Published March 1, 2010 - More info
Chronic bacterial airway infections are the major cause of mortality in cystic fibrosis (CF). Normal airway defenses include reflex stimulation of submucosal gland mucus secretion by sensory neurons that release substance P (SubP). CFTR is an anion channel involved in fluid secretion and mutated in CF; the role of CFTR in secretions stimulated by SubP is unknown. We used optical methods to measure SubP-mediated secretion from human submucosal glands in lung transplant tissue. Glands from control but not CF subjects responded to mucosal chili oil. Similarly, serosal SubP stimulated secretion in more than 60% of control glands but only 4% of CF glands. Secretion triggered by SubP was synergistic with vasoactive intestinal peptide and/or forskolin but not with carbachol; synergy was absent in CF glands. Pig glands demonstrated a nearly 10-fold greater response to SubP. In 10 of 11 control glands isolated by fine dissection, SubP caused cell volume loss, lumen expansion, and mucus flow, but in 3 of 4 CF glands, it induced lumen narrowing. Thus, in CF, the reduced ability of mucosal irritants to stimulate airway gland secretion via SubP may be another factor that predisposes the airways to infections.
Jae Young Choi, Monal Khansaheb, Nam Soo Joo, Mauri E. Krouse, Robert C. Robbins, David Weill, Jeffrey J. Wine
Original citation: J. Clin. Invest.2009;119(5):1189–1200. doi:10.1172/JCI37284.
Citation for this corrigendum: J. Clin. Invest.2010;120(3):931–932. doi:10.1172/JCI37284C1.
Following the publication of this manuscript, the authors discovered carbachol contamination of an aliquot of substance P used to generate the data in Figures 7A and 7B in the published version of this work. The authors have performed the relevant experiments again with a fresh, uncontaminated aliquot of substance P. The previously published data and the corrected data are compared in Table 3 below. The corrected text describing the new data for the Results section and the corrected Figure 7 appear below. The authors confirm that the conclusions of their study remain unchanged.
Evidence that SubP stimulates gland secretion, in part, via elevating [Ca (A) Fluorescence changes in response to 10 μM SubP and 10 μM carbachol. Cell diameters in images are approximately 20 microns. (B) [Ca2+]i versus time for 10 cells from images in A, measured in response to sequential pulses of 10 μM SubP and 10 μM carbachol. (C) [Ca2+]i versus time for 10 cells from images in A, measured in response to sequential pulses of 10 μM SubP without and with 5 μM atropine (Atr). Fluorescence ratio, 340 nm/380 nm. (D) Mean response to SubP in presence or absence of BAPTA-AM (500 μM); 4 experiments from 2 HN and 1 DC subjects (16–20 glands). Error bars are SEM. (E) Mean response to SubP in the absence and presence of clotrimazole (25 μM), which blocks Ca2+-activated K+ channels (n = 4, 27–42 glands). *P < 0.05 versus SubP responses. Error bars are SEM.
Summary of original and new experiments with Substance P and intracellular calcium
In unstimulated cells, [Ca2+]i was 70–140 nM. SubP increased [Ca2+]i in 47 of 58 cells from 8 subjects by 133 ± 35 nM (peak value). All 58 cells responded to carbachol with increases in [Ca2+]i that were larger than those to SubP; the responses to 1 and 10 mM carbachol were 186 ± 17 nM and 231 ± 36 nM, respectively. We considered the possibility that gland cells that are unresponsive to SubP might be a different cell type. To help differentiate serous and mucous cells in some of the dispersed cell preparations, we used PAS staining and observed a negative correlation between PAS reactivity and SubP responsiveness. For SubP-responsive cells, 7 of 25 (28%) were PAS positive (contain mucus), while for SubP-nonresponsive cells, 6 of 8 (75%) were PAS positive.
The authors regret the errors.