787 Synapse-localized γ-chain cytokine presentation enables single-dose, soluble cytokine–free T cell expansion in plate and G-Rex bioreactor formats with reduced manufacturing complexity and cost
Year: 2026
Type: conference-abstract
Abstract: Background Soluble γ-chain cytokines are essential for T cell expansion in adoptive cell therapy manufacturing. Repeated cytokine dosing 2 to 3 times per week drives high costs, labor burden, and donor-dependent variability. Frequent bulk cytokine delivery produces transient, non-physiologic signaling and fails to replicate immune synapse–localized cytokine presentation. Previous studies demonstrated that the programmable cellular interface (sbPCI™), which emulates immune synapse architecture and enables integration of γ-chain cytokines at defined density and organization, can reduce the need for exogenous cytokines. This study tests whether spatially programmed cytokine integration on sbPCI could sustain T cell expansion without repeated cytokine addition across bioreactor formats.Methods Ex vivo expansion using surface-programmed cytokines was evaluated. Qualified RBCs were modified with sbPCI displaying anti-CD3/CD28, anti-CD3/ CD28/ CD137 and cytokine(s) (IL-2, IL-7, IL-15, or combinations thereof) integrated at defined stoichiometry, densities and spatial configurations. PBMCs from 6 healthy donors were co-cultured with sbPCI in 24-well G-Rex and G-Rex 6M gas-permeable bioreactors. Soluble cytokine controls were dosed according to G-Rex recommended protocols while the cytokine-integrated sbPCI samples received no soluble or integrated cytokines after Day 0. The 24 well plates received cytokine 3x per week. Performance of integrated cytokines was analyzed via receptor activation (STAT phosphorylation), activation (CD25, Granzyme B), expansion (fold change), phenotype (CD45RA/ CD45RO/ CD62L/ CCR7/ CD25/ CD69 expression, exhaustion markers), and bioreactor metabolic profiles (glucose, lactate).Results Surface-integrated cytokines successfully substituted for repeated exogenous soluble cytokine addition. sbPCI-cytokine formulations induced dose-dependent STAT phosphorylation in both CD4 + and CD8+ T cells within 40 minutes and exhibited significantly higher activity compared to soluble cytokine. Activation of T cells was equivalent to soluble controls. Furthermore, sbPCI-cytokine formulations increased T cell fold expansion with both anti-CD3/CD28 and anti-CD3/ CD28/ CD137 activation. T cell phenotype at assay completion demonstrated a predominant CD45RO+ CD45RA− activated/memory profile with preserved CD62L positivity, and sustained CD25 and Granzyme B MFI comparable to soluble cytokine controls without reaching a terminal exhaustive state. Glucose and lactate monitoring defined manufacturing-relevant metabolic profiles. Successful implementation in 24-well G-Rex and G-Rex 6M bioreactors illustrates both feasibility for this technology in manufacturing and ability to translate high-throughput optimization during scale-up.Conclusions Synapse-localized cytokine presentation on sbPCI sustains T cell expansion, signaling, and memory phenotype with a single Day 0 dose. This eliminates repeated cytokine addition and reduces reagent consumption, labor, and donor-dependent variability. Translation to TIL, CAR, engineered TCR, and NK platforms will support a scalable, cost-reduced manufacturing paradigm for cell therapy.
Language: English
Topic: CAR-T cell therapy research
Subfield: Oncology
Field: Medicine
Domain: Health Sciences
Open Access status: gold
Estimated APC paid: $2,490
OpenAlex ID: W7225155350