Breastfeeding provides many health benefits, but its impact on respiratory health remains unclear. This study addresses the complex and dynamic nature of the mother-milk-infant triad by investigating maternal genomic factors regulating human milk oligosaccharides (HMOs), and their associations with respiratory health among human milk-fed infants. Nineteen HMOs are quantified from 980 mothers of the CHILD Cohort Study. Genome-wide association studies identify HMO-associated loci on chromosome 19p13.3 and 19q13.33 (lowest P = 2.4e-118), spanning several fucosyltransferase (FUT) genes. We identify novel associations on chromosome 3q27.3 for 6\'-sialyllactose (P = 2.2e-9) in the sialyltransferase (ST6GAL1) gene. These, plus additional associations on chromosomes 7q21.32, 7q31.32 and 13q33.3, are replicated in the independent INSPIRE Cohort. Moreover, gene-environment interaction analyses suggest that fucosylated HMOs may modulate overall risk of recurrent wheeze among preschoolers with variable genetic risk scores (P < 0.01). Thus, we report novel genetic factors associated with HMOs, some of which may protect the respiratory health of children.

α1,6-Fucosyltransferase (Fut8) is the enzyme responsible for catalyzing core fucosylation. Exogenous L-fucose upregulates fucosylation levels through the GDP-fucose salvage pathway. This study investigated the relationship between core fucosylation and immunoglobulin G (IgG) amounts in serum utilizing WT (Fut8+/+), Fut8 heterozygous knockout (Fut8+/-), and Fut8 knockout (Fut8-/-) mice. The IgG levels in serum were lower in Fut8+/- and Fut8-/- mice compared with Fut8+/+ mice. Exogenous L-fucose increased IgG levels in Fut8+/- mice, while the ratios of core fucosylated IgG versus total IgG showed no significant difference among Fut8+/+, Fut8+/-, and Fut8+/- mice treated with L-fucose. These ratios were determined by Western blot, lectin blot, and mass spectrometry analysis. Real-time PCR results demonstrated that mRNA levels of IgG Fc and neonatal Fc receptor, responsible for protecting IgG turnover, were similar among Fut8+/+, Fut8+/-, and Fut8+/- mice treated with L-fucose. In contrast, the expression levels of Fc-gamma receptor Ⅳ (FcγRⅣ), mainly expressed on macrophages and neutrophils, were increased in Fut8+/- mice compared to Fut8+/+ mice. The effect was reversed by administrating L-fucose, suggesting that core fucosylation primarily regulates the IgG levels through the Fc-FcγRⅣ degradation pathway. Consistently, IgG internalization and transcytosis were suppressed in FcγRⅣ-knockout cells while enhanced in Fut8-knockout cells. Furthermore, we assessed the expression levels of specific antibodies against ovalbumin and found they were downregulated in Fut8+/- mice, with potential recovery observed with L-fucose administration. These findings confirm that core fucosylation plays a vital role in regulating IgG levels in serum, which may provide insights into a novel mechanism in adaptive immune regulation.

NOTCH1 is a transmembrane receptor interacting with membrane-tethered ligands on opposing cells that mediate the direct cell-cell interaction necessary for many cell fate decisions. Protein O-fucosyltransferase 1 (POFUT1) adds O-fucose to Epidermal Growth Factor (EGF)-like repeats in the NOTCH1 extracellular domain, which is required for trafficking and signaling activation. We previously showed that POFUT1 S162L caused a 90% loss of POFUT1 activity and global developmental defects in a patient; however, the mechanism by which POFUT1 contributes to these symptoms is still unclear. Compared to controls, POFUT1 S162L patient fibroblast cells had an equivalent amount of NOTCH1 on the cell surface but showed a 60% reduction of DLL1 ligand binding and a 70% reduction in JAG1 ligand binding. To determine if the reduction of O-fucose on NOTCH1 in POFUT1 S162L patient fibroblasts was the cause of these effects, we immunopurified endogenous NOTCH1 from control and patient fibroblasts and analyzed O-fucosylation using mass spectral glycoproteomics methods. NOTCH1 EGF8 to EGF12 comprise the ligand binding domain, and O-fucose on EGF8 and EGF12 physically interact with ligands to enhance affinity. Glycoproteomics of NOTCH1 from POFUT1 S162L patient fibroblasts showed WT fucosylation levels at all sites analyzed except for a large decrease at EGF9 and the complete absence of O-fucose at EGF12. Since the loss of O-fucose on EGF12 is known to have significant effects on NOTCH1 activity, this may explain the symptoms observed in the POFUT1 S162L patient.

UNASSIGNED: To determine if the number of vaso-occlusive events in SCD relates to plasma concentration of fucosyltransferase 7 (FUT7), which catalyses the synthesis of selectin ligands.
UNASSIGNED: A prospective, analytical study.
UNASSIGNED: Haematology and Chemical Pathology Departments of tertiary healthcare centres.
UNASSIGNED: Steady state HbSS individuals aged 13-45 years, 20 had 3 or more vaso-occlusive crises that required hospital admission in the previous year (with or without complications of SCD); 17 other HbSS persons had 0-1 vaso-occlusive crisis that required hospital admission in the previous year and no disease complications.
UNASSIGNED: Steady-state plasma concentrations of FUT7 measured by ELISA were compared between SCD patients who had one vaso-occlusive crisis requiring hospital treatment in the previous year but no disease complications and those who had >3 crises with or without complications.
UNASSIGNED: Plasma level of FUT7and the number of vaso-occlusive events in each HbSS patient.
UNASSIGNED: Mean + standard deviation plasma concentration of FUT7 was 8.6 + 2.7 ng/ml in patients with >3 vasoocclusive crises in the previous year and 7.3 + 1.7 ng/ml in those with 0-1 crisis and no complications; independent sample t-test, p > 0.05, not significantly different.
UNASSIGNED: Plasma concentration of fucosyltransferase7 is not associated with the number of vaso-occlusive events in sickle cell disease.
UNASSIGNED: None declared.

This study aimed to determine the function of LINC00511 in Nod-Like Receptor Pyrin Domain 3 inflammasome-mediated chondrocyte pyroptosis via the regulation of miR-9-5p and FUT 1. Chondrocyte inflammatory injury was induced by treating chondrocytes with LPS. Afterwards, the levels of IL-1β and IL-18, the expression of NLRP3, ASC, Caspase-1, and GSDMD, cell viability, and LDH activity in chondrocytes were assessed. LINC00511 expression in LPS-treated chondrocytes was detected, and LINC00511 was subsequently silenced to analyse its role in chondrocyte pyroptosis. The subcellular localization of LINC00511 was predicted and verified. Furthermore, the binding relationships between LINC00511 and miR-9-5p and between miR-9-5p and FUT1 were validated. LINC00511 regulated NLRP3 inflammasome-mediated chondrocyte pyroptosis through the miR-9-5p/FUT1 axis. LPS-treated ATDC5 cells exhibited elevated levels of inflammatory injury; increased levels of NLRP3, ASC, Caspase-1, and GSDMD; reduced cell viability; increased LDH activity; and increased LINC00511 expression, while LINC00511 silencing inhibited the NLRP3 inflammasome to restrict LPS-induced chondrocyte pyroptosis. Next, LINC00511 sponged miR-9-5p, which targeted FUT1. Silencing LINC00511 suppressed FUT1 by upregulating miR-9-5p. Additionally, downregulation of miR-9-5p or overexpression of FUT1 neutralized the suppressive effect of LINC00511 knockdown on LPS-induced chondrocyte pyroptosis. Silencing LINC00511 inhibited the NLRP3 inflammasome to quench Caspase-1-dependent chondrocyte pyroptosis in OA by promoting miR-9-5p and downregulating FUT1.

The FUT2 gene encodes an enzyme called α-1,2-fucosyltransferase, which is involved in the formation of blood group antigens AB0(H) and is also involved in the processes of vitamin B12 absorption and its transport between cells. FUT2 gene polymorphisms are associated with vitamin B12 levels in the body. Vitamin B12 deficiency associated with hyperhomocysteinemia is a major risk factor for cardiovascular diseases (CVDs), which are one of the main causes of death in patients after kidney transplantation. The aim of our study was to determine the impact of the rs602662 (G>A) polymorphism of the FUT2 gene on the functionality of transplanted kidneys and the risk of CVD in patients after kidney transplantation. The study included 402 patients treated with immunosuppression (183 patients taking cyclosporine (CsA) and 219 patients taking tacrolimus (TAC)). The analysis of the FUT2 rs602662 (G>A) polymorphism was performed using real-time PCR. Patients with CsA were more likely to be underweight (1.64% vs. 0.91%) and obese (27.87% vs. 15.98%), while those taking TAC were more likely to be of normal weight (39.27%) or overweight (43.84%). No statistically significant differences were observed comparing the mean blood pressure, both systolic and diastolic. The renal profile showed a higher median urea nitrogen concentration in patients with CsA (26.45 mg/dL (20.60-35.40) vs. 22.95 mg/dL (17.60-33.30), p = 0.004). The observed frequency of rs602662 alleles of the FUT2 gene was similar in the analyzed groups. The A allele was present in 43.7% of patients with CsA and 41.1% of those taking TAC (OR = 0.898; 95% CI: 0.678-1.189; p = 0.453). In the group with CsA, the GG genotype was present in 32.2% of patients, the GA in 48.1% and the AA in 19.7%. A similar distribution was obtained in the TAC group: GG-33.8%, GA-50.2%, and AA-16.0%. An association of genotypes containing the G allele with a higher incidence of hypertension was observed. The G allele was present in 65% of people with hypertension and in 56% of patients with normal blood pressure (p = 0.036). Moreover, the evaluation of the renal parameters showed no effect of the FUT2 polymorphism on the risk of organ rejection because the levels of creatinine, eGFR, potassium, and urea nitrogen were prognostic of successful transplantation. Our results suggest that the rs6022662 FUT2 polymorphism may influence the risk of cardiovascular diseases.

The fucosylation of glycoproteins regulates diverse physiological processes. Inhibitors that can control cellular levels of protein fucosylation have consequently emerged as being of high interest. One area where inhibitors of fucosylation have gained significant attention is in the production of afucosylated antibodies, which exhibit superior antibody-dependent cell cytotoxicity as compared to their fucosylated counterparts. Here, we describe β-carbafucose, a fucose derivative in which the endocyclic ring oxygen is replaced by a methylene group, and show that it acts as a potent metabolic inhibitor within cells to antagonize protein fucosylation. β-carbafucose is assimilated by the fucose salvage pathway to form GDP-carbafucose which, due to its being unable to form the oxocarbenium ion-like transition states used by fucosyltransferases, is an incompetent substrate for these enzymes. β-carbafucose treatment of a CHO cell line used for high-level production of the therapeutic antibody Herceptin leads to dose-dependent reductions in core fucosylation without affecting cell growth or antibody production. Mass spectrometry analyses of the intact antibody and N-glycans show that β-carbafucose is not incorporated into the antibody N-glycans at detectable levels. We expect that β-carbafucose will serve as a useful research tool for the community and may find immediate application for the rapid production of afucosylated antibodies for therapeutic purposes.

OBJECTIVE: The immunosuppressive tumor microenvironment (TME) plays an essential role in cancer progression and immunotherapy response. Despite the considerable advancements in cancer immunotherapy, the limited response to immune checkpoint blockade (ICB) therapies in patients with hepatocellular carcinoma (HCC) remains a major challenge for its clinical implications. Here, we investigated the molecular basis of the protein O-fucosyltransferase 1 (POFUT1) that drives HCC immune evasion and explored a potential therapeutic strategy for enhancing ICB efficacy.
METHODS: De novo MYC/Trp53-/- liver tumor and the xenograft tumor models were used to evaluate the function of POFUT1 in immune evasion. Biochemical assays were performed to elucidate the underlying mechanism of POFUT1-mediated immune evasion.
RESULTS: We identified POFUT1 as a crucial promoter of immune evasion in liver cancer. Notably, POFUT1 promoted HCC progression and inhibited T-cell infiltration in the xenograft tumor and de novo MYC/Trp53-/- mouse liver tumor models. Mechanistically, we demonstrated that POFUT1 stabilized programmed death ligand 1 (PD-L1) protein by preventing tripartite motif containing 21-mediated PD-L1 ubiquitination and degradation independently of its protein-O-fucosyltransferase activity. In addition, we further demonstrated that PD-L1 was required for the tumor-promoting and immune evasion effects of POFUT1 in HCC. Importantly, inhibition of POFUT1 could synergize with anti-programmed death receptor 1 therapy by remodeling TME in the xenograft tumor mouse model. Clinically, POFUT1 high expression displayed a lower response rate and worse clinical outcome to ICB therapies.
CONCLUSIONS: Our findings demonstrate that POFUT1 functions as a novel regulator of tumor immune evasion and inhibition of POFUT1 may be a potential therapeutic strategy to enhance the efficacy of immune therapy in HCC.

Probiotics have gained significant attention as a potential strategy to improve health by modulating host-microbe interactions, particularly in situations where the normal microbiota has been disrupted. However, evidence regarding their efficacy has been inconsistent, with considerable interindividual variability in response. We aimed to explore whether a common genetic variant that affects the production of mucosal α(1,2)-fucosylated glycans, present in around 20% of the population, could explain the observed interpersonal differences in the persistence of commonly used probiotics. Using a mouse model with varying α(1,2)-fucosylated glycans secretion (Fut2WT or Fut2KO), we examined the abundance and persistence of Bifidobacterium strains (infantis, breve, and bifidum). We observed significant differences in baseline gut microbiota characteristics between Fut2WT and Fut2KO littermates, with Fut2WT mice exhibiting enrichment of species able to utilize α(1,2)-fucosylated glycans. Following antibiotic exposure, only Fut2WT animals showed persistent engraftment of Bifidobacterium infantis, a strain able to internalize α(1,2)-fucosylated glycans, whereas B. breve and B. bifidum, which cannot internalize α(1,2)-fucosylated glycans, did not exhibit this difference. In mice with an intact commensal microbiota, the relationship between secretor status and B. infantis persistence was reversed, with Fut2KO animals showing greater persistence compared to Fut2WT. Our findings suggest that the interplay between a common genetic variation and antibiotic exposure plays a crucial role in determining the dynamics of B. infantis in the recipient gut, which could potentially contribute to the observed variation in response to this commonly used probiotic species.

Long since, carbohydrates were thought to be used just as an energy source and structural material. However, in recent years, with the emergence of the field of glycobiology and advances in glycomics, much has been learned about the biological role of oligosaccharides, a carbohydrate polymer containing a small number of monosaccharides, in cell-cell interaction, signal transduction, immune response, pathogen adhesion processes, early embryogenesis, and apoptosis. The function of oligosaccharides in these processes is diversified by fucosylation, also known as modification of oligosaccharides. Fucosylation has allowed the identification of more than 100 different oligosaccharide structures that provide functional diversity. ABO blood group and Lewis antigens are among the best known fucosyl-linked oligosaccharides. In addition, the antigens in the ABO system are composed of various sugar molecules, including fucosylated oligosaccharides, and Lewis antigens are structurally similar to ABO antigens but differ in the linkage of sugars. Variation in blood group antigen expression affects the host\'s susceptibility to many infections. However, altered expression of ABO and Lewis antigens is related with prognosis in carcinoma types. In addition, many pathogens recognize and bind to human tissues using a protein receptor with high affinity for the fucose molecule in glycoconjugates, such as lectin. Fucosylated oligosaccharides also play vital roles during fertilization and early embryogenesis. Learning and memory-related processes such as neurite growth, neurite migration, and synapse formation seen during the development of the brain, which is among the first organs to develop in embryogenesis, are regulated by fucosylated oligosaccharides. In conclusion, this review mentions the vital roles of fucosylated oligosaccharides in biology, drawing attention to their importance in the development of chemical tools to be used in function analysis and the investigation of various therapeutic targets.