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![Page 1: Carbohydrate microarrays for the recognition of cross-reactive molecular markers of microbes and host cells Denong Wang et al Presented by Chao Ji.](https://reader036.fdocuments.us/reader036/viewer/2022062713/56649f4f5503460f94c719df/html5/thumbnails/1.jpg)
Carbohydrate microarrays for the recognition of cross-reactive molecular markers of microbes
and host cells
Denong Wang et alPresented by Chao Ji
![Page 2: Carbohydrate microarrays for the recognition of cross-reactive molecular markers of microbes and host cells Denong Wang et al Presented by Chao Ji.](https://reader036.fdocuments.us/reader036/viewer/2022062713/56649f4f5503460f94c719df/html5/thumbnails/2.jpg)
• Carbohydrates play important role in microbe-host interaction (e.g. many epitopes are carbohydrates)
• A carbohydrate-based microarray system sensitive enough to be able to detect a wide range of antibodies specificities
• Is it feasible and good enough?– Whether carbohydrates can be immobilized on a glass
surface without covalent bond– Whether immobilized carbohydrates preserve their
immunological properties– Whether the proposed system reaches the sensitivity and
capacity to detect a broad range of antibody specificities using only small quantities of sample
– Whether it can be used to study carbohydrate interactions with high throughput
![Page 3: Carbohydrate microarrays for the recognition of cross-reactive molecular markers of microbes and host cells Denong Wang et al Presented by Chao Ji.](https://reader036.fdocuments.us/reader036/viewer/2022062713/56649f4f5503460f94c719df/html5/thumbnails/3.jpg)
• Structure of Dextran– Polymerization of glucose– Linear: α(1,6)– Branched:α(1,6), α(1,3) or α(1,2)– Representative of a variety of types of sugars– Recognizable by antibodies with different epitope specificity– Model system to immobilize carbohydrate antigens and study
their immunological property
![Page 4: Carbohydrate microarrays for the recognition of cross-reactive molecular markers of microbes and host cells Denong Wang et al Presented by Chao Ji.](https://reader036.fdocuments.us/reader036/viewer/2022062713/56649f4f5503460f94c719df/html5/thumbnails/4.jpg)
• Nitrocellulose-coated glass slides can be used to immobilize carbohydrates without covalent bonds– FITC-conjugated dextrans of different MW and insulin were printed
on slides– Dextran with MW 20kDa-2,000kDa stably immobilized non-covalently– Larger dextran molecules were better retained
![Page 5: Carbohydrate microarrays for the recognition of cross-reactive molecular markers of microbes and host cells Denong Wang et al Presented by Chao Ji.](https://reader036.fdocuments.us/reader036/viewer/2022062713/56649f4f5503460f94c719df/html5/thumbnails/5.jpg)
• Immunological properties of dextrans are well-preserved when immobilized on nitrocellulose coated slides– Carbohydrate antigens: N279, both internal linear and
terminal non-reducing end; B1299S, heavily branched; LD7, 100% internal linear
– Antibodies: IgG3(4.3F1), groove-type, targets internal linear α(1,6) chain; IgA(16.4.12E), cavity-type targets terminal non-reducing end strucuture
![Page 6: Carbohydrate microarrays for the recognition of cross-reactive molecular markers of microbes and host cells Denong Wang et al Presented by Chao Ji.](https://reader036.fdocuments.us/reader036/viewer/2022062713/56649f4f5503460f94c719df/html5/thumbnails/6.jpg)
• The carbohydrate arrays is sensitive enough for the detection of a broad spectrum of antibody specificities – 48 structurally distinct carbohydrate-containing
macromolecules– 20 serum specimens, 1μl from each for staining– 12/48 specificities of IgM and 35/48 of IgG – A speculation based on IgG > IgM: naturally occurring anti-
carbohydrate antibodies may be of IgG type
![Page 7: Carbohydrate microarrays for the recognition of cross-reactive molecular markers of microbes and host cells Denong Wang et al Presented by Chao Ji.](https://reader036.fdocuments.us/reader036/viewer/2022062713/56649f4f5503460f94c719df/html5/thumbnails/7.jpg)
4 Classes1 polysaccharide: 292 glycosaminoglycan: 33 glycoprotein: 114 semisynthetic glycoconjugate: 5
![Page 8: Carbohydrate microarrays for the recognition of cross-reactive molecular markers of microbes and host cells Denong Wang et al Presented by Chao Ji.](https://reader036.fdocuments.us/reader036/viewer/2022062713/56649f4f5503460f94c719df/html5/thumbnails/8.jpg)
• Characterizing previously unnkown specificity and cross-reactivity of carbohydrate/antibody interaction– 2 anti-dextran mAbs: 4.3.F1 and 16.4.12E applied on the same panel of
carbohydrate– CS-B is recognized by 4.3.F1 (unexpectedly) because of its non-dominant
structure rather than its dominant repeating disaccharide sequence of GalNAc(4S)
– In vivo study showed the structure recognized by 4.3F1 is an endogenous cellular element
– 4.3F1 staining is resistant to the pretreatment of tissue by dextranase– 45.21.1: another anti α(1-6) groove-type antibody that also reacted with CS-B
4.3.F1 16.4.12E
BSA(E1),KLM(E2) N Y
CS-B(A6) Y N
![Page 9: Carbohydrate microarrays for the recognition of cross-reactive molecular markers of microbes and host cells Denong Wang et al Presented by Chao Ji.](https://reader036.fdocuments.us/reader036/viewer/2022062713/56649f4f5503460f94c719df/html5/thumbnails/9.jpg)
Conclusion
• A sensitive and efficient carbohydrate microarray with large capacity
• Only small quantity of specimen is necessary in the detection of antibody specificities
• Broad applicability in a wide range of biomedical research involving carbohydrate-based molecular recognition