6X4T | pdb_00006x4t

Crystal structure of ICOS-L in complex with Prezalumab and VNAR domain

External Resource: Annotation

Domain Annotation: SCOP/SCOPe Classification
Domain Annotation: ECOD Classification
Domain Annotation: CATH
IMGT Antibody Annotation
SAbDab Antibody Annotation
Thera-SAbDab Antibody Annotation
Protein Family Annotation
Gene Ontology: Gene Product Annotation
InterPro: Protein Family Classification
Pharos: Disease Associations

Domain Annotation: SCOP/SCOPe Classification SCOP-e Database Homepage

Chains	Domain Info	Class	Fold	Superfamily	Family	Domain	Species	Provenance Source (Version)
H [auth N]	d6x4tn_	All beta proteins	Immunoglobulin-like beta-sandwich	Immunoglobulin	V set domains (antibody variable domain-like)	automated matches	(Orectolobus maculatus ) [TaxId: 168098 ],	SCOPe (2.08)
G	d6x4tg_	All beta proteins	Immunoglobulin-like beta-sandwich	Immunoglobulin	V set domains (antibody variable domain-like)	automated matches	(Orectolobus maculatus ) [TaxId: 168098 ],	SCOPe (2.08)
F	d6x4tf2	All beta proteins	Immunoglobulin-like beta-sandwich	Immunoglobulin	C1 set domains (antibody constant domain-like)	automated matches	(Homo sapiens ) [TaxId: 9606 ],	SCOPe (2.08)
F	d6x4tf1	All beta proteins	Immunoglobulin-like beta-sandwich	Immunoglobulin	automated matches	automated matches	(Homo sapiens ) [TaxId: 9606 ],	SCOPe (2.08)
E	d6x4te2	All beta proteins	Immunoglobulin-like beta-sandwich	Immunoglobulin	C1 set domains (antibody constant domain-like)	automated matches	(Homo sapiens ) [TaxId: 9606 ],	SCOPe (2.08)
E	d6x4te1	All beta proteins	Immunoglobulin-like beta-sandwich	Immunoglobulin	automated matches	automated matches	(Homo sapiens ) [TaxId: 9606 ],	SCOPe (2.08)
D	d6x4td_	All beta proteins	Immunoglobulin-like beta-sandwich	Immunoglobulin	V set domains (antibody variable domain-like)	automated matches	(Homo sapiens ) [TaxId: 9606 ],	SCOPe (2.08)
B	d6x4tb_	All beta proteins	Immunoglobulin-like beta-sandwich	Immunoglobulin	V set domains (antibody variable domain-like)	automated matches	(Homo sapiens ) [TaxId: 9606 ],	SCOPe (2.08)

Domain Annotation: ECOD Classification ECOD Database Homepage

Chains	Family Name	Domain Identifier	Architecture	Possible Homology	Homology	Topology	Family	Provenance Source (Version)
H [auth N]	Beta-APP	e6x4tN1	A: beta sandwiches	X: Immunoglobulin-like beta-sandwich	H: Immunoglobulin-related	T: Immunoglobulin/Fibronectin type III/E set domains/PapD-like	F: Beta-APP	ECOD (1.6)
G	Beta-APP	e6x4tG1	A: beta sandwiches	X: Immunoglobulin-like beta-sandwich	H: Immunoglobulin-related	T: Immunoglobulin/Fibronectin type III/E set domains/PapD-like	F: Beta-APP	ECOD (1.6)
F	C1-set_4	e6x4tF2	A: beta sandwiches	X: Immunoglobulin-like beta-sandwich	H: Immunoglobulin-related	T: Immunoglobulin/Fibronectin type III/E set domains/PapD-like	F: C1-set_4	ECOD (1.6)
F	V-set	e6x4tF1	A: beta sandwiches	X: Immunoglobulin-like beta-sandwich	H: Immunoglobulin-related	T: Immunoglobulin/Fibronectin type III/E set domains/PapD-like	F: V-set	ECOD (1.6)
E	C1-set_4	e6x4tE2	A: beta sandwiches	X: Immunoglobulin-like beta-sandwich	H: Immunoglobulin-related	T: Immunoglobulin/Fibronectin type III/E set domains/PapD-like	F: C1-set_4	ECOD (1.6)
E	V-set	e6x4tE1	A: beta sandwiches	X: Immunoglobulin-like beta-sandwich	H: Immunoglobulin-related	T: Immunoglobulin/Fibronectin type III/E set domains/PapD-like	F: V-set	ECOD (1.6)
D	C1-set_1	e6x4tD1	A: beta sandwiches	X: Immunoglobulin-like beta-sandwich	H: Immunoglobulin-related	T: Immunoglobulin/Fibronectin type III/E set domains/PapD-like	F: C1-set_1	ECOD (1.6)
D	V-set_12	e6x4tD2	A: beta sandwiches	X: Immunoglobulin-like beta-sandwich	H: Immunoglobulin-related	T: Immunoglobulin/Fibronectin type III/E set domains/PapD-like	F: V-set_12	ECOD (1.6)
B	C1-set_1	e6x4tB1	A: beta sandwiches	X: Immunoglobulin-like beta-sandwich	H: Immunoglobulin-related	T: Immunoglobulin/Fibronectin type III/E set domains/PapD-like	F: C1-set_1	ECOD (1.6)
B	V-set_12	e6x4tB2	A: beta sandwiches	X: Immunoglobulin-like beta-sandwich	H: Immunoglobulin-related	T: Immunoglobulin/Fibronectin type III/E set domains/PapD-like	F: V-set_12	ECOD (1.6)
C	V-set_9	e6x4tC1	A: beta sandwiches	X: Immunoglobulin-like beta-sandwich	H: Immunoglobulin-related	T: Immunoglobulin/Fibronectin type III/E set domains/PapD-like	F: V-set_9	ECOD (1.6)
C	I-set_8	e6x4tC2	A: beta sandwiches	X: Immunoglobulin-like beta-sandwich	H: Immunoglobulin-related	T: Immunoglobulin/Fibronectin type III/E set domains/PapD-like	F: I-set_8	ECOD (1.6)
A	V-set_9	e6x4tA2	A: beta sandwiches	X: Immunoglobulin-like beta-sandwich	H: Immunoglobulin-related	T: Immunoglobulin/Fibronectin type III/E set domains/PapD-like	F: V-set_9	ECOD (1.6)
A	I-set_8	e6x4tA1	A: beta sandwiches	X: Immunoglobulin-like beta-sandwich	H: Immunoglobulin-related	T: Immunoglobulin/Fibronectin type III/E set domains/PapD-like	F: I-set_8	ECOD (1.6)

Domain Annotation: CATH CATH Database Homepage

Chain	Domain	Class	Architecture	Topology	Homology	Provenance Source (Version)
F	2.60.40.10	Mainly Beta	Sandwich	Immunoglobulin-like	Immunoglobulins	CATH (utative)
E	2.60.40.10	Mainly Beta	Sandwich	Immunoglobulin-like	Immunoglobulins	CATH (utative)
D	2.60.40.10	Mainly Beta	Sandwich	Immunoglobulin-like	Immunoglobulins	CATH (utative)
B	2.60.40.10	Mainly Beta	Sandwich	Immunoglobulin-like	Immunoglobulins	CATH (utative)
C	2.60.40.10	Mainly Beta	Sandwich	Immunoglobulin-like	Immunoglobulins	CATH (utative)
A	2.60.40.10	Mainly Beta	Sandwich	Immunoglobulin-like	Immunoglobulins	CATH (utative)

IMGT Antibody Annotation IMGT Database Homepage

Chain	Protein Name	Description	Organism Name	Gene Allele Name(s)	Domain Name(s)	Receptor Type	Receptor Description	Provenance Source
G, H [auth N]	IgNAR (VNAR)	VH	Ginglymostoma cirratum (nurse shark)	IGHV2S401, IGHV2S4501, IGHJ18*01	V-DOMAIN VH	IG	VH	IMGT (202540-0)
E, F	Fab Prezalumab, anti-ICOS-L	L-KAPPA	Homo sapiens (human)	IGKV1D-1601, IGKJ101, IGKC*01	V-DOMAIN V-KAPPA, C-DOMAIN C-KAPPA	IG	FAB-GAMMA-1_KAPPA	IMGT (202540-0)
B, D	Fab Prezalumab, anti-ICOS-L	VH-CH1	Homo sapiens (human)	IGHV3-701, IGHV3-702, IGHV3-703, IGHV3-704, IGHV3-705, IGHJ101, IGHG101, IGHG102, IGHG104, IGHG105, IGHG107, IGHG109, IGHG110, IGHG111, IGHG112, IGHG113, IGHG1*14	V-DOMAIN VH, C-DOMAIN CH1	IG	FAB-GAMMA-1_KAPPA	IMGT (202540-0)
A, C	ICOS 3-232 (Pr19-248)(O75144)	1V-1C-LIKE	Homo sapiens (human)	ICOSLG*01	V-LIKE-DOMAIN V-LIKE, C-LIKE-DOMAIN C-LIKE	-	Protein	IMGT (202540-0)

SAbDab Antibody Annotation SAbDab Database Homepage

Chain	Chain Class	Chain Subclass	Chain Type	Antigen Name(s)	Provenance Source
E, F	Light Chain	IGKV1	Kappa	icos ligand	SAbDab (2025-10-17)
B, D	Heavy Chain	IGHV3	-	icos ligand	SAbDab (2025-10-17)

Thera-SAbDab Antibody Annotation Thera-SAbDab Database Homepage

Chain	Name	Target	Provenance Source
E, F	Prezalumab	ICOSLG, ICOS/CD278	Therapeutic SAbDab (2025-10-17)
B, D	Prezalumab	ICOSLG, ICOS/CD278	Therapeutic SAbDab (2025-10-17)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
A, C	PF07686	Immunoglobulin V-set domain (V-set)	Immunoglobulin V-set domain	This domain is found in antibodies as well as neural protein P0 and CTL4 amongst others.	Domain
A, C	PF22705	Butyrophilin subfamily 3 member A2-like, Ig-C domain (C2-set_3)	Butyrophilin subfamily 3 member A2-like, Ig-C domain	This domain is found in human Butyrophilin subfamily 3 member A2 (BTN3A2), a protein that plays a role in T-cell responses in the adaptive immune response. BTN3A2 shows two extracellular domains: an N-terminal Ig-V like domain (Pfam:PF07686) and a C- ...	This domain is found in human Butyrophilin subfamily 3 member A2 (BTN3A2), a protein that plays a role in T-cell responses in the adaptive immune response. BTN3A2 shows two extracellular domains: an N-terminal Ig-V like domain (Pfam:PF07686) and a C-terminal Ig-C type domain that is located in the centre of the protein sequence [6].	Domain

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
G, H [auth N]	VNAR	-	-	-
E, F	Prezalumab Fab Light chain	-	-	-
B, D	Prezalumab Fab Heavy chain	-	-	-
A, C	ICOS ligand	protein binding binding signaling receptor binding molecular function activator activity molecular function regulator activity signaling receptor regulator activity receptor ligand activity signaling receptor activator activity identical protein binding	cellular response to stimulus immune response-regulating cell surface receptor signaling pathway regulation of cellular process response to stimulus signaling positive regulation of biological process cell communication positive regulation of response to stimulus immune response-activating signaling pathway immune response-regulating signaling pathway positive regulation of immune response regulation of immune system process signal transduction positive regulation of immune system process cellular response to stimulus immune response-regulating cell surface receptor signaling pathway regulation of cellular process response to stimulus signaling positive regulation of biological process cell communication positive regulation of response to stimulus immune response-activating signaling pathway immune response-regulating signaling pathway positive regulation of immune response regulation of immune system process signal transduction positive regulation of immune system process regulation of biological process cell surface receptor signaling pathway immune response-activating cell surface receptor signaling pathway immune response biological regulation T cell receptor signaling pathway regulation of response to stimulus immune system process regulation of immune response cellular process antigen receptor-mediated signaling pathway activation of immune response adaptive immune response multicellular organismal process B cell activation cell activation lymphocyte activation leukocyte activation regulation of biosynthetic process regulation of macromolecule metabolic process gene expression macromolecule biosynthetic process regulation of gene expression biosynthetic process regulation of cytokine production cytokine production regulation of macromolecule biosynthetic process metabolic process regulation of multicellular organismal process macromolecule metabolic process regulation of metabolic process defense response response to stress response to osmotic stress hyperosmotic response response to abiotic stimulus T cell activation positive regulation of cell population proliferation regulation of leukocyte activation regulation of cell activation positive regulation of cell activation lymphocyte proliferation positive regulation of leukocyte activation regulation of leukocyte proliferation cell population proliferation positive regulation of T cell activation positive regulation of lymphocyte proliferation positive regulation of T cell proliferation positive regulation of activated T cell proliferation regulation of cell population proliferation mononuclear cell proliferation regulation of leukocyte cell-cell adhesion positive regulation of leukocyte proliferation positive regulation of multicellular organismal process regulation of activated T cell proliferation positive regulation of leukocyte cell-cell adhesion leukocyte proliferation leukocyte cell-cell adhesion activated T cell proliferation positive regulation of cell-cell adhesion positive regulation of lymphocyte activation cell adhesion cell-cell adhesion positive regulation of mononuclear cell proliferation regulation of cell-cell adhesion positive regulation of cellular process T cell proliferation regulation of lymphocyte proliferation positive regulation of cell adhesion regulation of cell adhesion regulation of T cell activation regulation of T cell proliferation regulation of mononuclear cell proliferation regulation of lymphocyte activation cellular developmental process cell development mononuclear cell differentiation lymphocyte differentiation cell activation involved in immune response CD4-positive, alpha-beta T cell differentiation CD4-positive, alpha-beta T cell differentiation involved in immune response alpha-beta T cell differentiation involved in immune response alpha-beta T cell differentiation T cell activation involved in immune response alpha-beta T cell activation involved in immune response cell differentiation CD4-positive, alpha-beta T cell activation leukocyte activation involved in immune response anatomical structure development alpha-beta T cell activation T follicular helper cell differentiation T cell differentiation lymphocyte activation involved in immune response developmental process T-helper cell differentiation hemopoiesis T cell differentiation involved in immune response immune effector process leukocyte differentiation	cell periphery cellular anatomical structure cell surface membrane plasma membrane external side of plasma membrane side of membrane extracellular exosome membrane-bounded organelle extracellular vesicle extracellular organelle extracellular region organelle extracellular space cell periphery cellular anatomical structure cell surface membrane plasma membrane external side of plasma membrane side of membrane extracellular exosome membrane-bounded organelle extracellular vesicle extracellular organelle extracellular region organelle extracellular space vesicle extracellular membrane-bounded organelle intracellular organelle intracellular anatomical structure intracellular membrane-bounded organelle

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
A, C	IPR036179	Immunoglobulin-like domain superfamily	Homologous Superfamily
A, C	IPR013106	Immunoglobulin V-set domain	Domain
A, C	IPR003599	Immunoglobulin domain subtype	Domain
A, C	IPR053896	Butyrophilin subfamily 3 member A2-like, Ig-C domain	Domain
A, C	IPR013783	Immunoglobulin-like fold	Homologous Superfamily
A, C	IPR050504	Immunoglobulin superfamily BTN/MOG domain-containing protein	Family
A, C	IPR007110	Immunoglobulin-like domain	Domain

Pharos: Disease Associations Pharos Homepage Annotation

Chains	Drug Target	Associated Disease
A, C	Pharos: O75144	ulcerative colitis celiac disease

RCSB PDB Core Operations are funded by the U.S. National Science Foundation (DBI-2321666), the US Department of Energy (DE-SC0019749), and the National Cancer Institute, National Institute of Allergy and Infectious Diseases, and National Institute of General Medical Sciences of the National Institutes of Health under grant R01GM157729.