Science · Gene Therapy

AAV9: доставка генов в опухоли

Вектор, который carries NKG2D-LIF6 в клетки. Та же family что Zolgensma, другой payload.

Что такое AAV?

Adeno-associated viruses — небольшие, non-pathogenic вирусы, engineered в workhorse delivery vehicle для gene therapy. Они infect human cells и deliver DNA payload без causing disease — zero replication, zero integration в host genome (mostly), zero significant immune pathology at therapeutic doses. FDA approved несколько AAV-based gene therapies, including Luxturna (AAV2 для inherited blindness) и Zolgensma (AAV9 для spinal muscular atrophy).

AAV приходит в many serotypes — AAV1, AAV2, AAV5, AAV8, AAV9 и т.д. — каждая с different tissue tropism. Какой serotype выбираешь — определяет, какие cells твой payload reaches. AAV2 tends to transduce liver и retina. AAV8 has strong liver tropism. AAV9 crosses blood-brain barrier и has broad tissue distribution.

Почему AAV9?

Мы выбрали AAV9 как starting vector для NKG2D-LIF6 по нескольким причинам:

• Broad tissue tropism. Solid tumors могут occur почти в любой ткани. Нужен vector, который doesn't restrict нас к одному органу. AAV9 имеет documented transduction across muscle, heart, liver, lung, brain и других тканей (Foust et al. 2009, Nature Biotechnology).
• Clinical precedent. Zolgensma (onasemnogene abeparvovec) — AAV9 gene therapy, approved для SMA в детях. Установила regulatory pathway, manufacturing playbook и safety database для systemic AAV9 delivery в humans.
• Packaging capacity. AAV имеет roughly 4.7 kb packaging limit. Наш NKG2D-LIF6 construct — 2,123 bp, comfortably под limit с room для promoter, ITRs и regulatory elements.
• Manufacturing maturity. AAV9 может produced multiple CDMOs at research и GMP grade. Costs fell significantly since 2019.

AAV9 — working assumption, а final decision. In vivo program включает serotype screen. Если different serotype shows better tumor tropism или lower immunogenicity в наших models, переключимся.

Как это работает с NKG2D-LIF6

NKG2D-LIF6 construct packaged между AAV2 inverted terminal repeats (ITRs) и driven constitutive promoter. Когда AAV9 particle infects cell, uncoats в nucleus, transgene expressed как episomal DNA. Cell starts producing NKG2D-LIF6 chimeric protein.

В tumor cells, expressing MICA/MICB — NKG2D ectodomain portion chimera binds эти stress ligands, и LIF6 effector portion translocates к mitochondria и triggers apoptosis. В healthy cells без MICA/MICB expression — construct expressed, но chimera has nothing to bind — поэтому kill mechanism stays inactive. Это tumor-restriction logic.

Известные limitations

AAV gene therapy имеет real limitations и мы upfront о них:

• Pre-existing immunity. Некоторые patients имеют neutralizing antibodies против AAV9 from prior natural exposure к wild-type AAV. Эти patients могут excluded или given immunomodulation first.
• Immunogenicity. AAV capsid может trigger T-cell responses, especially at high doses. Zolgensma patients receive corticosteroids для управления этим.
• Redosing. После first AAV9 dose, immune system typically generates strong anti-AAV9 antibodies, making second dose same serotype ineffective. По сути one shot.
• Hepatotoxicity. AAV9 имеет liver tropism наряду с broader distribution. High systemic doses caused serious liver toxicity в некоторых gene therapy programs. Dose-finding critical.
• Manufacturing cost. Несмотря на recent cost reductions, AAV manufacturing at GMP grade всё ещё expensive — roughly $100K-$500K per patient для systemic dosing.

Экономика shifts

Одна из reasons, why bootstrapped company может attempt это в 2026 — research-grade AAV manufacturing costs dropped substantially. В 2019, getting research-grade AAV9 at quantities sufficient для mouse studies easily cost $50K-$100K. К 2026, competition среди CDMOs — PackGene, Aldevron, Vector BioMed, Charles River — pushed research-grade costs down roughly an order of magnitude. Можно get small-scale research lot за few thousand dollars.

Это doesn't help с GMP manufacturing для human use, который всё ещё expensive. Но means pre-IND phase — proof-of-concept animal studies — теперь accessible team, который backed by $50M in venture capital. Это operating window Nightbox occupies.

Написано Артёмом Шакиным, founder Nightbox LLC. Published 2026-04-30. CC BY 4.0.