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Biology subjects

Qureshi, K.

Publications and source records attributed to Qureshi, K..

3 recordsLinked to original sources

Modulation of antigen delivery and lymph node activation in non-human primates by saponin adjuvant SMNP

Saponin-based vaccine adjuvants are potent in preclinical animal models and humans, but their mechanisms of action remain poorly understood. Here, using a stabilized HIV envelope trimer immunogen, we carried out studies in non-human primates (NHPs) comparing the most common clinical adjuvant alum with Saponin/MPLA Nanoparticles (SMNP), a novel ISCOMs-like adjuvant. SMNP elicited substantially stronger humoral immune responses than alum, including 7-fold higher peak antigen-specific germinal center B cell responses, 18-fold higher autologous neutralizing antibody titers, and higher levels of antigen-specific plasma and memory B cells. PET-CT imaging in live NHPs showed that, unlike alum, SMNP promoted rapid antigen accumulation in both proximal and distal lymph nodes (LNs). SMNP also induced strong type I interferon transcriptional signatures, expansion of innate immune cells, and increased antigen presenting cell activation in LNs. These findings indicate that SMNP promotes multiple facets of the early immune response relevant for enhanced immunity to vaccination.

bioengineering↗

Visualizing lipid nanoparticle trafficking for mRNA vaccine delivery in non-human primates

mRNA delivered using lipid nanoparticles (LNPs) has become an important subunit vaccine modality, but mechanisms of action for mRNA vaccines remain incompletely understood. Here, we synthesized a metal chelator-lipid conjugate enabling positron emission tomography (PET) tracer labeling of LNP/mRNA vaccines for quantitative visualization of vaccine trafficking in live non-human primates (NHPs). Following i.m. injection, we observed LNPs distributing through injected muscle tissue, simultaneous with rapid trafficking to draining lymph nodes (dLNs). Deltoid injection of LNPs mimicking human vaccine administration led to stochastic LNP delivery to 3 different sets of dLNs. LNP uptake in dLNs was confirmed by histology, and cellular analysis of tissues via flow cytometry identified antigen-presenting cells as the primary cell type responsible for early LNP uptake and mRNA translation. These results provide insights into the biodistribution of mRNA vaccines administered at clinically relevant doses, injection volumes, and injection sites in an important large animal model for vaccine development.

bioengineering↗

Local delivery of cell surface-targeted immunocytokines programs systemic anti-tumor immunity

Cytokine therapies are potent immunotherapy agents but exhibit severe dose-limiting toxicities. One strategy to overcome this involves engineering cytokines for intratumoral retention following local delivery. Here, we develop a localized cytokine therapy that elicits profound anti-tumor immunity by engineered targeting to the ubiquitous leukocyte receptor CD45. We designed CD45-targeted immunocytokines (CD45-Cyt) that, upon injection, decorated the surface of leukocytes in the tumor and tumor-draining lymph node (TDLN) without systemic exposure. CD45-Cyt therapy eradicated both directly treated tumors and untreated distal lesions in multiple syngeneic mouse tumor models. Mechanistically, CD45-Cyt triggered prolonged pSTAT signaling and reprogrammed tumor-specific CD8+ T cells in the TDLN to exhibit an anti-viral transcriptional signature. CD45 anchoring represents a broad platform for protein retention by host immune cells for use in immunotherapy.

immunology↗