title: Intact reducing glycan promotes the specific immune response to lacto-N-neotetraose-BSA neoglycoconjugates.
abstract: The mammalian immune system responds to eukaryotic glycan antigens during infections, cancer, and autoimmune disorders, but the immunological bases for such responses are unclear. Conjugate vaccines containing bacterial polysaccharides linked to carrier proteins (neoglycoconjugates) have proven successful, but these often contain repeating epitopes and the reducing end of the glycan is less important, unlike typical glycan determinants in eukaryotes, which are shorter in length and may include the reducing end. Here, we have compared the effects of two linkage methods, one that opens the ring at the reducing end of the glycan, and one that leaves the reducing end closed, on the glycan specificity of the vaccine response in rabbits and mice. We immunized rabbits and mice with bovine serum albumin (BSA) conjugates of synthetic open- and closed-ring forms (OR versus CR) of a simple tetrasaccharide lacto-N-neotetraose (LNnT, Galβ1-4GlcNAcβ1-3Galβ1-4Glc), and tested reactivity to the immunogens and several related glycans in both OR and CR versions on glycan microarrays. We found that in rabbits the immune response to the CR conjugate was directed toward the glycan, whereas the OR conjugate elicited antibodies to the reducing end of the glycan and linker region but not specifically to the glycan itself. Unexpectedly, mice did not generate a glycan-specific response to the CR conjugate. Our findings indicate that the reducing end of the sugar is crucial for generation of a glycan-specific response to some eukaryotic vaccine epitopes, and that there are species-specific differences in the ability to make a glycan-specific response to some glycoconjugates. These findings warrant further investigation with regard to rational design of glycoconjugate vaccines.
authors: The Glycomics Center and Department of Biochemistry, Emory University School of Medicine, O. Wayne Rollins Research Center, Suite 4001, 1510 Clifton Road, Atlanta, Georgia 30322, United States.
authors: Nina S
authors: NS
authors: Prasanphanich
authors: The Glycomics Center and Department of Biochemistry, Emory University School of Medicine, O. Wayne Rollins Research Center, Suite 4001, 1510 Clifton Road, Atlanta, Georgia 30322, United States.
authors: Xuezheng
authors: X
authors: Song
authors: The Glycomics Center and Department of Biochemistry, Emory University School of Medicine, O. Wayne Rollins Research Center, Suite 4001, 1510 Clifton Road, Atlanta, Georgia 30322, United States.
authors: Jamie
authors: J
authors: Heimburg-Molinaro
authors: The Glycomics Center and Department of Biochemistry, Emory University School of Medicine, O. Wayne Rollins Research Center, Suite 4001, 1510 Clifton Road, Atlanta, Georgia 30322, United States.
authors: Anthony E
authors: AE
authors: Luyai
authors: The Glycomics Center and Department of Biochemistry, Emory University School of Medicine, O. Wayne Rollins Research Center, Suite 4001, 1510 Clifton Road, Atlanta, Georgia 30322, United States.
authors: Yi
authors: Y
authors: Lasanajak
authors: The Glycomics Center and Department of Biochemistry, Emory University School of Medicine, O. Wayne Rollins Research Center, Suite 4001, 1510 Clifton Road, Atlanta, Georgia 30322, United States.
authors: Christopher E
authors: CE
authors: Cutler
authors: The Glycomics Center and Department of Biochemistry, Emory University School of Medicine, O. Wayne Rollins Research Center, Suite 4001, 1510 Clifton Road, Atlanta, Georgia 30322, United States.
authors: David F
authors: DF
authors: Smith
authors: The Glycomics Center and Department of Biochemistry, Emory University School of Medicine, O. Wayne Rollins Research Center, Suite 4001, 1510 Clifton Road, Atlanta, Georgia 30322, United States.
authors: Richard D
authors: RD
authors: Cummings
mesh_terms: D000818:Animals; D002417:Cattle; D005260:Female; D006023:Glycoproteins / Q000737:chemistry / Q000276:immunology*; D007111:Immunity, Cellular / Q000276:immunology*; D051379:Mice; D008810:Mice, Inbred C57BL; D009844:Oligosaccharides / Q000737:chemistry / Q000276:immunology*; D011134:Polysaccharides / Q000737:chemistry / Q000276:immunology*; D011817:Rabbits; D012710:Serum Albumin, Bovine / Q000737:chemistry / Q000276:immunology*
chemical_list: D006023:Glycoproteins; D009844:Oligosaccharides; D011134:Polysaccharides; D012710:Serum Albumin, Bovine; C013084:lacto-N-neotetraose