+
Open data
-
Basic information
| Entry | ![]() | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Title | CryoEM structure of anti-MHC-I Fab M1/42 complex with H2-Dd | |||||||||
Map data | main map file | |||||||||
Sample |
| |||||||||
Keywords | MHC-I / anti-mouse-mAb / H2-Dd / M1/42 / anti-MHC-I antibody / anti-tumor / cancer immunotherapy / ANTITUMOR PROTEIN / ANTITUMOR PROTEIN-Immune System complex | |||||||||
| Function / homology | Function and homology informationEndosomal/Vacuolar pathway / DAP12 interactions / Antigen Presentation: Folding, assembly and peptide loading of class I MHC / ER-Phagosome pathway / DAP12 signaling / Immunoregulatory interactions between a Lymphoid and a non-Lymphoid cell / regulation of membrane depolarization / Dectin-2 family / cellular defense response / antigen processing and presentation of peptide antigen via MHC class I ...Endosomal/Vacuolar pathway / DAP12 interactions / Antigen Presentation: Folding, assembly and peptide loading of class I MHC / ER-Phagosome pathway / DAP12 signaling / Immunoregulatory interactions between a Lymphoid and a non-Lymphoid cell / regulation of membrane depolarization / Dectin-2 family / cellular defense response / antigen processing and presentation of peptide antigen via MHC class I / positive regulation of plasma membrane raft polarization / positive regulation of receptor clustering / Neutrophil degranulation / host cell endosome membrane / lumenal side of endoplasmic reticulum membrane / regulation of iron ion transport / cellular response to iron(III) ion / negative regulation of iron ion transport / negative regulation of forebrain neuron differentiation / antigen processing and presentation of exogenous protein antigen via MHC class Ib, TAP-dependent / iron ion transport / peptide antigen assembly with MHC class I protein complex / regulation of erythrocyte differentiation / response to molecule of bacterial origin / MHC class I peptide loading complex / HFE-transferrin receptor complex / transferrin transport / cellular response to iron ion / negative regulation of receptor-mediated endocytosis / positive regulation of T cell cytokine production / antigen processing and presentation of endogenous peptide antigen via MHC class I / MHC class I protein complex / peptide antigen assembly with MHC class II protein complex / negative regulation of neurogenesis / cellular response to nicotine / positive regulation of receptor-mediated endocytosis / MHC class II protein complex / positive regulation of T cell mediated cytotoxicity / multicellular organismal-level iron ion homeostasis / peptide antigen binding / antigen processing and presentation of exogenous peptide antigen via MHC class II / phagocytic vesicle membrane / positive regulation of immune response / positive regulation of T cell activation / negative regulation of epithelial cell proliferation / sensory perception of smell / positive regulation of cellular senescence / MHC class II protein complex binding / T cell differentiation in thymus / antimicrobial humoral immune response mediated by antimicrobial peptide / late endosome membrane / negative regulation of neuron projection development / antibacterial humoral response / protein refolding / cellular response to lipopolysaccharide / clathrin-dependent endocytosis of virus by host cell / amyloid fibril formation / protein homotetramerization / defense response to Gram-negative bacterium / intracellular iron ion homeostasis / learning or memory / defense response to Gram-positive bacterium / immune response / viral protein processing / fusion of virus membrane with host plasma membrane / external side of plasma membrane / innate immune response / lysosomal membrane / fusion of virus membrane with host endosome membrane / viral envelope / virion attachment to host cell / host cell plasma membrane / virion membrane / structural molecule activity / Golgi apparatus / protein homodimerization activity / : / membrane / identical protein binding / plasma membrane / cytosol Similarity search - Function | |||||||||
| Biological species | ![]() ![]() | |||||||||
| Method | single particle reconstruction / cryo EM / Resolution: 2.67 Å | |||||||||
Authors | Jiang J / Natarajan K / Margulies DH / Lei H / Huang R | |||||||||
| Funding support | United States, 1 items
| |||||||||
Citation | Journal: Commun Biol / Year: 2026Title: Structural mechanism of anti-MHC-I antibody blocking of inhibitory NK cell receptors in tumor immunity. Authors: Jiansheng Jiang / Abir K Panda / Kannan Natarajan / Haotian Lei / Shikha Sharma / Lisa F Boyd / Reanne R Towler / Sruthi Chempati / Javeed Ahmad / Abraham J Morton / Zabrina C Lang / Yi Sun ...Authors: Jiansheng Jiang / Abir K Panda / Kannan Natarajan / Haotian Lei / Shikha Sharma / Lisa F Boyd / Reanne R Towler / Sruthi Chempati / Javeed Ahmad / Abraham J Morton / Zabrina C Lang / Yi Sun / Nikolaos Sgourakis / Martin Meier-Schellersheim / Rick K Huang / Ethan M Shevach / David H Margulies / ![]() Abstract: Anti-major histocompatibility complex class I (MHC-I) mAbs can stimulate immune responses to tumors and infections by blocking suppressive signals delivered via various immune inhibitory receptors. ...Anti-major histocompatibility complex class I (MHC-I) mAbs can stimulate immune responses to tumors and infections by blocking suppressive signals delivered via various immune inhibitory receptors. To understand such functions, we determined the structure of a highly cross-reactive anti-human MHC-I mAb, B1.23.2, in complex with the MHC-I molecule HLA-B*44:05 by both cryo-electron microscopy (cryo-EM) and X-ray crystallography. Structural models determined by the two methods were essentially identical revealing that B1.23.2 binds a conserved region on the α2 helix that overlaps the killer immunoglobulin-like receptor (KIR) binding site. Structural comparison to KIR/HLA complexes reveals a mechanism by which B1.23.2 blocks inhibitory receptor interactions, leading to natural killer (NK) cell activation. B1.23.2 treatment of the human KLM-1 pancreatic cancer model in humanized (NSG-IL15) mice provides evidence of suppression of tumor growth. Such anti-MHC-I mAb that block inhibitory KIR/HLA interactions may prove useful for tumor immunotherapy. | |||||||||
| History |
|
-
Structure visualization
| Supplemental images |
|---|
-
Downloads & links
-EMDB archive
| Map data | emd_46600.map.gz | 32.3 MB | EMDB map data format | |
|---|---|---|---|---|
| Header (meta data) | emd-46600-v30.xml emd-46600.xml | 29 KB 29 KB | Display Display | EMDB header |
| FSC (resolution estimation) | emd_46600_fsc.xml | 8.4 KB | Display | FSC data file |
| Images | emd_46600.png | 82 KB | ||
| Masks | emd_46600_msk_1.map | 64 MB | Mask map | |
| Filedesc metadata | emd-46600.cif.gz | 7.8 KB | ||
| Others | emd_46600_half_map_1.map.gz emd_46600_half_map_2.map.gz | 59.5 MB 59.5 MB | ||
| Archive directory | http://ftp.pdbj.org/pub/emdb/structures/EMD-46600 ftp://ftp.pdbj.org/pub/emdb/structures/EMD-46600 | HTTPS FTP |
-Related structure data
| Related structure data | ![]() 9d72MC ![]() 8tq6C ![]() 9d73C ![]() 9d74C ![]() 9oa9C M: atomic model generated by this map C: citing same article ( |
|---|---|
| Similar structure data | Similarity search - Function & homology F&H Search |
-
Links
| EMDB pages | EMDB (EBI/PDBe) / EMDataResource |
|---|---|
| Related items in Molecule of the Month |
-
Map
| File | Download / File: emd_46600.map.gz / Format: CCP4 / Size: 64 MB / Type: IMAGE STORED AS FLOATING POINT NUMBER (4 BYTES) | ||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Annotation | main map file | ||||||||||||||||||||||||||||||||||||
| Projections & slices | Image control
Images are generated by Spider. | ||||||||||||||||||||||||||||||||||||
| Voxel size | X=Y=Z: 0.83 Å | ||||||||||||||||||||||||||||||||||||
| Density |
| ||||||||||||||||||||||||||||||||||||
| Symmetry | Space group: 1 | ||||||||||||||||||||||||||||||||||||
| Details | EMDB XML:
|
-Supplemental data
-Mask #1
| File | emd_46600_msk_1.map | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Projections & Slices |
| ||||||||||||
| Density Histograms |
-Half map: half map A
| File | emd_46600_half_map_1.map | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Annotation | half map A | ||||||||||||
| Projections & Slices |
| ||||||||||||
| Density Histograms |
-Half map: half map B
| File | emd_46600_half_map_2.map | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Annotation | half map B | ||||||||||||
| Projections & Slices |
| ||||||||||||
| Density Histograms |
-
Sample components
-Entire : Complex of Anti mouse Fab M1/42 and MHC-I H2-Dd
| Entire | Name: Complex of Anti mouse Fab M1/42 and MHC-I H2-Dd |
|---|---|
| Components |
|
-Supramolecule #1: Complex of Anti mouse Fab M1/42 and MHC-I H2-Dd
| Supramolecule | Name: Complex of Anti mouse Fab M1/42 and MHC-I H2-Dd / type: complex / ID: 1 / Parent: 0 / Macromolecule list: all Details: The sample was mixed 1:1 mole ratio of Fab and H2-Dd and purified. with concentration of 1.0 mg/ml |
|---|---|
| Source (natural) | Organism: ![]() |
| Molecular weight | Theoretical: 90.129 KDa |
-Macromolecule #1: Beta-2-microglobulin
| Macromolecule | Name: Beta-2-microglobulin / type: protein_or_peptide / ID: 1 / Number of copies: 1 / Enantiomer: LEVO |
|---|---|
| Source (natural) | Organism: ![]() |
| Molecular weight | Theoretical: 11.529153 KDa |
| Recombinant expression | Organism: ![]() |
| Sequence | String: IQKTPQIQVY SRHPPENGKP NILNCYVTQF HPPHIEIQML KNGKKIPKVE MSDMSFSKDW SFYILAHTEF TPTETDTYAC RVKHASMAE PKTVYWDRD UniProtKB: Beta-2-microglobulin |
-Macromolecule #2: Fab M1/42 Light Chain
| Macromolecule | Name: Fab M1/42 Light Chain / type: protein_or_peptide / ID: 2 / Number of copies: 1 / Enantiomer: LEVO |
|---|---|
| Source (natural) | Organism: ![]() |
| Molecular weight | Theoretical: 23.555971 KDa |
| Recombinant expression | Organism: Homo sapiens (human) |
| Sequence | String: DIQMTQSPSS MSASLGDKVT INCLASEDIG NYLSWYQQRP GKSPKLMIYG VTNLEDGVPS RFSGSRSGSD YSLTINSLGY DDEGIYHCH EYYEYPFTFG SGTKLEIKRA DAAPTVSIFP PSTEQLATGG ASVVCLMNNF YPRDISVKWK IDGTERRDGV L DSVTDQDS ...String: DIQMTQSPSS MSASLGDKVT INCLASEDIG NYLSWYQQRP GKSPKLMIYG VTNLEDGVPS RFSGSRSGSD YSLTINSLGY DDEGIYHCH EYYEYPFTFG SGTKLEIKRA DAAPTVSIFP PSTEQLATGG ASVVCLMNNF YPRDISVKWK IDGTERRDGV L DSVTDQDS KDSTYSMSST LSLTKADYES HNLYTCEVVH KTSSSPVVKS FNRNE |
-Macromolecule #3: Surface protein gp120
| Macromolecule | Name: Surface protein gp120 / type: protein_or_peptide / ID: 3 / Number of copies: 1 / Enantiomer: LEVO |
|---|---|
| Source (natural) | Organism: synthetic construct (others) |
| Molecular weight | Theoretical: 1.075265 KDa |
| Sequence | String: RGPGRAFVTI UniProtKB: Envelope glycoprotein gp160 |
-Macromolecule #4: H-2 class I histocompatibility antigen, D-D alpha chain
| Macromolecule | Name: H-2 class I histocompatibility antigen, D-D alpha chain type: protein_or_peptide / ID: 4 / Number of copies: 1 / Enantiomer: LEVO |
|---|---|
| Source (natural) | Organism: ![]() |
| Molecular weight | Theoretical: 31.819361 KDa |
| Recombinant expression | Organism: ![]() |
| Sequence | String: SHSLRYFVTA VSRPGFGEPR YMEVGYVDNT EFVRFDSDAE NPRYEPRARW IEQEGPEYWE RETRRAKGNE QSFRVDLRTA LRYYNQSAG GSHTLQWMAG CDVESDGRLL RGYWQFAYDG CDYIALNEDL KTWTAADMAA QITRRKWEQA GAAERDRAYL E GECVEWLR ...String: SHSLRYFVTA VSRPGFGEPR YMEVGYVDNT EFVRFDSDAE NPRYEPRARW IEQEGPEYWE RETRRAKGNE QSFRVDLRTA LRYYNQSAG GSHTLQWMAG CDVESDGRLL RGYWQFAYDG CDYIALNEDL KTWTAADMAA QITRRKWEQA GAAERDRAYL E GECVEWLR RYLKNGNATL LRTDPPKAHV THHRRPEGDV TLRCWALGFY PADITLTWQL NGEELTQEME LVETRPAGDG TF QKWASVV VPLGKEQKYT CHVEHEGLPE PLTLRW UniProtKB: H-2 class I histocompatibility antigen, D-D alpha chain |
-Macromolecule #5: Fab M1/42 Heavy Chain
| Macromolecule | Name: Fab M1/42 Heavy Chain / type: protein_or_peptide / ID: 5 / Number of copies: 1 / Enantiomer: LEVO |
|---|---|
| Source (natural) | Organism: ![]() |
| Molecular weight | Theoretical: 23.754752 KDa |
| Recombinant expression | Organism: Homo sapiens (human) |
| Sequence | String: QVTLKESGPG MLQPSKTLSL TCSFSGFSLS TSGLVVNWIR QPSGKSLEWL AAIDWDGDEY YNPSPKSRLT VSKDTSNTQV FLKITSVDT VDTATYYCAR SRRYGRYSGA FDYWGLGVMV TVSSAETTAP SVYPLAPGTA LKSNSMVTLG CLVKGYFPEP V TVTWNSGA ...String: QVTLKESGPG MLQPSKTLSL TCSFSGFSLS TSGLVVNWIR QPSGKSLEWL AAIDWDGDEY YNPSPKSRLT VSKDTSNTQV FLKITSVDT VDTATYYCAR SRRYGRYSGA FDYWGLGVMV TVSSAETTAP SVYPLAPGTA LKSNSMVTLG CLVKGYFPEP V TVTWNSGA LSSGVHTFPA VLQSGLYTLT SSVTVPSSTW SSQAVTCNVA HPASSTKVDK KIVP |
-Experimental details
-Structure determination
| Method | cryo EM |
|---|---|
Processing | single particle reconstruction |
| Aggregation state | particle |
-
Sample preparation
| Concentration | 1.0 mg/mL |
|---|---|
| Buffer | pH: 8 / Component - Concentration: 0.25 mg/ml / Component - Name: TBS |
| Grid | Model: EMS Lacey Carbon / Material: GOLD / Mesh: 300 / Support film - Material: CARBON / Support film - topology: HOLEY / Support film - Film thickness: 1200 / Pretreatment - Type: GLOW DISCHARGE / Pretreatment - Time: 60 sec. / Pretreatment - Atmosphere: AIR |
| Vitrification | Cryogen name: ETHANE / Chamber humidity: 95 % / Chamber temperature: 277 K / Instrument: FEI VITROBOT MARK IV |
-
Electron microscopy
| Microscope | FEI TITAN KRIOS |
|---|---|
| Temperature | Min: 78.0 K / Max: 80.0 K |
| Image recording | Film or detector model: GATAN K3 BIOQUANTUM (6k x 4k) / Detector mode: SUPER-RESOLUTION / Number grids imaged: 1 / Number real images: 2993 / Average exposure time: 2.5 sec. / Average electron dose: 54.2 e/Å2 |
| Electron beam | Acceleration voltage: 300 kV / Electron source: FIELD EMISSION GUN |
| Electron optics | C2 aperture diameter: 100.0 µm / Calibrated magnification: 60096 / Illumination mode: FLOOD BEAM / Imaging mode: BRIGHT FIELD / Cs: 2.7 mm / Nominal defocus max: 2.0 µm / Nominal defocus min: 0.7000000000000001 µm / Nominal magnification: 105000 |
| Sample stage | Specimen holder model: FEI TITAN KRIOS AUTOGRID HOLDER / Cooling holder cryogen: NITROGEN |
| Experimental equipment | ![]() Model: Titan Krios / Image courtesy: FEI Company |
Movie
Controller
About Yorodumi




Keywords
Authors
United States, 1 items
Citation




















Z (Sec.)
Y (Row.)
X (Col.)













































Homo sapiens (human)
Processing
FIELD EMISSION GUN


