THE FIRST COVID-19 SPECIFIC HUMAN IMMUNE ANTIBODY LIBRARY FOR PHAGE DISPLAY

Engaged in fighting the COVID-19 pandemic? Need fast antibody generation for diagnostic or therapeutic applications? Try our LiAb-SFCOVID-19™ library and antibody phage display services for therapeutic applications to get high-affinity human antibodies in less than 2 months.

How will our antibody library fight the
COVID-19 pandemic?

The COVID-19 pandemic caused a global health emergency necessitating a strong cooperation between all the health and life science community to combine their core expertise for the development of diagnostic and therapeutic solutions. ProteoGenix contributes to this global effort with the development of a new COVID-19 immune human library: LiAb-SFCOVID-19™. Our mission is to share our expertise in antibody generation with the scientific community to allow them accelerating the development of fast and reliable immunoassays as well as efficient therapies.

Development Of Immunoassays

It is well known that diagnostics plays a major role in the containment of COVID-19. Among the statistics taken into account for the implementation of control measures, the number of patients infected remains one of the most important. The viral test is mostly measured by nucleic acid testing and detects the genetic presence of SARS-CoV-2 indicating if a patient is infected or not. It is mainly done using RT-PCR but is known to be too slow to be performed in high amounts. An alternative approach overcoming this limitation is the antigen testing. This test is already commonly used for influenza. It is a rapid lateral flow test based on the principle of a sandwich design. Briefly, a membrane is coated with a primary antibody (capture antibody) recognizing virus particles in a sample (here mucus from the tested patient). By adding a chemically modified secondary antibody, the presence of the virus can be simply detected. However, these tests are also known for their low sensitivity. Increasing their sensitivity remains a crucial challenge to be able to test millions of people accurately. Several solutions exist to increase the sensitivity of these tests. One of them consists in using high affinity capture antibodies. This is now made possible is less than 2 months thanks to our immune COVID-19 antibody library for phage display.

Development Of Therapeutic Antibodies

Several strategies have been employed to try to mitigate the COVID-19 pandemic. This includes:

• The treatment of severe symptoms such as the “cytokine storm” by repurposing existing therapeutic antibodies
• The re-evaluation of SARS-CoV antibodies that might cross-react with SARS-CoV-2
• The decreasing of the viral load by administration of COVID-19 survivor plasma.

Even if this latest strategy demonstrated promising results, it suffers from various limitations such as low reproducibility (due to batch-to-batch variations) or the risk of transmitting blood-borne infections. One alternative strategy to overcome these limitations would be the development of neutralizing monoclonal antibody therapies which can be easily produced in large quantities and in a reproducible manner.

COVID-19 targets for the development of neutralizing antibodies

The development of highly efficient antibody therapies depends on the capacity of determining the right target. Previous studies demonstrated that two proteins of the coronavirus particles were particularly interesting for the development of neutralizing antibodies, namely the spike protein (S protein) and the nucleocapsid protein (N protein). Up to now, most of the therapeutic antibodies developed focused on the spike protein (S protein), a homotrimeric protein anchored in the viral membrane. Each monomer is composed of two subunits S1 and S2. S1 contains the N-terminal domain and the receptor binding domain (RBD)responsible for the attachment with human Angiotensin converting receptor 2 (ACE2) whereas S2 exposes a viral fusion peptide. Most of the therapeutic antibodies currently tested in clinical trials are neutralizing antibodies (nAbs) targeting epitopes from the RBD domain of the Spike protein. It was also discovered that the targeting of the N-terminal domain of the Spike protein of SARS-CoV-2, located on the S1 subunit, could also lead to the development of promising neutralizing antibodies.

Looking for ready-to-use antigens to generate your anti-SARS-CoV-2 antibodies? Get them in 1 week thanks to our COVID-19 proteins and peptides catalog.

What are the solutions to avoid escape mutants?

The rapid emergence of escape mutants was one of the main problems observed for SARS-CoV and MERS. The lessons learned from these previous coronaviruses forced scientists to anticipate this hypothesis. Two solutions are mainly used to avoid escape mutants:

1. Target highly conserved epitopes
2. Produce neutralizing antibody cocktails targeting simultaneously non-RBD and RBD epitopes.

Are you developing such a treatment? Choose our COVID-19 phage display library and benefit from several advantages:

• Develop antibodies against several antigens in less than 2 months
• Get high-affinity human antibodies

Need more information? Contact your account manager!

You could also be interested in:

• Nanobody production