Journal: Nature Communications
Article Title: Cationic crosslinked carbon dots-adjuvanted intranasal vaccine induces protective immunity against Omicron-included SARS-CoV-2 variants
doi: 10.1038/s41467-023-38066-8
Figure Lengend Snippet: a Immunization scheme. Mice/rabbits were immunized intranasally with PBS, RBD-HR, or CCD/RBD-HR on days 0, 14, and 28. b , c Serum anti-RBD-HR IgG titers in immunized mice ( b ) and rabbits ( c ) on day 35. d , e Neutralizing of authentic viruses ( d ) and pseudoviruses ( e ) of SARS-CoV-2 by the immune sera on day 35. f RBD-HR-specific IgA levels in BAL fluid on day 35. Immunized mice were challenged with 5 × 10 5 TCID 50 of Omicron viruses and sacrificed at 4 dpi. g Viral RNA levels in the nasal turbinates, trachea, and lungs at 4 dpi. h Histopathological changes (left) and pathological scores (right) of the lung tissues at 4 dpi. Scale bar: 100 μm. Similar results were obtained in five independent experiments. i, j Serum RBD-HR-specific IgG levels ( i ) and their function in neutralizing SARS-CoV-2 variant pseudoviruses ( j ) on day 260. On day 56, blood ( k ), bone marrow ( l ), and spleen ( m ) were harvested to assess SARS-CoV-2 RBD-specific IgG ASCs with ELISpot. Images (left) and quantification (right) of IgG spot-forming cells among lymphocytes were displayed. RBD-specific IgG-producing CD138 + plasma cells in the blood and bone marrow ( n ), memory B cells (RBD + CD38 + CD80 + ) in the blood, bone marrow, and spleen ( o ) were assayed with FCM. p , q Antigen-experienced (CD44 + ) and activated (CD69 + ) CD4 + /CD8 + T cells in the spleen were determined with FCM after re-stimulation with RBD protein peptide pools. r Splenic CD4 + and CD8 + T cells were assessed for IL-4 and IFN-γ expression with intracellular cytokine staining after restimulation with RBD protein peptide pools or irrelevant antigens. Data were displayed with floating bars in ( k – r ). The middle line indicates the median and the box shows the data range. Data were presented as mean values ± SEM. n = 4–5 mice in ( b , d – r ). n = 3 rabbits in ( c ). P values were calculated with one-way ANOVA followed by Dunnett’s multiple comparisons test in ( b , c , f – i , k – q) . Two-way ANOVA followed by Sidak’s multiple comparisons test in ( d , e , and j ). Two-way ANOVA followed by Tukey’s multiple comparisons test in ( r ). Source data are provided as a Source Data file.
Article Snippet: Following additional five washes, TMB ELISpot substrate solution (Mabtech, Sweden) was added for spot formation.
Techniques: Variant Assay, Enzyme-linked Immunospot, Clinical Proteomics, Expressing, Staining