STRC Research

hypb-cochlear-immune-and-lnp-delivery

6 min read

GROUNDING — cochlear immune environment, and cochlear LNP-mRNA delivery efficiency

Source A — cochlear immune capacity (channel ii)

  • Source: Hu BH, Zhang C, Frye MD. “Immune cells and non-immune cells with immune function in mammalian cochleae.” Hear Res 2018 May;362:14-24. doi:10.1016/j.heares.2017.12.009. PMID 29310977, PMCID PMC5911222.
  • Accessed: 2026-08-21
  • Exact queries:
    1. WebSearch cochlea immune privilege blood-labyrinth barrier antigen presenting cells organ of Corti absence dendritic cells
    2. curl -s ".../esearch.fcgi?db=pubmed&term=Immune+cells+and+non-immune+cells+with+immune+function+in+mammalian+cochleae&retmax=3&retmode=text" → PMID 29310977
    3. curl -s ".../efetch.fcgi?db=pubmed&id=29310977&rettype=abstract&retmode=text"

Verbatim (abstract)

“The cochlea has an immune environment dominated by macrophages under resting conditions. When stressed, circulating monocytes enter the cochlea. These immune mediators, along with cochlear resident cells, organize a complex defense response against pathological challenges. Since the cochlea has minimal exposure to pathogens, most inflammatory conditions in the cochlea are sterile. Although the immune response is initiated for the protection of the cochlea, off-target effects can cause collateral damage to cochlear cells. … we describe the composition and distribution of immune cells in the cochlea and suggest that phenotypic and functional characteristics of macrophages have site-specific diversity.”

Secondary (WebSearch synthesis, same query, accessed 2026-08-21; SECONDARY weight)

“The inner ear, including the cochlea, has long been considered an ‘immune-privileged’ site, an assumption primarily based on the blood-labyrinth barrier (BLB) … over the past five years, cochlear immunology has experienced a paradigm shift, challenging the long-held perception of the inner ear as an ‘immune-privileged’ site.”

“the cochlea’s intricate local immune system comprises resident macrophages, T lymphocytes, and dendritic cells, in conjunction with the regulatory blood-labyrinth barrier.”

“A striking finding in cochlear immunology is that the organ of Corti lacks immune cells despite the fact that sensory cells in this region are susceptible to various pathological insults.”

“Perivascular melanocyte-like macrophages (PVM/Ms) have been identified in the stria vascularis, and these dedicated antigen-presenting cells also control vascular contraction and permeability.”

Evidential weight

  • STATES (primary): cochlear resting immune environment is macrophage-dominated; inflammation there is mostly sterile; immune activation in cochlea carries an off-target collateral-damage risk to cochlear cells.
  • STATES (secondary): APCs (dendritic cells, PVM/Ms) exist in the cochlea, but the organ of Corti — where outer hair cells live — lacks immune cells. The “immune privilege” framing is partially outdated; the accurate statement is compartmentalised immunity with the sensory epithelium itself immune-cell-poor.
  • This is grounding about the cochlear immune environment. It is NOT evidence that any immune mechanism could substitute for STRC protein. The bridging argument in MODERNA.md is explicitly labelled inference.

Source B — cochlear LNP-mRNA delivery efficiency (channel iii)

  • Source: STRC vault, hypotheses/h06-mrna-therapy/phases/STRC h06 Parameter Provenance Audit 2026-04-25.md and models/mrna_lnp_pkpd_integration_v2_ohc_tropism.py.
  • Accessed: 2026-08-21
  • Exact queries: grep -rn "PMC5784267" . from ~/Missions/STRC; then sed -n '100,145p' on the audit note and sed -n '50,75p' / sed -n '190,210p' on the script.

Verbatim (vault, audit note)

“Verdict: ⚠ NO PRIMARY PAPER. Literature-flagged as aspirational.”

”- No published paper demonstrates LNP-mRNA delivery efficiency to OHCs ≥ 5%.

  • Closest precedent: Gao et al. 2018 Nature (PMID 29258297; PMC5784267) — lipid-RNP (NOT LNP-mRNA), ~0.92% indel in organ of Corti; this backs the 0.8% untargeted floor, not the 20% targeted scenario.
  • Wang et al. 2018 (PMC6241721): A666 prestin-peptide on PEG-PLA NP (NOT LNP-mRNA); demonstrates OHC drug protection but no OHC% transfection reported.
  • The 5% ‘cochlear-tropic’ and 20% ‘OHC-targeted’ values are correctly flagged as engineering targets not yet achieved”

Verbatim (vault, script)

def cochlea_fold(f_tx: np.ndarray, eff_ohc: float) -> np.ndarray: return eff_ohc * f_tx + (1.0 - eff_ohc) * 1.0

”# LNP_UNTARGETED = 0.008 remains ⚠ unsourced specifically; no primary paper

pins LNP-mRNA OHC efficiency. Closest precedent: Gao 2018 Nature (PMID

29258297; PMC5784267) reports ~0.92% indel in organ of Corti using

lipid-RNP (not LNP-mRNA). LNP_OHC_TARGETED = 0.20 is ASPIRATIONAL —

per LNP Cochlear Tropism Literature Scan 2026-04-22, no published paper

demonstrates LNP-mRNA OHC efficiency ≥ 5%.”

HILL_K = params["hill_km"] # ⚠ CIRCULAR FIT (no OHC splicing dose-response) MAX_BOOST = params["max_boost"] # ⚠ CIRCULAR FIT

Verbatim (vault, reviews/STRC Cure-Route Audit mRNA vs De-Novo Binder 2026-08-20.md)

“The identity is cochlea_mean = eff*f_tx + (1-eff)*1, i.e. <= 1 + eff*(max_boost-1) … This is a weighted-average tautology: untreated OHCs contribute exactly 1.0 by definition, so the population mean is pinned near 1 whenever delivery is low, regardless of per-cell potency. Delivery efficiency is the binding constraint; potency cannot substitute for it. That part is arithmetic and no literature can overturn it.”

Table: eff 0.01 → 1.02x; eff 0.03 → 1.06x; eff 0.05 → 1.10x; eff 0.20 → 1.40x (base max_boost=3.0).

“The frequently-cited ‘1.8x ceiling at 20% delivery’ requires max_boost = 5.0 — the top corner of the sensitivity grid … The base-model number is 1.40x … The ‘1.02-1.06x at realistic 1-3%’ figure is correct as stated.”

Source C — current inner-ear LNP literature (channel iii, external check)

  • Accessed: 2026-08-21
  • Exact query: WebSearch lipid nanoparticle mRNA delivery inner ear cochlea hair cell transfection efficiency round window 2024 2025

Reported findings (SECONDARY — search-result synthesis)

“An SS-cleavable proton-activated lipid-like material (ssPalm), a neutral lipid nanoparticle loaded with mRNA, showed that LNPssPalm carrying brain-derived neurotrophic factor (BDNF) mRNA was suitable for treatment of inner ear diseases, preventing degeneration of spiral ganglion neurons (SGNs).” — delivered through the round window niche in guinea pig cochleae; target cell is the spiral ganglion neuron, not the outer hair cell.

“PEGylated PLA nanoparticles coated with the A666 peptide show greater targeting efficiency than untargeted nanoparticles, with increased localization in outer hair cells and modiolus. Additionally, PEGylated liposomes coated with a prestin-targeting peptide present improved cochlear targeting with both TdTomato and carboxyfluorescein being expressed in outer hair cells.”

“In 2024, an ionizable cholesterol analog, 3β[L-histidinamide-carbamoyl] cholesterol (Hchol), was developed as a substitute for cholesterol in LNP assembly, with results showing that the imidazole moiety promotes endosomal escape and increases LNP delivery potency and stability.”

“The search results show active research in LNP-based inner ear therapeutics, though specific transfection efficiency percentages for cochlear hair cells via round window delivery were not prominently featured in these results.”

Evidential weight

  • STATES: inner-ear LNP-mRNA work exists and is a separate literature — round-window / intracochlear administration, largely SGN-directed, from groups unconnected to the intismeran programme.
  • DOES NOT STATE anywhere retrieved: any percentage OHC transfection efficiency for LNP-mRNA. The external search independently reproduces the vault’s null finding. No efficiency figure for OHC LNP-mRNA is grounded, so none is asserted.
  • DOES NOT STATE: any connection between intismeran-associated LNP chemistry and inner-ear delivery. I searched for one and found none.

Source D — STRC protein size

  • Source: STRC vault, .../deep-research/DR3_cro_wet_lab_handoff.md, accessed 2026-08-21 via grep -rn "1775" sources/ notes/ hypotheses/.

“stereocilin (STRC) is a massive 1775-amino-acid extracellular protein attached to the …”

Verbatim (vault, Cure-Route Audit — patient-side ceiling)

“Paternal contribution is zero. Allele-specific rescue therefore has a hard cap: f_AS = 0.5*[f_mat + f_PC*(1-f_mat)] <= 0.50 of diploid-normal protein per OHC, at f_PC = 1.”

“clearing threshold_fold = 2.0 requires eff ~= 0.50 at base max_boost=3.0 (or ~=0.25 at the grid corner). Both are model contours, not measured requirements, and both sit an order of magnitude above the realistic 0.01-0.03.”

Graph View