title: Synthetic and Immunological Studies of Mycobacterial Lipoarabinomannan Oligosaccharides and Their Protein Conjugates.
abstract: Lipoarabinomannan (LAM) is one of the major constituents of the Mycobacterium tuberculosis cell wall and an attractive molecular scaffold for antituberculosis drug and vaccine development. In this paper, a convergent strategy was developed for the synthesis of LAM oligosaccharides with an α-1,2-linked dimannopyranose cap at the nonreducing end. The strategy was highlighted by efficient coupling of separately prepared nonreducing end and reducing end oligosaccharides. Glycosylations were mainly achieved with thioglycoside donors, which gave excellent yields and stereoselectivity even for reactions between complex oligosaccharides. The strategy was utilized to successfully synthesize tetra-, hepta-, and undecasaccharides of LAM from d-arabinose in 10, 15, and 14 longest linear steps and 7.84, 7.50, and 2.59% overall yields, respectively. The resultant oligosaccharides with a free amino group at their reducing end were effectively conjugated with carrier proteins, including bovine serum albumin and keyhole limpet hemocyanin (KLH), via a bifunctional linker. Preliminary immunological studies on the KLH conjugates revealed that they could elicit robust antibody responses in mice and that the antigen structure had some influence on their immunological property, thus verifying the potential of the oligosaccharides for vaccine development and other immunological studies.
authors.affiliation: National Glycoengineering Research Center, School of Life Science, Shandong University , Jinan 250100, China.
authors.forename: Lizhen
authors.initials: L
authors.lastname: Wang
authors.affiliation: National Glycoengineering Research Center, School of Life Science, Shandong University , Jinan 250100, China.
authors.forename: Shaojie
authors.initials: S
authors.lastname: Feng
authors.affiliation: National Glycoengineering Research Center, School of Life Science, Shandong University , Jinan 250100, China.
authors.forename: Lian
authors.initials: L
authors.lastname: An
authors.affiliation: National Glycoengineering Research Center, School of Life Science, Shandong University , Jinan 250100, China.
authors.forename: Guofeng
authors.initials: G
authors.lastname: Gu
authors.affiliation: National Glycoengineering Research Center, School of Life Science, Shandong University , Jinan 250100, China.
authors.forename: Zhongwu
authors.initials: Z
authors.lastname: Guo
mesh_terms: D000276:Adjuvants, Immunologic / Q000138:chemical synthesis* / Q000737:chemistry / Q000378:metabolism; D000818:Animals; D000995:Antitubercular Agents / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D002473:Cell Wall / Q000737:chemistry* / Q000276:immunology; D008070:Lipopolysaccharides / Q000138:chemical synthesis* / Q000378:metabolism / Q000494:pharmacology; D051379:Mice; D009169:Mycobacterium tuberculosis / Q000737:chemistry* / Q000276:immunology; D009844:Oligosaccharides / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology
chemical_list: D000276:Adjuvants, Immunologic; D000995:Antitubercular Agents; D008070:Lipopolysaccharides; D009844:Oligosaccharides; C050016:lipoarabinomannan