Biofactories in a tube
Imagine switching on a protein factory at home by adding yeast to a tube. No lab required.
How yeast-based biofactories work
Identify a protein
Choose gene(s) for the proteins you want to produce.
Insert plasmids
Clone those genes into plasmids alongside a custom, maltose-triggered promoter, then insert them into the yeast.
Culture the yeast
Grow the engineered yeast.
Switch on production
Maltose activates the promoter and the yeast fill with protein (or display proteins on their surface).
Consume it
Yeast survives stomach acid, then delivers the manufactored proteins to the gut. M cells in the gut may take up particular proteins, potentially helping maintain the body's natural defenses.
Proven in animals
Across more than 20 published studies, yeast expressing antigen proteins fed orally have induced antibody responses in mice, chickens, pigs, and fish.
| Pathogen | Tested in | Yeast species | Preparation | Antigen | Antigen location | Immune response / effects measured | Study |
|---|---|---|---|---|---|---|---|
| SARS-CoV-2 | Mice | P. pastoris | killed | FliC–RBD–foldon | surface | serum IgG · fecal IgA | Saveii 2026 |
| BK polyomavirus | Mice | S. cerevisiae | live | VP1 | internal | serum nAb | Soleymani 2025(preprint) |
| SARS-CoV-2 | Mice | S. cerevisiae | live | RBD–CpE | secreted | IgG · fecal IgA · IFN-γ | Ramos 2025(preprint) |
| SARS-CoV-2 | Mice | P. pastoris | killed | S+N epitopes | surface | IgG2a · IgG2b · fecal IgA | de Macêdo 2025 |
| F4⁺ E. coli (ETEC) | Mice | S. cerevisiae | live | FaeG | surface | IgG · fecal sIgA · IL-2/IL-4/IFN-γ · survival | Hu 2025 |
| Infectious bursal disease | Mice | S. cerevisiae | live | VP2 | surface | IgG · fecal sIgA · IFN-α/γ | Li 2023 |
| SARS-CoV-2 | Mice | S. cerevisiae | live | RBD–FP | surface | serum IgG · IgA | Zhang 2022 |
| SARS-CoV-2 | Mice | S. cerevisiae | killed | RBD | surface | IgG · sIgA · IFN-γ · IL-4 · nAb | Gao 2021 |
| Influenza H7N9 | Mice | S. cerevisiae | killed | HA | surface | IgG · HI · IFN-γ / IL-4 | Lei 2020 |
| Dengue | Mice | S. cerevisiae | live | Co1–scEDIII | surface | IgG | Bal 2018a |
| Dengue | Mice | S. cerevisiae | live + killed | LTB–scEDIII | internal | IgG · sIgA · nAb · proliferation | Bal 2018b |
| Enterovirus 71 | Mice | S. cerevisiae | live | VP1 | surface | IgG · IgM · IgA · nAb · IFN-γ / TNF-α | Zhang 2016 |
| PRRSV | Mice | K. lactis | killed | GP5 | internal | sIgA · IFN-γ⁺ T cells | Zhao 2014 |
| Fowl adenovirus | Chickens | S. cerevisiae | live | Fiber-2 | surface | antibody · protection | Cao 2022 |
| Influenza H5N1 | Chickens | S. cerevisiae | killed | HA | surface | IgG · IgA · HI · IFN-γ / IL-4 | Lei 2021 |
| Infectious bursal disease | Chickens | P. pastoris | killed | VP2 | internal | protection only | Taghavian 2013 |
| African swine fever | Pigs | S. cerevisiae | live | p30/p54–Fc | surface | serum IgG · serum IgA | Chen 2021 |
| Porcine epidemic diarrhea | Mice & piglets | P. pastoris | live | S1 | internal | serum IgG · mucosal IgA | Wang 2016 |
| Porcine circovirus 2 | Pigs | S. cerevisiae | killed | Cap | surface | fecal sIgA · IFN-α/γ · ↓viraemia | Patterson 2015 |
First human data
Potential benefits
Easy, cheap to make
Oral or nasal delivery (no needles/injections)
Can be dried and be made shelf stable
Refrigeration not required during shipment
Can potentially boost the immune system's mucosal defenses
Generally recognized as safe
Participate in Radvac’s research
Radvac is planning a study on genetically-modified yeast that manufactures shell proteins from BK & JC Polyomavirus. Submit your email to express interest in being a participant in this upcoming study and to be informed about future studies.