Fig. 2

The asymmetric gas setup maintains the viability of Fn. Representative flow cytometry results for a Fn 23726 and b Fn 25586 under asymmetric gas coculture (with TIGK monolayer), normoxic coculture (with TIGK monolayer), anaerobic condition (in the anaerobic workstation), and dead cell negative control after heat treatment. The MOI was 1. SSC: side scattering. c Viability quantification of Fn strains 23726/25586 assessed by flow cytometry following different treatment groups, including the asymmetric gas coculture, normoxic coculture, anaerobic culture (positive control), and dead cell negative control after heat treatment (N.S., P > 0.05, ** P < 0.01, *** P < 0.001, n = 2 technical replicates, N = 3 biological replicates). CFUs of d Fn 23726 and e Fn 25586 in the apical chamber under normoxic and asymmetric coculture conditions at 0, 12, and 24 h time points (n = 2, N = 3). The MOI was 1