Related Experiment Video

Updated: Aug 11, 2026

A Uniform Shear Assay for Human Platelet and Cell Surface Receptors via Cone-plate Viscometry
04:32

A Uniform Shear Assay for Human Platelet and Cell Surface Receptors via Cone-plate Viscometry

Published on: June 5, 2019

A humanized antibody specific for the platelet integrin gpIIb/IIIa

M S Co1, S Yano, R K Hsu

  • 1Protein Design Labs, Inc., Mountain View, CA 94043.

Journal of Immunology (Baltimore, Md. : 1950)
|March 15, 1994
PubMed

C4G1, a murine mAb reactive with the platelet gpIIb/IIIa integrin, was humanized for potential treatment of thrombosis-related disorders. The variable regions of light- and heavy-chain cDNAs from the C4G1 hybridoma were first cloned and sequenced. Humanized C4G1 Ab of the IgG1 isotype was constructed by combining the complementarity-determining regions of C4G1 with human framework and constant regions. The human framework was chosen to maximize homology with the C4G1 variable region sequence, and a computer model of C4G1 was used to aid design of the final framework sequence. Genetic constructs were also developed to produce Fab and F(ab')2 fragments of the humanized C4G1 Ab. The humanized IgG1 Ab as well as the Fab and F(ab')2 fragments showed equivalent binding affinities to their murine counterparts, indicating no loss in binding affinity during the humanization process. The humanized Ab and its fragments were also shown to inhibit platelet aggregation and to inhibit binding of fibrinogen to gpIIb/IIIa in vitro.

More Related Videos

A Flow Cytometry-Based High-Throughput Technique for Screening Integrin-Inhibitory Drugs04:15

A Flow Cytometry-Based High-Throughput Technique for Screening Integrin-Inhibitory Drugs

Published on: February 2, 2024

An In Vitro Assay to Study Platelet Migration Using RGD-Functionalized Avidin-Biotin Tethers05:43

An In Vitro Assay to Study Platelet Migration Using RGD-Functionalized Avidin-Biotin Tethers

Published on: November 8, 2024

Related Concept Videos

Integrins01:10

Integrins

Animal and protozoan cells do not have cell walls to help maintain shape and provide structural stability. Instead, these eukaryotic cells secrete a sticky mass of carbohydrates and proteins into the spaces between adjacent cells. This network of proteins and molecules is called an extracellular matrix or ECM.
Some ECM proteins assemble into a basement membrane to which the remaining components adhere. Proteoglycans typically form the bulk of the ECM while fibrous proteins, like collagen,...
Activation of Integrins01:15

Activation of Integrins

Integrins bind ligands and transmit information from outside the cell to inside or vice-versa through an "outside-in signaling" or "inside-out signaling."
In "outside-in signaling," external factors in the extracellular space bind to exposed ligand binding sites on integrins. This causes the inactive protein to undergo a conformational change to become active. Integrins are often clustered on the cell membrane. Repetitive and regularly spaced ligand binding events provide an effective stimulus.
Intracellular Signaling Affects Focal Adhesions01:17

Intracellular Signaling Affects Focal Adhesions

Integrins act both as extracellular input receivers and as intracellular processing activators. As their name suggests, integrins are entirely integrated into the membrane structure. Their hydrophobic membrane-spanning regions interact with the phospholipid bilayer's hydrophobic region. These membrane receptors provide extracellular attachment sites for effectors like hormones and growth factors. They activate intracellular response cascades when their effectors are bound and active.
Some...