Pseudovirus Service

COVID-19 Pseudovirus Service Description

Pseudovirus

Expresses the SARS-CoV-2 spike protein.

Sample types

Serum / Plasma / Peptides / Proteins / Purified antibodies / Small molecules.

Sample amount to send

Undiluted serum or plasma (100 µL) / Peptides (≥ 200 µg) / Proteins (≥ 25 µg) / Purified antibodies (≥ 20 µg) / Small molecules (≥ 1 mg).

Sample minimum

No sample minimum. We charge our service based on how many 96-well plates are required. Therefore, regardless of whether 1 well is used or all 96 wells, the charge for the service will be the same.

Replicates

We will perform 2 technical replicates unless otherwise requested.

Cell lines

You can choose between the ACE2-expressing cells, human A549 or monkey Vero. If you don't have a preference, we recommend the human A549 cell line.

Controls

Our service includes the following controls:

• "Mock Infection" positive control (pseudovirus with a non-Spike glycoprotein with an ACE2-expressing cell line) at the same dilutions as your sample.
• "No Sample" positive control (cell culture media with ACE2-expressing cell line).
• Negative control (no pseudovirus with an ACE2-expressing cell line).

Duplicate technical replicates will be performed for all controls unless otherwise requested.

Additional negative controls with cells that do not express the ACE2 receptor, mouse NIH3T3 or ovine OFTU cells, can be added to this service upon request (additional fees apply). If you don't have a preference, we recommend the mouse NIH3T3 cell line.

Deliverables

You will receive two files:

• An Excel-based report outlining the samples and their measured luminescence values. These values have already had background signal subtracted from them. The background signal is obtained from duplicate technical replicates of similar cells that have not had pseudovirus incubated with them. The Excel file will also include the inhibition rate(s) of the sample(s) at different dilutions compared to the "No Sample" positive control.
• A Word document summarizing the service background, controls, procedure, and references.

How It Works

In the presence of Spike-ACE2 inhibitors, the level of luminescence will decrease.

Neutralization analysis by SARS-CoV-2-S-driven entry

Pseudoviruses expressing a non-Spike glycoprotein ("glycoprotein") or the SARS-CoV-2 Spike protein on the surface were incubated with A549 cells expressing the ACE2 receptor ("ACE2 cell") or NIH3T3 cells not expressing the ACE2 receptor ("Non-ACE2 cell"). Serum containing a neutralizing antibody was added at 400-, 200-, or 100-fold dilutions. Luminescence reflecting viral entry was measured, and the average luminescence across three independent experiments relative to the "no serum" sample data is shown. Error bars indicate standard deviations.

Western blot analysis for VSV-G and SARS-CVO2-spike

Goat anti mouse IgG-HRP: 1:5000.
Lane: 1: Pseudovirus/VSV-G; 2: Pseudovirus/SARS-COV-2-Spike