Whole-Cell Antigen Presentation Antibody Service

In the initiation of an immune response in mammals, an antigen is not processed directly by helper T cells; it is first taken up, processed, and presented by antigen-presenting cells. This suggests a practical route for membrane proteins: if a cell can be engineered to express the target antigen, that antigen appears densely on the cell surface together with the determinants the immune system recognizes, and the whole cell can then be used to immunize an animal — in effect, using the cell as a stand-in for a professional antigen-presenting cell.

The advantage of this route is fidelity. The transmembrane protein is expressed in situ in a eukaryotic system, so it keeps its full post-translational modification, and because the cell membrane serves as the display surface, the native structural features of the target are preserved. The trade-off is specificity. A cell is large relative to the target antigen and carries surface modifications that are not part of the target, so while immunogenicity is practically assured, the effectiveness and specificity of the response must be secured on purpose — by expressing the target at high level and, especially, by extensive downstream screening to identify and discard antibodies that recognize irrelevant antigens.

What the Service Covers

• Display-cell preparation – constructing cells that present the target membrane protein on their surface.
• Antigen presentation design – arranging the target so it is displayed as an immune system sees a native membrane protein.
• Immunization – using the display cells as the immunogen to raise the response.
• Extensive screening – identifying and excluding candidates that bind non-target surface features.
• Validation – confirming the selected antibody recognizes the target in the intended application.

Advantages and Trade-offs

When Whole-Cell Presentation Fits

• Conformation is the priority – when the antibody must recognize the protein as it appears in a membrane.
• The protein resists purification – when producing enough clean, correctly folded antigen is impractical.
• Modification matters – when post-translational modification is part of the epitope.
• Screening capacity is available – when the project can support the downstream screening the route requires.

Workflow

• Design the display cell – express the target membrane protein on a suitable cell surface.
• Confirm presentation – verify that the target is displayed at the required level.
• Immunize – raise the response using the display cells.
• Screen – test candidates and remove those directed at non-target features.
• Validate and deliver – confirm the antibody against the target and supply it with data.

Applications

• Conformation-sensitive targets – antibodies that must bind the folded membrane protein.
• Hard-to-purify proteins – targets for which a purified antigen is not readily available.
• Receptor and channel research – reagents for membrane proteins studied in their native setting.
• Functional studies – antibodies used to probe the activity of a membrane protein in cells.

Why Work With Us

Whole-cell immunization succeeds or fails on two things: how well the target is displayed and how rigorously the resulting antibodies are screened. We treat both as central — designing the display cell so the target is presented at high level in a native-like form, and screening hard enough to remove antibodies that bind the cell rather than the protein of interest. The result is an antibody selected against how the target actually appears on a membrane.