-containing species M. fortuitum and M. were poorly recognized by DC-SIGN. Indeed, in a binding in M. fortuitum and M. to HeLa-DC cells and to HeLa not Interestingly, the ManLAM-containing slow M. avium was also found to bind poorly to DC-SIGN-expressing HeLa cells to HeLa data not is not ManLAM from smooth colony-forming M. avium, which is the used in our has been to be capped with single mannose residues of the and motifs found in M. bovis ManLAM K.H. Tang J.B. Chatterjee D. J. Biol. Chem. 2001; 276: 3863-3871Google Scholar). DC-SIGN does not bind to single mannose to mannosylated (15Feinberg H. Mitchell D.A. Drickamer K. Weis W.I. Science. 2001; 294: 2163-2166Google Scholar), it is likely that such ManLAM is not recognized by the lectin. These results the that DC-SIGN may mycobacteria from the tuberculosis only. Altogether, our results demonstrate that the DC-SIGN-ManLAM interaction both the MPI anchor acyl chains and the mannose residues from caps of the ManLAM recently for the binding of ManLAM to the human lectin S. Nigou J. Puzo G. Riviere M. J. Biol. Chem. 2000; 275: S. Puzo G. Riviere M. J. 2002; Scholar), the MPI are most likely involved in the of the ManLAM in in results in a in ManLAM and ManLAM to DC-SIGN. is likely to the ability of dManLAM to inhibit M. tuberculosis binding to HeLa-DC cells does not LAM acyl which are likely to be within the cell wall, can interact with the lectin in However, the be as our is of the of the acyl chains of the M. tuberculosis in binding to toll-like on phagocytic cells M. Brennan P.J. P.J. Science. 1999; Scholar). recognition of the ManLAM mannose-capping residues by DC-SIGN on the surface of DCs is likely to have for both the and of tuberculosis and other mycobacterial LAMs have various on phagocytic including Mφs and DCs (24Nigou J. Gilleron M. Rojas M. Garcia L.F. Thurnher M. Puzo G. Microbes Infect. 2002; 4: 945-953Google Scholar). PILAMs the of such as and and the of such as in a potent In not inhibit the of by PILAMs are as molecules, ManLAMs are as components A. Nigou J. Puzo G. Front Biosci. 1998; 3: e149-e163Google Scholar, J. Gilleron M. Rojas M. Garcia L.F. Thurnher M. Puzo G. Microbes Infect. 2002; 4: 945-953Google Scholar), which is consistent with the known ability of ManLAM-containing slow growing mycobacteria to immune mechanisms of their susceptible host Nat. Rev. Mol. Cell. Biol. 2001; Scholar). In our results demonstrate that ManLAM inhibits the of by human DCs, a DC-SIGN both the MPI anchor acyl chains and the mannose caps (27Nigou J. Zelle-Rieser C. Gilleron M. Thurnher M. Puzo G. J. Immunol. 2001; 166: 7477-7485Google Scholar). In (27Nigou J. Zelle-Rieser C. Gilleron M. Thurnher M. Puzo G. J. Immunol. 2001; 166: 7477-7485Google Scholar), on using we that ManLAM was through ligation of the mannose receptor is also involved in LAM mannose caps recognition L.S. J. Immunol. Scholar), out the that ManLAM act also through the ligation of DC-SIGN, which is Indeed, DC-SIGN ligation by ManLAM, either attached to the bacilli or in the through J. Biol. 2002; Scholar), is likely to major including cell of cytokines such as or C.G. van Kooyk Y. Nat. Rev. Immunol. 2002; Scholar). Interestingly, PILAMs not ManLAMs can cells in a S. E. A. Fenton M.J. J. Immunol. 1999; Scholar). It be of to the between phagocytic cell surface such as and DC-SIGN, and in response to mycobacterial including LAMs from various mycobacterial an it is that DC-SIGN can discriminate between fast growing saprophytic and slow growing or it was that mannose of the LAM was a unique feature of is to be the the species M. bovis BCG also contains mannose-capped LAM K.H. Dell A. Morris H.R. Brennan P.J. Chatterjee D. J. Biol. Chem. 1995; 270: 12380-12389Google Scholar). not M. bovis BCG can be in and in it may a of from to A. O. N. N. M. Scholar). Moreover, M. bovis BCG is from which a with M. tuberculosis R. M. P. C. K. T. C. G. Kremer K. S. van D. Proc. Natl. Acad. Sci. U. S. A. 2002; 99: Scholar). that mannose of the ManLAM molecule is a feature of mycobacteria that has been during the of M. bovis BCG In DC-SIGN be as a pattern recognition receptor R. Annu. Rev. Immunol. 2002; that has to mycobacteria through their surface In mycobacteria have mechanisms to host of the in with their fast We L. V. O. Schwartz and C. for of the and We P. for We Colorado State for the gift of purified M. tuberculosis ManLAM.