Fig. 4.

Neutralizing antibody responses in the nasal mucosae of vaccinated and subjects with hybrid immunity. (a) Each dot represents the neutralizing titer (FRNT₅₀) of an individual NLF sample against SARS-CoV-2 ancestral (a) and Omicron BA.5 variant (b). (c) IgA antibodies were purified from the NLFs, each symbol represents the same subject. Neutralizing titers against ancestral SARS-CoV-2 measured from different fractions are displayed. The generalized linear model was used to determine differences of means, p values are shown above brackets.