FIGURE 6. HMGB1 reduces BK channel function and leads to a loss of ASL volume in CFBE cells in vitro.

a) Representative tracing of ATP-stimulated I_SC with a basolateral to apical K⁺ gradient and apical to basolateral Na⁺ gradient [34] from fully differentiated CFBE cells cultured in ALI media with starting glucose concentrations of 5.5 mM treated for 24 h with recombinant HMGB1 (100 ng/mL) or vehicle (water) control. b) BK activity is significantly decreased in CFBE cells treated with recombinant HMGB1 (n=5 from 4 CF lungs). c) CFBE cells treated with recombinant HMGB1 show increased ASL absorption (as indicated by a more negative ΔASL volume) over 24 h. * p < 0.05, Student’s t-test. Data are shown as mean ± S.E.M.