Fig. 8: Intranasal administration of NanoSTING limits transmission and viral replication in the nasal passage of contact hamsters exposed to the SARS-CoV-2 Omicron (B.1.1.529) VOC.

A Experimental setup: For group 1, we challenged groups of 8 hamsters each on day 0 with ∼3 × 10⁴ of SARS-CoV-2 Omicron VOC (B.1.1.529) and after 24 h cohoused index hamsters in pairs with contact hamsters (n = 8) for 4 days in clean cages. In group 2, we pre-treated the hamsters with 120 µg of NanoSTING 24 h prior to infection. In group 3, we treated the contact hamsters with NanoSTING 12 h after the cohousing period began. We euthanized the contact and index hamsters on day 4 of cohousing. Viral titers in the nasal tissue of the index and contact hamsters were used as primary endpoints. B, C Infectious viral particles in the nasal tissue of contact hamsters at day 2 and day 5 after viral administration post-infection were measured by endpoint titration assay. The dotted line indicates limit of detection of the assay (LOD). For (B, C), analysis was performed using a two-tailed Mann–Whitney U-test. Individual data points represent independent biological replicates taken from separate animals; vertical bars show mean values with error bars representing SEM. Each dot represents an individual hamster. Mann–Whitney test: ****p < 0.0001; ***p < 0.001; **p < 0.01; *p < 0.05; ns not significant. Data presented as combined results from one (B, C) independent animal experiment. Gender was tested as a variable with an equal number of male and female hamsters included in the study. See supplementary Fig. 13. Abbreviations- NS-Pro: Prophylactic treatment with NanoSTING; NS-Tx-Post-exposure treatment with NanoSTING. A and parts of B, C—Created with BioRender.com released under a Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International license (https://creativecommons.org/licenses/by-nc-nd/4.0/deed.en) Number of animals: n = 8/group. Source data are provided as a Source Data file.