We use cookies to understand how you use our site and to improve your experience. This includes personalizing content and advertising. To learn more, click here. By continuing to use our site, you accept our use of cookies. Cookie Policy.

Features Partner Sites Information LinkXpress
Sign In
Advertise with Us
PURITAN MEDICAL

Download Mobile App




Electron Microscopy Technique Boosts Development of Antibody-Based Vaccines

By LabMedica International staff writers
Posted on 22 Aug 2018
Print article
Image: With the new method, the researchers were able to image polyclonal antibody/HIV envelope complexes at a resolution of 4.7 angstroms. At this resolution, the researchers discovered that in rabbits, antibodies specific to a vulnerable site on HIV\'s outer glycan layer (blue shapes) are structurally highly convergent and closely resemble a previously isolated monoclonal antibody (green and teal ribbons) (Photo courtesy of Dr. Lars Hangartner, Scripps Research Institute).
Image: With the new method, the researchers were able to image polyclonal antibody/HIV envelope complexes at a resolution of 4.7 angstroms. At this resolution, the researchers discovered that in rabbits, antibodies specific to a vulnerable site on HIV\'s outer glycan layer (blue shapes) are structurally highly convergent and closely resemble a previously isolated monoclonal antibody (green and teal ribbons) (Photo courtesy of Dr. Lars Hangartner, Scripps Research Institute).
The novel use of an electron microscope imagining technique enabled vaccine developers to follow the design process of structure-based vaccines in real time.

Characterizing polyclonal antibody responses via currently available methods is inherently complex and difficult. Mapping epitopes in an immune response is typically incomplete, which creates a barrier to fully understanding the humoral response to antigens and hinders rational vaccine design efforts.

To improve the antibody design process, investigators at the Scripps Research Institute (La Jolla, CA, USA) developed a method for characterizing polyclonal responses by using electron microscopy to produce negatively stained images of viruses bound to potential neutralizing antibodies. They applied this method to the immunization of rabbits with an HIV-1 envelope glycoprotein vaccine candidate, BG505 SOSIP.664.

The investigators reported in the August 7, 2018, online edition of the journal Immunity that they detected known epitopes within the polyclonal sera and revealed how antibody responses evolved during the prime-boosting strategy to ultimately result in a neutralizing antibody response. They uncovered previously unidentified epitopes, including an epitope proximal to one recognized by human broadly neutralizing antibodies as well as potentially distracting non-neutralizing epitopes.

High-resolution, three-dimensional images of the antibodies with their viral targets were obtained using cryo-electron microscopy (cryo-EM). Cryo-EM is an analytical technique that provides near-atomic structural resolution without requirements for crystallization or limits on molecular size and complexity imposed by the other techniques. Cryo-EM allows the observation of specimens that have not been stained or fixed in any way, showing them in their native environment while integrating multiple images to form a three-dimensional model of the sample.

"We can now watch antibody responses evolve almost in real time," said senior author Dr. Lars Hangartner, associate professor at the Scripps Research Institute. "This method has the potential to change the pace at which we can develop vaccines."

Related Links:
Scripps Research Institute

Platinum Member
COVID-19 Rapid Test
OSOM COVID-19 Antigen Rapid Test
HLX
POCT Fluorescent Immunoassay Analyzer
FIA Go
Gold Member
Real-time PCR System
GentierX3 Series

Print article

Channels

Clinical Chemistry

view channel
Image: Reaching speeds up to 6,000 RPM, this centrifuge forms the basis for a new type of inexpensive, POC biomedical test (Photo courtesy of Duke University)

POC Biomedical Test Spins Water Droplet Using Sound Waves for Cancer Detection

Exosomes, tiny cellular bioparticles carrying a specific set of proteins, lipids, and genetic materials, play a crucial role in cell communication and hold promise for non-invasive diagnostics.... Read more

Molecular Diagnostics

view channel
Image: MOF materials efficiently enrich cfDNA and cfRNA in blood through simple operational process (Photo courtesy of Science China Press)

Blood Circulating Nucleic Acid Enrichment Technique Enables Non-Invasive Liver Cancer Diagnosis

The ability to diagnose diseases early can significantly enhance the effectiveness of clinical treatments and improve survival rates. One promising approach for non-invasive early diagnosis is the use... Read more

Hematology

view channel
Image: The low-cost portable device rapidly identifies chemotherapy patients at risk of sepsis (Photo courtesy of 52North Health)

POC Finger-Prick Blood Test Determines Risk of Neutropenic Sepsis in Patients Undergoing Chemotherapy

Neutropenia, a decrease in neutrophils (a type of white blood cell crucial for fighting infections), is a frequent side effect of certain cancer treatments. This condition elevates the risk of infections,... Read more

Pathology

view channel
Image: The OvaCis Rapid Test discriminates benign from malignant epithelial ovarian cysts (Photo courtesy of INEX)

Intra-Operative POC Device Distinguishes Between Benign and Malignant Ovarian Cysts within 15 Minutes

Ovarian cysts represent a significant health issue for women globally, with up to 10% experiencing this condition at some point in their lives. These cysts form when fluid collects within a thin membrane... Read more
Copyright © 2000-2024 Globetech Media. All rights reserved.