Ingrid 't Hart

33 Chemoenzyma�c synthesis of DSGb5 2 Figure 2. Microarray results of the synthe�c compounds with ( A ) MAL-II, ( B ) SBA, ( C ) WGA, ( D ) an�-GM1 and ( E ) Siglec-7. C indicates buffer control. Bars represent the mean ± SD. Although no binding was observed on the glycan microarray, it cannot be excluded that the ceramide moiety of DSGb5 can modulate Siglec-7 binding by organizing it into microdomains for low-affinity high-avidity mul�valent interac�ons. 31 Therefore, our future studies will focus on the prepara�on of DSGb5 having a ceramide moiety for binding and cellular ac�va�on studies. Such a compound will also be valuable to explore other cellular roles of DSGb5 such as promo�ng tumor cell migra�on. 32 Furthermore, a very recent study, employing a library of isogenic HEK293 cells with combinatorially engineered glycosyla�on capaci�es, indicated that Siglec-7 recognizes core 2 O -glycans having α2,3 and 2,6-linked sialosides which will also be an important target for future synthesis. 33 It is clear that the ability of glycans having an internal α2,6-sialoside at GlcNAc and GalNAc to mediate cellular ac�va�on in Siglec-7 dependent manner needs further inves�ga�on. 4b (Gb5) 6b (DSGb5) 5b (MSGb5) 18 (GM2) 21 (GT1b) 19 (GM1a) 20 (GD3) 17 (GM3)