Helicobacter pylori lipopolysaccharide structural domains and their recognition by immune proteins revealed with carbohydrate microarrays

abstract

The structural diversity of the lipopolysaccharides (LPSs) from Helicobacter pylori poses a challenge to establish accurate and strain-specific structure-function relationships in interactions with the host. Here, LPS structural domains from five clinical isolates were obtained and compared with the reference strain 26695. This was achieved combining information from structural analysis (GC-MS and ESI-MSn) with binding data after interrogation of a LPS-derived carbohydrate microarray with sequence-specific proteins. All LPSs expressed Lewisx/y and N-acetyllactosamine determinants. Ribans were also detected in LPSs from all clinical isolates, allowing their distinction from the 26695 LPS. There was evidence for 1,3-D-galactans and blood group H-type 2 sequences in two of the clinical isolates, the latter not yet described for H. pylori LPS. Furthermore, carbohydrate microarray analyses showed a strain-associated LPS recognition by the immune lectins DC-SIGN and galectin-3 and revealed distinctive LPS binding patterns by IgG antibodies in the serum from H. pylori-infected patients.

keywords

GASTRIC EPITHELIAL-CELLS; O-ANTIGEN CHAIN; BLOOD-GROUP-A; MOLECULAR MIMICRY; ANTIBODY-RESPONSE; GROUP-B; GROUP-H; STRAIN; LEWIS; SPECIFICITY

subject category

Chemistry, Applied; Chemistry, Organic; Polymer Science

authors

Silva, LM; Correia, VG; Moreira, ASP; Domingues, MRM; Ferreira, RM; Figueiredo, C; Azevedo, NF; Marcos-Pinto, R; Carneiro, F; Magalhaes, A; Reis, CA; Feizi, T; Ferreira, JA; Coimbra, MA; Palma, AS

Groups

G4 - Renewable Materials and Circular Economy

Projects

Collaboratory for Emerging Technologies, CoLab (EMERGING TECHNOLOGIES)

Glycan-human microbiome interaction: glycan diversity and recognition in the human gut with impact on health and nutrition; (GLYCOINTERACT)

acknowledgements

Thanks are due to the University of Aveiro and FCT - Fundacao para a Ciencia e a Tecnologia/MCT (Portugal) for the financial support for the QOPNA Research Unit (UID/QUI/00062/2019), LAQV-REQUIMTE (UIDB/50006/2020), CICECO - Aveiro Institute of Materials (UIDB/50011/2020+UIDP/50011/2020), CESAM (UIDB/50017/2020+UIDP/50017/2020) and RNEM (LISBOA-01-0145-FEDER-402-022125), and LEPABE (UIDB/00511/2020) through national founds and, where applicable, co-financed by the FEDER - Fundo Europeu de Desenvolvimento Regional, within the PT2020 Partnership Agreement, and to the Portuguese NMR Network; and the Applied Molecular Biosciences UnitUCIBIO which is financed by national funds from FCT (UIDB/04378/2020). This work was also supported by project grants from FCT (EXPL/BBB-BQB/0750/2012 and PTDC/BIA-MIB/31730/2017), a Biomedical Resource grant from Wellcome Trust (WT099197MA); and FCT individual grants to LMS (SFRH/BD/71455/2010), VGC (PD/BD/105727/2014), ASPM (SFRH/BD/80553/2011), AM (FRH/BPD/75871/2011), FCT researcher positions under the Individual Call to Scientific Employment Stimulus 2007 call to JAF (CEECIND/03186/2017) and to RMF (CEECIND/01854/2017), and FCT Investigator (GN12IF/00033/2012 GN212) to ASP.