Supplementary Material

The glycobiology of the CD system: a dictionary for translating marker

designations into glycan/lectin structure and function

Hans-Joachim Gabius1, Herbert Kaltner1, Jürgen Kopitz2, and Sabine André1

1Institute of Physiological Chemistry, Faculty of Veterinary Medicine, Ludwig-

Maximilians-Universität München, Veterinärstr. 13, 80539 Munich, Germany2Institute for Pathology, Department of Applied Tumor Biology, Ruprecht-Karls-

University, Im Neuenheimer Feld 224, 69120 Heidelberg, Germany

Tel. +49-(0)89-2180 2290

FAX: +49-(0)89-2180 992290

e-mail: gabius@tiph.vetmed.uni-muenchen.de or gabius@lectins.de

CD11b

This integrin subunit (M) is structurally composed of three sections (Figure 2): the

inserted (I) domain (a module prominently acting in contact building to extracellular

matrix glycoproteins, the intercellular adhesion molecules (ICAMs)-1/-2, fibrinogen, the

platelet glycoprotein GPIb or the opsonic complement component inactivated (i)C3b),

a region binding divalent cations and the lectin-like domain (proximal to the membrane)

specific for -N-acetylglucosamine residues presented by N-glycans or for -glucans

[S1]. In complex with CD18 (2-integrin), CD11b forms the leukocyte complement

receptor 3 (or Mac-1 antigen). Engagement of its lectin activity let the integrin become a

sensor for iC3b-coated cells and an effector for platelet clearance. Among its binding

partners, also called counterreceptors, is CD23.

CD23

This type II transmembrane glycoprotein of about 45 kDa with a C-type CRD is a low-

affinity IgE receptor (FcRII). Lectin activity is attributed to this CRD, and the localization

of its gene in a cluster with other sequences of C-type lectins such as CD209 (please see

below) indicates its origin by gene divergence [S2, S3]. Extracellularly, the CRD is

connected with a stalk region for oligomerization so that the distal lectin sites can form

clusters (Figure 2). Key interaction partners are IgE, CD21 and CD11b/CD18. Capacity

for signaling leading to pro-inflammatory cytokine responses allows cell surface-

1

presented and soluble (after ADAM10-dependent cleavage) CD23 to be classified as an

immune regulator.

CD31

The platelet endothelial cell adhesion molecule-1 (PECAM-1) belongs to the Ig

superfamily with its six extracellular C2-type domains. These versatile modules afford

the structural basis for homophilic and also for heterophilic interactions with proteins

such as CD38 (ADP-ribosyl cyclase). The C2-type domains are followed by the

transmembrane section and the cytoplasmic tail (118 amino acids) [S4, S5]. That each

domain has distinct features broadens the spectrum of in situ binding partners to

include glycosaminoglycans. In detail, whereas homophilic events critically depend on

Ig-like domain 1, high-affinity binding sites for heparin/heparan sulfate are located in

Ig-like domains 2 and 3 [S6].

CD44

This rather ubiquitous type I transmembrane glycoprotein is known for its occurrence

in a wide variety of isoforms through alternative splicing. A single link module at the N-

terminus (residues 32-124), also called a link protein homology region, conveys binding

capacity to hyaluronic acid to CD44 isoforms, as it does for the hyaladherins LYVE-1 and

the product of tumor necrosis factor--stimulated gene-6 (TSG-6), for the hyaluronan

receptor for endocytosis (HARE) and the extracellular matrix glycoproteins aggrecan,

brevican, neurocan and versican, which are also known as lecticans due to the presence

of a C-type CRD [S7, S8].

CD56

The neural cell adhesion molecule-1 (NCAM-1), another member of the Ig superfamily, is

encoded by a single gene and, like CD44, present in many (up to 30) isoforms due to

ensuing processing. The molecular weights and mode of membrane anchoring can differ

among isoforms. Its extracellular region is composed of five Ig-like C2-type domains

(two stacked -sheets cross-linked by a disulfide bond) and two fibronectin type III-like

modules, which are proximal to the membrane [S9, S10]. Typical features of its N-

glycosylation are the presence of 2,8-linked polysialic acid, oligomannosidic structures

and the HNK-1 epitope (CD57, Figure 1) [S9, S10]. As noted for CD31, individual Ig-like

modules have acquired particular binding properties: the fourth Ig-like domain can

2

accommodate oligomannosidic glycans, and the second module binds heparan sulfates

[S11].

CD62E,L,P

That lymphocytes from distinct lymphoid sites were able to find their way back to their

original home after re-injection into animals was interpreted as evidence for tissue-

specific adhesion mechanisms [S12]. As outlined in the introductory section, monoclonal

antibodies against three different cell surface glycoproteins were crucial for the

identification of the protein side of the assumed recognition. The three selectins, present

in endothelial (E) cells, lymphocytes (L) or platelets (P), share the modular display with

the N-terminal C-type CRD followed by an epidermal growth factor (EGF)-like domain,

two (CD62L) to nine (CD62P) short consensus repeats known from complement-

regulatory proteins (also called sushi domain), then completed by the about 25-amino-

acid-long transmembrane section and the C-terminal cytoplasmic tail (Figure 2) [S13].

Summarizing this domain composition, the descriptive term LEC-CAM (Lectin-Egf-

Complement Cell Adhesion Molecule) had been used synonymously. CD15s (Figure 1) is

among the pan-selectin binders; the glycan-lectin association is driven by the entropic

gain (TS: 23 kJ mol-1) [S14, S15]. Preformed complementarity between the contact

surfaces leading to directional polar interactions accounts for a fast on-rate (>106 M-1s-1)

in selectin binding, which is essential to allow anchoring of cells flowing by in the blood

[S16]. Tyrosine sulfation can serve as non-glycan part of the docking site, e.g. in P-

selectin glycoprotein ligand-1 (PSGL-1) (Tys7/Tys10) [S16] or the glycoprotein T cell

immunoglobulin and mucin domain 1 (TIM-1) [S17]. Of interest, TIM-1 recognition by

CD62E,P is operative without sialylation, which is a key determinant in binding PSGL-1

or CD44 [S17]. In addition to acting as a natural braking system to slow down leukocytes

on an endothelial surface, the selectin (CD62)-counterreceptor recognition underlies the

phenomenon of rolling of cells by formation of catch bonds. Their lifetime increases

under shear stress, likely involving re-orientation of the C-type CRD against the EGF-like

domain *33[S18]. The selectin-dependent phase is the prerequisite for the transition

from rolling to firm adhesion mediated by integrins.

3

CD94

This antigen is expressed on NK cells. Activating receptors can make NK cells prone to

also attack self targets, leading to auto-aggression. In order to counterbalance respective

signaling, inhibitory mechanisms have developed based on three receptor classes.

Among MHC class I receptors, the C-type lectin CD94 becomes disulfide bridged to a

signaling companion of the NKG2 family, building a heterodimer (Figure 2). NKG2 genes,

coding for type II transmembrane proteins with an extracellular C-type lectin-like

domain, belong to the NK complex on the short arm of human chromosome 12 [S19,

S20]. Having first (expectedly) been detected by monoclonal antibodies [S21], CD94 is

now that the presence of the CRD is known referred to as another member of the family

of C-type lectins. Its own cytoplasmic portion is restricted in length to only seven amino

acids [S22]. Consequently, CD94 makes use of the signaling motif of the NKG2 protein (A,

B, C, E or H). Association with NKG2A/B brings their consensus ITIM (Immunoreceptor

Tyrosine-based Inhibitory Motif) sequence into the complex, engendering the negative

effect on NK cell activity (please see CD170 and CD328 for the role of ITIMs in siglecs).

Attesting to its physiological role, antibody blocking of CD94 reduced NK cell-mediated

cytotoxicity against human melanoma cells with a high-level sialyl Lex (CD15s)

presentation, as did a neoglycoconjugate with this epitope (inert carrier with custom-

made chemical glycosylation as bioactive part [S23]). These experiments provided first

information of CD94’s lectin activity [S24]. Tri- and tetraantennary N-glycans with 2,3-

sialylation (of the human 1-acid glycoprotein) and heparin (conjugated to bovine serum

albumin) were later described to bind to a fusion protein with the C-type lectin CRD of

CD94 as sensor, as they did to similarly engineered NKG2D [S25, S26].

CD141

Thrombomodulin is a predominantly endothelial glycoprotein that has anticoagulant

activity, through inhibition of the pro-coagulant thrombin and by serving as cofactor for

thrombin-catalyzed activation of the anti-coagulant protein C [S27]. It controls multiple

biological processes in inflammation and vascular integrity, therefore looking at its

modular design is a step toward unraveling structure-activity relationships: following a

short cytoplasmic tail and the transmembrane region, the extracellular portion

comprises a serine/threonine-rich section with a chondroitin sulfate chain (relevant for

anticoagulation; for further information on glycosaminoglycans/proteoglycans, please

see [S7, S28]), six EGF-like repeats, a hydrophobic region and the C-type CRD (Figure 2).

4

The lectin module is a receptor for Ley determinants (CD174, Figure 1) on

lipopolysaccharide, connected to CD141’s activity to confine tissue damage, and on

cellular glycoproteins such as the EGF receptor, to block its angiogenic activity [S29,

S30].

CD169

This 185-kDa member of the Ig-like family (a type I transmembrane glycoprotein with

its CRD in the distal V-set Ig-like domain followed by 16 extracellular C2-type modules

to give the CRD excellent spatial accessibility, Figure 2) was the first Ig-like receptor

found to have binding specificity for sialylated glycans. It was thus termed siglec (sialic

acid-binding Ig-like lectin). Its original name ‘sheep erythrocyte receptor’ was based on

results of experiments studying adhesion activities on resident bone marrow

macrophages, whose association to unopsonized erythrocytes was reduced by 3’-

sialyllactose and ganglioside GD1a [S31]. The SER-4 blocking antibody, raised against

murine serum-induced peritoneal macrophages, was applied in affinity

chromatography. This method facilitated the purification of the lectin (now named

sialoadhesin or siglec-1), which is known to be a marker for macrophages in transition

regions. Siglec-1 has affinity to 2,3-sialylated Thomsen-Friedenreich (TF) disaccharide

(CD176s) in sialoglycoproteins (human glycophorin) and to the glycan chains of certain

gangliosides (GT1b, GD1a and GM3) [S32]. The exceptionally long length of its

extracellular section (17 Ig-like domains compared to two to seven in other siglecs)

makes it ideally suited for trans-interactions. A preferential role of siglec-1 as an active

player in mediating interactions with other cells is further supported by the absence of

an intracellular ITIM or any other tyrosine-harboring putative signaling motif. Siglec-1

can bridge lymphocytes/tumor cells and macrophages, via recognition of sialomucins

leukosialin (CD43) on T cells or MUC-1 on breast cancer cells, as glycans of the siglec, in

addition, become sites for associating cells by a C-type macrophage lectin (CD301) or by

CD206. Of note, surface epitopes of human pathogens, i.e. sialylated lipooligosaccharides

from Campylobacter jejuni and Neisseria meningitidis, are targets of siglec-1 in host

defence [S33, S34] (for information on bacterial glycosylation, please see [S35]). On the

chromosomal level, the genes for human and murine siglec-1 are not part of the gene

cluster for the reminder of the siglec family on human chromosome 19q or mouse

chromosome 7 but located on chromosomes 20 (human) or 2 (mouse) [S36].

5

CD170

Siglec-5 was the first member of this lectin family to be tracked down by a

computational homology search, using the CD33 (siglec-3) sequence and a database

containing more than one million expressed sequence tags [S37]. It contains one V-set

and three C2-set Ig-like domains that have specificity toward sialic acid irrespective of

its linkage to the rest of the glycan. As for all eight human CD33-related siglecs, CD170

has a membrane-proximal ITIM sequence and a distal ITIM-like motif in its cytoplasmic

tail. Tyrosine phosphorylation recruits the protein-tyrosine phosphatases SHP-1/-2

(two Src homology (SH)-1/-2 domain-containing enzymes) for inhibitory signaling

[S38]. Despite its initial classification as OB-BP2 (binding protein for the product of the

putative obesity gene, which codes for leptin, causing extreme obesity) its low level of

reactivity was considered “unlikely to be physiologically relevant” [S39]. Expression was

detected in granulocytes and B lymphocytes, its paired activating receptor siglec-14, a

product of concerted evolution, is present on monocytes instead of B cells, illustrating

that there can be unique features even between very closely related family members

[S40]. Special among siglecs, it is engaged in a protein-dependent (sialic acid-

independent) interaction with the cell wall-anchored protein of group B Streptococcus,

which subverts the ITIM-based signaling of siglec-5 to dampen innate defense reactions

[S41].

CD206

The macrophage (tandem-repeat-type) mannose receptor was first detected as

endocytic entry site for glycoproteins with mannose/N-acetylglucosamine-terminated

N-glycans on rat Kupffer cells [S42] (for further information on N-glycosylation, please

see [S9, S43]), later targeted with clinical benefit in enzyme replacement therapy [S44].

Its modular design as type I transmembrane glycoprotein is composed of a cysteine-rich

(-trefoil) domain, a fibronectin type II module with collagen (I-IV) reactivity, eight C-

type lectin/lectin-like domains and the cytoplasmic tail with signals for delivery to and

recycling from early endosomes (Figure 2) [S45, S46]. As lectin, CD206 is thus

bifunctional via two structurally different sites: CRD no. 4 binds mannose, N-

acetylglucosamine and fucose, the segment of domains 4-8 is reactive with multivalent

sugar ligands, and the -trefoil domain has affinity for SO4-4-GalNAc1,4GlcNAc

termini of N-glycans of glycoprotein hormones [S47]. This capacity for glycan binding

through two structurally distinct sites is unique within the group of the four mammalian

6

endocytic receptors of this type (not shared by the M-type phospholipase A2 receptor,

urokinase-type plasminogen activator receptor-associated protein Endo180 (CD280;

discussed later) and the dendritic cell receptor DEC205 (CD205)). To give examples of

glycan ligands, cell-specific glycoforms of CD45 and CD169 are reactive with the -trefoil

domain. As ligand for a lectin, glycans of CD206 appear to associate with CD62L so that

contact of lymphocytes and lymphatic endothelium is mediated. Hereby, a role in

immune cell trafficking is added to the lectin’s activity for efficient glycoprotein

endocytosis, with participation also in antigen presentation [S48, S49].

CD207

Langerin is so named because the detecting monoclonal antibody (DCGM4) selectively

stained (via this 40 kDa antigen) Langerhans cells, a subset of dendritic cells residing in

skin epidermis and mucosal epithelium, [S50]. Like CD206, albeit type II, it is a

glycoprotein that is active as endocytic receptor, but it has only one C-type CRD, not a

tandem-repeat display (Figure 2). Binding to oligovalent ligands is made possible by an

extracellular neck region for trimerization stabilized by a coiled-coil of -helices as in

CD23. Uniquely for a C-type lectin with the mannose-binding tripeptide motif (Glu-Pro-

Asn), its CRD can also accommodate 6-sulfated galactose (e.g. the terminal sugar in the

glycosaminoglycan keratan sulfate) [S51]. Single nucleotide polymorphisms in the CRD

(K313I, N288D) act as an off switch for this specificity, a case of a direct effect of single-

site mutations on glycan binding [S52]. Alternatively, long-range consequences of such

sequence alterations are known to occur, e.g. in a lectin of a different family [S53]. In

addition, Ca2+-independent binding of heparan-sulfate-type glycosaminoglycans at the

trimeric neck region (involving Arg187) has been reported [S54]. Its endocytic capacity,

relevant for formation of Birbeck granules typical for Langerhans cells, and its reactivity

to fungal surfaces resemble the activity profile of related C-type lectins on dendritic cells

and macrophages. Thus, a group of cooperating C-type lectins, to which the next lectin

discussed (CD209) belongs, have distinct glycan-binding features to cover a broad range

of pathogenic glycan signatures [S55, S56].

CD209

The genes for this dendritic C-type lectin and the closely related liver/lymph node-

specific CD209L/CD299 (also called DC-SIGNR- or L-SIGN; please see below) are part of

a cluster on chromosome 19p13.3, along with the gene for CD23 [S57]. It was originally

7

detected as contact partner for the glycoprotein gp120 of the human immunodeficiency

virus by expression cloning using a placental cDNA library [S58], Later, it was shown to

connect resting T cells that present ICAM-3 to dendritic cells, explaining its name as

dendritic cell-specific ICAM-3-grabbing non-integrin (DC-SIGN) [S59]. The 44 kDa

glycoprotein is a type II transmembrane receptor with a 40-amino-acid intracellular

section harboring at least three intracellular sorting motifs, a neck for tetramer

formation and the C-type CRD (Figure 2). The CRD has affinity for mannose and for Le

epitopes (similar to CD207), the further affinity for Ley (CD174) shared by CD141 [S60,

S61]. The lectin is found in immature (periphery) and mature (lymphoid sites) dendritic

cells (but not plasmacytoid/follicular dendritic cells) and macrophages (M2, CD14+). In

addition to roles in cell adhesion and antigen presentation, DC-SIGN helps shape

immune responses as the pathogen sensor of a signalosome (containing the three

scaffold proteins LPS-1, KSR-1 and DNK and the kinase Raf-1) [S62] (for comment on

relevance of elucidating in vivo functions in murine knock-out models, please see section

on CD299). Acting as docking site for viral glycans, CD209 counterintuitively promotes

infection (as similarly seen for CD169, CD206, CD294, CD301-303: for recent review,

please see [S63]), a clinically relevant lesson in how a defence line can be exploited by

viral glycosylation.

CD222

The Ca2+-independent lectin property of this 300 kDa dimeric type I transmembrane

glycoprotein is assigned to a domain that is reactive with mannose-6-phosphate, thus it

is referred to as P-type CRD. The unusual ability to bind phosphomannosyl residues,

which is shared only by a second (cation-dependent) lectin, was delineated from studies

on fibroblasts of patients with the lysosomal storage disorder mucolipidosis-II, together

with the discovery that this type of sugar is a marker (routing signal) for lysosomal

enzymes [S64]. Sequence alignments later uncovered homologies to three proteins in

the endoplasmic reticulum (erlectin (XTP3-B), OS-9 (upregulated in osteosarcomas) and

the 55 kDa non-catalytic -subunit of -glucosidase-II) as well as the -subunit of the

Golgi GlcNAc-phosphotransferase. As consequence, the P-type CRD is now a part of the

mannose-6-phosphate receptor homology (MRH) family. This CRD present in two P-type

lectins is responsible for uptake of cognate glycoproteins and their intracellular

trafficking [S65]. Similar to CD206, its extracellular domains, here a total of 15, are

arranged in a tandem-repeat orientation (Figure 2). Carbohydrate binding was localized

8

to two high-affinity sites at domains 3 and 9 [S64]. Of note, domain 11 interacts with

insulin-like growth factor type 2 (IGF-2) [S64]. Thus, the receptor exhibits a dual

functionality to bind sugar and protein at different domains, and is thus referred to as P-

type lectin/IGF-2 receptor. Also, plasminogen, the precursor of the central enzyme of

fibrinolysis, interacts with domain 1, of potential relevance for its conversion to the

active serine protease plasmin, and retinoic acid is also a non-glycan binding partner

[S64]. Obviously, the P-type domain is subject to diversification with respect to

molecular interactions beyond sugars, as seen above for C- and I-type lectins. Three

separate internalization sequences guide the lectin’s intracellular routing. Loss of

heterozygosity at the locus of this gene occurs in human cancer, pointing to a role of a

deficiency in this receptor for enhancement of tumorigenicity in established tumor cells

[S66].

CD280

The quest to identify new members of the C-type lectin family led Wu et al. [S67] to

search the expressed sequence tag cDNA data base for homologues of the sequence

motif for the CRD of CD62E. Although the sequence hit only reached a degree of “low

homology (~ 23 %)” in total, it had the same amino acids at positions that are conserved

among C-type lectins, and cloning yielded a sequence with a remarkable degree of

identity (32.5-34%) to the known members of the mannose receptor (CD206) family

[S67]. Independently, CD280, at that time referred to as glycoprotein (p180), had been

described as constitutively recycling surface antigen (Endo180) in human fibroblasts

[S68] and as urokinase plasminogen activator receptor-associated protein (uPARAP)

[S69]. Similar to CD206, Endo180 is also a collagen receptor via its fibronectin type II

region; in contrast to CD206, the cysteine-rich domain is not a lectin. Besides the

common protein-collagen contact, the second C-type lectin domain of this receptor is

also capable of interacting with O-glycosylated collagen, which CD206 cannot do [S70].

The nearly complete abrogation of collagen endocytosis, diminished initial adhesion to

collagens and impaired migration of murine fibroblasts deficient in this receptor

intimate CD280’s importance for cellular collagen interactions [S71].

9

CD299

The sinusoidal endothelial cell receptor DC-SIGNR (L-SIGN, CD209L) shares its modular

display with the dendritic cell DC-SIGN (CD209), with 77 % amino acid sequence

identity (Figure 2). Two features, besides the cellular expression profile, appear

different by comparison: i) Val 351 in DC-SIGN, which creates a hydrophobic pocket for

accommodating 1,3/4-fucosylated Le epitopes and building van der Waals contacts

with the 2’-OH group of fucose, is substituted by Ser363 in CD299, making the

interaction impossible in CD299 [S72] and ii) minor sequence variations in the neck

domain for tetramerization, which has 23-amino-acid repeats, account for the

significantly enhanced stability of CD299 aggregates compared to CD209 tetramers

[S73]. In gauging the potential of mouse models to illuminate the physiological

significance of these C-type lectins, the occurrence of a recent, independent divergence

of the murine gene family leading to a total of seven expressed genes and a pseudogene,

six proteins proven to be lectins, is worth noting [S74].

CD328

Three separate approaches all converged to the identification, cloning and

characterization of expression of this CD marker: immunization of mice with human NK

cell clones, resulting in an antibody specific for adhesion inhibitory receptor molecule-1

(AIRM1/p75), screening of a human primary dendritic cell cDNA library for clones with

sequence similarity with the CD33 (siglec-3) gene and homology searches in the dbEST

division of the GenBank database [S75-77]. The structure of CD328 is composed of one

V-set and two C2-set Ig-like modules, which led to its classificiation as siglec-7, and

common inhibitory signaling motifs (Figure 2). It is related to siglec-5 (CD170) and

identical in modular design to siglecs-6, 8, and 9, produced by NK, dendritic and CD8+ T

cell, respectively. Ligand engagement (including 2,8-linked sialosides) negatively

impacts NK cell cytotoxicity, as shown in response to recognition of ganglioside GD3 and

the disialosyl globopentaosylceramide DSGb5 [S78].

CD335/CD337

The natural cytotoxicity receptors NKp46 (CD335) and NKp30 (CD337) are

glycoproteins with two C2-set (CD335) or one V-set (CD337) Ig-like domain(s) (Figure

2). They exert their trigger capacity via association with signaling proteins that have

immunoreceptor tyrosine-based activating motifs (ITAMs), mirroring how CD94 teams

10

up with ITIM-containing proteins to dampen NK cell responses [S79, S80]. Similar to

CD94, heparan sulfate-derived oligosaccharides are binding partners, as are N-glycans

with 2,3-sialylation or sLex (CD15s) determinants [S81].

11

Table 1. CD-classified lectins (and lectin-like proteins) without PDB entry

Name Lectin class Modular design Expression Sugar specificity Function Ref.CD22 (siglec-2)

I-type (siglec) 1 V-set and 6 C2-set Ig-like domainstransmembrane region4 ITIM/ITIM-like sites, 1 growth factor receptor-bound protein 2 (Grb2)-binding motif

B cells Neu5Ac2,6Gal-(1,4GlcNAc(-6-sulfate))

Negative regulator of B cell receptor signaling (inhibitory BCR coreceptor like CD72), also in response to binding complexes of antigen with soluble IgM, Grb2-dependent activation of alternative (positive) signaling

[S82, S83]

CD33(siglec-3)

I-type (siglec) 1 V-set and 1 C2-set Ig-like domainstransmembrane region2 ITIM/ITIM-like sites

Myeloid lineage incl. circulating monocytes, activated T/NK cells

Preference for Neu5Ac2,6Gal(1,4GlcNAc)

mouse: sTn (CD175s)

Inhibitory signaling on cell activation/proliferation

[S84]

CD72(Lyb-2)

C-type (like) disulfide-linked homodimer with C-type lectin-like domain and leucine zippertransmembrane region2 ITIM/ITIM-like sites

B lineage cells(downregulated in plasma cells)

(CD5(?), CD100) Negative regulator of B cell receptor signaling (inhibitory BCR coreceptor, like CD22)

[S85]

CD83 I-type (siglec) 1 V-type Ig-like domaintransmembrane region40 amino-acid-long cytoplasmic tail

Mature dendritic cells

Sialic acid-dependent binding to monocyte glycoprotein (72kDa)

Assumed role in adhesion of dendritic cells to monocytes or subset of activated T cells

[S86]

12

CD168(RHAMM: receptor for hyaluronic acid-mediated motility; IHABP: intracellular hyaluronic acid-binding protein)

Hyaladherin (without link domain)

C-terminal Bx7B motif in isoforms

Cell surface and intracellularly in many cell types (isoforms of 58-95 kDa)

Hyaluronic acid Motility during wound repair and cell growth

[S87]

CD205(DEC-205)

C-type (like) Cysteine-rich domain, fibronectin type II domain, 10 C-type lectin/lectin-like domainstransmembrane region cytoplasmic (31-amino-acid-long) tail

Dendritic cells, thymic cortical epithelium

?

(self) antigen uptake [S88]

CD301(MGL: macrophage galactose-type lectin)

C-type C-type CRD, neck domain for trimerizationtransmembrane regioncytoplasmic (29-amino-acid-long) tail with internalization signal

Dendritic cells, macrophages

(sialyl)Tn (CD175(s))

in mouse: CD301a: Lea,x

CD301b: Tn

Internalization/antigen presentation, pathogen/tumor pattern recognition, T cell recognition

[S89]

13

CD302(DEC-205/DEC-205-associated C-type Lectin-1 (DCL-1) fusion protein)

C-type (like) DEC-205 ectodomain and DCL-1 C-type lectin-like domaintransmembrane regioncytoplasmic (43-amino-acid-long) tail

Monocytes, macrophages, granulocytes, dendritic cells

?

Endocytosis/phagocytosis, adhesion of antigen-presenting cells

[S90]

CD303(BDCA-2: blood DC antigen 2; LEC4C)

C-type (like) C-type lectin-like domain transmembrane regioncytoplasmic (21-amino-acid-long) tail

Peripheral dendritic cells, monocytes, macrophages, neutrophils

?

Antigen capture, antagonizes TLR signaling via Syk recruitment

[S91]

CD314(NKG2D)

C-type Disulfide-linked homodimer with C-type CRDtransmembrane regioncytoplasmic tail associating with DAP-10

NK cells, T cells, CD8+ T cells

2,3-sialylated N-glycans, heparin/heparan sulfate

NK cell activation receptor

[S92, S93, S94, S95, S96]

CD327 I-type (siglec) 1 V-set and 2 C2-set Ig-like domainstransmembrane region2 ITIM/ITIM-like sites

B cells, trophoblasts

Neu5Ac2,6GalNAc (sTn (CD175s))

Negative regulator of trophoblast invasiveness in interplay with glycodelin-A

[S97]

14

CD329(siglec-9)

I-type (siglec) 1 V-set and 2 C2-set Ig-like domains transmembrane region2 ITIM/ITIM-like sites

Monocytes, neutrophils, subset of NK cells, immature dendritic cells

Neu5Ac2,3/6-Gal1,4GlcNAc

Negative regulator of neutrophil growth and T cell receptor signaling, induces anti-inflammatory cytokines in macrophages

[S98]

CD330(siglec-10)

I-type (siglec) 1 V-set and 4 C2-set Ig-like domainstransmembrane region2 ITIM/ITIM-like sites, 1 Grb2-binding motif

Eosinophils, monocytes, subset of NK cells, CD19+

B cells, CD4+ T cells

Neu5Ac2,3/6-Gal1,4GlcNAc

Host protection by negative regulation of response to danger-associated molecular patterns (with CD24) or to activated T cells (with CD52)

[S99]

for information on CD69 (AIM: activation inducer molecule) /CD161 (KLRB1, NKR-P1A): reports on lectin activity have been corrected [S100, S101] or retracted [S102, S103]

15

References

S1 Hoffmeister, K.M. (2011) The role of lectins and glycans in platelet clearance. J. Thromb. Haemost. 9 Suppl 1, 35-43S2 Kijimoto-Ochiai, S. (2002) CD23 (the low-affinity IgE receptor) as a C-type lectin: a multidomain and multifunctional molecule. Cell. Mol. Life Sci. 59, 648-664S3 Acharya, M., et al. (2010) CD23/Fc RII: molecular multi-tasking. ε Clin. Exp. Immunol. 162, 12-23S4 Jackson, D.E. (2003) The unfolding tale of PECAM-1. FEBS Lett. 540, 7-14S5 Marelli-Berg, F.M., et al. (2013) An immunologist's guide to CD31 function in T-cells. J. Cell Sci. 126, 2343-2352S6 Gandhi, N.S., et al. (2008) Platelet endothelial cell adhesion molecule 1 (PECAM-1) and its interactions with glycosaminoglycans: 1. Molecular modeling studies. Biochemistry 47, 4851-4862S7 Buddecke, E. (2009) Proteoglycans. In The Sugar Code. Fundamentals of glycosciences (Gabius, H.-J., ed), pp. 199-216, Wiley-VCHS8 Misra, S., et al. (2011) Hyaluronan-CD44 interactions as potential targets for cancer therapy. FEBS J. 278, 1429-1443S9 Zuber, C. and Roth, J. (2009) N-Glycosylation. In The Sugar Code. Fundamentals of glycosciences (Gabius, H.-J., ed), pp. 87-110, Wiley-VCHS10 Ledeen, R.W. and Wu, G. (2009) Neurobiology meets glycosciences. In The Sugar Code. Fundamentals of glycosciences (Gabius, H.-J., ed), pp. 495-516, Wiley-VCHS11 Kleene, R. and Schachner, M. (2004) Glycans and neural cell interactions. Nat. Rev. Neurosci. 5, 195-208S12 Gowans, J.L. and Knight, E.J. (1964) The route of recirculation of lymphocytes in the rat. Proc. R. Soc. London Series B 159, 257-282S13 Vestweber, D. and Blanks, J.E. (1999) Mechanisms that regulate the function of the selectins and their ligands. Physiol. Rev. 79, 181-213S14 Magnani, J.L. (2004) The discovery, biology, and drug development of sialyl Lea and sialyl Lex. Arch. Biochem. Biophys. 426, 122-131S15 Binder, F.P., et al. (2012) Sialyl Lewisx: a "pre-organized water oligomer"? Angew. Chem. Int. Ed. 51, 7327-7331S16 Somers, W.S., et al. (2000) Insights into the molecular basis of leukocyte tethering and rolling revealed by structures of P- and E-selectin bound to sLex and PSGL-1. Cell 103, 467-479S17 Angiari, S., et al. (2014) TIM-1 glycoprotein binds the adhesion receptor P-selectin and mediates T cell trafficking during inflammation and autoimmunity. Immunity 40, 542-553S18 McEver, R.P. and Zhu, C. (2010) Rolling cell adhesion. Annu. Rev. Cell Dev. Biol. 26, 363-396S19 Houchins, J.P., et al. (1991) DNA sequence analysis of NKG2, a family of related cDNA clones encoding type II integral membrane proteins on human natural killer cells. J. Exp. Med. 173, 1017-1020S20 Yabe, T., et al. (1993) A multigene family on human chromosome 12 encodes natural killer-cell lectins. Immunogenetics 37, 455-460

16

S21 Aramburu, J., et al. (1990) A novel functional cell surface dimer (Kp43) expressed by natural killer cells and T cell receptor- /γ δ+ T lymphocytes. I. Inhibition of the IL-2-dependent proliferation by anti-Kp43 monoclonal antibody. J. Immunol. 144, 3238-3247S22 Lopez-Botet, M., et al. (1998) The CD94/NKG2 C-type lectin receptor complex. Curr. Top. Microbiol. Immunol. 230, 41-52S23 Chabre, Y.M. and Roy, R. (2009) The chemist’s way to prepare multivalency. In The Sugar Code. Fundamentals of glycosciences (Gabius, H.-J., ed), pp. 53-70, Wiley-VCHS24 Ohyama, C., et al. (2002) Natural killer cells attack tumor cells expressing high levels of sialyl Lewis x oligosaccharides. Proc. Natl. Acad. Sci. USA 99, 13789-13794S25 Imaizumi, Y., et al. (2009) NKG2D and CD94 bind to multimeric 2,3-linked N-αacetylneuraminic acid. Biochem. Biophys. Res. Commun. 382, 604-608S26 Higai, K., et al. (2009) NKG2D and CD94 bind to heparin and sulfate-containing polysaccharides. Biochem. Biophys. Res. Commun. 386, 709-714S27 Weiler, H. and Isermann, B.H. (2003) Thrombomodulin. J. Thromb. Haemost. 1, 1515-1524S28 Turnbull, J.E. (2015) Complexity and functional diversity of glycosaminoglycans: master cell regulators. Trends Biochem. Sci., in pressS29 Shi, C.S., et al. (2008) Lectin-like domain of thrombomodulin binds to its specific ligand Lewis Y antigen and neutralizes lipopolysaccharide-induced inflammatory response. Blood 112, 3661-3670S30 Kuo, C.H., et al. (2012) The recombinant lectin-like domain of thrombomodulin inhibits angiogenesis through interaction with Lewis Y antigen. Blood 119, 1302-1313S31 Crocker, P.R. and Gordon, S. (1986) Properties and distribution of a lectin-like hemagglutinin differentially expressed by murine stromal tissue macrophages. J. Exp. Med. 164, 1862-1875S32 Crocker, P.R., et al. (1991) Purification and properties of sialoadhesin, a sialic acid-binding receptor of murine tissue macrophages. EMBO J. 10, 1661-1669S33 Klaas, M. and Crocker, P.R. (2012) Sialoadhesin in recognition of self and non-self. Semin. Immunopathol. 34, 353-364S34 O'Neill, A.S., et al. (2013) Sialoadhesin: a macrophage-restricted marker of immunoregulation and inflammation. Immunology 138, 198-207S35 Tan, F.Y.Y., et al. (2015) Sugar coating: bacterial protein glycosylation and host-microbe interactions. Trends Biochem. Sci., in pressS36 Mucklow, S., et al. (1995) Sialoadhesin (Sn) maps to mouse chromosome 2 and human chromosome 20 and is not linked to the other members of the sialoadhesin family, CD22, MAG, and CD33. Genomics 28, 344-346S37 Cornish, A.L., et al. (1998) Characterization of siglec-5, a novel glycoprotein expressed on myeloid cells related to CD33. Blood 92, 2123-2132S38 Avril, T., et al. (2005) Siglec-5 (CD170) can mediate inhibitory signaling in the absence of immunoreceptor tyrosine-based inhibitory motif phosphorylation. J. Biol. Chem. 280, 19843-19851S39 Patel, N., et al. (1999) OB-BP1/Siglec-6: a leptin- and sialic acid-binding protein of the immunoglobulin superfamily. J. Biol. Chem. 274, 22729-22738S40 Yamanaka, M., et al. (2009) Deletion polymorphism of SIGLEC14 and its functional implications. Glycobiology 19, 841-846S41 Carlin, A.F., et al. (2009) Group B Streptococcus suppression of phagocyte functions by protein-mediated engagement of human Siglec-5. J. Exp. Med. 206, 1691-1699S42 Schlesinger, P.H., et al. (1978) Plasma clearance of glycoproteins with terminal mannose and N-acetylglucosamine by liver non-parenchymal cells. Studies with beta-

17

glucuronidase, N-acetyl- -D-glucosaminidase, ribonuclease B and agalacto-βorosomucoid. Biochem. J. 176, 103-109S43 Corfield, A. and Berry, M. (2015) Current aspects of eukaryotic glycosylation. Trends Biochem. Sci., in pressS44 Brady, R.O. (2006) Enzyme replacement for lysosomal diseases. Annu. Rev. Med. 57, 283-296S45 Taylor, P.R., et al. (2005) The mannose receptor: linking homeostasis and immunity through sugar recognition. Trends Immunol. 26, 104-110S46 Martinez-Pomares, L. (2012) The mannose receptor. J. Leukoc. Biol. 92, 1177-1186S47 Fiete, D., et al. (1997) The macrophage/endothelial cell mannose receptor cDNA encodes a protein that binds oligosaccharides terminating with SO4-4-GalNAcb1,4GlcNAcb or Man at independent sites. Proc. Natl. Acad. Sci. USA 94, 11256-11261S48 Martínez-Pomares, L., et al. (1999) Cell-specific glycoforms of sialoadhesin and CD45 are counterreceptors for the cysteine-rich domain of the mannose receptor. J. Biol. Chem. 274, 35211-35218S49 Marttila-Ichihara, F., et al. (2008) Macrophage mannose receptor on lymphatics controls cell trafficking. Blood 112, 64-72S50 Valladeau, J., et al. (1999) The monoclonal antibody DCGM4 recognizes Langerin, a protein specific of Langerhans cells, and is rapidly internalized from the cell surface. Eur. J. Immunol. 29, 2695-2704S51 Feinberg, H., et al. (2011) Structural basis for langerin recognition of diverse pathogen and mammalian glycans through a single binding site. J. Mol. Biol. 405, 1027-1039S52 Feinberg, H., et al. (2013) Common polymorphisms in human langerin change specificity for glycan ligands. J. Biol. Chem. 288, 36762-36771S53 Ruiz, F.M., et al. (2014) Natural single amino acid polymorphism (F19Y) in human galectin-8: detection of structural alterations and increased growth-regulatory activity on tumor cells. FEBS J. 281, 1446-1464S54 Chabrol, E., et al. (2012) Glycosaminoglycans are interactants of Langerin: comparison with gp120 highlights an unexpected calcium-independent binding mode. PLoS One 7, e50722S55 McGreal, E.P., et al. (2005) Ligand recognition by antigen-presenting cell C-type lectin receptors. Curr. Opin. Immunol. 17, 18-24S56 Lee, R.T., et al. (2011) Survey of immune-related, mannose/fucose-binding C-type lectin receptors reveals widely divergent sugar-binding specificities. Glycobiology 21, 512-520S57 Soilleux, E.J., et al. (2000) DC-SIGN, a related gene, DC-SIGNR, and CD23 form a cluster on 19p13. J. Immunol. 165, 2937-2942S58 Curtis, B.M., et al. (1992) Sequence and expression of a membrane-associated C-type lectin that exhibits CD4-independent binding of human immunodeficiency virus envelope glycoprotein gp120. Proc. Natl. Acad. Sci. USA 89, 8356-8360S59 Geijtenbeek, T.B., et al. (2000) Identification of DC-SIGN, a novel dendritic cell-specific ICAM-3 receptor that supports primary immune responses. Cell 100, 575-585S60 Gabius, H.-J. (2006) Cell surface glycans: the why and how of their functionality as biochemical signals in lectin-mediated information transfer. Crit. Rev. Immunol. 26, 43-79S61 Zhang, F., et al. (2014) DC-SIGN, DC-SIGNR and LSECtin: C-type lectins for infection. Int. Rev. Immunol. 33, 54-66

18

S62 Vautier, S., et al. (2012) C-type lectin receptors and cytokines in fungal immunity. Cytokine 58, 89-99S63 Van Breedam, W., et al. (2014) Bitter-sweet symphony: glycan-lectin interactions in virus biology. FEMS Microbiol. Rev. 38, 598-632S64 Dahms, N.M. and Hancock, M.K. (2002) P-type lectins. Biochim. Biophys. Acta 1572, 317-340S65 Castonguay, A.C., et al. (2011) Mannose 6-phosphate receptor homology (MRH) domain-containing lectins in the secretory pathway. Biochim. Biophys. Acta 1810, 815-826S66 Caixeiro, N.J., et al. (2013) Silencing the mannose 6-phosphate/IGF-II receptor differentially affects tumorigenic properties of normal breast epithelial cells. Int. J. Canc. 133, 2542-2550S67 Wu, K., et al. (1996) Characterization of a novel member of the macrophage mannose receptor type C lectin family. J. Biol. Chem. 271, 21323-21330S68 Isacke, C.M., et al. (1990) p180, a novel recycling transmembrane glycoprotein with restricted cell type expression. Mol. Cell. Biol. 10, 2606-2618S69 Behrendt, N., et al. (2000) A urokinase receptor-associated protein with specific collagen binding properties. J. Biol. Chem. 275, 1993-2002S70 Jurgensen, H.J., et al. (2011) A novel functional role of collagen glycosylation: interaction with the endocytic collagen receptor uparap/ENDO180. J. Biol. Chem. 286, 32736-32748S71 Engelholm, L.H., et al. (2003) uPARAP/Endo180 is essential for cellular uptake of collagen and promotes fibroblast collagen adhesion. J. Cell Biol. 160, 1009-1015S72 Guo, Y., et al. (2004) Structural basis for distinct ligand-binding and targeting properties of the receptors DC-SIGN and DC-SIGNR. Nat. Struct. Mol. Biol. 11, 591-598S73 Yu, Q.D., et al. (2009) Autonomous tetramerization domains in the glycan-binding receptors DC-SIGN and DC-SIGNR. J. Mol. Biol. 387, 1075-1080S74 Powlesland, A.S., et al. (2006) Widely divergent biochemical properties of the complete set of mouse DC-SIGN-related proteins. J. Biol. Chem. 281, 20440-20449S75 Falco, M., et al. (1999) Identification and molecular cloning of p75/AIRM1, a novel member of the sialoadhesin family that functions as an inhibitory receptor in human natural killer cells. J. Exp. Med. 190, 793-802S76 Nicoll, G., et al. (1999) Identification and characterization of a novel siglec, siglec-7, expressed by human natural killer cells and monocytes. J. Biol. Chem. 274, 34089-34095S77 Angata, T. and Varki, A. (2000) Siglec-7: a sialic acid-binding lectin of the immunoglobulin superfamily. Glycobiology 10, 431-438S78 Kawasaki, Y., et al. (2010) Ganglioside DSGb5, preferred ligand for Siglec-7, inhibits NK cell cytotoxicity against renal cell carcinoma cells. Glycobiology 20, 1373-1379S79 Moretta, L., et al. (2006) Surface NK receptors and their ligands on tumor cells. Semin. Immunol. 18, 151-158S80 Kruse, P.H., et al. (2014) Natural cytotoxicity receptors and their ligands. Immunol. Cell Biol. 92, 221-229S81 Ito, K., et al. (2011) Binding of natural cytotoxicity receptor NKp46 to sulfate- and

2,3-NeuAc-containing glycans and its mutagenesis. α Biochem. Biophys. Res. Commun. 406, 377-382S82 Schwartz-Albiez, R., et al. (1991) CD22 antigen: biosynthesis, glycosylation and surface expression of a B lymphocyte protein involved in B cell activation and adhesion. Int. Immunol. 3, 623-633S83 Nitschke, L. (2009) CD22 and Siglec-G: B-cell inhibitory receptors with distinct functions. Immunol. Rev. 230, 128-143

19

S84 Cao, H. and Crocker, P.R. (2011) Evolution of CD33-related siglecs: regulating host immune functions and escaping pathogen exploitation? Immunology 132, 18-26S85 Nitschke, L. and Tsubata, T. (2004) Molecular interactions regulate BCR signal inhibition by CD22 and CD72. Trends Immunol. 25, 543-550S86 Scholler, N., et al. (2001) CD83 is an I-type lectin adhesion receptor that binds monocytes and a subset of activated CD8+ T cells [corrected]. J. Immunol. 166, 3865-3872S87 Jiang, D., et al. (2011) Hyaluronan as an immune regulator in human diseases. Physiol. Rev. 91, 221-264S88 Shrimpton, R.E., et al. (2009) CD205 (DEC-205): a recognition receptor for apoptotic and necrotic self. Mol. Immunol. 46, 1229-1239S89 Mortezai, N., et al. (2013) Tumor-associated Neu5Ac-Tn and Neu5Gc-Tn antigens bind to C-type lectin CLEC10A (CD301, MGL). Glycobiology 23, 844-852S90 Kato, M., et al. (2007) The novel endocytic and phagocytic C-Type lectin receptor DCL-1/CD302 on macrophages is colocalized with F-actin, suggesting a role in cell adhesion and migration. J. Immunol. 179, 6052-6063S91 Geijtenbeek, T.B. and Gringhuis, S.I. (2009) Signalling through C-type lectin receptors: shaping immune responses. Nat. Rev. Immunol. 9, 465-479S92 Macher, B.A., et al. (1988) A novel carbohydrate, differentiation antigen on fucogangliosides of human myeloid cells recognized by monoclonal antibody VIM-2. J. Biol. Chem. 263, 10186-10191S93 Siebert, H.-C., et al. (2006) α2,3/α2,6-Sialylation of N-glycans: non-synonymous signals with marked developmental regulation in bovine reproductive tracts. Biochimie 88, 399-410S94 Spitalnik, P.F. and Spitalnik, S.L. (1995) The P blood group system: biochemical, serological, and clinical aspects. Transfus. Med. Rev. 9, 110-122S95 Suchanowska, A., et al. (2012) A single point mutation in the gene encoding Gb3/CD77 synthase causes a rare inherited polyagglutination syndrome. J. Biol. Chem. 287, 38220-38230S96 Nudelman, E., et al. (1983) A glycolipid antigen associated with Burkitt lymphoma defined by a monoclonal antibody. Science 220, 509-511S97 Lam, K.K., et al. (2011) Glycodelin-A protein interacts with Siglec-6 protein to suppress trophoblast invasiveness by down-regulating extracellular signal-regulated kinase (ERK)/c-Jun signaling pathway. J. Biol. Chem. 286, 37118-37127S98 Cheong, K.A., et al. (2011) A novel function of Siglec-9 A391C polymorphism on T cell receptor signaling. Int. Arch. Allergy Immunol. 154, 111-118S99 Bandala-Sanchez, E., et al. (2013) T cell regulation mediated by interaction of soluble CD52 with the inhibitory receptor siglec-10. Nat. Immunol. 14, 741-748S100 Childs, R.A., et al. (1999) Recombinant soluble human CD69 dimer produced in Escherichia coli: reevaluation of saccharide binding. Biochem. Biophys. Res. Commun. 266, 19-23S101 Rozbesky, D., et al. (2014) Re-evaluation of binding properties of recombinant lymphocyte receptors NKR-P1A and CD69 to chemically synthesized glycans and peptides. Int. J. Mol. Sci. 15, 1271-1283S102 (2013) Retraction: Oligosaccharide ligands for NKR-P1 protein activate NK cells and cytotoxicity. Nature 500, 490S103 (2014) Retraction. Synthesis of LacdiNAc-terminated glycoconjugates by mutant galactosyltransferase – A way to new glycodrugs and materials. Glycobiology 24, 399

20