Fig 2: Association of Siglec ligands with fibrosis. A. Representative images from a TN tumor of Siglec-7, Siglec-9, and Siglec-10 staining in low and high fibrosis regions. Scale bar is 100 μm. B. Quantification of median intensity within Siglec ligand-positive regions for Siglec-7-Fc, Siglec-9-Fc, and Siglec-10-Fc.

Fig 3: sia-rDer p 2 binds to Siglec-9 and/or Siglec-10 expressed on APCs. A, Schematic representation of the thiol-malemide reaction for the conjugation of α2-3 sialic acids to rDer p 2. B, Representative histograms showing the binding of rDer p 2 and sia-rDer p 2 on classical monocytes (CD14+CD16+), CD11c+ DCs, and B cells. C, The percentage of cells among monocytes, CD11c+ DCs, and B cells that bound polyacrylamide-α2-3 (positive control [PC]), rDer p 2, and sia-rDer p 2 (n = 3). Data are shown as mean ± SD. D, Representative histograms showing the expression of Siglec-9 on classical monocytes after incubation of cells with either rDer p 2 or sia-rDer p 2.

Fig 4: Differential binding to inhibitory lectins by bacteria associated with term and preterm birth.Bacteria (106 per well) were coated in 96-well plates and tested for their capacity to bind Siglec 9-Fc (a), Siglec 10-Fc (b) and DC-SIGN-Fc (c). Lje L. jensenii, Ljo L. johnsonii, Lv Limosilactobacillus vaginalis, Lg L. gasseri. Data are mean +/−SD (n = 3 biological replicates). One way ANOVA, Dunnett multiple comparison test against control (PBS) condition. *p < 0.05, **p < 0.01, ***p < 0.005, ****p < 0.001. Source data are provided as a Source Data file.

Fig 5: Design of DGlyTAC nbGFP-PNGF for protein-specific de-N-glycosylation on eGFP-CD24. Western blot analyzed the effect on the expression and glycosylation of eGFP-CD24 which overexpression on CHO cell lines after the treatment of different concentrations of PNGF (a), nbGFP-PNGF (b), and nbGFP-PNGF-E206K (c) for 2 h. (d) eGFP-CD24 was enriched by anti-eGFP beads and analyzed by immunoblotting to reveal protein levels (anti-GFP) and N-glycosylation level (ConA). CHO-CD24 whole cell lysate (WCL) was treated with 1 μM PNGF (as positive control, PC), PBS (as nagative control, NC), 0.05 nM PNGF, nbGFP-PNGF, and nbGFP-PNGF-E206K for 24 h, we proceeded with the labeling of N-glycans using ConA-Biotin. (e) Quantitation of N-glycosylation level on eGFP-CD24 calculated from (d). (The box and error bars represent the mean ± SEM. Independent experiment = 3, and a representative data was shown; ‘NS’ means not significant; ‘*’ means p < 0.05; ‘**’ means p < 0.01; ‘***’ means p < 0.001) (f, g) Change of eGFP-CD24 protein level via treatment from 5 nM PNGF and nbGFP-PNGF at different time points. h Immunoblotting of eGFP-CD24 resulted from cells exposed to low concentrations of nbGFP-PNGF for 24 h. i, k Treated CHO-CD24 with or without 50 µM sialyltransferase inhibitor P-3Fax-Neu5Ac (deleting sialic acids on CHO-CD24), then incubated with 5 nM PNGF and nbGFP-PNGF for 2 hours, and flow cytometry measuring Siglec-10 binding on the membrane of eGFP-CD24. j, l Quantitation of the CD24/Siglec-10 binding from i and k, respectively. The relative values are results divided by blank. (The box and error bars represent the mean ± SEM. Independent experiment = 3, and a representative data was shown; ‘NS’ means not significant; ‘*’ means p < 0.05; ‘**’ means p < 0.01; ‘***’ means p < 0.001) m, n Assessment about the contributions of sialyl modification and N/O-glycosylation on CD24/Siglec-10 interaction in the CHO-CD24 cells analyzed from (j, l)