Overview
Cat allergy is far from being a “minor issue.” Studies estimate that around 400 million to 1.6 billion people worldwide are affected, meaning roughly 1 in 5 people may be allergic to cats [1]. Our own survey further confirmed this: among 703 valid responses, nearly two-thirds of participants reported either definite or possible cat allergies. Yet, even when facing symptoms, many people still choose to live with cats. Survey data suggest that a substantial share of affected owners continue cohabiting with cats—for example, a European patient-education survey reported that ≈40% wished to keep their cats despite symptoms [2]; a U.S. public poll suggested that ≈80–85% would not relinquish their cats even if advised by physicians [3]. (Both are non-academic surveys, cited here to reflect attitudes rather than clinical evidence.) This conflict between emotional reliance and health risks highlights the urgency of finding an innovative and ethical solution.
To explore potential technological pathways, we chose to investigate RNA interference (RNAi) as a way to reduce the expression of cat allergen proteins. Unlike drugs or antibody-based cat food, RNAi has the potential to reduce allergens directly at the source in a safe and reversible manner [4][5]. In accordance with iGEM high school safety regulations, animal experiments were strictly prohibited. Moreover, the two commonly used feline cell lines (CRFK and F81) do not naturally express these allergen genes, making direct validation impossible.
To address this, we built an engineered yeast GFP reporter system. Since budding yeast (S. cerevisiae) naturally lacks a Dicer/Argonaute-based RNAi pathway, we utilized a partner-provided reconstituted strain carrying a functional RNAi system [4][6]. Allergen mRNA fragments were fused to GFP so that effective shRNAs would reduce fluorescence, allowing rapid and low-risk screening. This system not only supported our own experiments but also provides a safe, reusable validation method for future iGEM high school teams that may not have access to mammalian cell models.
At the same time, we asked ourselves: if this technology truly works, how could it move beyond the lab? To explore this question, we engaged with clinicians, pet food companies, NGOs, policy researchers, and investors. They reminded us that beyond efficacy, we must also consider safety, cost, and user experience [7]. These insights inspired us to design surveys, create FAQs, and even brainstorm potential product formats—such as snacks or feed additives—to envision its real-world application.
We hope this project will not remain confined to a competition, but rather become a long-term solution that helps humans and cats coexist more harmoniously.
Our project name, FeliSilence, combines Felis (Latin for “cat”) and Silence, symbolizing our goal to silence allergens, not cats. It reflects our belief that biotechnology should be both effective and empathetic, allowing science to create gentler forms of companionship between humans and animals.
Why this project?
Background and Motivation: An underestimated yet persistent real pain point
During our brainstorming sessions in March–April, we set our sights on a “real and long-standing issue around us.” Some of our teammates have suffered from cat allergies for years, yet are unwilling to leave their cats. This shifted our focus from cat hair to the actual allergenic proteins: the real culprits are not the fur itself, but proteins (such as Fel d 1/2/4/7) secreted by cats and deposited on hair/dander[8,9].
Epidemiological and molecular diagnostic studies suggest that cat sensitization/allergy is common worldwide, affecting approximately 10–20% of adults(Equivalent to ~0.8–1.6 billion people globally given current population; ranges reflect study definitions and regions.)[10,11]. Fel d 1 is the primary allergen, secreted mainly by sebaceous and salivary glands[8,9]. Through grooming and contact, it spreads into the air and triggers rhinitis, asthma, and reactions[12].
Additionally, the contradiction between emotional attachment and health risk is widespread. Even with a confirmed allergy, many cat owners choose to continue living with their pets[13].
We therefore concluded that this is not a niche problem, but a long-standing conflict that spans different ages, regions, and scenarios: companion vs. allergies.
Our first-hand evidence: survey and field visits
An online anonymous survey (703 responses, July 2025) revealed:
● Allergy status: clear allergy 30.9%｜possible 17.2%｜uncertain 16.9% (total 64.9% with clear or potential risk)
● Interest in “technologies reducing cat allergens”: very interested 48.0% (only 7.0% not interested)
● Acceptance of “RNA interference (a non-gene-editing approach)”: acceptable 34.0%｜hesitant 55.0% (concerns centered on safety and cat welfare)
● Willingness to use if cat health is ensured: willing 54.9%｜depends 35.6%
Field visits (cat-owning households & NGOs): several interviewees reported that about one-third of family members experience allergic symptoms; the risk of abandonment is notably higher when children are allergic. Participants generally hoped for a “safe, cat-friendly, and perceivable” solution and suggested risk communication should be included in pre-adoption education.
What we learned from the survey (Implications):
1. 64.9% of respondents showed a clear or potential risk of allergies — the demand is significant (internal data, HP/Survey).
2. Safety and animal welfare are the top priorities for adopting the new technology.
3. Given assurance of cat health, the willingness to try is strong.
Current problem in the market: why “existing methods” cannot truly solve the problem
By analyzing stakeholder opinions across the “symptom end — environment end — cat end,” we found common issues of poor long-term compliance, financial burden, or only superficial relief:
● Symptom end (human): Drugs, desensitization, and IgE monoclonals can alleviate symptoms, but side effects, compliance, and cost are concerns. They also cannot reduce the continuous production of allergens inside cats (feedback from clinicians).
● Environment end (home): Air purifiers, cleaning, sprays can reduce concentration in the environment, but cannot stop secretion at the source, and are limited by usage frequency and setting (feedback from doctors and families).
● Cat end (current market): Anti-Fel d 1 IgY-based diets/wipes lower active Fel d 1 while in use; however, mechanistically they do not block new secretion, so levels rise after discontinuation, limiting long-term user perception and compliance. Users often complain about insufficient short-term effect, with repurchase hinging on whether there is a “noticeable difference” (industry interviews).
● Extreme solution (gene-edited cats): Theoretically “one-time,” but faces ethical/regulatory barriers, high costs, and short-term impracticality (academic/policy feedback).
→ The reality: many methods exist, but none can stably and affordably reduce allergens “at the source” in everyday households, while safeguarding cat welfare at the same time.
What stakeholders are saying: multidimensional confirmation of necessity
● Clinicians: Human-side approaches “alleviate but do not cure,” with side effects and compliance issues. They recommend evaluating allergen reduction from the cat side, alongside early regulatory approval and long-term safety validation (Dept. of Allergy, 2nd Affiliated Hospital of Zhejiang University).
● NGOs & adoption groups: Abandonment risk is real, especially in households with allergic children; they call for pre-adoption education and cat-friendly solutions (Lucky Cat NGO / local NGOs).
● Pet food companies: Short-term perceivability drives repurchase; treats/additives are more acceptable. A 30–40% price premium is viable if “noticeable change” is guaranteed (Zhejiang Kesheng / Petty).
● Regulatory experts: Oversight depends on composition and claims. If managed as veterinary medicine, systematic safety data and long-term follow-up are required; recommend multi-scenario compliance planning (Weijiexin Biotech).
● Investors/industry: Avoid general “pet market” assumptions; focus on high-need segments. Short- to mid-term delivery is the main bottleneck. Suggest phased validation, with strong emphasis on user experience and cost (several investors).
Community & Inter-team Engagement
In addition to clinicians, NGOs, companies, and investors, we also treated the iGEM community itself as a stakeholder. Through inter-team exchanges, we not only shared progress but also tested the replicability, acceptance, and communication strategies of our project within a peer scientific community.
1) CCIC National Conference
During our project presentation, we connected with dozens of teams. Notably:
● BNDS-China (also focusing on cat-related topics) showed us that cat allergy is not just a niche curiosity but a broadly recognized societal pain point within the iGEM network itself.
● SZU-China (focusing on RNAi for two consecutive years) reinforced that RNAi’s bottleneck is not only the design of sequences but primarily the delivery and validation path.
→ Impact: We therefore integrated “delivery is the greatest bottleneck” into our HP design constraints, a point that echoed what clinicians and investors had already emphasized.
2) Technical Deep Dive with SZU-China
We held a detailed online meeting with SZU-China, discussing RNAi experimental standards.
● We heard: in vitro transcription provides purer RNA, reducing background noise; RNA modifications critically influence silencing efficacy.
● We changed: we incorporated RNA purity and source considerations into our yeast GFP validation system, ensuring reproducibility and credibility.
→ This strengthened our conviction that even a high school team should hold itself to community-level reproducibility standards.
3) BNDS-China Campus Exchange
We met BNDS-China, UCAS, RDFZ-China, Keystone and others at the BNDS Eleventh Campus.
● We heard: many teams placed safety disclaimers and FAQ-style risk communication before introducing benefits in community talks.
● We changed: we built a lightweight campus talk kit (slides + FAQ + 5-question survey) for our own school, and updated our outreach scripts to foreground safety (“non-medical advice,” “cat-friendly & reversible”) before discussing potential benefits.
Summary:
Inter-team engagement was not “just activity” but an essential HP dimension:
● It validated that our problem (cat allergy) resonates across different teams and contexts.
● It reminded us that RNAi credibility depends on reproducibility, not just design.
● It taught us to reframe education by leading with risk communication, not benefits.
This community feedback, together with clinicians, NGOs, companies, and investors, gave us a four-dimensional evidence chain for necessity, safety, and feasibility: medical – industrial – policy – community.
What non-technical constraints does this imply for a solution? (Design Requirements)
From the above evidence chain, we distilled a “necessity–constraint set” for real-world family scenarios (without predefining specific technologies):
1.Source effect: Must reduce allergen production at the cat end (not just symptom/environment “band-aids”).
2.Safety & animal welfare: Must be homeostasis-friendly, explainable, sustainable, with transparent validation and communication.
3.Perceivability & compliance: Effects should be noticeable, with low user burden, and predictable on-use/off-use patterns.
4.Accessibility & affordability: Must fall within acceptable monthly costs (per user/enterprise feedback) and support long-term use.
5.Regulatory readiness & verifiability: Plan materials and milestones “validate first, file later,” anticipating multi-scenario compliance paths.
6.Education & communication: Accompanied by pre-adoption education and myth-busting (e.g., “not the cat hair itself”), raising societal awareness.
Conclusion:
We are not doing this project to develop a “cool technology,” but because in the real world, countless families are trapped in the long-standing conflict between companionship and symptoms. Existing approaches struggle to stably address the source within daily family life. The voices and evidence from multiple stakeholders converge on the same point: we need a path toward “safe, cat-friendly, perceivable, affordable, and compliant” source reduction.
Why We Chose RNAi (Instead of Gene Editing / Antibodies / Environmental Control)
RNA interference (RNAi) reduces protein expression at the mRNA level and has the following features:
● Reversibility: Expression of the target protein can be restored once treatment stops, keeping risks controllable. Compared with permanent gene editing, this makes RNAi more suitable for “usable first, optimizable later” real-world family scenarios[14].
● Multi-target coverage: RNAi can simultaneously target key proteins such as Fel d 1, Fel d 4, and Fel d 7, improving applicability across the allergic population. (Fel d 1 accounts for the primary allergen in ~60–90% of cat-allergic patients[15], while Fel d 4/7 serve as important supplements).
● Existing clinical precedent: In 2018, the FDA approved the RNAi drug Patisiran, validating the feasibility and safety of RNAi pipelines in human medicine[5].
● Formulation choice: We opted for shRNA rather than single-dose siRNA. shRNA can be continuously expressed inside cells, reducing the need for frequent interventions and better fitting potential household use scenarios[16].
● Safety considerations: We limited Fel d 2 (cat serum albumin) to in-vitro verification only because of its documented cross-reactivity with porcine albumin (the ‘pork-cat syndrome’[17]. Excluding Fel d 2 from early product targets aligns with our animal-welfare-first risk policy. This avoids potential risks of physiological disruption and cross-reactivity associated with “pork-cat syndrome.”
How We Made RNAi Verifiable in Practice
Once we identified RNAi as our core technical pathway, our first challenge was how to validate it within the scope of the iGEM competition. Our research showed that the two commonly used feline lines (CRFK and F81), which are kidney/fibroblast-derived and not known to express salivary/skin allergens, showed no detectable endogenous Fel d 1/2/4/7 in our hands or in accessible reports, so direct knockdown readouts were not feasible for us within season constraints.
To address this, we visited cell suppliers and academic labs. Discussions with Prof. Chuanxu Yang (Shandong University) and experts at Lingzhu Laboratory gave us an important insight: build a substitute reporter system. Lingzhu provided a modified Saccharomyces cerevisiae strain with a complete RNAi pathway. Using this platform, we built a GFP reporter system: allergen mRNA fragments were fused with GFP, and when shRNA worked, GFP fluorescence decreased—providing a clear readout of silencing effects.
Ultimately, we designed 15 shRNAs across 5 targets (Fel d 1 CH1, Fel d 1 CH2, Fel d 2, Fel d 4, Fel d 7). Plasmids were produced in E. coli and introduced into the yeast GFP system. In several constructs, we observed significant GFP signal reduction, demonstrating stage-level success.
The value of this system lies in its ability to avoid the ethical and technical difficulties of mammalian cells, while preserving the core RNAi validation logic. In the future, other iGEM teams can also reuse this approach to quickly and safely test RNAi in a eukaryotic yeast system.
How Stakeholder Feedback Shaped Our RNAi Pathway
● Clinicians / Companies: Emphasized the importance of “short-term perceptibility” and “long-term safety.” Existing antibody-based cat food requires continuous use, with rebound effects upon discontinuation—limiting user experience. → We therefore built “perceptible short-term effect” and “reversible, stoppable use” into RNAi’s design constraints.
● Regulators / Policy experts / Investors: Widely identified delivery as the greatest bottleneck—there is no established paradigm for delivering RNA into salivary or sebaceous glands[18]. → In our Human Practices work, we evaluated physical transitional solutions such as transdermal or oral sprays, and incorporated a milestone-based roadmap (in vitro → animal studies → long-term safety) into our planning.[19][20]
Summary
Why RNAi: It reduces the production of Fel d allergens at the source (the mRNA level). It is reversible[14], safe, offers multi-target coverage[15], and has already been validated through drug-based clinical feasibility pathways[5].
Our contribution: Under the condition that “commonly used feline cell lines lack endogenous expression,” we established a yeast-based GFP reporter system with an RNAi framework, completed primary screening of 15 shRNAs, and provided a low-risk pathway for interim validation[16].
Outstanding issue: RNAi delivery remains the greatest bottleneck. Currently, there is no successful paradigm targeting the salivary or sebaceous glands[18]. This will be the key direction of our future efforts.
Table 1: Why not Gene Editing / Antibodies / Only Environmental Control?
| Approach | Advantages | Limitations | Our Conclusion |
| Gene editing cats | One-time, permanent elimination of targets (e.g., Fel d 1 CH2 chain) | High technical threshold; ethical/regulatory risks; costly; difficult to popularize in the short term | Not suitable as a scalable solution |
| Antibody-based cat food/wipes | Already commercially available; some studies show reduction of Fel d 1 | Requires continuous long-term use; rebounds after discontinuation; weak short-term user perception | Insufficient to achieve stable "source reduction” |
| Air purification/environmental management | Can reduce airborne allergen concentration | Cannot stop continuous secretion in cats; only addresses symptoms, not root cause | Only suitable as a supplementary measure |
| Human-side drugs/immunotherapy | Can relieve symptoms; established clinical pathways | Strong dependence; potential side effects or high cost (e.g., IgE antibodies); does not reduce production in cats | Only relieves individual symptoms; cannot resolve the fundamental issue of human–cat cohabitation |
→ Our choice: RNAi, to reduce allergen production at the source in cats.
Table 2: How We Implement RNAi
| Step | Our Approach | Contribution & Significance |
| 1. Target selection | Designed multi-target shRNAs against Fel d 1, Fel d 4, and Fel d 7 (major allergens). Fel d 2 used only for functional validation, not included in early product development. | Ensures scientific validity of targets while considering safety. |
| 2. RNAi form selection | Adopted shRNA, which can be continuously expressed in host cells, reducing the need for repeated interventions. | Better suited for future household application scenarios. |
| 3. Validation model | Common feline cell lines (CRFK/F81) lack endogenous expression → shifted to engineered Saccharomyces cerevisiae with an RNAi system; built an mRNA–GFP reporter system. | Innovative, low-risk; suitable for a high school iGEM team. |
| 4. Interim results | Introduced 15 shRNAs into yeast; some constructs showed significant GFP signal reduction. | Demonstrated interference effectiveness; established a reusable validation platform. |
| 5. Next steps | HP research advancing in parallel on delivery methods (transdermal/oral spray) and compliance simulation pathways. | Provides a roadmap for future translation and commercialization. |
→ Our innovation: We established a “RNAi yeast GFP reporter system” and simultaneously advanced target safety, delivery feasibility, and compliance strategy through HP, ensuring both scientific rigor and practical applicability.
Why Consider Commercialization?
Why bring the problem from the “laboratory” into “everyday life”?
● Real unmet need: Team survey (July 2025, n=703) showed that under the condition of “not affecting cat health,” 54.9% of respondents were willing to try allergen-reducing approaches. In offline interviews, about one-third of families reported allergic symptoms in cohabitation, and many people were reluctant to give up living with cats.
● Gap in existing solutions: Current methods—drugs, air purifiers, antibody cat food—require long-term continuous use, show weak short-term effects, and easily rebound after discontinuation, leading to poor compliance[21].
● Goal of technology for all: If the RNAi pathway can safely and reversibly reduce allergens at the source, we hope it will not remain only in papers or a single competition, but truly enter households and help real people.
What We Learned From Stakeholders (→ Changes in Our Decisions)
1) Pet Food Companies (Keson Biotech, Aug 2, 2025; Petty Pet Food, Aug 8, 2025)
What we heard:
● Users more easily accept forms like snacks/cat sticks/additives; short-term perceivable effects are key to repeat purchase.
● Current single/multi-antibody products require continued use; rebound occurs after discontinuation; additives face storage and regulatory hurdles.
● Price premium tolerance for functional products is around 30–40%, but must come with “perceivable change.”
How we changed:
● Defined three main constraints for product design: onset time, user perceptibility, monthly cost.
2) Doctors & NGOs (Zhejiang University 2nd Hospital, Dr. Yao, Aug 6, 2025; Lucky Stray Cat / Beijing NGO, Aug 7, 2025)
What we heard:
Drugs, desensitization, and biologics each have limitations; long-term safety and compliance remain major challenges[7].
Abandonment risk is higher when children have allergies; pre-adoption education and risk communication are essential.
How we changed:
Added “pre-adoption risk education + FAQ” to HP outreach.
Product design follows principles of non-gene-editing, reversible, and safety-first.
3) Regulatory & Policy Experts (Weijiexin Biotech, Aug 14, 2025)
What we heard:
● Regulatory classification depends on ingredients and claims; if deemed a veterinary drug, long-term safety data and systematic registration will be required.
How we changed:
● Established “evidence milestones” for stepwise validation before registration: in vitro reporter → animal safety/efficacy → formulation & delivery → registration dossier.
● Conducted compliance simulations with multi-scenario evaluation (“food additive / veterinary drug / medical product”).
4) Investors & Industry Observers (Sept 15, 22, 25, 2025 – Liu Chengmin, Xu Jingsong, Hillhouse Capital VP)
What we heard:
● Target users should be families with severe, persistent symptoms and strong unmet need.
● Delivery remains the biggest bottleneck (no mature paradigm yet for targeting salivary/sebaceous glands).
● Suggested supplementing with RNA drug development history and human precedents to enhance credibility[22]. Short-to-mid term: evaluate transdermal/oral spray as transitional solutions.
How we changed:
● Added “transitional delivery” evaluation branch to our roadmap.
● Prepared concise materials on “RNAi safety and precedents,” emphasizing reversibility and multi-target advantages.
Info Card A: “Minimum Viable Hypothesis” for Users & Market
| Dimension | What We Learned | Impact on Product Design |
| Target users | Families with severe/continuous symptoms still cohabiting with cats | Define “short-term perceivable effect” indicators |
| Form preference | Snacks/cat sticks/additives are more acceptable | Prioritize food-based prototypes, keep spray/transdermal as backup |
| Price acceptance | +30–40% premium acceptable if there is clear effect | Set monthly spending cap + “time-to-effect” window |
| Safety & ethics | non-gene-editing, friendly to cat’s internal homeostasis | Exclude Fel d 2 from early targets; emphasize risk communication |
| Regulatory path | Classification depends on ingredients/claims | Prepare multi-scenario compliance simulations & dossier templates |
| Delivery bottleneck | No paradigm yet for salivary/sebaceous targeting | Explore physical delivery transition; gather receptor data |
Info Card B: Risk–Response Matrix
| Risk | Possible Outcome | Our Response |
| Low delivery efficiency | No significant reduction of allergens in vivo | Parallel evaluation of transdermal/oral spray; small-scale studies on distribution & pharmacodynamics |
| Safety/off-target | Potential effects on cat physiology | Multi-target but strict screening; Fel d 2 only for in vitro testing; tiered safety trials |
| Poor compliance | Users discontinue → unstable effect | Design for short-term perceivable effect; provide clear “use vs. stop” curves |
| Regulatory uncertainty | Project blocked or delayed | Pre-prepare multi-pathway dossiers; maintain dialogue with regulators |
| Market substitutes | Low-cost drugs/air purifiers as alternatives | Emphasize “source reduction + reversible safety” differentiation; control monthly cost |
Our Phased Milestones (“Validate First, Register Later”)
● Stage 0 (Completed): Built RNAi–yeast GFP reporter system; initial screening of 5 targets × 3 sequences → multiple effective shRNAs identified.
● Stage 1 (Validation): Further functional validation in cell/tissue surrogate models (e.g., homologous reporters, protein quantification); preliminary feasibility tests for transdermal/oral RNA delivery.
● Stage 2 (Safety & Formulation): Animal safety + preliminary efficacy; determine lead formulation (snack/additive priority); establish “use–discontinue” curve.
● Stage 3 (Regulatory Prep): Complete core registration dossiers + long-term follow-up plans; parallel user pilot studies (within regulatory approval scope).
Note: As a high school iGEM team, our season focus remains on validation systems, data, and compliance modeling; animal-related work will be done with licensed institutions/labs.
Open Questions (→ To Be Continued)
● Can we identify highly expressed receptors/channels in feline salivary/sebaceous glands to improve targeting?
● How to optimize RNA stability & efficiency in transdermal delivery (encapsulation, chemical modification, penetration enhancers)?
● For severe users, how do we refine our value proposition vs. low-cost drugs/purifiers, and define cost ceiling?
● What lessons (failures/successes) from similar projects (e.g., human RNAi drug delivery with LNPs) can be repurposed[22]?
Conclusion
For us, commercialization is not the “end point of financing,” but the starting point of responsibility:
● Using real-world feedback to reshape technology and products;
● Building trust with transparent, verifiable data;
● Bringing RNAi science into households in a safe, reversible, and accessible way, for those who truly need it.
Alignment with Sustainable Development Goals (SDGs)
This project contributes to several UN SDGs by addressing both human health and animal welfare:
● SDG 3: Good Health and Well-being – By aiming to reduce allergic disease at the source, we support safer cohabitation and improved quality of life for millions of people worldwide.
● SDG 12: Responsible Consumption and Production – By providing an alternative to continuous drug use or rebound-prone antibody products, our approach emphasizes sustainability and responsible innovation.
● SDG 15: Life on Land – By focusing on safe, cat-friendly solutions, we reduce abandonment risks and promote harmonious human–animal relationships.
Through stakeholder collaboration and responsible design, our project also supports SDG 9 (Innovation) and SDG 17 (Partnerships).
Interviews & Engagement Log
(Note: This page only lists key points of each interview. All records have been archived within the team. The relevant content has been aligned with the interviewees and is only used for internal execution and external (HP/Wiki) filing.)
2025-04｜Expert Discussion on Project Initiation (Shandong University)
Meeting Experts: Prof. Li Qiang, Prof. Yang Chuanxu
Identity/Organization: University Tutors ｜ RNAi & RNAi Delivery Systems
1. Discussion Summary
In this project initiation discussion, the two experts focused on the feasibility of RNAi, the choice between siRNA and shRNA, and the translational value of delivery systems. The experts noted that RNAi, as an “upstream emission reduction” strategy, can achieve reversible inhibition without altering the genome, offering both technical and ethical advantages. At the molecular strategy level, shRNA’s sustained expression is considered more suitable for early-stage research. Although delivery is not currently a primary task for the iGEM experiments, it was emphasized as a critical bottleneck for future translational applications and should be incorporated into long-term development planning.
2. Main Conclusions
● The RNAi approach is feasible, with reversibility and safety advantages.
● shRNA provides more stable and continuous expression compared to short-acting siRNA, and is recommended as the research focus.
● Delivery systems (especially LNPs) will be the key to future translational applications, but resources need not be invested at the iGEM stage; it can instead be presented as an important HP topic.
3. Route Adjustment
● Establish RNAi → shRNA as the core technical route.
● Focus iGEM experimental stage on molecular-level knockdown validation.
● In HP, highlight the perspective that “delivery is the critical bottleneck for future translation,” showing foresight and responsibility for long-term application.
4. Changes We Made
● Defined shRNA as the Phase I research focus to avoid resource dispersion.
● Shifted delivery from a current experimental focus to a long-term translational planning focus.
● Highlighted in HP: “RNAi is reversible, safe, and non-gene-editing,” and “delivery is the key future challenge.”
2025-04｜Technical Consultation with Cell Supplier (Zhongqiao Xinzhou)
Identity/Organization: Cell supply & technical support
Purpose: Assess feasibility of using cat cell lines directly for target validation
We Heard
● Common cat cell lines (CRFK, F81) do not endogenously express Fel d 1/2/4/7.
● Building a stable cell line via AAV is unrealistic for a high school team in terms of time/conditions.
We Changed
● Abandoned “direct validation in cat cell lines.”
● Shifted towards exploring alternative validation systems.
We check the availability of cats' cells with professionals of Zhongqiao Xinzhou.
2025-06｜Alternative Validation System (Lingzhu Lab)
Identity/Organization: Collaborator ｜ Synthetic Biology R&D Platform
Discussion Theme: Building an RNAi reporter system in a eukaryotic background
Purpose: Verify shRNA design effectiveness and create a reusable rapid screening platform
Discussion Summary
● Partner can provide engineered S.cerevisiae strains with RNAi mechanisms for exogenous fragment silencing.
● Suggested coupling target mRNA fragments with GFP signal, using GFP reduction as a readout.
● Emphasized plate reader–based fluorescence detection as a straightforward way to evaluate inhibition efficiency, suitable for batch screening.
Core Conclusions
● Yeast–GFP RNAi reporter system can deliver results within days, enabling multi-target evaluation.
● Simple to operate, intuitive readouts, efficient for pre-mammalian screening.
● Standardized workflow (transformation → culture → fluorescence detection → data comparison) ensures reproducibility.
We Changed
● Established a GFP-RNAi yeast-based reporter system.
● Initial screening: 5 targets × 3 shRNAs = 15 candidates tested in platform.
● Detection: plate reader fluorescence measurements, no fixed inhibition threshold required.
● Application: rapid iGEM-stage evaluation tool; top candidates later validated in cat/mammalian cells.
2025-07｜Academic Conference Exchange (IEEE 3M NANO)
Identity/Organization: Prof. Li Qiang & Prof. Yang Chuanxu (Shandong University); Dr. Dong Mingdong (Aarhus University)
Purpose: Midterm report, receive optimization suggestions
We Heard
● Recommend testing combinations of multiple shRNAs to enhance silencing efficiency.
● Technical route and milestones are clear, with room for iteration.
We Changed
● Added evaluation of combinational shRNA interference in later stages.
2025-07｜Public Survey (703 Valid Samples)
Type: Public attitudes & needs assessment
Purpose: Scale, willingness, and concerns evaluation
We Heard (Key Questions)
● Q2 Allergic / possible / unsure: 64.9% combined.
● Q3 Interest in “allergen reduction technology”: 48.0% very interested.
● Q4 Acceptance of “RNAi (non-gene-editing)”: 34.0% acceptable.
● Q5 If cat health ensured: 54.9% willing to use.
We Changed
● Reinforced messaging on safety and animal welfare.
● Emphasized “non-gene-editing & reversible” in outreach materials.
Survey responses & statistical summary (see earlier section).
2025-08｜Industry Interviews (Zhejiang Kesheng 08/02; Petty Pet 08/08)
Identity/Organization: Pet food companies
Purpose: Validate product form, pricing, and user experience
We Heard
● Users prefer treat/snack/additive formats.
● Existing antibody-based products require continuous use, with rebound upon withdrawal.
● Short-term perceivable effect drives repurchase; 30–40% price premium acceptable if noticeable change guaranteed.
We Changed
● Prototype direction prioritizes snack/additive forms.
● Defined three design constraints: onset time, perceptibility, monthly cost.
2025-08-04｜Technical & Market Consultation (Dingchi Biotech, Dr. Li)
Identity/Organization: Pet functional product R&D (e.g., egg yolk IgY)
Purpose: Learn from existing anti-allergy approaches & validation methods
We Heard
● ELISA can quantify salivary Fel d1 (high cost).
● Polyclonal antibodies can reduce ~70% within 3 weeks but rebound upon withdrawal.
● Fel d 2 (serum albumin) unsuitable as an early-stage product target.
● RNAi must resolve delivery & cost; semi-annual delivery suggested as a scenario.
We Changed
● Restricted Fel d 2 to in vitro validation only, not first product release.
● Planned ELISA for later-stage quantification.
● Incorporated “delivery frequency/cost” into commercialization feasibility.
2025-08-05｜Academic Input (Yangzhou University, Prof. Yuan)
Identity/Organization: Cat gene-editing researcher
Purpose: Discuss Fel d 1 CH1/CH2 site conservation & safety
We Heard
● Academic advances and potential risks of CH2 editing.
● High ethical/regulatory hurdles for gene editing.
We Changed
● Excluded gene-editing commercialization; adhered to reversible RNAi path.
Note: This is a telephone interview.
2025-08-06｜Clinical Perspective (Dr. Yao, 2nd Affiliated Hospital of Zhejiang University)
Identity/Organization: Allergy clinician
Purpose: Human-side treatment effectiveness, compliance, side effects; necessity of cat-side “upstream reduction”
We Heard
● Drugs, desensitization, and biologics each have long-term burdens.
● Recommend paying attention to approval pathway and long-term safety.
● Pre-adoption screening/education important.
We Changed
● Added “evidence-based compliance milestones” in HP.
● Designed pre-adoption risk education + FAQ.
2025-08-7｜CCIC – China iGEMer Community Conference
Identity/Organization: CCIC organizing committee; multiple iGEM HS & UG teams (plenary + posters)
Purpose: Project presentation; peer review on HP framing, survey design, and validation strategy
We heard
● The HP chapter should first argue the necessity of the project before moving into the technical plan; link together “cohabitation pain points → gaps in existing solutions → demand evidence” into a closed loop.
● Delivery must be identified as the greatest uncertainty, listed in HP as an open question and milestone, rather than mentioned only in the experimental section.
● The survey page should openly provide sampling and bias explanations, along with the original wording of key questions and statistical methods, to allow external verification.
● External communications should foreground safety and animal welfare information, paired with clear explanations of “non-gene-editing / reversibility.”
We Changed
● Reorganized HP: Necessity → Gaps in existing solutions → Design requirements, then transitioned into the rationale for choosing RNAi.
● Added sections in HP: Design Requirements and Open Questions (delivery, long-term safety).
● Improved survey presentation: added sampling notes, original question text, statistical methods, and a downloadable summary.
● Established follow-up collaborations with BNDS-China (for education/HP format exchange) and SZU-China (for RNAi technical detail sharing).
2025-08-07｜NGO & Adoption Agency (Lucky Cat NGO / Beijing local NGOs)
Identity/Organization: Rescue & adoption platforms
Purpose: Understand abandonment risks & education pain points
We Heard
● ~1/3 of households reported allergy among family members.
● Abandonment risk higher with allergic children; front-end education more effective.
We Changed
● Produced pre-adoption education materials; emphasized “cat-friendly” + safety/reversibility in goals.
2025-08-14｜Industry Observation (Zhihu Contributor “Yunshan”)
Identity/Organization: Science communicator & industry observer
Purpose: Market scale, user acceptance, competitor comparison
We Heard
● Cat ownership is large and rapidly growing in China.
● Gap between antibody-based cat food claims and actual effects.
● RNAi half-life, chemical modifications, and delivery are key.
We Changed
● Added RNA drug development history and precedents to materials.
● Pre-researched stabilization strategies (chemical modification/encapsulation).
2025-08-14｜Regulatory & Industry Practice (Weijiexin Biotech Site Visit)
Identity/Organization: Protein engineering & veterinary drug registration
Purpose: Map regulatory path from claims to composition & documentation
We Heard
● Veterinary drug path requires systematic safety data + long-term follow-up.
● Should prepare multi-scenario compliance plans (food additive / veterinary drug / pet product).
We Changed
● Set “validate first, file later” evidence milestones.
● Built compliance checklist & documentation templates.
2025-08-28 | Inter-team Exchange (SZU-China iGEM Team)
Identity/Institution: iGEM Team (RNAi Agricultural Direction: RNA Biopesticide for Citrus Aphids)
Purpose: To exchange experiences in RNAi molecular design, production and delivery pathways, as well as cost and regulatory aspects; to learn from cross-domain implementation practices to feed back into this project.
We Heard
● Project Positioning: RNA biopesticide targeting citrus aphids, planned to be delivered via trunk injection; exploring carriers such as VLP/nanoliposomes/cationic liposomes.
● Production Pathways: In Vitro Transcription (IVT) RNA has high purity, suitable for early verification; fermentation/bacterial production is more economical but requires stricter purification and residue control.
● Cost and Regulation: There are significant differences in regulatory requirements between agricultural RNAi and veterinary/pet products; large-scale production can dilute costs, but stability/cold chain are key cost items.
● Target Safety: Cross-species off-target effects need to be evaluated; caution should be exercised when dealing with animal physiological key proteins (enlightening us: Fel d 2).
We Changed
● Incorporate "IVT vs. Fermentation Production" into the internal evaluation matrix: prioritize IVT in the R&D screening stage, and evaluate the economy and process control of the fermentation route in the long term.
● Strengthen "delivery + stability" as the core bottleneck in the HP roadmap, and record VLP/nanoliposomes as alternative technical pathways.
● Continue to adhere to the safety trade-off of "Fel d 2 only for in vitro verification".
● Add "comparison points of regulatory differences between agricultural RNAi and veterinary drugs" in the compliance section for commercial scenario analysis.
2025-09-13｜Inter-school Exchange
Identity/Orgs: BNDS-China host; participating teams incl. BNDS-China, UCAS, RDFZ-China, Keystone, others
Purpose: Share project; compare HP/Education formats; exchange technical choices
We heard
● Campus talks + FAQ handouts are effective for myth-busting and safety communication.
● Teams emphasize adding explicit safety disclaimers and “non-medical advice” statements in outreach.
● Cross-project comparisons sharpened awareness of product-safety controls.
We changed
● Built a campus talk kit (slides/FAQ) and scheduled internal talks.
● Revised outreach scripts to put safety & reversibility up front; aligned with our HP education goals.
Evidence: internal slide deck + FAQ
2025-09-15｜Investor Interview (Angel Investor Liu Chengmin)
Identity/Organization: Investor
Purpose: Market positioning, milestones, funding rhythm
We Heard
● Focus on high-need severe cases.
● Strengthen team credibility and “multi-target broad-spectrum” differentiation.
● Funding stages should align with in vitro → animal → formulation → registration progression.
We Changed
● Simplified pitch deck; highlighted reversible upstream intervention & evidence milestones.
● Drafted 5-year roadmap with staged funding allocation.
2025-09-22｜Investor Consultation (Angel Investor Xu Jingsong)
Identity/Organization: Investor
Purpose: Feasibility & collaboration pathways
We Heard
● High school teams need professional advisors for stronger execution.
● Recommended partnerships with universities/institutions for animal studies.
● Early-stage financing scale/valuation should be adjusted conservatively.
We Changed
● Began forming advisory board.
● Integrated cross-institution collaborations into development plan.
2025-09-25｜Joint Industry & Capital Evaluation (Hillhouse Capital VP & SynBio Investors)
Identity/Organization: Investment institutions
Purpose: Market focus & delivery transition plans
We Heard
● Avoid broad “pet market” estimates; focus on severe allergy cases.
● No precedent for salivary gland/sebaceous gland delivery; evaluate transdermal/oral spray as transition approach.
● Include precedents of marketed RNA drugs in external communications.
We Changed
● Added validation branch for “physical delivery transition.”
● Integrated RNA drug history & precedent module into presentations/Wiki.
2025-07｜Follow-up Survey (Education-Focused)
Type: Educational survey to address misconceptions
Purpose: Identify public misunderstandings about cat allergies and RNA
We Heard
● Many respondents mistakenly identified “cat hair” as the allergen source.
● Lack of awareness that RNAi is non-gene-editing.
We Changed
● Produced FAQ, infographics, and short video scripts for adoption agencies & communities.
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